Author name code: gomory ADS astronomy entries on 2022-09-14 author:"Gomory, Peter" ------------------------------------------------------------------------ Title: The Solar Activity Monitor Network - SAMNet Authors: Erdélyi, Robertus; Korsós, Marianna B.; Huang, Xin; Yang, Yong; Pizzey, Danielle; Wrathmall, Steven A.; Hughes, Ifan G.; Dyer, Martin J.; Dhillon, Vikram S.; Belucz, Bernadett; Brajša, Roman; Chatterjee, Piyali; Cheng, Xuewu; Deng, Yuanyong; Domínguez, Santiago Vargas; Joya, Raúl; Gömöry, Peter; Gyenge, Norbert G.; Hanslmeier, Arnold; Kucera, Ales; Kuridze, David; Li, Faquan; Liu, Zhong; Xu, Long; Mathioudakis, Mihalis; Matthews, Sarah; McAteer, James R. T.; Pevtsov, Alexei A.; Pötzi, Werner; Romano, Paolo; Shen, Jinhua; Temesváry, János; Tlatov, Andrey G.; Triana, Charles; Utz, Dominik; Veronig, Astrid M.; Wang, Yuming; Yan, Yihua; Zaqarashvili, Teimuraz; Zuccarello, Francesca Bibcode: 2022JSWSC..12....2E Altcode: The Solar Activity Magnetic Monitor (SAMM) Network (SAMNet) is a future UK-led international network of ground-based solar telescope stations. SAMNet, at its full capacity, will continuously monitor the Sun's intensity, magnetic, and Doppler velocity fields at multiple heights in the solar atmosphere (from photosphere to upper chromosphere). Each SAMM sentinel will be equipped with a cluster of identical telescopes each with a different magneto-optical filter (MOFs) to take observations in K I, Na D, and Ca I spectral bands. A subset of SAMM stations will have white-light coronagraphs and emission line coronal spectropolarimeters. The objectives of SAMNet are to provide observational data for space weather research and forecast. The goal is to achieve an operationally sufficient lead time of e.g., flare warning of 2-8 h and provide many sought-after continuous synoptic maps (e.g., LoS magnetic and velocity fields, intensity) of the lower solar atmosphere with a spatial resolution limited only by seeing or diffraction limit, and with a cadence of 10 min. The individual SAMM sentinels will be connected to their master HQ hub where data received from all the slave stations will be automatically processed and flare warning issued up to 26 h in advance. Title: Prominence instability and CMEs triggered by massive coronal rain in the solar atmosphere Authors: Vashalomidze, Z.; Zaqarashvili, T. V.; Kukhianidze, V.; Ramishvili, G.; Hanslmeier, A.; Gömöry, P. Bibcode: 2022A&A...658A..18V Altcode: 2021arXiv211001287V Context. The triggering process for prominence instability and consequent coronal mass ejections (CMEs) is not fully understood. Prominences are maintained by the Lorentz force against the gravity; therefore, reduction of the prominence mass due to the coronal rain may cause the change of the force balance and hence destabilisation of the structures.
Aims: We aim to study the observational evidence of the influence of coronal rain on the stability of prominence and subsequent eruption of CMEs.
Methods: We used the simultaneous observations from the Atmospheric Imaging Assembly (AIA) of Solar Dynamics Observatory (SDO) and Sun Earth Connection Coronal and Heliospheric Investigation (SECHHI) of Solar Terrestrial Relations Observatory (STEREO) spacecrafts from different angles to follow the dynamics of prominence and to study the role of coronal rain in their destabilisation.
Results: Three different prominences observed during the years 2011-2012 were analysed using observations acquired by SDO and STEREO. In all three cases, massive coronal rain from the prominence body led to the destabilisation of prominence and subsequently to the eruption of CMEs. The upward rising of prominences consisted of the slow and fast rise phases. The coronal rain triggered the initial slow rise of prominences, which led to the final instability (the fast rise phase) after 18-28 h in all cases. The estimated mass flux carried by coronal rain blobs showed that the prominences became unstable after 40% of mass loss.
Conclusions: We suggest that the initial slow rise phase was triggered by the mass loss of prominence due to massive coronal rain, while the fast rise phase (the consequent instability of prominences) was caused by the torus instability and/or magnetic reconnection with the overlying coronal field. Therefore, the coronal rain triggered the instability of prominences and consequent CMEs. If this is the case, then the coronal rain can be used to predict the CMEs and hence to improve the space weather predictions. Title: Observational evidence for two-component distributions describing solar magnetic bright points Authors: Berrios Saavedra, Gerardine; Utz, Dominik; Vargas Domínguez, Santiago; Campos Rozo, José Iván; González Manrique, Sergio Javier; Gömöry, Peter; Kuckein, Christoph; Balthasar, Horst; Zelina, Peter Bibcode: 2022A&A...657A..79B Altcode: 2021arXiv211012404B Context. High-resolution observations of the solar photosphere reveal the presence of fine structures, in particular the so-called Magnetic Bright Points (MBPs), which are small-scale features associated with strong magnetic field regions of the order of kilogauss (kG). It is especially relevant to study these magnetic elements, which are extensively detected in all moments during the solar cycle, in order to establish their contribution to the behavior of the solar atmosphere, and ultimately a plausible role within the coronal heating problem.
Aims: Characterisation of size and velocity distributions of MBPs in the solar photosphere in two different datasets of quiet Sun images acquired with high-resolution solar instruments i.e. Solar Optical Telescope SOT/Hinode and the High-resolution Fast Imager HiFI/GREGOR, in the G-band (4308 Å).
Methods: In order to detect the MBPs, an automatic segmentation and identification algorithm is used. Next, the identified features were tracked to measure their proper motions. Finally, a statistical analysis of hundreds of MBPs is carried out, generating histograms for areas, diameters and horizontal velocities.
Results: This work establishes that areas and diameters of MBPs display log-normal distributions that are well-fitted by two different components, whereas the velocity vector components follow Gaussians and the vector magnitude a Rayleigh distribution revealing again for all vector elements a two component composition.
Conclusions: The results can be interpreted as due to the presence of two different populations of MBPs in the solar photosphere one likely related to stronger network magnetic flux elements and the other one to weaker intranetwork flux elemens. In particular this work concludes on the effect of the different spatial resolution of GREGOR and Hinode telescopes, affecting detections and average values. Title: Properties of the inner penumbra boundary and temporal evolution of a decaying sunspot (Corrigendum) Authors: Benko, M.; González Manrique, S. J.; Balthasar, H.; Gömöry, P.; Kuckein, C.; Jurčák, J. Bibcode: 2021A&A...652C...7B Altcode: No abstract at ADS Title: Evidence For Two-component Distributions Describing Magnetic Bright Points In The Solar Photosphere Authors: Vargas Domínguez, S.; Berrios Saavedra, G.; Utz, D.; Campos Rozo, J. I.; González Manrique, S.; Gömöry, Peter; Kuckein, Christoph; Balthasar, Horst; Zelina, Peter Bibcode: 2021AAS...23811310V Altcode: High-resolution observations of the Sun reveal the presence of Magnetic Bright Points (MBPs), which are small-scale features associated with strong magnetic field regions, that are found all over the solar photosphere. In this work, we characterize some physical properties and dynamics of MBPs in a quiet Sun region by using time series of images acquired with the High-resolution Fast Imager HiFI/GREGOR and Solar Optical Telescope SOT/Hinode in the G-band (4308 Angstrom). An automated segmentation algorithm is used to identify the MBPs and track their evolution. The results show observational evidence for two-component distributions of areas, diameters and velocities, that can be interpreted as corresponding to different populations of MBPs. Title: Kink instability of triangular jets in the solar atmosphere Authors: Zaqarashvili, T. V.; Lomineishvili, S.; Leitner, P.; Hanslmeier, A.; Gömöry, P.; Roth, M. Bibcode: 2021A&A...649A.179Z Altcode: 2021arXiv210209952Z Context. It is known that hydrodynamic triangular jets (i.e. the jet with maximal velocity at its axis, which linearly decreases at both sides) are unstable to anti-symmetric kink perturbations. The inclusion of the magnetic field may lead to the stabilisation of the jets. Jets and complex magnetic fields are ubiquitous in the solar atmosphere, which suggests the possibility of the kink instability in certain cases.
Aims: The aim of the paper is to study the kink instability of triangular jets sandwiched between magnetic tubes (or slabs) and its possible connection to observed properties of the jets in the solar atmosphere.
Methods: A dispersion equation governing the kink perturbations is obtained through matching of analytical solutions at the jet boundaries. The equation is solved analytically and numerically for different parameters of jets and surrounding plasma. The analytical solution is accompanied by a numerical simulation of fully non-linear magnetohydrodynamic (MHD) equations for a particular situation of solar type II spicules.
Results: Magnetohydrodynamic triangular jets are unstable to the dynamic kink instability depending on the Alfvén Mach number (the ratio of flow to Alfvén speeds) and the ratio of internal and external densities. When the jet has the same density as the surrounding plasma, only super-Alfvénic flows are unstable. However, denser jets are also unstable in a sub-Alfvénic regime. Jets with an angle to the ambient magnetic field have much lower thresholds of instability than field-aligned flows. Growth times of the kink instability are estimated to be 6−15 min for type I spicules and 5−60 s for type II spicules matching with their observed lifetimes. The numerical simulation of full non-linear equations shows that the transverse kink pulse locally destroys the jet in less than a minute in type II spicule conditions.
Conclusions: Dynamic kink instability may lead to the full breakdown of MHD flows and consequently to an observed disappearance of spicules.

Movies associated to Fig. 9 are available at https://www.aanda.org Title: Magnetically coupled atmosphere, fast sausage MHD waves, and forced magnetic field reconnection during the SOL2014-09-10T17:45 flare Authors: Mészárosová, H.; Gömöry, P. Bibcode: 2020A&A...643A.140M Altcode: 2020arXiv201001527M
Aims: We study the physical properties and behaviour of the solar atmosphere during the GOES X1.6 solar flare on 2014 September 10.
Methods: The steady plasma flows and the fast sausage MHD waves were analysed with the wavelet separation method. The magnetically coupled atmosphere and the forced magnetic field reconnection were studied with the help of the Vertical-Current Approximation Non-linear Force-Free Field code.
Results: We studied a mechanism of MHD wave transfer from the photosphere without dissipation or reflection before reaching the corona and a mechanism of the wave energy distribution over the solar corona. We report a common behaviour of (extreme)ultraviolet steady plasma flows (speed of 15.3 → 10.9 km s-1) and fast sausage MHD waves (Alfvén speed of 13.7 → 10.3 km s-1 and characteristic periods of 1587 → 1607 s), propagating in cylindrical plasma waveguides of the individual atmospheric layers (photosphere → corona) observed by SDO/AIA/HMI and IRIS space instruments. A magnetically coupled solar atmosphere by a magnetic field flux tube above a sunspot umbra and a magnetic field reconnection forced by the waves were analysed. The solar seismology with trapped, leakage, and tunnelled modes of the waves, dissipating especially in the solar corona, is discussed with respect to its possible contribution to the outer atmosphere heating.
Conclusions: We demonstrate that a dispersive nature of fast sausage MHD waves, which can easily generate the leaky and other modes propagating outside of their waveguide, and magnetic field flux tubes connecting the individual atmospheric layers can distribute the magnetic field energy across the active region. This mechanism can contribute to the coronal energy balance and to our knowledge on how the coronal heating is maintained.

