Aug  7 2010 but commented out before 
===========
DOT observing time is scheduled on the basis of scientific merit,
within the limitations set by DOT funding and staffing.~ Preference
is given to programs co-pointing the DOT with solar space
missions.~ Co-registration is feasible through overlapping Ca~II~HK
and/or continuum imaging (ultraviolet and/or white light,
respectively, for TRACE).~ The DOT scheduling is done in
consultation with the SST scheduler.~ Co-scheduling with other
groundbased telescopes than the SST must reckon with much smaller
probability of good-seeing coincidence.~ However, since good seeing
occurs fairly frequently even late in the day at La Palma,
overlapping and concatenate long-duration observing with US
telescopes is sometimes viable (local Sac Peak time is 5.9 hour
later, Big Bear 6.7 hour).

In external-user mode the external observer(s) must come to La Palma.
The easiest way is to
\htmladdnormallink{rent a car}
           {http://online.cicar.com/outset/cicar.htm}
and to   
\htmladdnormallink{stay at the Residencia}
                 {http://www.iac.es}.
See also the 
\htmladdnormallink{hints for students}
    {rrweb/rjr-edu/manuals/life-at-the-RdlM-brief-manual.txt}.
no blank

Jul 31 2010 
===========
\item March 2004: the 
  \htmladdnormallink{DOT speckle processor}{rrweb/dot-documents/dsp-2004.pdf}
  was displayed by
  \htmladdnormallink{Icebear Systems}
      {http://www.icebear-systems.de}
  at the 
  \htmladdnormallink{CeBIT fair}
      {http://www.cebit.de}.~  It has 70 Xeon CPUs in two compact racks
  with water cooling of all processors and controllers and heat storage
  for release at sunset.~  Photographs:
  \htmladdnormallink{both racks} 
      {dotshots/dsp-icebear.jpg},   
  \htmladdnormallink{one rack}
      {dotshots/dsp-one-rack.jpg}, 
  \htmladdnormallink{cooled processor}
      {dotshots/dsp-cooled-cpu.jpg}, 
  \htmladdnormallink{water connectors}
      {dotshots/dsp-water-connectors.jpg}, 
  \htmladdnormallink{open connector}
      {dotshots/dsp-open-connector.jpg}.

\item February 2004: official endorsement of the 
  \htmladdnormallink{collaboration in solar physics}
  {rrweb/dot-documents/uso-sp.pdf} between Utrecht, Stockholm, and Oslo.

\item Autumn 2007: the \htmladdnormallink{ENO/CCI report over
  2006} {rrweb/dot-documents/Annual-CCI-2006.pdf} sports a DOT cover.

\item February 2005: \htmladdnormallink{Dutch Technology Foundation STW}
         {http://www.stw.nl} has awarded the 
      \htmladdnormallink{DOT engineers}
       {dotshots/2004/hammerschlag+bettonvil.jpg} a grant of
      about 750~kEuro for perfection of the
      \htmladdnormallink{foldable dome} {dotshots/tent-delft.jpg}
      technology which they invented for the DOT and copied for
      GREGOR.

\item January 2008: \htmladdnormallink{index album to
 all DOT movies}{albums/movies/album.html} supplying them both as
 .avi and as .mov at slow frame rate to enable proper playing even
 with QuickTime.

< and more items from ``What's new'' not copied into here >

\item July 2005: welcome - Christoph Keller as full professor,
   Rony Keppens as affiliated professor, J\'ulius Koza as postdoc, Frans
   Snik as graduate student.
 
\item April 2005: DOT student Frans Snik graduated at Eindhoven University 
  on the 
 \htmladdnormallink{design for imaging polarimetry with the
    DOT}{rrweb/dot-documents/snik-report-2005.pdf}.



Jul 22 2010  a whole lot out but copied into my own ``What's past''
============================

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{DOT research:~ science context,~ status,~ projects}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT science context}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

The paradigm of stellar activity says that stellar coronae and
chromospheres are heated magnetically, but it remains an open question
how this comes about. Since the fields are anchored in the dense gas
at the solar surface, the dynamics of flux tubes, pores and spots lie
at the root of outer-atmosphere heating.  By combining high-resolution
surface imaging and magnetometry with ultraviolet spectrometry and
coronal imaging from space, one may correlate and trace surface
topology and motions and the corresponding chromospheric topology and
dynamics in magnetic structures tomographically, all the way out into
the optically-thin plasma regime.

\par
Other DOT science goals consist of studying the
emergence and decay patterns of solar magnetic fields, the 
photospheric-chromospheric dynamic connection in non-magnetic 
regions, the fine structure of plage and sunspots, and
the fine structure of prominences.

\par
More detail is given below, especially for tomographic "proxy
magnetometry" which constitutes the principal DOT science strength.
%% no blank line here
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsubsection{Solar magnetism}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Magnetism lies at the root of most solar and heliospheric physics.
The intricate structure of the solar field, the activity cycle and the
influence of the field on the heliosphere represent major quests of
(astro-)physics which bear directly on the human environment.  The
sun's magnetic field is generated by enigmatic dynamo processes in the
solar interior, is organised into the highly complex patterns of solar
activity observed in the solar photosphere, dominates the structure of
the outer solar atmosphere (chromosphere, transition region, corona),
regulates the solar wind, and affects the whole extended heliosphere.

\par
In terms of pure science, solar magnetism provides the Rosetta stone
of cosmic magnetism, not only in other stars but also in accretion
disks, cataclysmic variables, galactic dynamics, active galactic
nuclei and other cosmic objects in which MHD and plasma processes
control the structure and energy partitioning.  The sun is close
enough to study these processes in observable detail.

\par
Terrestrial plasma confinement machines do not reach the scales,
densities and temperatures exhibited in the solar atmosphere.  Solar
physics complements plasma instability studies in fusion research, the
sun representing a non-terrestrial plasma physics laboratory.

\par
Space weather (the solar influence on the near-earth environment and
the Earth's climate) is set by solar magnetism.  Solar activity
modulation affects satellite orbits, influences jet stream patterns
and contributes to the causes of minor, possibly major, ice ages.

