Author name code: robustini ADS astronomy entries on 2022-09-14 author:"Robustini, Carolina" ------------------------------------------------------------------------ Title: COCOPLOT: COlor COllapsed PLOTting software Using colour to view 3D data as a 2D image Authors: Druett, Malcolm K.; Pietrow, Alexander G. M.; Vissers, Gregal J. M.; Robustini, Carolina; Calvo, Flavio Bibcode: 2022RASTI...1...29D Altcode: 2021arXiv211110786D Most modern solar observatories deliver data products formatted as 3D spatio-temporal data cubes, that contain additional, higher dimensions with spectral and/or polarimetric information. This multi-dimensional complexity presents a major challenge when browsing for features of interest in several dimensions simultaneously. We developed the COlor COllapsed PLOTting (COCOPLOT) software as a quick-look and context image software, to convey spectral profile or time evolution from all the spatial pixels ($x,y$) in a 3D [$n_x,n_y,n_\lambda$] or [$n_x,n_y,n_t$] data cube as a single image, using color. This can avoid the need to scan through many wavelengths, creating difference and composite images when searching for signals satisfying multiple criteria. Filters are generated for the red, green, and blue channels by selecting values of interest to highlight in each channel, and their weightings. These filters are combined with the data cube over the third dimension axis to produce an $n_x \times n_y \times 3$ cube displayed as one true color image. Some use cases are presented for data from the Swedish 1-m Solar Telescope (SST) and IRIS, including H$\alpha$ solar flare data, a comparison with $k$-means clustering for identifying asymmetries in the Ca II K line and off-limb coronal rain in IRIS C II slit-jaw images. These illustrate identification by color alone using COCOPLOT of locations including line wing or central enhancement, broadening, wing absorption, and sites with intermittent flows or time-persistent features. COCOPLOT is publicly available in both IDL and Python. Title: COCOPLOT: COlor COllapsed PLOTting software Authors: Druett, Malcolm K.; Pietrow, Alexander G. M.; Vissers, Gregal J. M.; Robustini, Carolina Bibcode: 2021ascl.soft11008D Altcode: The COCOPLOT (COlor COllapsed PLOTting) quick-look and context image code conveys spectral profile information from all of the spatial pixels in a 3D datacube as a single image using color. It can also identify and expose temporal behavior and display and highlight solar features. COCOPLOT thus aids in identifying regions of interest quickly. The software is available in Python and IDL, and can be used as a standalone package or integrated into other software. Title: Three-dimensional magnetic field structure of a flux-emerging region in the solar atmosphere Authors: Yadav, Rahul; de la Cruz Rodríguez, Jaime; Díaz Baso, Carlos José; Prasad, Avijeet; Libbrecht, Tine; Robustini, Carolina; Asensio Ramos, Andrés Bibcode: 2019A&A...632A.112Y Altcode: 2019arXiv191013279Y We analyze high-resolution spectropolarimetric observations of a flux-emerging region (FER) in order to understand its magnetic and kinematic structure. Our spectropolarimetric observations in the He I 10830 Å spectral region of a FER were recorded with GRIS at the 1.5 m aperture GREGOR telescope. A Milne-Eddington-based inversion code was employed to extract the photospheric information of the Si I spectral line, whereas the He I triplet line was analyzed with the Hazel inversion code, which takes into account the joint action of the Hanle and the Zeeman effects. The spectropolarimetric analysis of the Si I line reveals a complex magnetic structure near the vicinity of the FER, where a weak (350-600 G) and horizontal magnetic field was observed. In contrast to the photosphere, the analysis of the He I triplet presents a smooth variation of the magnetic field vector (ranging from 100 to 400 G) and velocities across the FER. Moreover, we find supersonic downflows of ∼40 km s-1 appearing near the foot points of loops connecting two pores of opposite polarity, whereas strong upflows of 22 km s-1 appear near the apex of the loops. At the location of supersonic downflows in the chromosphere, we observed downflows of 3 km s-1 in the photosphere. Furthermore, nonforce-free field extrapolations were performed separately at two layers in order to understand the magnetic field topology of the FER. We determine, using extrapolations from the photosphere and the observed chromospheric magnetic field, that the average formation height of the He I triplet line is ∼2 Mm from the solar surface. The reconstructed loops using photospheric extrapolations along an arch filament system have a maximum height of ∼10.5 Mm from the solar surface with a foot-point separation of ∼19 Mm, whereas the loops reconstructed using chromospheric extrapolations reach around ∼8.4 Mm above the solar surface with a foot-point separation of ∼16 Mm at the chromospheric height. The magnetic topology in the FER suggests the presence of small-scale loops beneath the large loops. Under suitable conditions, due to magnetic reconnection, these loops can trigger various heating events in the vicinity of the FER. Title: Chromospheric observations and magnetic configuration of a supergranular structure Authors: Robustini, Carolina; Esteban Pozuelo, Sara; Leenaarts, Jorrit; de la Cruz Rodríguez, Jaime Bibcode: 2019A&A...621A...1R Altcode: 2018A&A...621A...1R; 2018arXiv181010762R Context. Unipolar magnetic regions are often associated with supergranular cells. The chromosphere above these regions is regulated by the magnetic field, but the field structure is poorly known. In unipolar regions, the fibrillar arrangement does not always coincide with magnetic field lines, and polarimetric observations are needed to establish the chromospheric magnetic topology.
Aims: In an active region close to the limb, we observed a unipolar annular network of supergranular size. This supergranular structure harbours a radial distribution of the fibrils converging towards its centre. We aim to improve the description of this structure by determining the magnetic field configuration and the line-of-sight velocity distribution in both the photosphere and the chromosphere.
Methods: We observed the supergranular structure at different heights by taking data in the Fe I 6301-6302 Å, Hα, Ca II 8542 Å, and the Ca II H&K spectral lines with the CRisp Imaging SpectroPolarimeter (CRISP) and CHROMospheric Imaging Spectrometer (CHROMIS) at the Swedish 1-m Solar Telescope. We performed Milne-Eddington inversions of the spectropolarimetric data of Fe I 6301-6302 Å and applied the weak field approximation to Ca II 8542 Å data to retrieve the magnetic field in the photosphere and chromosphere. We used photospheric magnetograms of CRISP, Hinode Solar Optical Telescope spectropolarimeter, and Helioseismic and Magnetic Imager to calculate the magnetic flux. We investigated the velocity distribution using the line-of-sight velocities computed from the Milne-Eddington inversion and from the Doppler shift of the K3 feature in the Ca II K spectral line. To describe the typical spectral profiles characterising the chromosphere above the inner region of the supergranular structure, we performed a K-mean clustering of the spectra in Ca II K.
Results: The photospheric magnetic flux shows that the supergranular boundary has an excess of positive polarity and the whole structure is not balanced. The magnetic field vector at chromospheric heights, retrieved by the weak field approximation, indicates that the field lines within the supergranular cell tend to point inwards, and might form a canopy above the unipolar region. In the centre of the supergranular cell hosting the unipolar region, we observe a persistent chromospheric brightening coinciding with a strong gradient in the line-of-sight velocity.