Movie associated to Fig. 4 is available at https://www.aanda.org Title: The dynamics of a solar arch filament system from the chromosphere to the photosphere Authors: González Manrique, S. J.; Kuckein, C.; Pastor Yabar, A.; Diercke, A.; Collados, M.; Gömöry, P.; Zhong, S.; Hou, Y.; Denker, C. Bibcode: 2020sea..confE.199G Altcode: We study the dynamics of plasma along the legs of an arch filament system (AFS) from the chromosphere to the photosphere, observed with high-cadence spectroscopic data from two ground-based solar telescopes: the GREGOR telescope (Tenerife) using the GREGOR Infrared Spectrograph in the He I 10830 Å range and the Swedish Solar Telescope (La Palma) using the CRisp Imaging Spectro-Polarimeter to observe the Ca II 8542 Å and Fe I 6173 Å spectral lines. The temporal evolution of the draining of the plasma was followed along the legs of a single arch filament from the chromosphere to the photosphere. The average Doppler velocities inferred at the upper chromosphere from the He I 10830 Å triplet reach velocities up to 20-24 km s-1, and in the lower chromosphere and upper photosphere the Doppler velocities reach up to 11 km s-1 and 1.5 km s-1 in the case of the Ca II 8542 Å and Si I 10827 Å spectral lines, respectively. The evolution of the Doppler velocities at different layers of the solar atmosphere (chromosphere and upper photosphere) shows that they follow the same line-of-sight (LOS) velocity patern, which confirms the observational evidence that the plasma drains toward the photosphere as proposed in models of AFSs. The observations and the nonlinear force-free field (NLFFF) extrapolations demonstrate that the magnetic field loops of the AFS rise with time. Title: Magnetic Flux Emergence in a Coronal Hole Authors: Palacios, Judith; Utz, Dominik; Hofmeister, Stefan; Krikova, Kilian; Gömöry, Peter; Kuckein, Christoph; Denker, Carsten; Verma, Meetu; González Manrique, Sergio Javier; Campos Rozo, Jose Iván; Koza, Július; Temmer, Manuela; Veronig, Astrid; Diercke, Andrea; Kontogiannis, Ioannis; Cid, Consuelo Bibcode: 2020SoPh..295...64P Altcode: 2020arXiv200611779P A joint campaign of various space-borne and ground-based observatories, comprising the Japanese Hinode mission (Hinode Observing Plan 338, 20 - 30 September 2017), the GREGOR solar telescope, and the Vacuum Tower Telescope (VTT), investigated numerous targets such as pores, sunspots, and coronal holes. In this study, we focus on the coronal hole region target. On 24 September 2017, a very extended non-polar coronal hole developed patches of flux emergence, which contributed to the decrease of the overall area of the coronal hole. These flux emergence patches erode the coronal hole and transform the area into a more quiet-Sun-like area, whereby bipolar magnetic structures play an important role. Conversely, flux cancellation leads to the reduction of opposite-polarity magnetic fields and to an increase in the area of the coronal hole. Title: Tracking Downflows from the Chromosphere to the Photosphere in a Solar Arch Filament System Authors: González Manrique, Sergio Javier; Kuckein, Christoph; Pastor Yabar, Adur; Diercke, Andrea; Collados, Manuel; Gömöry, Peter; Zhong, Sihui; Hou, Yijun; Denker, Carsten Bibcode: 2020ApJ...890...82G Altcode: 2020arXiv200107078G We study the dynamics of plasma along the legs of an arch filament system (AFS) from the chromosphere to the photosphere, observed with high-cadence spectroscopic data from two ground-based solar telescopes: the GREGOR telescope (Tenerife) using the GREGOR Infrared Spectrograph in the He I 10830 Å range and the Swedish Solar Telescope (La Palma) using the CRisp Imaging Spectro-Polarimeter to observe the Ca II 8542 Å and Fe I 6173 Å spectral lines. The temporal evolution of the draining of the plasma was followed along the legs of a single arch filament from the chromosphere to the photosphere. The average Doppler velocities inferred at the upper chromosphere from the He I 10830 Å triplet reach velocities up to 20-24 km s-1, and in the lower chromosphere and upper photosphere the Doppler velocities reach up to 11 km s-1 and 1.5 km s-1 in the case of the Ca II 8542 Å and Si I 10827 Å spectral lines, respectively. The evolution of the Doppler velocities at different layers of the solar atmosphere (chromosphere and upper photosphere) shows that they follow the same line-of-sight (LOS) velocity pattern, which confirms the observational evidence that the plasma drains toward the photosphere as proposed in models of AFSs. The Doppler velocity maps inferred from the lower photospheric Ca I 10839 Å or Fe I 6173 Å spectral lines do not show the same LOS velocity pattern. Thus, there is no evidence that the plasma reaches the lower photosphere. The observations and the nonlinear force-free field (NLFFF) extrapolations demonstrate that the magnetic field loops of the AFS rise with time. We found flow asymmetries at different footpoints of the AFS. The NLFFF values of the magnetic field strength help us to explain these flow asymmetries. Title: Coordinated observations between China and Europe to follow active region 12709 Authors: González Manrique, S. J.; Kuckein, C.; Gömöry, P.; Yuan, S.; Xu, Z.; Rybák, J.; Balthasar, H.; Schwartz, P. Bibcode: 2020IAUS..354...58G Altcode: 2020IAUS..354...58M; 2019arXiv191208611G We present the first images of a coordinated campaign to follow active region NOAA 12709 on 2018 May 13 as part of a joint effort between three observatories (China-Europe). The active region was close to disk center and enclosed a small pore, a tight polarity inversion line and a filament in the chromosphere. The active region was observed with the 1.5-meter GREGOR solar telescope on Tenerife (Spain) with spectropolarimetry using GRIS in the He i 10830 Å spectral range and with HiFI using two broad-band filter channels. In addition, the Lomnicky Stit Observatory (LSO, Slovakia) recorded the same active region with the new Solar Chromospheric Detector (SCD) in spectroscopic mode at Hα 6562 Å. The third ground-based telescope was located at the Fuxian Solar Observatory (China), where the active region was observed with the 1-meter New Vacuum Solar Telescope (NVST), using the Multi-Channel High Resolution Imaging System at Hα 6562 Å. Overlapping images of the active region from all three telescopes will be shown as well as preliminary Doppler line-of-sight (LOS) velocities. The potential of such observations are discussed. Title: Revisiting the building blocks of solar magnetic fields by GREGOR Authors: Utz, Dominik; Kuckein, Christoph; Campos Rozo, Jose Iván; González Manrique, Sergio Javier; Balthasar, Horst; Gömöry, Peter; Hernández, Judith Palacios; Denker, Carsten; Verma, Meetu; Kontogiannis, Ioannis; Krikova, Kilian; Hofmeister, Stefan; Diercke, Andrea Bibcode: 2020IAUS..354...38U Altcode: The Sun is our dynamic host star due to its magnetic fields causing plentiful of activity in its atmosphere. From high energetic flares and coronal mass ejections (CMEs) to lower energetic phenomena such as jets and fibrils. Thus, it is of crucial importance to learn about formation and evolution of solar magnetic fields. These fields cover a wide range of spatial and temporal scales, starting on the larger end with active regions harbouring complex sunspots, via isolated pores, down to the smallest yet resolved elements - so-called magnetic bright points (MBPs). Here, we revisit the various manifestations of solar magnetic fields by the largest European solar telescope in operation, the 1.5-meter GREGOR telescope. We show images from the High-resolution Fast Imager (HiFI) and spectropolarimetric data from the GREGOR Infrared Spectrograph (GRIS). Besides, we outline resolved convective features inside the larger structures - so-called light-bridges occurring on large to mid-sized scales. Title: Science Requirement Document (SRD) for the European Solar Telescope (EST) (2nd edition, December 2019) Authors: Schlichenmaier, R.; Bellot Rubio, L. R.; Collados, M.; Erdelyi, R.; Feller, A.; Fletcher, L.; Jurcak, J.; Khomenko, E.; Leenaarts, J.; Matthews, S.; Belluzzi, L.; Carlsson, M.; Dalmasse, K.; Danilovic, S.; Gömöry, P.; Kuckein, C.; Manso Sainz, R.; Martinez Gonzalez, M.; Mathioudakis, M.; Ortiz, A.; Riethmüller, T. L.; Rouppe van der Voort, L.; Simoes, P. J. A.; Trujillo Bueno, J.; Utz, D.; Zuccarello, F. Bibcode: 2019arXiv191208650S Altcode: The European Solar Telescope (EST) is a research infrastructure for solar physics. It is planned to be an on-axis solar telescope with an aperture of 4 m and equipped with an innovative suite of spectro-polarimetric and imaging post-focus instrumentation. The EST project was initiated and is driven by EAST, the European Association for Solar Telescopes. EAST was founded in 2006 as an association of 14 European countries. Today, as of December 2019, EAST consists of 26 European research institutes from 18 European countries. The Preliminary Design Phase of EST was accomplished between 2008 and 2011. During this phase, in 2010, the first version of the EST Science Requirement Document (SRD) was published. After EST became a project on the ESFRI roadmap 2016, the preparatory phase started. The goal of the preparatory phase is to accomplish a final design for the telescope and the legal governance structure of EST. A major milestone on this path is to revisit and update the Science Requirement Document (SRD). The EST Science Advisory Group (SAG) has been constituted by EAST and the Board of the PRE-EST EU project in November 2017 and has been charged with the task of providing with a final statement on the science requirements for EST. Based on the conceptual design, the SRD update takes into account recent technical and scientific developments, to ensure that EST provides significant advancement beyond the current state-of-the-art. The present update of the EST SRD has been developed and discussed during a series of EST SAG meetings. The SRD develops the top-level science objectives of EST into individual science cases. Identifying critical science requirements is one of its main goals. Those requirements will define the capabilities of EST and the post-focus instrument suite. The technical requirements for the final design of EST will be derived from the SRD. Title: Observations of a Footpoint Drift of an Erupting Flux Rope Authors: Zemanová, Alena; Dudík, Jaroslav; Aulanier, Guillaume; Thalmann, Julia K.; Gömöry, Peter Bibcode: 2019ApJ...883...96Z Altcode: 2019arXiv190802082Z We analyze the imaging observations of an M-class eruptive flare of 2015 November 4. The pre-eruptive Hα filament was modeled by the nonlinear force-free field model, which showed that it consisted of two helical systems. Tether-cutting reconnection involving these two systems led to the formation of a hot sigmoidal loop structure rooted in a small hook that formed at the end of the flare ribbon. Subsequently, the hot loops started to slip away from the small hook until it disappeared. The loops continued slipping and the ribbon elongated itself by several tens of arcseconds. A new and larger hook then appeared at the end of the elongated ribbon with hot and twisted loops rooted there. After the eruption of these hot loops, the ribbon hook expanded and later contracted. We interpret these observations in the framework of the recent three-dimensional (3D) extensions to the standard solar flare model predicting the drift of the flux rope footpoints. The hot sigmoidal loop is interpreted as the flux rope, whose footpoints drift during the eruption. While the deformation and drift of the new hook can be described by the model, the displacement of the flux rope footpoint from the filament to that of the erupting flux rope indicate that the hook evolution can be more complex than those captured by the model. Title: Spectroscopy and Differential Emission Measure Diagnostics of a Coronal Dimming Associated with a Fast Halo CME Authors: Veronig, Astrid M.; Gömöry, Peter; Dissauer, Karin; Temmer, Manuela; Vanninathan, Kamalam Bibcode: 2019ApJ...879...85V Altcode: 2019arXiv190601517V We study the coronal dimming caused by the fast halo CME (deprojected speed v = 1250 km s-1) associated with the C3.7 two-ribbon flare on 2012 September 27, using Hinode/EIS spectroscopy and Solar Dynamics Observatory (SDO)/AIA Differential Emission Measure (DEM) analysis. The event reveals bipolar core dimmings encompassed by hook-shaped flare ribbons located at the ends of the flare-related polarity inversion line, and marking the footpoints of the erupting filament. In coronal emission lines of log T [K] = 5.8-6.3, distinct double-component spectra indicative of the superposition of a stationary and a fast upflowing plasma component with velocities up to 130 km s-1 are observed at these regions, which were mapped by the scanning EIS slit close in time to their impulsive dimming onset. The outflowing plasma component is found to be of the same order as and even dominant over the stationary one, with electron densities in the upflowing component of 2 × 109 cm-3 at log T [K] = 6.2. The density evolution in core-dimming regions derived from SDO/AIA DEM analysis reveals impulsive reductions by 40%-50% within ≲10 minutes and remains at these reduced levels for hours. The mass-loss rate derived from the EIS spectroscopy in the dimming regions is of the same order as the mass increase rate observed in the associated white-light CME (1 × 1012 g s-1), indicating that the CME mass increase in the coronagraphic field of view results from plasma flows from below and not from material piled up ahead of the outward-moving and expanding CME front. Title: Spectropolarimetric Observations of an Arch Filament System with GREGOR Authors: Balthasar, H.; Gömöry, P.; González Manrique, S. J.; Kuckein, C.; Kučera, A.; Schwartz, P.; Berkefeld, T.; Collados, M.; Denker, C.; Feller, A.; Hofmann, A.; Schlichenmaier, R.; Schmidt, D.; Schmidt, W.; Sigwarth, M.; Sobotka, M.; Solanki, S. K.; Soltau, D.; Staude, J.; Strassmeier, K. G.; von der Lühe, O. Bibcode: 2019ASPC..526..217B Altcode: 2018arXiv180401789B We observed an arch filament system (AFS) in a sunspot group with the GREGOR Infrared Spectrograph attached to the GREGOR solar telescope. The AFS was located between the leading sunspot of negative polarity and several pores of positive polarity forming the following part of the sunspot group. We recorded five spectro-polarimetric scans of this region. The spectral range included the spectral lines Si I 1082.7 nm, He I 1083.0 nm, and Ca I 1083.9 nm. In this work we concentrate on the silicon line which is formed in the upper photosphere. The line profiles are inverted with the code 'Stokes Inversion based on Response functions' to obtain the magnetic field vector. The line-of-sight velocities are determined independently with a Fourier phase method. Maximum velocities are found close to the ends of AFS fibrils. These maximum values amount to 2.4 km s-1 next to the pores and to 4 km s-1 at the sunspot side. Between the following pores, we encounter an area of negative polarity that is decreasing during the five scans. We interpret this by new emerging positive flux in this area canceling out the negative flux. In summary, our findings confirm the scenario that rising magnetic flux tubes cause the AFS. Title: Pre-eruption Processes: Heating, Particle Acceleration, and the Formation of a Hot Channel before the 2012 October 20 M9.0 Limb Flare Authors: Hernandez-Perez, Aaron; Su, Yang; Veronig, Astrid M.; Thalmann, Julia; Gömöry, Peter; Joshi, Bhuwan Bibcode: 2019ApJ...874..122H Altcode: 2019arXiv190208436H We report a detailed study of the pre-eruption activities that led to the occurrence of an M9.0 flare/CME event on 2012 October 20 in NOAA AR 11598. This includes the study of the preceding confined C2.4 flare that occurred on the same AR ∼25 minutes earlier. We observed that the M9.0 flare occurred as a consequence of two distinct triggering events well separated in time. The first triggering episode occurred as early as ∼20 minutes before the onset of the M9.0 flare, evidenced by the destabilization and rise of a pre-existing filament to a new position of equilibrium at a higher coronal altitude during the decay phase of the C2.4 flare. This brought the system to a magnetic configuration where the establishment of the second triggering event was favorable. The second triggering episode occurred ∼17 minutes later, during the early phase of the M9.0 flare, evidenced by the further rise of the filament and successful ejection. The second trigger is followed by a flare precursor phase, characterized by nonthermal emission and the sequential formation of a hot channel as shown by the SDO/AIA DEM (differential emission measure) maps, the RHESSI X-ray images and spectra. These observations are suggestive of magnetic reconnection and particle acceleration that can explain the precursor phase and can be directly related to the formation of the hot channel. We discuss the triggering mechanisms, their implications during the early and precursor phases and highlight the importance of early activities and preceding small confined flares to understand the initiation of large eruptive flares. Title: Properties of the inner penumbral boundary and temporal evolution of a decaying sunspot Authors: Benko, M.; González Manrique, S. J.; Balthasar, H.; Gömöry, P.; Kuckein, C.; Jurčák, J. Bibcode: 2018A&A...620A.191B Altcode: 2018arXiv181013185B Context. It has been empirically determined that the umbra-penumbra boundaries of stable sunspots are characterized by a constant value of the vertical magnetic field.