\par
Solar surface magnetism is the key for advance in these research
areas. At the surface, the magnetic field wins from the gas pressure:
the plasma beta parameter (ratio of gas to magnetic pressure) flips
from large to small across unity, so that the field role switches from
being dominated by gas motions to dominating gas motions.  At the
solar surface, the field displays patterning imposed by the subsurface
dynamo and convective flows while, at the same time, it controls flows
and wave motions to the outer atmosphere.  This flip in domination
makes it desirable to observe the magnetic field patterning
simultaneously in the photosphere and the overlying chromosphere.  The
DOT is specifically suited to such solar surface magnetometry with
high spatial (angular) resolution.

\par
The solar atmosphere changes dramatically between different regimes
and presents drastically different scenes to the terrestrial observer
at different wavelengths.  The solar photosphere, defined as the layer
where the bulk of the electromagnetic radiation escapes as visible
light (a dramatic transition from near-equilibrium photon enclosure,
killing off the subsurface convection into the shallow pancake pattern
called granulation) is also the layer where magnetic fields take over
from gas dynamics in dictating the structuring and in supplying the
key processes, and it is also the outermost layer where the sun may be
regarded as spherical in zero-order approximation.  The chromosphere
is magnetically split into network and internetwork in quiet regions
and is very finely structured above active regions.  The transition to
the corona consists of tiny fibrils with much variation in length,
inclination, and ordering.  The closed-field parts of the corona
outside coronal holes are made up of bundles of very thin coronal
loops.  Yet unidentified processes supply energy to the gas in these
loops, reaching a balance against cooling by X-ray photon losses at
temperatures of 1--2~million~K.

The loops are magnetically anchored (in unknown fashion) to the
strong-field flux tubes that break out of the photosphere and respond
dynamically on a wide variety of timescales to the footpoint forcing.
These magnetic connections between very disparate regimes, from gas
dynamics via magnetohydrodynamics to plasma physics and from LTE
radiation enclosure to X-ray photon drain, require simultaneous study
of structures, processes and radiation in the photosphere,
chromosphere, transition region and corona.  This calls for
tomographic diagnostics sampling the different regimes at the same
time.

\par
{\em Reference: "Solar Surface Magnetism", 
     Edited by R.J. Rutten and C.J. Schrijver, 
     NATO ASI Series C433, Kluwer, Dordrecht}

\subsubsection{High-resolution proxy magnetometry}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
With its speckle data-acquisition system, the DOT became the first
solar telescope to regularly provide long-duration (multiple hours)
image sequences at consistent 0.2~arcsec resolution over a sizable
field (90~x~70~arcsec).  The
\htmladdnormallink{DOT speckle processor}{rrweb/dot-documents/dsp-2004.pdf} 
enables storage and fast speckle processing for daily observing runs
of up to 8 hours duration using all DOT cameras at 15-20~s speckle
burst cadence.  With its multi-wavelength speckle system the DOT also
became an unparallelled mapper of the magnetic topology and its
dynamics in tomographic fashion, simultaneously for the photosphere (G
band), low chromosphere (Ca~II~H), and high chromosphere (tuned
Halpha), and of the radial photospheric Doppler velocity (Ba~II~4554).

This long-duration high-resolution multi-wavelength imaging capability
presents a unique opportunity within solar physics to study the
horizontal topology and vertical structure of solar magnetic fields.
Such tomographic high-resolution imaging is also desirable as
context information to high-resolution spectropolarimetry at other
telescopes employing adaptive optics, and to coronal field mapping
using ultraviolet and X-ray image sequences from space. This section
discusses DOT tomographic imaging in terms of its "proxy
magnetometry" information content in some depth.


\par
Solar surface magnetism consists of a remarkable hierarchy of
discrete strong-field structures.  
The basic entity is the {\em flux tube}, a key concept of MHD astrophysics.
Solar flux tubes have tiny cross-sections (0.2 arcsec) 
but they have nevertheless become observable with Canary-Island 
seeing quality, particularly in the  
      \htmladdnormallink{Fraunhofer G-band}{dotshots/gband.jpg}
around 4305~\AA.
At this wavelength, the flux tubes show up as tiny
bright points as in the magnified inset in this
      \htmladdnormallink{DOT image}{images/annotated-pit.jpg}.
At high angular resolution, G-band imaging provides 
a useful proxy diagnostic for charting
photospheric flux tube patterns and their development
(see
    \htmladdnormallink{Title \& Berger 2001}
{http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001ApJ...553..449B&db_key=AST&high=3b8cc0023025178}).

\par
The brightness of the intergranular magnetic elements is explained by 
the "flux tube hot wall" effect  
    \htmladdnormallink{(e.g.~Spruit \& Zwaan 1981)}
{http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1981SoPh...70..207S&db_key=AST&high=3b8cc0023028048}:
the tube is relatively empty because the inside magnetic pressure
balances the outside gas pressure, and so it acts as a viewing tube
through which radiation escapes from layers below the outside
surface, with the hot tube walls producing brighter emission than the
surroundings. In the 
  \htmladdnormallink{G band}{dotshots/gband.jpg},
around 4305~\AA\ (430.5 nm, labeled G by 
  \htmladdnormallink{Joseph von Fraunhofer}
    {http://www.newadvent.org/cathen/06250a.htm}
in his 1814 inventory of the solar spectrum)
this contrast is enhanced because the CH 
molecules which make up most lines in this 
dark feature dissociate in the flux tube, so that the CH
lines vanish and the tube gas gains even more transparency
compared to the outside gas than at other wavelengths
(see  
  \htmladdnormallink{Rutten et al.~2001}
    {rrweb/rjr-pubs/2001sunspot-gband.pdf}).

\par
The intrinsic sharpness of the photospheric flux tubes is very high
because they are very thin and the G-band photons are emitted
thermally and are not much spread by scattering on their way out.  At
100~km resolution most resulting G-band bright points are not
resolved, but at least they are identifiable so that they can be
located and traced in time.  At somewhat lower resolution (say
0.5~arcsec) they vanish (because they are mostly located within dark
intergranular lanes so that smearing by atmospheric seeing cancels
bright against dark,
   \htmladdnormallink{see Title \& Berger 1996}
    {http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1996ApJ...463..797T&db_key=AST&high=3b8cc0023028228}).