The movie associated to Fig. 2 is available at https://www.aanda.org Title: The dynamic chromosphere: Results and techniques with an observational approach Authors: Robustini, Carolina Bibcode: 2018PhDT........98R Altcode: No abstract at ADS Title: The chromosphere above a δ-sunspot in the presence of fan-shaped jets Authors: Robustini, Carolina; Leenaarts, Jorrit; de la Cruz Rodríguez, Jaime Bibcode: 2018A&A...609A..14R Altcode: 2017A&A...609A..14R; 2017arXiv170903864R Context. Delta-sunspots are known to be favourable locations for fast and energetic events like flares and coronal mass ejections. The photosphere of this sunspot type has been thoroughly investigated in the past three decades. The atmospheric conditions in the chromosphere are not as well known, however.
Aims: This study is focused on the chromosphere of a δ-sunspot that harbours a series of fan-shaped jets in its penumbra. The aim of this study is to establish the magnetic field topology and the temperature distribution in the presence of jets in the photosphere and the chromosphere.
Methods: We use data from the Swedish 1m Solar Telescope (SST) and the Solar Dynamics Observatory. We invert the spectropolarimetric Fe I 6302 Å and Ca II 8542 Å data from the SST using the non-LTE inversion code NICOLE to estimate the magnetic field configuration, temperature, and velocity structure in the chromosphere.
Results: A loop-like magnetic structure is observed to emerge in the penumbra of the sunspot. The jets are launched from this structure. Magnetic reconnection between this emerging field and the pre-existing vertical field is suggested by hot plasma patches on the interface between the two fields. The height at which the reconnection takes place is located between log τ500 = -2 and log τ500 = -3. The magnetic field vector and the atmospheric temperature maps show a stationary configuration during the whole observation.

Movies associated to Figs. 3-5 are available at http://www.aanda.org Title: Fan-shaped jets above the light bridge of a sunspot driven by reconnection Authors: Robustini, Carolina; Leenaarts, Jorrit; de la Cruz Rodriguez, Jaime; Rouppe van der Voort, Luc Bibcode: 2016A&A...590A..57R Altcode: 2015arXiv150807927R We report on a fan-shaped set of high-speed jets above a strongly magnetized light bridge (LB) of a sunspot observed in the Hα line. We study the origin, dynamics, and thermal properties of the jets using high-resolution imaging spectroscopy in Hα from the Swedish 1m Solar Telescope and data from the Solar Dynamics Observatory and Hinode. The Hα jets have lengths of 7-38 Mm, are impulsively accelerated to a speed of ~100 km s-1 close to photospheric footpoints in the LB, and exhibit a constant deceleration consistent with solar effective gravity. They are predominantly launched from one edge of the light bridge, and their footpoints appear bright in the Hα wings. Atmospheric Imaging Assembly data indicates elongated brightenings that are nearly co-spatial with the Hα jets. We interpret them as jets of transition region temperatures. The magnetic field in the light bridge has a strength of 0.8-2 kG and it is nearly horizontal. All jet properties are consistent with magnetic reconnection as the driver.

Movies associated to Figs. 1 and 2 are available in electronic form at http://www.aanda.org