Aims: We analyzed the evolution of the photospheric magnetic field properties of a decaying sunspot belonging to NOAA 11277 between August 28-September 3, 2011. The observations were acquired with the spectropolarimeter on-board of the Hinode satellite. We aim to prove the validity of the constant vertical magnetic-field boundary between the umbra and penumbra in decaying sunspots.
Methods: A spectral-line inversion technique was used to infer the magnetic field vector from the full-Stokes profiles. In total, eight maps were inverted and the variation of the magnetic properties in time were quantified using linear or quadratic fits.
Results: We find a linear decay of the umbral vertical magnetic field, magnetic flux, and area. The penumbra showed a linear increase of the vertical magnetic field and a sharp decay of the magnetic flux. In addition, the penumbral area quadratically decayed. The vertical component of the magnetic field is weaker on the umbra-penumbra boundary of the studied decaying sunspot compared to stable sunspots. Its value seem to be steadily decreasing during the decay phase. Moreover, at any time of the sunspot decay shown, the inner penumbra boundary does not match with a constant value of the vertical magnetic field, contrary to what is seen in stable sunspots.
Conclusions: During the decaying phase of the studied sunspot, the umbra does not have a sufficiently strong vertical component of the magnetic field and is thus unstable and prone to be disintegrated by convection or magnetic diffusion. No constant value of the vertical magnetic field is found for the inner penumbral boundary. Title: Temporal evolution of arch filaments as seen in He I 10 830 Å Authors: González Manrique, S. J.; Kuckein, C.; Collados, M.; Denker, C.; Solanki, S. K.; Gömöry, P.; Verma, M.; Balthasar, H.; Lagg, A.; Diercke, A. Bibcode: 2018A&A...617A..55G Altcode: 2018arXiv180700728G
Aims: We study the evolution of an arch filament system (AFS) and of its individual arch filaments to learn about the processes occurring in them.
Methods: We observed the AFS at the GREGOR solar telescope on Tenerife at high cadence with the very fast spectroscopic mode of the GREGOR Infrared Spectrograph (GRIS) in the He I 10 830 Å spectral range. The He I triplet profiles were fitted with analytic functions to infer line-of-sight (LOS) velocities to follow plasma motions within the AFS.
Results: We tracked the temporal evolution of an individual arch filament over its entire lifetime, as seen in the He I 10 830 Å triplet. The arch filament expanded in height and extended in length from 13″ to 21″. The lifetime of this arch filament is about 30 min. About 11 min after the arch filament is seen in He I, the loop top starts to rise with an average Doppler velocity of 6 km s-1. Only two minutes later, plasma drains down with supersonic velocities towards the footpoints reaching a peak velocity of up to 40 km s-1 in the chromosphere. The temporal evolution of He I 10 830 Å profiles near the leading pore showed almost ubiquitous dual red components of the He I triplet, indicating strong downflows, along with material nearly at rest within the same resolution element during the whole observing time.
Conclusions: We followed the arch filament as it carried plasma during its rise from the photosphere to the corona. The material then drained toward the photosphere, reaching supersonic velocities, along the legs of the arch filament. Our observational results support theoretical AFS models and aids in improving future models.

The movie associated to Fig. 3 is available at https://www.aanda.org/ Title: Dynamcis and magnetic properties in coronal holes using high-resolution multi-instrument solar observations Authors: Krikova, K.; Utz, D.; Veronig, A.; Gömöry, P.; Hofmeister, S.; Temmer, M. Bibcode: 2018simi.conf...31K Altcode: Using high-resolution solar observations from the Hinode Instruments SOT/SP, EIS and XRT as well as IRIS from a coronal hole on the 26th of September 2017, we are investigating the dynamics within the coronal hole visible on the specified date. Further satellite data support is given by full disc images from SDO with the AIA and HMI instruments. EIS and IRIS data provide us with crucial information about the plasma and energy flow from the Sun's chromosphere into the corona using the EUV and UV spectra and images. Investigating the magnetic configuration as well as the dynamics and changes within the coronal hole by using the SOT/SP data will give us additional crucial insights about the physical processes leading to the corresponding changes in the higher atmosphere. We compare the Hinode data with AIA and HMI data to get a firm comprehensive picture about the connection from high resolved photospheric fields and its dynamics within the higher layer. Within the timeframe of the analysed EIS dataset two microflare events associated with a solar jet were captured, originating inside the coronal hole under investigation. We believe that it is totally worthwhile to study these features in full detail as not so much attention was paid to high energy processes within coronal holes and their basic relationship to the harboring coronal hole and they show surprisingly high downflows in the Fe XII iron line (up to 140 km/s). In the current proceeding we will outline the state of the art of this investigation and give an overview of the further steps necessary. The mentioned data were obtained during a recent GREGOR campaign with the joint support of IRIS and Hinode (HOP 338). Title: Small-scale dynamcis in a coronal-hole related to microflaring events Authors: Krikova, K.; Utz, D.; Veronig, A.; Hofmeister, S.; Temmer, M.; Gömöry, P.; Holzknecht, L. Bibcode: 2018CEAB...42....8K Altcode: Using high-resolution solar imagery and spectroscopy from the Hinode EIS and SDO instruments, we investigate the dynamics within a coronal hole observed on the 26th September 2017. Further data is given by full disc images from SDO with the AIA and HMI instruments. EIS spectra provide us with crucial information about the plasma and energy flows from the Sun's chromosphere into the corona. Within the timeframe of the analysed EIS dataset two microflares associated with a jet-like event were captured, originating inside the coronal hole under investigation. These two microflare events were analysed in the study at hand in detail. Such recurring solar transient events could contribute to the mass and energy input into the solar corona and also to the solar wind. Our analysis shows that microflare temperatures can reach up to 3 MK with a hot component close to the reconnection site. Moreover an enhanced density at the microflare region was found. The obtained EIS ion line ratios suggest a density of up to 2.9 \cdot 10^{10} cm^{-3}. Title: Generation Mechanisms of Quasi-parallel and Quasi-circular Flare Ribbons in a Confined Flare Authors: Hernandez-Perez, Aaron; Thalmann, Julia K.; Veronig, Astrid M.; Su, Yang; Gömöry, Peter; Dickson, Ewan C. Bibcode: 2017ApJ...847..124H Altcode: 2017arXiv170808612H We analyze a confined multiple-ribbon M2.1 flare (SOL2015-01-29T11:42) that originated from a fan-spine coronal magnetic field configuration, within active region NOAA 12268. The observed ribbons form in two steps. First, two primary ribbons form at the main flare site, followed by the formation of secondary ribbons at remote locations. We observe a number of plasma flows at extreme-ultraviolet temperatures during the early phase of the flare (as early as 15 minutes before the onset) propagating toward the formation site of the secondary ribbons. The secondary ribbon formation is co-temporal with the arrival of the pre-flare generated plasma flows. The primary ribbons are co-spatial with Ramaty High Energy Spectroscopic Imager (RHESSI) hard X-ray sources, whereas no enhanced X-ray emission is detected at the secondary ribbon sites. The (E)UV emission, associated with the secondary ribbons, peaks ∼1 minute after the last RHESSI hard X-ray enhancement. A nonlinear force-free model of the coronal magnetic field reveals that the secondary flare ribbons are not directly connected to the primary ribbons, but to regions nearby. Detailed analysis suggests that the secondary brightenings are produced due to dissipation of kinetic energy of the plasma flows (heating due to compression), and not due to non-thermal particles accelerated by magnetic reconnection, as is the case for the primary ribbons. Title: Flows along arch filaments observed in the GRIS `very fast spectroscopic mode' Authors: González Manrique, S. J.; Denker, C.; Kuckein, C.; Pastor Yabar, A.; Collados, M.; Verma, M.; Balthasar, H.; Diercke, A.; Fischer, C. E.; Gömöry, P.; Bello González, N.; Schlichenmaier, R.; Cubas Armas, M.; Berkefeld, T.; Feller, A.; Hoch, S.; Hofmann, A.; Lagg, A.; Nicklas, H.; Orozco Suárez, D.; Schmidt, D.; Schmidt, W.; Sigwarth, M.; Sobotka, M.; Solanki, S. K.; Soltau, D.; Staude, J.; Strassmeier, K. G.; Volkmer, R.; von der Lühe, O.; Waldmann, T. Bibcode: 2017IAUS..327...28G Altcode: 2017arXiv170102206G A new generation of solar instruments provides improved spectral, spatial, and temporal resolution, thus facilitating a better understanding of dynamic processes on the Sun. High-resolution observations often reveal multiple-component spectral line profiles, e.g., in the near-infrared He i 10830 Å triplet, which provides information about the chromospheric velocity and magnetic fine structure. We observed an emerging flux region, including two small pores and an arch filament system, on 2015 April 17 with the `very fast spectroscopic mode' of the GREGOR Infrared Spectrograph (GRIS) situated at the 1.5-meter GREGOR solar telescope at Observatorio del Teide, Tenerife, Spain. We discuss this method of obtaining fast (one per minute) spectral scans of the solar surface and its potential to follow dynamic processes on the Sun. We demonstrate the performance of the `very fast spectroscopic mode' by tracking chromospheric high-velocity features in the arch filament system. Title: Spectral Characteristics of the He I D3 Line in a Quiescent Prominence Observed by THEMIS Authors: Koza, Július; Rybák, Ján; Gömöry, Peter; Kozák, Matúš; López Ariste, Arturo Bibcode: 2017SoPh..292...98K Altcode: 2017arXiv171209255K We analyze the observations of a quiescent prominence acquired by the Téléscope Heliographique pour l'Étude du Magnetisme et des Instabilités Solaires (THEMIS) in the He I 5876 Å (He I D3) multiplet aiming to measure the spectral characteristics of the He I D3 profiles and to find for them an adequate fitting model. The component characteristics of the He I D3 Stokes I profiles are measured by the fitting system by approximating them with a double Gaussian. This model yields an He I D3 component peak intensity ratio of 5.5 ±0.4 , which differs from the value of 8 expected in the optically thin limit. Most of the measured Doppler velocities lie in the interval ± 5 km s−1, with a standard deviation of ± 1.7 km s−1 around the peak value of 0.4 km s−1. The wide distribution of the full-width at half maximum has two maxima at 0.25 Å and 0.30 Å for the He I D3 blue component and two maxima at 0.22 Å and 0.31 Å for the red component. The width ratio of the components is 1.04 ±0.18 . We show that the double-Gaussian model systematically underestimates the blue wing intensities. To solve this problem, we invoke a two-temperature multi-Gaussian model, consisting of two double-Gaussians, which provides a better representation of He I D3 that is free of the wing intensity deficit. This model suggests temperatures of 11.5 kK and 91 kK, respectively, for the cool and the hot component of the target prominence. The cool and hot components of a typical He I D3 profile have component peak intensity ratios of 6.6 and 8, implying a prominence geometrical width of 17 Mm and an optical thickness of 0.3 for the cool component, while the optical thickness of the hot component is negligible. These prominence parameters seem to be realistic, suggesting the physical adequacy of the multi-Gaussian model with important implications for interpreting He I D3 spectropolarimetry by current inversion codes. Title: Flare-induced changes of the photospheric magnetic field in a δ-spot deduced from ground-based observations Authors: Gömöry, P.; Balthasar, H.; Kuckein, C.; Koza, J.; Veronig, A. M.; González Manrique, S. J.; Kučera, A.; Schwartz, P.; Hanslmeier, A. Bibcode: 2017A&A...602A..60G Altcode: 2017arXiv170406089G
Aims: Changes of the magnetic field and the line-of-sight velocities in the photosphere are being reported for an M-class flare that originated at a δ-spot belonging to active region NOAA 11865.