\par
Higher up in the chromosphere, the    
  \htmlimagelink{Ca~II~H \& K lines}
    {dotshots/cahk-neckel}
    {jpg}{pdf}{10cm}{0}
of once-ionised calcium and the
  \htmlimagelink{Balmer Halpha line}
    {dotshots/halpha-neckel}
    {jpg}{pdf}{10cm}{0}
also provide valuable proxies for mapping magnetic topology.
The low chromosphere sampled by Ca~II~H or K shows clusters of bright
grains outlining the magnetic network and greyish internetwork
features marking acoustic oscillation interference patterns.  The high
chromosphere sampled by Halpha portrays the intricate structure of the
magnetic canopies expanding from the network in the form of fine
fibrils.

\par
The Ca~II~H \& K lines are the strongest Fraunhofer lines and sample
the chromosphere at about 1000~km above the white-light surface.
At this height, the magnetic network is enhanced by yet
unidentified heating processes so that the Ca~II line-center intensity
(at about 0.1~nm bandwidth) provides an excellent magnetogram proxy
(but unsigned). This fact has been exploited extensively in
gauging the magnetic activity of sun-like stars. 

\par
The sharpness of Ca~II~H or K images is intrinsically less than for the G
band, partially because the line photons are scattered considerably on
their way out before their final escape towards the observer, and
partially because the flux tubes expand and merge with height.  The
same regime and the same patterning are also sampled by imaging in the
near-UV continua, but these scatter as badly.

\par
The Balmer Halpha line comes from the most abundant element but is
much less strong than Ca~II~H \& K in the spatially averaged solar
spectrum because its lower-level population has very low weight in the
Boltzmann population partitioning over the hydrogen energy levels.
Nevertheless, its high excitation energy causes this line to respond
to gas at high temperature and also to shocked cool gas, so that it
maps low-lying fibrils in the high chromosphere when these are
sufficiently dense.  This regime has often been modeled as a spherical
shell, but a high-resolution Halpha movie immediately shows the
fallacy of such modeling by displaying a mass of fibrils with no
semblance of sphericity whatsoever.  The "moss" phenomenon discovered
with TRACE indicates that 2~million-K plasma actually descends down to
between the Halpha fibrils in plage \htmladdnormallink{(see Berger et
al.~1999)} {http://esoads.eso.org/abs/1999ApJ...519L..97B}.

\par
It is becoming increasingly clear that the chromospheric fibril
topology mapped by Halpha supplies a missing link between photospheric
magnetograms (such as from MDI onboard SOHO and from HMI onboard SDO)
and the coronal field topology.  Nonlinear force-free-field
extrapolation from such magnetograms is much better determined and
much more realistic when Halpha fibril topology is entered as a
constraint in the extrapolation procedure
\htmladdnormallink{(see Bobra et al.~2008)}
{http://esoads.eso.org/abs/2008ApJ...672.1209B}.  It is probable
that such Halpha insertion in field topology estimation will be
decisive in setting up reliable techniques for forecasting solar
eruptions and near-earth space weather.

\par
Using Halpha as magnetograph proxy to derive the field topology from
the observed fibrils is not straightforward because the latter harbor
length-wise flows that modulate the apparent fibril contrast through
substantial Dopplershifts.  The resulting mix of brightness and
Dopplershift variations requires full profile modeling, so that
filtergrams must be taken at a number of wavelengths and interpreted
through inversions based on sophisticated radiative transfer modeling.

\par
The intrinsic Halpha resolution can be exceedingly high because the
fibrils may be effectively or even optically thin, imposing their
scale on the emergent radiation without radiative-transfer smearing.
This is particularly the case in filaments and prominences (the latter
are filaments seen off-limb where the background radiation along the
line of sight vanishes).  These amazing structures, keeping very cool
gas up amidst the hot corona and persisting very long, are rich
sources of MHD physics.  They probably consist of very thin, highly
dynamic magnetic fibrils in complex topologies that are best encoded
in Halpha radiation.

\par
The DOT is operated from the SST building
\htmladdnormallink{in close cooperation}
                  {rrweb/dot-documents/uso-sp.pdf} with the Swedish
collagues.  The 
Swedish 1-m Solar Telescope (SST)
achieves high-resolution
imaging, spectrometry and polarimetry using adaptive optics.  The two
telescopes are complementary.  Together, they represent a formidable
facility for high-resolution solar physics.

\par 
Specific DOT research topics:
\begin{itemize}

 \item solar wave dynamics: network and internetwork oscillations,
    gravity waves, umbral flashes, wave excitation;

 \item solar surface fields: fluxtube patterns, fluxtube dynamics,
    magnetic carpet topology and evolution, sunspot structure and
    dynamics, prominence stability and eruptions;

 \item topology and evolution of active regions: plage emergence and
    disappearance, eruption precursor topology, sunspot breakup;

 \item canopy transitions: wave penetration and heating, moss
 structure and dynamics, fibril topology, evolution and dynamics,
 spicule physics, tube-loop coupling.

\end{itemize}


\subsubsection{High-resolution Doppler mapping}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Charting dynamical flows along magnetic structures requires the
measurement of spectral-line Doppler displacements in two-dimensional
image format rather than the linear cutout selected by spectrograph
slits.  High-resolution Doppler mapping therefore calls for tunable
narrow-band filtergraphs.

Here is
    \htmlimagelink{a high-resolution Dopplergram}
    {images/dopplergram}
    {gif}{pdf}{16cm}{0} 
which resulted from a test of a
   \htmladdnormallink{of a special tunable filter from Irkutsk}
    {rrweb/dot-documents/irkutsk.pdf}.
The test was done at the former SVST and is  
\htmladdnormallink{described here in detail}
  {rrweb/rjr-pubs/2001AAp...378..251S.pdf}.
This filter selects a tunable narrow band in the
\htmlimagelink{Ba~II~4554 line}
    {dotshots/baii-neckel}
    {jpg}{pdf}{10cm}{0}
which possesses enhanced sensitivity to non-thermal motions due to the
large atomic mass of barium atoms.  