Methods: High-resolution ground-based near-infrared spectropolarimetric observations were acquired simultaneously in two photospheric spectral lines, Fe I 10783 Å and Si I 10786 Å, with the Tenerife Infrared Polarimeter at the Vacuum Tower Telescope (VTT) in Tenerife on 2013 October 15. The observations covered several stages of the M-class flare. Inversions of the full-Stokes vector of both lines were carried out and the results were put into context using (extreme)-ultraviolet filtergrams from the Solar Dynamics Observatory (SDO).
Results: The active region showed high flaring activity during the whole observing period. After the M-class flare, the longitudinal magnetic field did not show significant changes along the polarity inversion line (PIL). However, an enhancement of the transverse magnetic field of approximately 550 G was found that bridges the PIL and connects umbrae of opposite polarities in the δ-spot. At the same time, a newly formed system of loops appeared co-spatially in the corona as seen in 171 Å filtergrams of the Atmospheric Imaging Assembly (AIA) on board SDO. However, we cannot exclude that the magnetic connection between the umbrae already existed in the upper atmosphere before the M-class flare and became visible only later when it was filled with hot plasma. The photospheric Doppler velocities show a persistent upflow pattern along the PIL without significant changes due to the flare.
Conclusions: The increase of the transverse component of the magnetic field after the flare together with the newly formed loop system in the corona support recent predictions of flare models and flare observations.

The movie associated to Figs. 4 and 5 is available at http://www.aanda.org Title: Understanding CMEs using plasma diagnostics of the related dimmings Authors: Vanninathan, Kamalam; Veronig, Astrid; Gomory, Peter; Dissauer, Karin; Temmer, Manuela; Hannah, Iain; Kontar, Eduard Bibcode: 2017EGUGA..19.1571V Altcode: Coronal Mass Ejections (CMEs) are often associated with dimmings that are well observed in Extreme Ultra-violet (EUV) wavelengths. Such dimmings are suggested to represent the evacuation of mass that is carried out by CMEs and are a unique and indirect means to study CME properties. While Earth-directed CMEs (on-disk CMEs) are difficult to observe due to the bright background solar disk and projection effects, their corresponding dimmings are clearly discernible and ideally suited for analysis. Using data from the 6 EUV channels of Solar Dynamics Observatory/Atmospheric Imaging Assembly for Differential Emission Measure (DEM) diagnostics, we determine the plasma characteristics of the dimming region. These data are well suited for this kind of study due to the good temperature ranges covered by the multiple passbands of the instrument. We analyse 7 on-disk and 5 off-limb events and derive the weighted density and temperature as a function of time, from the DEMs. From such an analysis we differentiate 2 types of dimming regions: core and secondary dimmings. Core dimmings often occur in pairs lying on either sides of the active region and in opposite polarity regions while the secondary dimming is more extended. In both the regions the derived plasma parameters reach a minimum within 30-60 min after the flare. For each event the core dimming region shows a higher decrease in density and temperature than the corresponding secondary dimming regions. The values of these parameters remains low within the core dimming region for the entire duration of this study ( 10 hrs after the flare) while the secondary dimming region starts to show a gradual increase after 1-2 hrs. We also use spectroscopic data from Hinode/Extreme-Ultraviolet Imaging Spectrometer to differentiate core and secondary dimming regions. We find that the Fe XIII 202 Å line shows double component profiles within the core dimming region with strong blueshifts of 100 km/s while the secondary dimming region has weak upflows of 10 km/s. We conclude that the core dimming region corresponds to footpoints of the erupting flux rope from where there is continuous strong upflowing plasma for at least 10 hrs after the flare, while the secondary dimming region begins to refill within 1-2 hrs. These measurements can be used to deduce information about the mass of on-disk CMEs where white light measurements can fail. We also confirm that the dimmings are mainly caused by density decrease and not temperature changes. DEM analysis is a strong tool to decipher CME properties from dimming regions. Title: Flare induced changes of the photospheric magnetic field in a delta-spot deduced from ground-based observations Authors: Gömöry, P.; Balthasar, H.; Kuckein, C.; Koza, J.; Kuĉera, A.; González Manrique, S. J.; Schwartz, P.; Veronig, A. M.; Hanslmeier, A. Bibcode: 2017psio.confE.107G Altcode: No abstract at ADS Title: NLTE modeling of a small active region filament observed with the VTT Authors: Schwartz, P.; Balthasar, H.; Kuckein, C.; Koza, J.; Gömöry, P.; Rybák, J.; Heinzel, P.; Kučera, A. Bibcode: 2016AN....337.1045S Altcode: An active region mini-discretionary-filament was observed with the Vacuum Tower Telescope (VTT) in Tenerife simultaneously in the He I infrared triplet using the Tenerife Infrared Polarimeter 1 (TIP 1), in Hα with the TESOS Fabry-Pérot interferometer, and in Ca II 8542 Å with the VTT spectrograph. The spectropolarimetric data were inverted using the HAZEL code and Hα profiles were modelled by solving a NLTE radiative transfer in a simple isobaric and isothermal 2D slab irradiated both from its bottom and sides from the solar surface. It was found that the mini-discretionary-filament is composed of horizontal fluxtubes, along which the cool plasma of T∼10 000 K can flow with very large, even supersonic, velocities. Title: Spectropolarimetric observations of an arch filament system with the GREGOR solar telescope Authors: Balthasar, H.; Gömöry, P.; González Manrique, S. J.; Kuckein, C.; Kavka, J.; Kučera, A.; Schwartz, P.; Vašková, R.; Berkefeld, T.; Collados Vera, M.; Denker, C.; Feller, A.; Hofmann, A.; Lagg, A.; Nicklas, H.; Orozco Suárez, D.; Pastor Yabar, A.; Rezaei, R.; Schlichenmaier, R.; Schmidt, D.; Schmidt, W.; Sigwarth, M.; Sobotka, M.; Solanki, S. K.; Soltau, D.; Staude, J.; Strassmeier, K. G.; Volkmer, R.; von der Lühe, O.; Waldmann, T. Bibcode: 2016AN....337.1050B Altcode: 2016arXiv160901514B Arch filament systems occur in active sunspot groups, where a fibril structure connects areas of opposite magnetic polarity, in contrast to active region filaments that follow the polarity inversion line. We used the GREGOR Infrared Spectrograph (GRIS) to obtain the full Stokes vector in the spectral lines Si I λ1082.7 nm, He I λ1083.0 nm, and Ca I λ1083.9 nm. We focus on the near-infrared calcium line to investigate the photospheric magnetic field and velocities, and use the line core intensities and velocities of the helium line to study the chromospheric plasma. The individual fibrils of the arch filament system connect the sunspot with patches of magnetic polarity opposite to that of the spot. These patches do not necessarily coincide with pores, where the magnetic field is strongest. Instead, areas are preferred not far from the polarity inversion line. These areas exhibit photospheric downflows of moderate velocity, but significantly higher downflows of up to 30 km s-1 in the chromospheric helium line. Our findings can be explained with new emerging flux where the matter flows downward along the field lines of rising flux tubes, in agreement with earlier results. Title: Fitting peculiar spectral profiles in He I 10830Å absorption features Authors: González Manrique, S. J.; Kuckein, C.; Pastor Yabar, A.; Collados, M.; Denker, C.; Fischer, C. E.; Gömöry, P.; Diercke, A.; Bello González, N.; Schlichenmaier, R.; Balthasar, H.; Berkefeld, T.; Feller, A.; Hoch, S.; Hofmann, A.; Kneer, F.; Lagg, A.; Nicklas, H.; Orozco Suárez, D.; Schmidt, D.; Schmidt, W.; Sigwarth, M.; Sobotka, M.; Solanki, S. K.; Soltau, D.; Staude, J.; Strassmeier, K. G.; Verma, M.; Volkmer, R.; von der Lühe, O.; Waldmann, T. Bibcode: 2016AN....337.1057G Altcode: 2016arXiv160300679G The new generation of solar instruments provides better spectral, spatial, and temporal resolution for a better understanding of the physical processes that take place on the Sun. Multiple-component profiles are more commonly observed with these instruments. Particularly, the He I 10830 Å triplet presents such peculiar spectral profiles, which give information on the velocity and magnetic fine structure of the upper chromosphere. The purpose of this investigation is to describe a technique to efficiently fit the two blended components of the He I 10830 Å triplet, which are commonly observed when two atmospheric components are located within the same resolution element. The observations used in this study were taken on 2015 April 17 with the very fast spectroscopic mode of the GREGOR Infrared Spectrograph (GRIS) attached to the 1.5-m GREGOR solar telescope, located at the Observatorio del Teide, Tenerife, Spain. We apply a double-Lorentzian fitting technique using Levenberg-Marquardt least-squares minimization. This technique is very simple and much faster than inversion codes. Line-of-sight Doppler velocities can be inferred for a whole map of pixels within just a few minutes. Our results show sub- and supersonic downflow velocities of up to 32 km s-1 for the fast component in the vicinity of footpoints of filamentary structures. The slow component presents velocities close to rest. Title: Broadband microwave sub-second pulsations in an expanding coronal loop of the 2011 August 10 flare Authors: Mészárosová, H.; Rybák, J.; Kashapova, L.; Gömöry, P.; Tokhchukova, S.; Myshyakov, I. Bibcode: 2016A&A...593A..80M Altcode: 2016arXiv160904217M
Aims: We studied the characteristic physical properties and behavior of broadband microwave sub-second pulsations observed in an expanding coronal loop during the GOES C2.4 solar flare on 2011 August 10.
Methods: The complex microwave dynamic spectrum and the expanding loop images were analyzed with the help of SDO/AIA/HMI, RHESSI, and the STEREO/SECCHI-EUVI data processing software, wavelet analysis methods, the GX Simulator tool, and the NAFE method.
Results: We found sub-second pulsations and other different burst groups in the complex radio spectrum. The broadband (bandwidth about 1 GHz) sub-second pulsations (temporal period range 0.07-1.49 s, no characteristic dominant period) lasted 70 s in the frequency range 4-7 GHz. These pulsations were not correlated at their individual frequencies, had no measurable frequency drift, and zero polarization. In these pulsations, we found the signatures of fast sausage magnetoacoustic waves with the characteristic periods of 0.7 and 2 s. The other radio bursts showed their characteristic frequency drifts in the range of -262-520 MHz s-1. They helped us to derive average values of 20-80 G for the coronal magnetic field strength in the place of radio emission. It was revealed that the microwave event belongs to an expanding coronal loop with twisted sub-structures observed in the 131, 94, and 193 Å SDO/AIA channels. Their slit-time diagrams were compared with the location of the radio source at 5.7 GHz to realize that the EUV intensity of the expanding loop increased just before the radio source triggering. We reveal two EUV bidirectional flows that are linked with the start time of the loop expansion. Their positions were close to the radio source and propagated with velocities within a range of 30-117 km s-1.