The test showed that a new domain of flow mapping opens up at the high
resolution obtainable with this line, speckle restoration and La Palma
image quality.  At this unprecedented Dopplergram resolution, it
becomes possible to chart flows in and around small basic structures
such as the magnetic elements that make up the chromospheric network,
in and between the fibrils making up penumbrae, and along the thin
threads constituting filaments and prominences.

We have, thanks to support from
\htmladdnormallink{INTAS}{http://www.intas.be} and the Pieter
Langerhuizen Lambertuszoon Fonds, installed the Irkutsk filter on the
DOT.  It was then found that it needed complete overhaul, for which
R.H. Hammersclag and F.C.M. Bettonvil took it to Irkutsk in 2008.  It
operates on the DOT since June 2009, but the poor camera used (for
lack of funding) limits the signal-to-noise ratio severely.


\subsubsection{High-resolution Stokes magnetometry}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The next step in DOT postfocus instrumentation is to proceed from
proxy magnetometry to quantitative measurement of the magnetic field,
preferably in the form of full Stokes-vector magnetometry.  The science
prospects of a high-resolution Stokes-vector magnetograph are obvious.
Since solar magnetic fields are the key to understanding the
structures and dynamics of the solar atmosphere, precise vector
magnetometry is a desirable ingredient to almost every observing program.

\par
The DOT is particularly suited for such magnetometry.  First, it
provides the required angular resolution.  Second, because it is a
reflector the focus is co-spatial at all wavelengths.  Third, the
parallactic mount and the absence of image rotation make it suited to
high-precision polarimetry.  Fourth, its high pointing precision
permits astrometric tracking in solar coordinates.  Finally, the
projected aperture increase will give it the high sensitivity needed
for precision polarimetry.

We had hoped to turn the 
\htmladdnormallink{Irkutsk Ba~II~4554 filter}
              {rrweb/rjr-pubs/2001AAp...378..251S.pdf} into a Stokes
vector magnetograph by adding liquid-crystal retarders, but the present
camera is too noisy to make this a realistic extension.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT status}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The science prospects of the DOT are excellent, but its long-term
future is much less rosy with respect to funding.  Utrecht University
and NOVA terminated their support for DOT operation per 1--1--2008.
Thus, the DOT is in dire need of external sponsoring.  If you happen
to seek a worthy goal for giving a gift, for an endowment, for
sponsoring science through a donation, then please consider the human
endeavour of understanding (and living with) our own star and
contribute to the foundation SOZOU (\htmladdnormallink{secretary
Dr. H. Uitenbroek}{http://www.nso.edu/staff/uitenbr}
 {\it -- met een gift, schenking, legaat,
hulp in sponsorwerving doet U de DOT voortbestaan.}

\par
Our DOT development plan, obviousy depending on renewed sponsoring, is
to install remote targeting, a database search facility, integration
into the worldwide Virtual Solar Observatory, aperture tripling
(resolution down to 0.07 arcsec), field tripling (up to 300 arcsec),
or yet larger upgrades.  More detail is given
\htmladdnormallink{on the next page}{DOT_projects.html}.




%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT projects}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

The DOT team is very small but there is no shortage of ideas to
exploit and enhance the unique DOT capacity for high-resolution solar
physics.  Unfortunately, the speed of realisaton is limited by funding
and manpower - the DOT funding is much lower than for comparable solar
telescope projects elsewhere, and much much lower than for comparable
solar telescopes in space.

\par
The following projects constitute our DOT to-do list, roughly in time
order.  The first two are done with respect to the DOT but have new
life with respect to future telescope projects such as the EST.
Currently the DOT operation represents projects 3 through 5.  Project
6 materialized with the installation of the Irkutsk Lyot filter for
Ba~II~4554 in June 2006 but its camera is too nosiy for projects 7.
We have no manpiower for project 8.  Projects 9 to 11 remain dreams
awaiting sponsoring.


{\em (1) Verification of DOT technology} \\
The initial DOT post-focus
equipment was limited to the verification imaging 
needed to prove that the DOT fulfills its design criteria.  The
completion and the installation of the DOT were funded by the
\htmladdnormallink{Dutch Technology Foundation STW}
         {http://www.stw.nl}
on the basis of the technological
innovations that make the DOT a stable pointer even while exposed to
strongly varying wind loads.  This new (mostly mechanical) 
technology has indeed been demonstrated to work.  There are no
windshake problems, and the telescope, tower and clamshell canopy have
survived multiple fierce La Palma winters without problem.

\par
{\em (2) Verification of the open principle} \\
From the solar physicist
point of view, DOT verification consists of testing its open
principle.  The DOT is the first solar telescope that relies on the
ambient wind (often very strong at La Palma) to inhibit image-spoiling
turbulence within the telescope.  The DOT's demonstration
that this strategy of wind flushing works has been a pivotal factor
in the current wave of large open-telescope projects, in particular
  \htmladdnormallink{GREGOR}
  {http://gregor.kis.uni-freiburg.de},
\htmladdnormallink{NST}
  {http://www.bbso.njit.edu/newtelescope}
and
  \htmladdnormallink{ATST}
           {http://atst.nso.edu},
and also inspires the 
  \htmladdnormallink{GISOT concept}
  {rrweb/dot-publications/gisot2004.pdf}.

\par
{\em (3) Proxy magnetometry} \\ The initial observing program
consisted of proxy magnetometry as described above, using imaging in
the G-band to chart magnetic field structures and patterns and their
evolution in the photosphere.  We added imaging in Ca~II~H to do the
same for the low chromosphere, and narrow-band imaging in Halpha to do
the same for the upper chromosphere.  The bandwidths are 1~nm for the
G-band, 0.3~nm for Ca~II~H and 0.025~nm for Halpha.  The first two
permit the use of simple interference filters but the Halpha passband
must not only be narrow but also rapidly tunable.  The DOT team has a
high-quality Halpha Lyot filter that was earlier employed at the
Ottawa River Solar Observatory.  It is mounted adjacent to the
incoming beam (see \htmladdnormallink{DOT top design drawing}
{dotshots/HoekpuntD1B.jpg}) and
\htmladdnormallink{secondary optics design drawing}
{dotshots/felix-multiwav.jpg}.  This program aims in particular at
obtaining high-resolution image sequences in conjunction with the MDI
magnetograph and UV spectrometers onboard the \htmladdnormallink{SOHO
mission} {http://sohowww.nascom.nasa.gov/}, the
high-resolution UV imaging by the
\htmladdnormallink{TRACE mission}
           {http://vestige.lmsal.com/TRACE/},
the photospheric diagnostics of the 
\htmladdnormallink{Hinode mission}{http://hinode.nao.ac.jp/index_e.shtml},
and the upcoming large-volume solar monitoring of the
SDO mission.
%?? website?

\par
{\em (4) Image restoration} \\
High angular resolution is the science driver 
for the DOT - as for most other solar telescopes excepting
helioseismology.
Thanks to the combination of the wind-swept site,
the wind-flushed open tower and telescope, and the consistent
application of speckle restoration, 
the DOT furnishes diffraction-limited image quality
whenever the seeing is only reasonably good, 
i.e. with Fried parameter (effective resolution permitted by
the Earth's atmosphere expressed in corresponding telescope
diameter) of order 6-10~cm.
A major advantage of speckle processing 
over the adaptive-optics systems being
developed for future solar telescopes is that speckle reconstruction
restores the full field of observation, not just a single
isoplanatic patch.  The major disadvantage is that it takes a large amount
of post-processing.   This is remedied with the
\htmladdnormallink{DOT speckle processor}{rrweb/dot-documents/dsp-2004.pdf}.

\par
{\em (5) Common-user operation} \\ In 2004 we opened the DOT as
common-user facility to the international solar physics community.
Many solar observing programs at other telescopes (both groundbased
and in space) can then benefit from high-resolution context imaging
with the DOT.  
Details:
\htmladdnormallink{White paper on future DOT observing modes}
{rrweb/dot-documents/dot-vso.pdf}.

\par
{\em (6) Doppler mapping} \\
A test done at the SVST in its last season (summer 2000) demonstrated
the tantalizing science capability of the special
tunable Lyot filter operating in the Ba~II~4554
that 
  \htmladdnormallink{was developed at Irkutsk}
           {rrweb/dot-documents/irkutsk.pdf}
by V.I. Skomorovsky and G.N. Domishev.
  \htmladdnormallink{They brought it to the SVST}
       {dotshots/Russen1.jpg}
where it was combined with the
DOT speckle acquisition system, on funding from SOZOU, LKBF and NOVA.
The superb angular resolution obtained by the speckle processing
and the large sensitivity of the 
Ba~II~4554 line to motions
(due to the combination of very large atomic mass and insensivity 
 of the line opacity to temperature variations) combine to 
 \htmladdnormallink{Dopplergrams of extraordinary information content}
    {images/dopplergram.gif}
as detailed 
  \htmladdnormallink{here}
                    {rrweb/rjr-pubs/2001AAp...378..251S.pdf}.
An accommodation study has shown that the DOT can harbour this
  \htmladdnormallink{large and heavy Lyot filter}
  {dotshots/bariumsetup1.jpg}
with telecentric re-imaging optics within the
telescope top
  (\htmladdnormallink{design drawing}
           {dotshots/aswin-multiwav.jpg}).
Funding to realize its installation was
been obtained from INTAS, the Pieter Langerhuizen
Lambertuszoon Fonds, and SOZOU, but then it was found that the
filter needed extensive refurbishment, for which R.H. Hammerschlag and
F.C.M. Bettonvil took it back to Irkutsk in 2008.  It operates
on the DOT since June 2009 but the camera is too noisty to 
contemplate extension into a magetograph.

\par
{\em (7) Stokes magnetometry} \\
The development and installation of a Stokes
vector magnetograph is a natural desire.  Stokes vector magnetometry
requires spectral selection of one or more narrow bandpasses within
one or more Zeeman-sensitive lines.  Our intention was 
to outfit the
\htmladdnormallink{Irkutsk Ba~II~4554 birefringent filter}
{rrweb/rjr-pubs/2001AAp...378..251S.pdf} with ferro-electric liquid
crystal retarders but the present camera is too bad.  Another
option for a compact instrument fitting the cramped DOT top is to use
a multiple Fabry-Perot interferometer.
%%Another compact option is the use of magneto-optic resonance
%%cells.
%% being pursued in
%% \htmladdnormallink{ESMN context}
%%        {http://www.phys.uu.nl/~rutten/esmn}
%%by colleagues at the 
%%  \htmladdnormallink{OAC in Naples}
%%  {http://arthemis.na.astro.it/VAMOS/}.
A larger-scale option is the use of optical fibers to transfer the
image to a classical grating spectrometer for two-dimensional
small-field spectrometry by using a \htmladdnormallink{fiber
  field-to-slit reformatter}
{rrweb/rjr-pubs/1999sunspot-fiber.pdf} combined with
phase-diverse data acquisition.

\par
{\em (8) Remote targeting}\\ Many international multi-telescope
campaigns address phenomena related to solar activity and therefore
require selection of the common field of view on short to very short
notice (the latter for example when observing flares or filament
eruptions).  Co-pointing diverse instruments at different telescopes
is therefore greatly assisted by facilities for (nearly) instantaneous
remote targeting.  At the DOT, such a remote pointing interface can be
a low-bandwidth emulation of the actual telescope control interface in
the 
 \htmlimagelink{DOT control room}{dotshots/DCP-5006}
    {jpg}{pdf}{10cm}{0}
(already remote itself).  It will also enable 
staff at Utrecht (or elsewhere) 
to look over the shoulder of observers on La Palma.
Details are also given in  
  \htmladdnormallink{the white paper on future DOT observing modes}
           {rrweb/dot-documents/dot-vso.pdf}.