Conclusions: We demonstrate that periodic regime of the electron acceleration in a model of the quasi-periodic magnetic reconnection might be able to explain physical properties and behavior of the sub-second pulsations. The depolarization process of the microwave emission might be caused by a plasma turbulence in the radio source. Finally, the observed EUV flows might be linked with reconnection outflows. Title: Chromospheric evaporation flows and density changes deduced from Hinode/EIS during an M1.6 flare Authors: Gömöry, P.; Veronig, A. M.; Su, Y.; Temmer, M.; Thalmann, J. K. Bibcode: 2016A&A...588A...6G Altcode: 2016arXiv160202145G
Aims: We study the response of the solar atmosphere during a GOES M1.6 flare using spectroscopic and imaging observations. In particular, we examine the evolution of the mass flows and electron density together with the energy input derived from hard X-ray (HXR) in the context of chromospheric evaporation.
Methods: We analyzed high-cadence sit-and-stare observations acquired with the Hinode/EIS spectrometer in the Fe xiii 202.044 Å (log T = 6.2) and Fe xvi 262.980 Å (log T = 6.4) spectral lines to derive temporal variations of the line intensity, Doppler shifts, and electron density during the flare. We combined these data with HXR measurements acquired with RHESSI to derive the energy input to the lower atmosphere by flare-accelerated electrons.
Results: During the flare impulsive phase, we observe no significant flows in the cooler Fe xiii line but strong upflows, up to 80-150 km s-1, in the hotter Fe xvi line. The largest Doppler shifts observed in the Fe xvi line were co-temporal with the sharp intensity peak. The electron density obtained from a Fe xiii line pair ratio exhibited fast increase (within two minutes) from the pre-flare level of 5.01 × 109 cm-3 to 3.16 × 1010 cm-3 during the flare peak. The nonthermal energy flux density deposited from the coronal acceleration site to the lower atmospheric layers during the flare peak was found to be 1.34 × 1010 erg s-1 cm-2 for a low-energy cut-off that was estimated to be 16 keV. During the decline flare phase, we found a secondary intensity and density peak of lower amplitude that was preceded by upflows of ~15 km s-1 that were detected in both lines. The flare was also accompanied by a filament eruption that was partly captured by the EIS observations. We derived Doppler velocities of 250-300 km s-1 for the upflowing filament material.
Conclusions: The spectroscopic results for the flare peak are consistent with the scenario of explosive chromospheric evaporation, although a comparatively low value of the nonthermal energy flux density was determined for this phase of the flare. This outcome is discussed in the context of recent hydrodynamic simulations. It provides observational evidence that the response of the atmospheric plasma strongly depends on the properties of the electron beams responsible for the heating, in particular the steepness of the energy distribution. The secondary peak of line intensity and electron density detected during the decline phase is interpreted as a signature of flare loops being filled by expanding hot material that is due to chromospheric evaporation.

A movie is available at http://www.aanda.org Title: Non-LTE Inversion of Spectropolarimetric and Spectroscopic Observations of a Small Active-region Filament Observed at the VTT Authors: Schwartz, P.; Balthasar, H.; Kuckein, C.; Koza, J.; Gömöry, P.; Rybák, J.; Kučera, A.; Heinzel, P. Bibcode: 2016ASPC..504..205S Altcode: An active region mini-filament was observed by VTT simultaneously in the He<small>I</small> 10 830 Å triplet by the TIP 1 spectropolarimeter, in Hα by the TESOS Fabry-Pérot interferometer, and in Ca <small>II</small> 8542 Å by the VTT spectrograph. The spectropolarimetric data were inverted using the HAZEL code and Hα profiles were modelled solving a NLTE radiative transfer in a simple isobaric and isothermal 2D slab irradiated both from bottom and sides. It was found that the mini-filament is composed of horizontal fluxtubes, along which the cool plasma of T∼10 000 K can flow by very large - even supersonic - velocities. Title: The CoMP-S Instrument at the Lomnický Peak Observatory: Status Report Authors: Kučera, A.; Ambróz, J.; Gömöry, P.; Habaj, P.; Kavka, J.; Kozák, M.; Schwartz, P.; Rybák, J.; Tomczyk, S.; Sewell, S.; Aumiller, P.; Summers, R.; Watt, A. Bibcode: 2016ASPC..504..321K Altcode: The Coronal Multi-channel Polarimeter for Slovakia (CoMP-S) has been installed at the high-altitude Lomnicky Peak Observatory of the Astronomical Institute of SAS (2633 m a.s.l.) in 2011. The instrument was designed and manufactured by HAO/NCAR (Boulder, USA) with a tunable Lyot filter and polarimeter for visible and near IR spectral regions. This instrument is proposed for coronagraphic observations of magnetic and velocity fields in the solar corona and in prominences. A fundamental upgrade of this instrument has been prepared with pair of cameras sensitive in the near IR spectral region in a new camera module. This upgrade is being incorporated to the instrument in course of the year 2014. In this contribution the technical parameters of the final configuration of the CoMP-S instrument containing four cameras, covering both visible and near IR spectral regions, are described. We also present a potential of the CoMP-S instrument for coronagraphic spectro-polarimetric observations of the solar corona and prominences with a capability for sequential measurements of the spectral profiles of all prominent emission lines in spectral region from 500 to 1100 nm. Title: Dual instrument for Flare and CME onset observations - Double solar Coronagraph with Solar Chromospheric Detector and Coronal Multi-channel Polarimeter at Lomnicky stit Observatory Authors: Kucera, Ales; Tomczyk, Steven; Rybak, Jan; Sewell, Scott; Gomory, Peter; Schwartz, Pavol; Ambroz, Jaroslav; Kozak, Matus Bibcode: 2015IAUGA..2246687K Altcode: We report on unique dual instrument developed for simultaneous measurements of velocity and magnetic fields in the solar chromosphere and corona. We describe the technical parameters and capability of the Coronal Multi-channel Polarimeter (CoMP-S) and Solar Chromospheric detector (SCD) mounted at the Double solar coronagraph at Lomnicky Stit Observatory and working simultaneously with strictly parallel pointing of both coronagraphs. The CoMP-S is 2D spectropolarimeter designed for observations of VIS and near-IR emission lines of prominences and corona with operating spectral range: 500 - 1100 nm, sequential measurement of several VIS and near-IR lines. Its field of view is 14 arcmin x 11 arcmin. It consists of 4-stage calcite Lyot filter followed by the ferro-liquid crystal polarizer and four cameras (2 visible, 2 infrared). The capability is to deliver 2D full Stokes I, Q, U, V, using registration with 2 IR cameras (line + background) and 2 VIS cameras (line + background) SCD is a single beam instrument to observe bright chromosphere. It is a combination of tunable filter and polarimeter. Spectral resolution of the SCD ranges from 0.046 nm for observations of the HeI 1083 nm line up to to 25 pm is for observation of the HeI 587.6 nm line. The birefringent filter of the SCD has high spectral resolution, as well as spatial resolution (1.7 arcseconds) and temporal resolution (10 seconds) First results are also reported and discussed. Title: Solar Magnetized Tornadoes: Rotational Motion in a Tornado-like Prominence Authors: Su, Yang; Gömöry, Peter; Veronig, Astrid; Temmer, Manuela; Wang, Tongjiang; Vanninathan, Kamalam; Gan, Weiqun; Li, YouPing Bibcode: 2014ApJ...785L...2S Altcode: 2013arXiv1312.5226S Su et al. proposed a new explanation for filament formation and eruption, where filament barbs are rotating magnetic structures driven by underlying vortices on the surface. Such structures have been noticed as tornado-like prominences when they appear above the limb. They may play a key role as the source of plasma and twist in filaments. However, no observations have successfully distinguished rotational motion of the magnetic structures in tornado-like prominences from other motions such as oscillation and counter-streaming plasma flows. Here we report evidence of rotational motions in a tornado-like prominence. The spectroscopic observations in two coronal lines were obtained from a specifically designed Hinode/EIS observing program. The data revealed the existence of both cold and million-degree-hot plasma in the prominence leg, supporting the so-called prominence-corona transition region. The opposite velocities at the two sides of the prominence and their persistent time evolution, together with the periodic motions evident in SDO/AIA dark structures, indicate a rotational motion of both cold and hot plasma with a speed of ~5 km s-1. Title: Inferring spectral characteristics of the Hα spectral line observed by the DOT Lyot filter Authors: Koza, J.; Rybák, J.; Gömöry, P.; Kučera, A. Bibcode: 2014CoSka..44...43K Altcode: A tunable Lyot filter can serve as a spectroscopic device rendering wide-field 2-D pseudospectroscopy of solar structures and follow-up crude reconstruction of a spectral line profile at each pixel within the field of view. We developed a method of inferring of the Doppler shift, the core intensity, the core width, and the core asymmetry of the Hα spectral line observed by the Lyot filter installed on the Dutch Open Telescope (DOT). The spectral characteristics are inferred through the fitting of five intensity samples, separated from each other by 0.35 Å, by a 4th-order polynomial, a Gaussian, and a parabola. We use the atlas Hα profile as a reference in estimating deviations of the derived spectral characteristics. The Gaussian is the most preferable means for measurements of the Doppler shift with deviations smaller than 1 km s-1. When using the 4th-order polynomial, deviations are within the interval ±2.5 km s-1, but it renders comparable deviations of the core intensity and the width as the Gaussian. The deviations are largely insensitive to the shape of the filter transmission, but depend mostly non-linearly on the Doppler shift. Therefore, they do not cancel out if the spectral characteristics are represented by their relative variations. Results can be used as corrections of spectral characteristics extracted from area-averaged Hα profiles acquired by the DOT Lyot filter. Title: The association between sunspot magnetic fields and superpenumbral fibrils Authors: Louis, R. E.; Balthasar, H.; Kuckein, C.; Gömöry, P.; Puschmann, K. G.; Denker, C. Bibcode: 2014AN....335..161L Altcode: 2013arXiv1312.1879L Spectropolarimetric observations of a sunspot were carried out with the Tenerife Infrared Polarimeter at Observatorio del Teide, Tenerife, Spain. Maps of the physical parameters were obtained from an inversion of the Stokes profiles observed in the infrared Fe I line at 15 648 Å. The regular sunspot consisted of a light bridge which separated the two umbral cores of the same polarity. One of the arms of the light bridge formed an extension of a penumbral filament which comprised weak and highly inclined magnetic fields. In addition, the Stokes V profiles in this filament had an opposite sign as the sunspot and some resembled Stokes Q or U. This penumbral filament terminated abruptly into another at the edge of the sunspot, where the latter was relatively vertical by about 30o. Chromospheric H\alpha and He II 304 Åfiltergrams revealed three superpenumbral fibrils on the limb-side of the sunspot, in which one fibril extended into the sunspot and was oriented along the highly inclined penumbral counterpart of the light bridge. An intense, elongated brightening was observed along this fibril that was co-spatial with the intersecting penumbral filaments in the photosphere. Our results suggest that the disruption in the sunspot magnetic field at the location of the light bridge could be the source of reconnection that led to the intense chromospheric brightening and facilitated the supply of cool material in maintaining the overlying superpenumbral fibrils. Title: Transmission profile of the Dutch Open Telescope Hα Lyot filter Authors: Koza, J.; Hammerschlag, R. H.; Rybák, J.; Gömöry, P.; Kučera, A.; Schwartz, P. Bibcode: 2014AN....335..409K Altcode: 2017arXiv171209253K Context Accurate knowledge of the spectral transmission profile of a Lyot filter is important, in particular in comparing observations with simulated data. The paper summarizes available facts about the transmission profile of the Dutch Open Telescope (DOT) Hα Lyot filter pointing to a discrepancy between sidelobe-free Gaussian-like profile measured spectroscopically and signatures of possible leakage of parasitic continuum light in DOT Hα images. We compute wing-to-center intensity ratios resulting from convolutions of Gaussian and square of the sinc function with the Hα atlas profile and compare them with the ratios derived from observations of the quiet Sun chromosphere at disk center. We interpret discrepancies between the anticipated and observed ratios and the sharp limb visible in the DOT Hα image as an indication of possible leakage of parasitic continuum light. A method suggested here can be applied also to indirect testing of transmission profiles of other Lyot filters. We suggest two theoretical transmission profiles of the DOT Hα Lyot filter which should be considered as the best available approximations. Conclusive answer can only be given by spectroscopic re-measurement of the filter. Title: Coronal Multi-channel Polarimeter at the Lomnicky Peak Observatory Authors: Schwartz, P.; Ambroz, J.; Gömöry, P.; Kozák, M.; Kučera, A.; Rybák, J.; Tomczyk, S.; Sewell, S.; Aumiller, P.; Summers, R.; Sutherland, L.; Watt, A. Bibcode: 2014IAUS..300..521S Altcode: Coronal Multi-channel Polarimeter (CoMP-S), developed by HAO/NCAR, has been introduced to regular operation at the Lomnicky Peak Observatory (High Tatras in northern Slovakia, 2633 m a.s.l.) of the Astronomical Institute of Slovak Academy of Sciences. We present here the technical parameters of the current version of the instrument and its potential for observations of prominences in the visual and near-IR spectral regions. The first results derived from observations of prominences in the Hα emission line taken during a coordinated observing campaign of several instruments in October 2012 are shown here. Title: Evidence of quiet-Sun chromospheric activity related to an emerging small-scale magnetic loop Authors: Gömöry, P.; Balthasar, H.; Puschmann, K. G. Bibcode: 2013A&A...556A...7G Altcode: 2013arXiv1306.3393G
Aims: We investigate the temporal evolution of magnetic flux emergence in the quiet-Sun atmosphere close to disk center.
Methods: We combined high-resolution SoHO/MDI magnetograms with TRACE observations taken in the 1216 Å channel to analyze the temporal evolution of an emerging small-scale magnetic loop and its traces in the chromosphere.
Results: We find signatures of flux emergence very close to the edge of a supergranular network boundary located at disk center. The new emerging flux appeared first in the MDI magnetograms in form of an asymmetric bipolar element, i.e., the patch with negative polarity is roughly twice as weak as the corresponding patch with opposite polarity. The average values of magnetic flux and magnetic flux densities reached 1.6 × 1018 Mx, - 8.5 × 1017 Mx, and 55 Mx cm-2, -30 Mx cm-2, respectively. The spatial distance between the opposite polarity patches of the emerged feature increased from about 2.″5 to 5.″0 during the lifetime of the loop, which was 36 min. A more precise lifetime-estimate of the feature was not possible because of a gap in the temporal sequence of the MDI magnetograms. The chromospheric response to the emerged magnetic dipole occurred ~9 min later than in the photospheric magnetograms. It consisted of a quasi-periodic sequence of time-localized brightenings visible in the 1216 Å TRACE channel for ~14 min that were co-spatial with the axis connecting the two patches of opposite magnetic polarity.
Conclusions: We identify the observed event as a small-scale magnetic loop emerging at photospheric layers that subsequently rose to the chromosphere. We discuss the possibility that the fluctuations detected in the chromospheric emission probably reflect magnetic-field oscillations which propagate to the chromosphere in the form of waves. Title: Search for Alfvén waves in a bright network element observed in Hα Authors: Koza, J.; Sütterlin, P.; Gömöry, P.; Rybák, J.; Kučera, A. Bibcode: 2013CoSka..43....5K Altcode: 2013arXiv1304.4027K Alfvén waves are considered as potential transporters of energy heating the solar corona. We seek spectroscopic signatures of the Alfvén waves in the chromosphere occupied by a bright network element, investigating temporal variations of the spectral width, intensity, Dopplershift, and the asymmetry of the core of the Hα spectral line observed by the tunable Lyot filter installed on the Dutch Open Telescope. The spectral characteristics are derived through the fitting of five intensity samples, separated from each other by 0.35 Å, by a 4th-order polynomial. The bright network element displays the most pronounced variations of the Dopplershift varying from 0 to 4 km s-1 about the average of 1.5 km s-1. This fact implies a persistent redshift of the Hα core with a redward asymmetry of about 0.5 km s-1, suggesting an inverse-C bisector. The variations of the core intensity up to ±10 % and the core width up to ±5 % about the respective averages are much less pronounced, but still detectable. The core intensity variations lag behind the Dopplershift variations about 2.1 min. The Hα core width tends to correlate with the Dopplershift and anticorrelate with the asymmetry, suggesting that more redshifted Hα profiles are wider and the broadening of the Hα core is accompanied with a change of the core asymmetry from redward to blueward. We also found a striking anticorrelation between the core asymmetry and the Dopplershift, suggesting a change of the core asymmetry from redward to blueward with an increasing redshift of the Hα core. The data and the applied analysis do not show meaningful tracks of Alfvén waves in the selected network element. Title: Properties of a Decaying Sunspot Authors: Balthasar, H.; Beck, C.; Gömöry, P.; Muglach, K.; Puschmann, K. G.; Shimizu, T.; Verma, M. Bibcode: 2013CEAB...37..435B Altcode: 2013arXiv1301.1562B A small decaying sunspot was observed with the Vacuum Tower Telescope (VTT) on Tenerife and the Japanese Hinode satellite. We obtained full Stokes scans in several wavelengths covering different heights in the solar atmosphere. Imaging time series from Hinode and the Solar Dynamics Observatory (SDO) complete our data sets. The spot is surrounded by a moat flow, which persists also on that side of the spot where the penumbra already had disappeared. Close to the spot, we find a chromospheric location with downflows of more than 10 km s^{-1} without photospheric counterpart. The height dependence of the vertical component of the magnetic field strength is determined in two different ways that yielded different results in previous investigations. Such a difference still exists in our present data, but it is not as pronounced as in the past. Title: A quiescent prominence observed in the Hα line by the COMP-S instrument at the Lomnický Peak Observatory Authors: Schwartz, P.; Rybák, J.; Kučera, A.; Kozák, M.; Ambróz, J.; Gömöry, P. Bibcode: 2012CoSka..42..135S Altcode: A prominence above the NEE limb was observed by the COMP-S instrument attached to the ZEISS coronagraph located at the Lomnický Peak Observatory. Observations were carried out on Nov 2, 2011 between 14:01:13 and 14:11:34 UT. The filter of the instrument was tuned during measurements sequentially in five wavelengths within the profile of the Hα line: 0, ±1, ±2 Å around 6563 Å. FWHM of the transmission function of the filter was ∼0.4Å at these wavelengths. Data were not absolutely calibrated, therefore they could be fitted using only a simple cloud model (1D geometry, a complete frequency redistribution, a source function independent of the optical depth) to diagnose the prominence plasma. As five wavelength points in the profile were not enough for an automatic fitting, five positions at the prominence were chosen for the analysis. Observed data from the five positions were simulated using the cloud model and groups of different models were found for each position. It means that the wavelength scale of a step as large as 1 Å when used for the Hα line is not fine enough for estimation of a correct and unique model. Simulating observations using three different finer wavelength scales it was found that the wavelength scale with a step of 0.3 Å and even more finer in the line core (step of 0.1 Å) is already suitable for more precise and unambiguous plasma diagnostics. We also show that for correct plasma diagnostics it is crucial to take into account an effect of a finite width of the transmission function of the filter. If observed data were fitted irrespectively of this important effect, an error in estimated model parameters could exceed even 100 %, except for the Doppler velocities, for which the error would be much smaller, e.g. for velocities up to 20 km s-1 the error is below 1 %. Title: Plasma Diagnostics of an EIT Wave Observed by Hinode/EIS and SDO/AIA Authors: Veronig, A. M.; Gömöry, P.; Kienreich, I. W.; Muhr, N.; Vršnak, B.; Temmer, M.; Warren, H. P. Bibcode: 2011ApJ...743L..10V Altcode: 2011arXiv1111.3505V We present plasma diagnostics of an Extreme-Ultraviolet Imaging Telescope (EIT) wave observed with high cadence in Hinode/Extreme-Ultraviolet Imaging Spectrometer (EIS) sit-and-stare spectroscopy and Solar Dynamics Observatory/Atmospheric Imaging Assembly imagery obtained during the HOP-180 observing campaign on 2011 February 16. At the propagating EIT wave front, we observe downward plasma flows in the EIS Fe XII, Fe XIII, and Fe XVI spectral lines (log T ≈ 6.1-6.4) with line-of-sight (LOS) velocities up to 20 km s-1. These redshifts are followed by blueshifts with upward velocities up to -5 km s-1 indicating relaxation of the plasma behind the wave front. During the wave evolution, the downward velocity pulse steepens from a few km s-1 up to 20 km s-1 and subsequently decays, correlated with the relative changes of the line intensities. The expected increase of the plasma densities at the EIT wave front estimated from the observed intensity increase lies within the noise level of our density diagnostics from EIS Fe XIII 202/203 Å line ratios. No significant LOS plasma motions are observed in the He II line, suggesting that the wave pulse was not strong enough to perturb the underlying chromosphere. This is consistent with the finding that no Hα Moreton wave was associated with the event. The EIT wave propagating along the EIS slit reveals a strong deceleration of a ≈ -540 m s-2 and a start velocity of v 0 ≈ 590 km s-1. These findings are consistent with the passage of a coronal fast-mode MHD wave, pushing the plasma downward and compressing it at the coronal base. Title: The LSO/KSO Hα prominence catalogue: cross-calibration of data Authors: Rybák, J.; Gömöry, P.; Mačura, R.; Kučera, A.; Rušin, V.; Pötzi, W.; Baumgartner, D.; Hanslmeier, A.; Veronig, A.; Temmer, M. Bibcode: 2011CoSka..41..133R Altcode: We present work on the extension of the homogeneous prominence catalogue created for the epoch 1967 — 2009 at the Lomnicky Peak Observatory (LSO) by incorporating new data acquired at the Kanzelhöhe Observatory for Solar and Environmental Research (KSO). We use data of 20 Hα prominences observed almost simultaneously at both observatories during four days in August/September 2009 to analyze the significance of differences of the determined parameters used in the Hα prominence catalogue. A reduction of the data from KSO and adaptation of the resulting parameters to fit the parameters of the LSO catalogue confirm that no special homogenization is needed to create a common catalogue data set. Thus, we justified that the LSO catalogue could be extended onward in the future using a more comprehensive database of observations from KSO. Title: Spectroscopic Observations of a Coronal Moreton Wave Authors: Harra, Louise K.; Sterling, Alphonse C.; Gömöry, Peter; Veronig, Astrid Bibcode: 2011ApJ...737L...4H Altcode: We observed a coronal wave (EIT wave) on 2011 February 16, using EUV imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and EUV spectral data from the Hinode/EUV Imaging Spectrometer (EIS). The wave accompanied an M1.6 flare that produced a surge and a coronal mass ejection (CME). EIS data of the wave show a prominent redshifted signature indicating line-of-sight velocities of ~20 km s-1 or greater. Following the main redshifted wave front, there is a low-velocity period (and perhaps slightly blueshifted), followed by a second redshift somewhat weaker than the first; this progression may be due to oscillations of the EUV atmosphere set in motion by the initial wave front, although alternative explanations may be possible. Along the direction of the EIS slit the wave front's velocity was ~500 km s-1, consistent with its apparent propagation velocity projected against the solar disk as measured in the AIA images, and the second redshifted feature had propagation velocities between ~200 and 500 km s-1. These findings are consistent with the observed wave being generated by the outgoing CME, as in the scenario for the classic Moreton wave. This type of detailed spectral study of coronal waves has hitherto been a challenge, but is now possible due to the availability of concurrent AIA and EIS data. Title: Heating of the quiet solar corona from measurements of the FET/TESIS instrument on-board the KORONAS-FOTON satellite Authors: Rybák, J.; Gömöry, P.; Benz, A.; Bogachev, P.; Brajša, R. Bibcode: 2010nspm.conf..107R Altcode: The paper presents the first results of the observations of time evolution of the quiet solar corona brightenings obtained due to very rapid photography of the corona with full-disk EUV telescopes of the FET/TESIS instrument onboard the KORONA FOTON satellite. The measurements were performed simultaneously in the emission of the Fe IX / X 17.1 and Fe VIII 13.1 spectral lines with 10 second temporal cadence and spatial scale of 1.7 arc seconds within one hour. This test observation, carried out on 15 July 2009, was analyzed in order to determine whether this type of observation can be used to identify individual microevents in the solar corona heating that are above the tresholds of spatial and temporal resolutions of the observations of non-active regions in the solar atmosphere. For this purpose, a simple method was used involving cross-correlation of the plasma emission time evolution at different temperatures, each time from observations of identical elements. The results obtained are confronted with the expected observable manifestations of the corona heating via nanoflares. TESIS is a set of instruments for the Sun photography developed in the Lebedev Physics Institute of the Russian Academy of Sciences that was launched into orbit in January 2009. Title: Koronálny multikanálový polarimeter pre observatórium Lomnický štít Title: Koronálny multikanálový polarimeter pre observatórium Lomnický štít Title: Coronal multichannel polarimeter for Lomnický štít Observatory. Authors: Rybák, J.; Ambróz, J.; Gömöry, P.; Kozák, M.; Kučera, A.; Tomczyk, S.; Sewell, S.; Summers, R.; Sutherland, L.; Watt, A. Bibcode: 2010nspm.conf..196R Altcode: The contribution presents the process of development and preparation of the Coronal Multi-channel Polarimeter (COMP-S) for the Lomnický štít Observatory of the SAS Astronomy Institute. The design of the device is based on the experience gained in recent years with the CoMP (High Altitude Observatory / NCAR; Boulder, USA) instrument. The device will be a combination of two main optical components: the Lyot tunable filter and polarimeter, and is prepared specifically for one of the 20 cm Zeiss coronagraph at the Lomnický štít Observatory where it will be installed in 2011. CoMP-S will differ from its predecessor in several respects. The most important difference is that CoMP-S will be able to observe the corona and chromospheric emission lines in the wavelength range from 530 to 1083 nm. This feature will be achieved using superachromatic wave plates and dichroic polarizers with wide bandwidth. Furthermore, in the CoMP-S instrument new SWIFT liquid crystals of Meadowlark Optics company will be used as variable retarders instead of nematic