\par (9)
{\em Triple aperture increase} \\ The mechanical structure of the DOT accepts
a larger mirror than the current 45~cm one, at least 140~cm without
replacing the telescope mount nor the multi-wavelength secondary
optics and camera system.  A detailed design has been made to
verify the opto-mechanical feasibility 
\htmlimagelink{(optics diagram)}
              {dotshots/140cmAO4}{jpg}{pdf}{14cm}{90}.  
A new light-weight parabolic primary mirror of 140~cm diameter will
feed the existing multi-wavelength recording system via new beam
folding and reformatting optics.  A super-reflective, water-cooled
field stop with air suction around it in prime focus reflects most of
the solar image and passes the field of view to the relay mirrors, of
which the first one is parabolic and cancels the coma of the parabolic
primary, producing a large field of view.  A telecentric region can
harbour polarisation encoders for 
%% Ba II 455.4~nm 
magnetometry.  A choice of beam reformatting lens combinations and a
fixed pupil stop permits flexible user-selectable trade-off between
resolution and field size, producing a 1:45 beam into the
multi-wavelength system just as in the present 45-cm DOT.  The
projection will be via a low-order adaptive optics system which serves
to increase the signal-to--noise ratio of the speckle processing.  The
G-band channel will no longer be on-axis so that the central
obscuration will be small.  The beam reformatter permits flexibility
in usage.  At superb seeing, when speckle restoration will work down
to the 0.07~arcsec diffraction limit of the 140-cm aperture, the
aperture tripling will fully regain the DOT's role of tomographic
imager even in the Hinode era --- and actually enhance Hinode through
co-observing: the DOT can then image at 0.07~arcsec (50~km on the
solar surface, equal to the photon mean free path in the photosphere)
what Hinode diagnoses at 0.2~arcsec.  When the seeing is less good one
opts for lower resolution but a concomitantly larger field of view on
the camera chips.  A pupil shifter then permits selection of an
obscuration-free off-axis aperture.

{\par (10)
\em Triple field increase}\\
The introduction of a parabolic secondary mirror will cancel coma from
the parabolic primary which presently limits the useful DOT field of
view to three arcmin.  Since much larger CCD chips with the
10~frames/s readout speed needed for speckle burst registration should
become affordable with time, we intend later in this decade to revamp
the DOT cameras and speckle pipeline with state-of-the-art hardware
and so increase the field of view considerably at any resolution.  For
example, during non-superb seeing 4K~x~4K chips would register 300 x
300~arcsec at 0.2~arcsec resolution and enable studies of the topology
and dynamics of whole active regions including complete coronal loop
anchoring.  When the seeing turns excellent - as flagged by our
reliable Seykora-Beckers scintillometer - shift to 0.07~arcsec
resolution then reduces the field to 100~x~100~arcsec, still large
enough to contain a complete mature sunspot with its moat.  Increasing
the disk storage (or accelerating the speckle processing to real-time
turnaround) will increase the maximum sequence duration.

{\par (11)
\em Upgrade options beyond tripling}\\
We have also made preliminary designs for yet larger-scale upgrades of the
telescope, the tower, and the platform.  See
\htmladdnormallink{Aperture Increase Options for the Dutch Open Telescope}
                  {rrweb/rjr-pubs/2007ASPC..368..573H.pdf}.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{DOT education:~ student program}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

The "Students-to-the-DOT" program brought pairs of students for two
weeks to La Palma to receive intensive on-the-spot tutoring in solar
physics, astronomical observing techniques, image processing, and data
interpretation.  Tutoring was by Prof. R.J. Rutten (solar physics),
Dr. P. S\"utterlin (solar physics and image processing), Ir. F.C.M
Bettonvil (observing techniques), Dr. R.J. Hammerschlag (telescope
design), and the assorted guest observers at the DOT and SST.

Each student was assigned a solar physics research topic including
analysis of recent data.  The project generally started with a week of
introductory solar physics study at the home institute, two weeks at
the Roque de los Muchachos Observatory, and either two weeks of
completion and report writing at the home institute for an allocation
of 7.5 ECTS, or seven weeks of further research for 15 ECTS.  Both
Bachelor's and Master's students were eligible.

Additional student activities on La Palma were the giving of
presentations in the Utrecht-Stockholm-Oslo Seminar Series, sharing in
DOT observing, orientation at the SST, and excursions to nighttime
telescopes at the Roque de los Muchachos Observatory including
Grantecan, the largest optical telescope worldwide.

The highly successful program operated during 2004--2007, bringing 28
students to La Palma.  It terminated when Utrecht University
terminated its DOT funding on January 1, 2008.

\htmladdnormallink{{\em DOT student list}}{web-students.txt}

DOT student manuals:
~~\htmladdnormallink{La Palma}
     {rrweb/rjr-edu/dot}
\gap\htmladdnormallink{LaTeX \& BibTeX}
     {rrweb/rjr-edu/latex}
\gap\htmladdnormallink{IDL}
     {rrweb/rjr-idl}
\gap\htmladdnormallink{Linux}
     {rrweb/rjr-edu/linux}
%% no blank here
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT students-2007 photos}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% hyphen above necessary for link split

Helena Becher, Vasco Henriques, Leandro Jesus, Nikola Vitas\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2007/071020-R0013921.jpg}\\
  \gap\htmladdnormallink{on the lookout}
       {studentshots/2007/071025-0135.jpg}\\
  \gap\htmladdnormallink{observing Venus}
       {studentshots/2007/071020-R0013911.jpg}\\
  \gap\htmladdnormallink{ready for the green flash}
       {studentshots/2007/071024-0007.jpg}\\
  \gap\htmladdnormallink{in the SST library}
       {studentshots/2007/071023-0134.jpg}\\
  \gap\htmladdnormallink{at the DOT}
       {studentshots/2007/071020-0030.jpg}\\
  \gap\htmladdnormallink{at the SST}
       {studentshots/2007/071020-0061.jpg}\\
  \gap\htmladdnormallink{at the INT}
       {studentshots/2007/071023-0147.jpg}\\
  \gap\htmladdnormallink{at Grantecan}
       {studentshots/2007/071024-0062.jpg}\\
  \gap\htmladdnormallink{at data acquisition}
       {studentshots/2007/071025-0074.jpg}\\
  \gap\htmladdnormallink{on the career ladder}
       {studentshots/2007/071025-R0014046.jpg}\\