liquid crystal retarders (LCVR) which will considerably shorten the measuring process. Ferroelectric liquid crystals will provide measurements of the full Stokes vector with nearly optimal polarization throughout the whole instrument bandwidth. Recently developed sCMOS cameras are to provide diffraction limit resolution of observations, with the 860x680 arc second field and 30-frames-per-second cadence. The device will be used in the Astronomical Observatory of SAS at Lomnický štít primarily for spectrum polarimetry of prominences and coronal loops of the active solar regions. Title: Slnečná aktivita a kozmické 'iarenie: magnetické pole Slnka a úroveň kozmického žiarenia Title: Slnečná aktivita a kozmické 'iarenie: magnetické pole Slnka a úroveň kozmického žiarenia Title: Solar activity and cosmic radiation: Sun's magnetic field and cosmic radiation levels. Authors: Bodnárová, M.; Rybák, J.; Gömöry, P.; Kudela, K. Bibcode: 2010nspm.conf..175B Altcode: In this work we have analyzed the correlation of the Sun's magnetic activity and cosmic radiation levels during the period 1951-2004. As a solar magnetic activity indicator, affecting the cosmic radiation, we have chosen open magnetic field configurations which we characterized by an open magnetic flux factor (OMFF). The OMFF was calculated from the intensity measurements of the green coronal line. In calculations leading to the relation between the OMFF and galactic cosmic radiation (GCR) levels the cross-correlation of these datasets was used. The goal of this contribution was to find mainly time-dependent changes in the evolution of the OMFF and GCR correlation. In order to do so,besides the correlation calculations based on the long time series of the OMFF and GCR data covering the entire period 1951-2004 we have also calculated the correlation of the OMFF and GCR data from shorter periods (180 days). We have found that the cross-correlation evolution varies depending on the phase of the solar cycle. During the minimum the evolution is characterized by conspicuous periodicity with a period ~ 14 days and the cross-correlation function takes statistically significant values. During the maximum the period of the variations is not clear and the cross-correlation function takes low values that are not statistically significant. Title: Multiwavelength Imaging and Spectroscopy of Chromospheric Evaporation in an M-class Solar Flare Authors: Veronig, A. M.; Rybák, J.; Gömöry, P.; Berkebile-Stoiser, S.; Temmer, M.; Otruba, W.; Vršnak, B.; Pötzi, W.; Baumgartner, D. Bibcode: 2010ApJ...719..655V Altcode: 2010arXiv1007.0930V We study spectroscopic observations of chromospheric evaporation mass flows in comparison with the energy input by electron beams derived from hard X-ray (HXR) data for the white-light M2.5 flare of 2006 July 6. The event was captured in high-cadence spectroscopic observing mode by SOHO/CDS combined with high-cadence imaging at various wavelengths in the visible, extreme ultraviolet, and X-ray domain during the joint observing campaign JOP171. During the flare peak, we observe downflows in the He I and O V lines formed in the chromosphere and transition region, respectively, and simultaneous upflows in the hot coronal Si XII line. The energy deposition rate by electron beams derived from RHESSI HXR observations is suggestive of explosive chromospheric evaporation, consistent with the observed plasma motions. However, for a later distinct X-ray burst, where the site of the strongest energy deposition is exactly located on the Coronal Diagnostics Spectrometer (CDS) slit, the situation is intriguing. The O V transition region line spectra show the evolution of double components, indicative of the superposition of a stationary plasma volume and upflowing plasma elements with high velocities (up to 280 km s-1) in single CDS pixels on the flare ribbon. However, the energy input by electrons during this period is too small to drive explosive chromospheric evaporation. These unexpected findings indicate that the flaring transition region is much more dynamic, complex, and fine structured than is captured in single-loop hydrodynamic simulations. Title: Magnetic loop emergence within a granule Authors: Gömöry, P.; Beck, C.; Balthasar, H.; Rybák, J.; Kučera, A.; Koza, J.; Wöhl, H. Bibcode: 2010A&A...511A..14G Altcode: 2009arXiv0910.4449G
Aims: We investigate the temporal evolution of magnetic flux emerging within a granule in the quiet-Sun internetwork at disk center.
Methods: We combined IR spectropolarimetry of high angular resolution performed in two Fe i lines at 1565 nm with speckle-reconstructed G-band imaging. We determined the magnetic field parameters by a LTE inversion of the full Stokes vector using the SIR code, and followed their evolution in time. To interpret the observations, we created a geometrical model of a rising loop in 3D. The relevant parameters of the loop were matched to the observations where possible. We then synthesized spectra from the 3D model for a comparison to the observations.
Results: We found signatures of magnetic flux emergence within a growing granule. In the early phases, a horizontal magnetic field with a distinct linear polarization signal dominated the emerging flux. Later on, two patches of opposite circular polarization signal appeared symmetrically on either side of the linear polarization patch, indicating a small loop-like structure. The mean magnetic flux density of this loop was roughly 450 G, with a total magnetic flux of around 3 × 1017 Mx. During the ~12 min episode of loop occurrence, the spatial extent of the loop increased from about 1 to 2 arcsec. The middle part of the appearing feature was blueshifted during its occurrence, supporting the scenario of an emerging loop. There is also clear evidence for the interaction of one loop footpoint with a preexisting magnetic structure of opposite polarity. The temporal evolution of the observed spectra is reproduced to first order by the spectra derived from the geometrical model. During the phase of clearest visibility of the loop in the observations, the observed and synthetic spectra match quantitatively.
Conclusions: The observed event can be explained as a case of flux emergence in the shape of a small-scale loop. The fast disappearance of the loop at the end could possibly be due to magnetic reconnection. Title: Multi-wavelength fine structure and mass flows in solar microflares Authors: Berkebile-Stoiser, S.; Gömöry, P.; Veronig, A. M.; Rybák, J.; Sütterlin, P. Bibcode: 2009A&A...505..811B Altcode: Aims: We study the multi-wavelength characteristics at high spatial resolution, as well as chromospheric evaporation signatures of solar microflares. To this end, we analyze the fine structure and mass flow dynamics in the chromosphere, transition region and corona of three homologous microflares (GOES class <A9/0.7 with/without background), which occurred on July 4, 2006 in AR 10898.
Methods: A multi-wavelength analysis using temporally and spatially highly resolved imaging data from the Dutch open telescope (Hα, Ca ii H), the transition region and coronal explorer (17.1 nm), the extreme-ultraviolet imaging telescope (19.5 nm), and the Reuven Ramaty high energy solar spectroscopic imager (≳3 keV) was carried out. EUV line spectra provided by the coronal diagnostic spectrometer are searched for Doppler shifts in order to study associated plasma flows at chromospheric (He i, T∼3.9× 104 K), transition region (e.g. O v, T∼ 2.6× 105 K), and coronal temperatures (Si xii, T∼ 2× 106 K). RHESSI X-ray spectra provide information about non-thermal electrons.
Results: The multi-wavelength appearance of the microflares is in basic agreement with the characteristics of large flares. For the first event, a complex flare sequence is observed in TRACE 17.1 nm images (T≈ 1 MK), which show several brightenings, narrow loops of enhanced emission, and an EUV jet. EIT 19.5 nm data (T≈ 1.5 MK) exhibit similar features for the third event. DOT measurements show finely structured chromospheric flare brightenings for all three events, loop-shaped fibrils of increased emission between Hα brightenings, as well as a similar feature in Ca ii. For all three events, a RHESSI X-ray source (3-8 keV, T ≳ 10 MK) is located in between two chromospheric brightenings situated in magnetic flux of opposite polarity. We find the flow dynamics associated with the events to be very complex. In the chromosphere and transition region, CDS observed downflows for the first (v ≲ 40 km s-1), and upflows for the second event (v ≲ 40 km s-1). During the third microflare, we find upflows of ≲ 20 km s-1 and also weak downflows of ≲20 km s-1 in two separate brightenings. For all three microflares, multi-component fitting is needed for several profiles of He i, O v, and Ne vi lines observed at the flare peaks, which indicate spatially unresolved, oppositely directed flows of ≲180 km s-1. We interpret these flows as twisting motions of the flare loops. Loop-shaped fibrils in between Hα brightenings showing opposite flow directions (v≈5 km s-1) are also observed in DOT Hα Dopplergrams. RHESSI X-ray spectra show evidence of non-thermal bremsstrahlung for two of the three microflares. The electron beam flux density deposited in the chromosphere for these events is estimated to straddle the threshold heating flux between gentle and explosive evaporation.

Appendix A and the movie are only available in electronic form at http://www.aanda.org Title: The three-dimensional structure of the magnetic field of a sunspot Authors: Balthasar, Horst; Gömöry, Peter Bibcode: 2009IAUS..259..225B Altcode: Spectro-polarimetric observations in several spectral lines allow to determine the height variation of the magnetic field of a small sunspot throughout the solar photosphere. The full Stokes-vector is measured with high spatial resolution. From these data we derive the magnetic field vector. The magnetic field strength decreases with height everywhere in the spot, even in the outer penumbra where some other authors have reported the opposite. The precise value of this decrease depends on the exact position in the spot. Values vary between 0.5 and 2.2 G km-1 when they are determined from an iron and a silicon line in the near infrared. The magnetic field is less inclined in the higher layers where the silicon line is formed. Once the magnetic vector field is known, it is straight forward to determine current densities and helicities. Current densities exhibit a radial structure in the penumbra, although it is still difficult to correlate this with the structure seen in the intensity continuum. In spite of this, current densities have a potential to serve as diagnostic tools to understand the penumbra, at least with the spatial resolution of the upcoming telescopes. The mean infered helicity is negative, as expected for a spot in the northern hemisphere. Nevertheless, there are locations inside the spot with positive helicity. Title: Observations of Chromospheric Evaporation Flows in RHESSI Microflares Authors: Berkebile-Stoiser, S.; Gömöry, P.; Veronig, A.; Rybák, J. Bibcode: 2009CEAB...33..169B Altcode: We present the analysis of two homologous microflares of GOES class A9 with respect to mass flows in the chromosphere and transition region. Both events show non-thermal emission (evidence for beamed electrons) in RHESSI X-ray spectra. As outlined by observations of the Coronal Diagnostic Spectrometer, we find for the first event downflows in the He I, O V and Ne VI line reaching speeds up to 40 km s^{-1} at the position of chromospheric flare brightenings. On the other hand, upflows with velocities ≲40 km^{-1} are observed for the second microflare.

According to hydrodynamic flare simulations, the non-thermal electron energy density F deposited in the chromosphere determines if chromospheric evaporation is `gentle' or `explosive'. Thus, we derive rough estimates for F in our microflares and compare the results to the observed CDS flow properties. Title: Multi-wavelength Observations of Microflares Near an Active Region Authors: Bein, B.; Veronig, A.; Rybak, J.; Gömöry, P.; Berkebile-Stoiser, S.; Sütterlin, P. Bibcode: 2009CEAB...33..179B Altcode: We study the multi-wavelength characteristics of a microflaring active region (AR 10898) near disc centre. The analysed data were from the 4^{th} of July 2006, and were recorded by DOT (Hα, Ca II H), RHESSI (X-rays), TRACE (EUV) and SOHO/MDI (magnetograms). The identified microflare events were studied with respect to their magnetic field configuration and their multi-wavelength time evolution. Title: Solar Convection and Oscillation Interaction Authors: Hanslmeier, A.; Kučera, A.; Rybák, J.; Wöhl, H.; Gömöry, P. Bibcode: 2009CEAB...33...51H Altcode: In this paper we investigate bisectors of solar photospheric lines. The bisectors reflect vertical velocity gradients over the height of line formation and therefore reveal important information about the dynamics in these layers. Their shape and shift is influenced by (a) convective motions, (b) oscillatory motions that can act differently at different photospheric heights. The bisectors are selected from different locations that show mainly a granular evolution or an intergranular evolution. Two selection criteria were applied: continuum intensity (enhanced for granular bisectors, reduced for intergranular bisectors), and full width at half maximum values (enhanced for intergranular bisectors). The results demonstrate how oscillatory motions influence the bisectors as a whole. In the example given a smaller amplitude of oscillations over intergranular areas is indicated. Title: The three-dimensional structure of sunspots. I. The height dependence of the magnetic field Authors: Balthasar, H.; Gömöry, P. Bibcode: 2008A&A...488.1085B Altcode: Aims: We investigate the height dependence of the magnetic field of a sunspot, which has been until now a controversial issue.
Methods: Full-Stokes profiles of a sunspot, derived from infrared spectro-polarimetric measurements, were investigated. The magnetic field strength, inclination and azimuth were obtained using an inversion code. The results from two different spectral lines deliver the height dependence of the magnetic vector field. Vertical current densities and helicities as well as the vertical derivative of the vertical component of the magnetic field strength are calculated using Maxwell's equations.
Results: Inside the spot, the total magnetic field strength decreases with height, even in the outer penumbra, where the opposite trend was reported by other investigators. Outside the spot, the field strength increases with height apart from at a few small locations. This result is interpreted in terms of magnetic canopies. Magnetic field lines are less inclined in higher layers everywhere in the field of view. In the umbra, the vertical component of the magnetic field decreases by values in the range 0.5-2.2 G km-1, depending on the applied method. Mean values in the inner penumbra are smaller than in the umbra. In the outer penumbra, the vertical magnetic component increases independently of the local intensity distribution. A pore close to the spot exhibits a more rapid decrease with height than the spot itself. The electric current densities and helicities depend on the fine structure of the sunspots. Typical values of the current densities vary in the range ±40 mA m-2. The mean values are -11 mA m-1 for the umbra and -2 mA m-1 for the penumbra, respectively, but the propagated errors are of the same order as the mean values. There are indications that the radial structure of the penumbra is related to enhanced current densities, but at the present resolution we are unable to establish a correlation with local intensity fluctuations.
Conclusions: If the spatial resolution is sufficiently high, electric current densities and helicities could be applied as reliable diagnostic tools for understanding penumbral fine structure. Title: Multi-wavelength Observations of Dynamic Fibrils in the Upper Photosphere and Chromosphere Authors: Kucera, A.; Beck, Ch.; Gomory, P.; Koza, J.; Woehl, H.; Rybak, J. Bibcode: 2008ESPM...12.2.52K Altcode: Spatial and temporal evolution of dynamic fibrils (DF) as well as coupling with photospheric features was investigated.

The main target were remnants in the active region 10997 on May 28, 2008. We used about 1 hour series of multi wavelength simultaneous observations of the DFs and corresponding photospheric features. The observations were performed with the german Vacuum Tower Telescope equipped with several post-focus instruments. Namely: TESOS (Triple Etalon SOlar Spectrometer) instrument was used in polarimetric mode (VIP=Visual Imaging Polarimeter) to register 2D spectra of the DFs in H-alpha line and in magnetically sensitive Fe I 630.2 nm line. TIP (Tenerife Infrared Polarimeter) mounted on the Echelle spectrograph was used for spectropolarimetric observations of two neutral iron lines at 1.56 micrometers. We scanned 2D area 80" x 5", producing thus 2D maps of intensity, velocity and magnetic field of the low photosphere under the chromospheric fibril field.

Additionally G-band and H-alpha images were registered with high cadence and the supporting data from the TRACE satellite (17.1 nm, WL, Lyman alpha line and 160 nm continuum) are also available. After careful spatial coalignment of 2D maps we first selected numerous DFs in the H-alpha images. Then we investigated temporal evolution of those DFs concerning changes of their dimensions, positions and fluctuations and correlated these characteristics with temporal evolution of the intensities, velocities and magnetic field characteristics observed in the spatially corresponding photosphere. The poster demonstrates the complex observations, data reduction and coalignment and preliminary results on coupling between DFs and underlying photospheric features. Title: Acceleration in Fast Halo CMEs and Synchronized Flare HXR Bursts Authors: Temmer, M.; Veronig, A. M.; Vršnak, B.; Rybák, J.; Gömöry, P.; Stoiser, S.; Maričić, D. Bibcode: 2008ApJ...673L..95T Altcode: We study two well-observed, fast halo CMEs, covering the full CME kinematics including the initiation and impulsive acceleration phase, and their associated flares. We find a close synchronization between the CME acceleration profile and the flare energy release as indicated by the RHESSI hard X-ray flux onsets, as well as peaks occur simultaneously within 5 minutes. These findings indicate a close physical connection between both phenomena and are interpreted in terms of a feedback relationship between the CME dynamics and the reconnection process in the current sheet beneath the CME. Title: Propagating Waves in the Chromospheric Network Authors: Gömöry, P.; Rybák, J.; Kučera, A.; Curdt, W.; Wöhl, H. Bibcode: 2007ASPC..368..133G Altcode: Wave modulation of ultraviolet emissions originated in and above quiet chromospheric network is studied. In particular, cross-correlation, wavelet analysis and phase difference analysis of the intensities as well as the Doppler shifts of emission lines of He I 584.33 Å (chromosphere), O V 629.73 Å (transition region) and Mg IX 368.07 Å (corona) are employed to study waves at different heights and their direction of propagation. The results are interpreted as evidence of compressive waves that propagate downward from the transition region to the chromosphere in the observed chromospheric network. Different scenarios regarding the origin and source localization of these waves are discussed. Title: Magnetic vector field above a sunspot Authors: Gömöry, P.; Balthasar, H. Bibcode: 2007msfa.conf..221G Altcode: We present an analysis of the spectro-polarimetricmeasurements of the active region NOAA 10886 taken with the Tenerife Infrared Polarimeter in the Fe I 10783 Å spectral line. The magnetic field strength and the magnetic inclination and azimuth were inferred from the data using the inversion code SIR. The vertical current densities and the vertical derivative of the vertical component of the magnetic field were then calculated for the leading spot of the AR 10886. We revealed that typical values of the vertical current densities vary in the range ± 40mAm-2 inside the spot. Moreover, we found an extended area of enhanced vertical current densities in the umbra (values up to -80mAm-2). Our analysis also showed that the vertical component of the magnetic field strength decreases by 0.6 - 1.6Gkm-1 and 0.5 - 0.8Gkm-1 in the umbra and inner penumbra; on the other hand we found an increase of the vertical component of the magnetic field in the outer penumbra (typical values varying between 0.1 - 0.5Gkm-1). Title: Multi-Wavelength Observations with High Resolution of a M5.4 Flare from Ground and Space Authors: Kucera, A.; Wöhl, H.; Rybák, J.; Gömöry, P.; Veronig, A. Bibcode: 2006ESASP.617E..68K Altcode: 2006soho...17E..68K No abstract at ADS Title: SOHO/CDS observations of waves above the network Authors: Gömöry, P.; Rybák, J.; Kučera, A.; Curdt, W.; Wöhl, H. Bibcode: 2006A&A...448.1169G Altcode: We analyze temporal variations in the intensities and the Doppler shifts of He i 584.33 Å (chromosphere), O v 629.73 Å (transition region), and Mg ix 368.07 Å (corona) measured in and above chromospheric network near disk center with the Coronal Diagnostic Spectrometer (CDS) onboard the Solar and Heliospheric Observatory (SOHO). There is significant correlation between the He i and O v modulations, with O v intensity leading He i intensity by 27.3 s ± 4.6 s but no significant time shift in the Doppler shift. Cross-correlation between the O v and Mg ix intensities reveals multiple maxima without correlation between their Doppler shifts. Wavelet power analysis gives evidence of intermittent chromospheric and transition-region oscillations with periodicities in the 250-450 s range and of coronal oscillations in the 110-300 s range. Wavelet phase difference analysis shows that the determined time shift between variations of the He i and O v intensities is dominated by waves with about 300 s periodicity. We interpret these results as giving evidence of compressive waves that propagate downward from the transition region to the chromosphere in the particular chromospheric network. We discuss different scenarios regarding origin and source localization of waves, and we speculate on their role in coronal heating above chromospheric network. Title: Analysis of Dynamics of Loops in AN Active Region Associated with a Small C-Class Flare Authors: Gömöry, P.; Rybák, J.; Kucera, A.; Wöhl, H. Bibcode: 2005ESASP.596E..56G Altcode: 2005ccmf.confE..56G No abstract at ADS Title: Analysis of Doppler Shifts of Spectral Lines Obtained by the CDS/SOHO Instrument Authors: Gömöry, P.; Rybák, J.; Kučera, A.; Curdt, W.; Wöhl, H. Bibcode: 2005ASSL..320..203G Altcode: 2005smp..conf..203G No abstract at ADS Title: Variability and Dynamics of the Outer Atmospheric Layers in the Quiet Solar Network Authors: Gömöry, P.; Rybák, J.; Kučera, A.; Curdt, W.; Wöhl, H. Bibcode: 2005HvaOB..29...71G Altcode: A detailed study of the temporal evolution of the chromospheric He I 584.33 Å and the transition region O V 629.73 Å emission line intensities of quiet supergranular network of the Sun near disk centre observed with Coronal Diagnostic Spectrometer (CDS) is presented. A wavelet analysis of the 1729 s (28.8 min) long temporal series was performed in order to derive the duration as well as periods of the chromospheric and the transition region oscillations. The He I line intensities show significant power for periods around 300 s (3.3 mHz), which is relevant only in the second half of the observing sequence (between 800 -- 1700 s). The temporal evolution corresponding to the O V line intensities shows strong power around the period of 400 s (2.5 mHz), which is significant during the whole observing sequence as well as the oscillation of lower power for periods of around 250 s (4.0 mHz), which is present only in the middle of the observing sequence (between 700 -- 1300 s). Title: High Resolution Observations of a M5.4 Flare Authors: Kučera, A.; Wöhl, H.; Rybák, J.; Gömöry, P.; Tomasz, F. Bibcode: 2005HvaOB..29..177K Altcode: Hα observations of a M5.4 flare taken in the active region NOAA 10646 with the Vacuum Tower Telescope at Observatório del Teide, Tenerife, on July 13, 2004 are presented. The temporal evolution of the area of the flare and its morphological changes are investigated and discussed. Simultaneous observations of the flare in EUV lines taken with CDS/SOHO instrument are shown and additional data from GOES-10 instrument are compared. Title: Dynamics of the Quiet Upper Solar Atmosphere in the Network Authors: Gömöry, P.; Rybák, J.; Kucera, A.; Curdt, W.; Wöhl, H. Bibcode: 2004ESASP.575..400G Altcode: 2004soho...15..400G No abstract at ADS Title: On Mutual Relation Among the Outer Atmospheric Layers in Network: SOHO/CDS Study Authors: Gömöry, P.; Rybák, J.; Kucera, A.; Curdt, W.; Wöhl, H. Bibcode: 2004ESASP.547..303G Altcode: 2004soho...13..303G SOHO/CDS measurements of emission in the network of the quiet solar atmosphere near disk center were used to derive mutual relations of emission and dynamics in different temperature regimes in/above supergranular network. Cross-correlation functions of the line intensities and the Doppler shifts of the chromospheric line He I 584.3 Å, the transition region line O V 629.7 Å and the coronal line Mg IX 396.1 Å were calculated in order to study relative variability of different atmospheric layers. Relatively high correlations were found between the intensities and the Doppler shifts of the He I and O V lines with two peaks of the intensity correlation function. The maximum value of the correlation of intensities (CC = 0.86) was reached for the zero time lag and the second maximum (CC = 0.78) was obtained for the time lag -190s (O V precedes He I). Only one sharp peak (CC = 0.55) was detected in the Doppler shift correlation function of these lines for the zero time lag. For the correlation of O V and Mg IX intensities one peak (CC = 0.57) of the correlation function was also discovered for the time lag +150s (Mg IX falls behind O V). In contrast, no correlation was obtained for the Doppler shifts of the O V and Mg IX lines. Summarizing we can assume clear relation in energy transfer and/or mass motion between chromosphere and transition region but no relation was found between corona and the lower parts of the solar atmosphere above the particular network under study. Title: Transition region eruptive event observed with SOHO/CDS in the quiet Sun network Authors: Gömöry, P.; Rybák, J.; Kučera, A.; Curdt, W.; Wöhl, H. Bibcode: 2003HvaOB..27...67G Altcode: CDS observations of the quiet Sun network in the chromospheric He I 584.33 Å and transition region O V 629.73 Å emission lines over a time period of ∼ 29 min are presented. One eruptive event was detected in this time series of data. The parameters of the network eruptive event are derived and the type of this small-scale activity is identified. The lifetime of the event was ∼ 1 min and it was found only in the transition region emission line. This event had no chromospheric counterpart. All O V spectral profiles of the eruptive event were blueshifted and the maximal Doppler shift was -14.7 km s-1. During an initial phase of the eruptive event, the O V intensity enhancement factor was 2.3. These parameters indicate that the observed event could be a transition region explosive event but measured with the limited resolution of the CDS instrument.