Pedzi Girigori \& Reinier Zeldenrust\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2007/070922-R0013560.jpg}\\
  \gap\htmladdnormallink{at data evaluation}
       {studentshots/2007/070929-R0013679.jpg}\\
  \gap\htmladdnormallink{in the SST kitchen}
       {studentshots/2007/071001-R0013714.jpg}\\
  \gap\htmladdnormallink{in the SST library}
       {studentshots/2007/071005-R0013739.jpg}\\

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT students-2006 photos}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% hyphen above necessary for link split

Catherine Fischer, Judith Palacios, Juan Martinez Sykora (USO),
Arek Berlicki (ESMN) \& Prisca Zwaan (SOZOU)\\
  \gap\htmladdnormallink{in the DOT elevator with Rob Hammerschlag}
       {studentshots/2006/060923-p1030259C.jpg}\\
  \gap\htmladdnormallink{studying their cameras}
       {studentshots/2006/060923-p1030272C.jpg}\\
  \gap\htmladdnormallink{studying the DOT}
       {studentshots/2006/060923-p1030287C.jpg}\\
  \gap\htmladdnormallink{in the DOT control room with Pit S\"utterlin}
       {studentshots/2006/060923-p1030315C.jpg}\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2006/060923-p1030317C.jpg}\\
  \gap\htmladdnormallink{measuring Grantecan}
       {studentshots/2006/060923-p1030324C.jpg}\\
  \gap\htmladdnormallink{measuring mantis}
       {studentshots/2006/060928-p1030373C.jpg}\\

Luc Rouppe van der Voort \& Peter Jonker\\
  \gap\htmladdnormallink{a decade after their application}
       {studentshots/2006/060914-p1030177C.jpg}\\

Hesdy Hoekstra \& Marijke Huijgen-Holsappel\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2006/hesdy-marijke-rdlm.jpg}\\
  \gap\htmladdnormallink{in SST library}
       {studentshots/2006/hesdy-marijke-bib.jpg}\\
  \gap\htmladdnormallink{in the DOT, with Felix Bettonvil}
       {studentshots/2006/hesdy-marijke-dot2.jpg}\\
  \gap\htmladdnormallink{in the DOT, with Felix Bettonvil}
       {studentshots/2006/hesdy-marijke-dot.jpg}\\
  \gap\htmladdnormallink{contemplating calibration}
       {studentshots/2006/hesdy-marijke-fall.jpg}\\
  \gap\htmladdnormallink{contemplating calibration}
       {studentshots/2006/hesdy-marijke-fall2.jpg}\\

Gregal Vissers \\
  \gap\htmladdnormallink{with Alfred de Wijn on the Roque}
       {studentshots/2006/060709-p1020391C.jpg}\\
  \gap\htmladdnormallink{instructed by Alfred de Wijn}
       {studentshots/2006/060709-p1020396C.jpg}\\
  \gap\htmladdnormallink{instructed by the wrong R.~Rutten}
       {studentshots/2006/060709-p1020397C.jpg}\\

Jeroen Burgers \& Marcin Dukalski\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2006/dukalski+burgers-rdlm.jpg}\\
  \gap\htmladdnormallink{on the DOT, with Rob Hammerschlag}
       {studentshots/2006/dukalski+burgers-dot0.jpg}\\
  \gap\htmladdnormallink{on the DOT, with Rob Hammerschlag}
       {studentshots/2006/dukalski+burgers-dot2.jpg}\\
  \gap\htmladdnormallink{Jeroen at data sampling}
       {studentshots/2006/burgers-sampling.jpg}\\
  \gap\htmladdnormallink{Marcin at literature study}
       {studentshots/2006/dukalski-literature.jpg}\\

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT students-2005 photos}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Sebastiaan Keek \& Bob van Veelen\\
  \gap\htmladdnormallink{in SST library}
       {studentshots/2005/vanveelen+keek-bib.jpg}\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2005/vanveelen+keek-rdlm.jpg}\\
  \gap\htmladdnormallink{receiving DOT tutoring from Alfred de Wijn}
       {studentshots/2005/alfreddewijn-dot.jpg}\\

Ernst Kuiper \& Incognito\\
  \gap\htmladdnormallink{in SST library}
       {studentshots/2005/Incognito+Kuiper-bib.jpg}\\
  \gap\htmladdnormallink{on the Roque}
       {studentshots/2005/Kuiper+Incognito-RdlM.jpg}\\
  \gap\htmladdnormallink{in Jan Rybak's ESMN-USO seminar
         (taken by Ales Kucera)}
       {studentshots/2005/241831L.jpg}\\
  \gap\htmladdnormallink{on exploration}
       {studentshots/2005/Incognito+Kuiper-ladder.jpg}\\

Klaartje Schure \& Tim van Werkhoven\\
  \gap\htmladdnormallink{USO seminar announcement}
       {studentshots/2005/uso-sem-announce.jpg}\\
  \gap\htmladdnormallink{with Rob Rutten in SST library}
       {studentshots/2005/51005039S.jpg}\\
  \gap\htmladdnormallink{Klaartje with Rob Hammerschlag and
        Rob Rutten in SST kitchen, taken by Tim}
       {studentshots/2005/tim-6827.jpg}\\
  \gap\htmladdnormallink{with Rob Hammerschlag on the DOT}
       {studentshots/2005/51004010Sa.jpg}\\
  \gap\htmladdnormallink{admiring the DOT}
       {studentshots/2005/51004006Sa.jpg}\\
  \gap\htmladdnormallink{with Pit S\"utterlin at DSP cooling shed}
       {studentshots/2005/51006004S.jpg}\\

Mirte Kraaijkamp \& Ivana Sersic\\
 \gap\htmladdnormallink{in SST library}
       {studentshots/2005/mk+is-work.jpg}\\
 \gap\htmladdnormallink{in SST kitchen}
       {studentshots/2005/mk+is-cooking.jpg}\\
 \gap\htmladdnormallink{with Rob Hammerschlag in SST kitchen}
       {studentshots/2005/mk+is+rh.jpg}\\
 \gap\htmladdnormallink{with Anders Eriksson \& Rob Rutten in SST kitchen}
       {studentshots/2005/mk+is-pizza.jpg}\\
 \gap\htmladdnormallink{on the Roque}
       {studentshots/2005/mk+is-rdlm.jpg}\\
 \gap\htmladdnormallink{after manual data reduction}
       {studentshots/2005/mk+is-redhands.jpg}\\

Fedde Benedictus \& Daan van Eijk\\
  \gap\htmladdnormallink{with Rob Hammerschlag in SST library}
       {studentshots/2005/daan+fedde+rh.jpg}\\



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT students-2004 photos}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Selma de Mink \& Dagmar de Rooij\\
 \gap\htmladdnormallink{Selma with Rob Hammerschlag on the DOT}
       {studentshots/2004/selma+rh-dot.jpg}\\
 \gap\htmladdnormallink{with Pit S\"utterlin \&
       Sylvain Rondi at DOT control}
       {studentshots/2004/controlroom.jpg}\\
 \gap\htmladdnormallink{Selma at work with Luc Rouppe van der Voort 
       and Rob Rutten (taken by Dagmar)}
       {studentshots/2004/luc+selma+rob-work.jpg}\\
 \gap\htmladdnormallink{at work with Luc Rouppe van der Voort}
       {studentshots/2004/lr+sm+ddr.jpg}\\
 \gap\htmladdnormallink{Dagmar de Rooij giving a USO seminar}
       {studentshots/2004/dagmar-uso.jpg}\\
 \gap\htmladdnormallink{Rob Hammerschlag \& Luc Rouppe van der Voort at
        Dagmar's USO seminar}
       {studentshots/2004/rh+luc+dagmar.jpg}\\
 \gap\htmladdnormallink{Felix Bettonvil, Mats Carlsson \& Rob Hammerschlag
        at Dagmar's USO seminar}
       {studentshots/2004/fb+mc+rh.jpg}\\
 \gap\htmladdnormallink{with Govert Schilling and others at Grantecan}
       {studentshots/2004/grantecan-eyes.jpg}\\
 \gap\htmladdnormallink{Rob Rutten \& Selma at data mining
       (taken by Dagmar)}
       {studentshots/2004/rob+selma-splinter.jpg}\\
 \gap\htmladdnormallink{monitoring nighttime astronomers 
        at data gathering (taken by Anthony Horton)}
       {studentshots/2004/nighttime-beer.jpg}\\

Marcel Haas \& Jacob van Peet\\
 \gap\htmladdnormallink{at work}
       {studentshots/2004/vanpeet+haas2.jpg}\\
 \gap\htmladdnormallink{on the moon}
       {studentshots/2004/vanpeet+haas41009002S.jpg}\\
 \gap\htmladdnormallink{on the Roque}
       {studentshots/2004/vanpeet+haas-rdlm.jpg}\\
 \gap\htmladdnormallink{on leave, with Sylvain Rondi \& Rob Rutten}
       {studentshots/2004/rondi+vanpeet+haas+rr.jpg}\\


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{DOT detail:~ past,~ facts,~ technology,~ pictures}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT past}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

The design and construction of the DOT were funded by Sterrenwacht
Sonnenborgh and the \htmladdnormallink{Faculty of Physics and
Astronomy (UU Fac. N\&S)} {http://www.phys.uu.nl} of Utrecht
University during the 1970s and 1980s.  In the 1990s the
\htmladdnormallink{Dutch Technology Foundation STW}
{http://www.stw.nl} contributed significantly to the assembly and
installation on La Palma in order to evaluate the innovative DOT
technology and verify its open principle.

After the 
    \htmladdnormallink{first light ceremony}{dotshots/ceremony},
in 1997, a DOT science validation period was funded by the
  \htmladdnormallink{Sterrekundig Instituut Utrecht (SIU)}
         {http://www.astro.uu.nl}
and the 
  \htmladdnormallink{Utrecht University Faculty 
                     of Physics and Astronomy (UU Fac. N\&S)}
        {http://www.phys.uu.nl},
the 
  \htmladdnormallink{Netherlands Organization for Scientific Research (NWO)}
        {http://www.nwo.nl},
the
  \htmladdnormallink{Netherlands Research School for Astronomy (NOVA)}
        {http://www.strw.LeidenUniv.nl/nova},
and the 
  \htmladdnormallink{European Solar Magnetism Network (ESMN)}
        {http://esmn.astru.uu.nl}.
From 2004 to 2008 the DOT operation was funded by
  \htmladdnormallink{SIU,}
         {http://www.astro.uu.nl}
  \htmladdnormallink{UU Dept.~N\&S}
        {http://www1.phys.uu.nl},
  \htmladdnormallink{NWO,}
       {http://www.nwo.nl}
and
  \htmladdnormallink{NOVA}
        {http://www.strw.LeidenUniv.nl/nova}.

\par
Speckle restoration was initiated already during the first
science-oriented observing campaigns by P.~S\"utterlin who ported his
version of the G\"ottingen speckle code to the DOT.  Its spectacular
success led to the installation of a high-volume speckle acquisition
system which permits speckle restoration consistently at multiple
wavelengths simultaneously, using digital CCD cameras, two-way digital
fiber links to the Swedish telescope building,
control-plus-acquisition PC's, and a data storage system.  The
multi-channel optics design, involving
\htmladdnormallink{ASTRON at Dwingeloo}
{http://www.nfra.nl}, is discussed in \htmladdnormallink{Bettonvil et
al., SPIE 4853, 306, 2003} {rrweb/rjr-pubs/2003hawaii-dot.pdf}.
Here are \htmlimagelink{schematic}{dotshots/felix-multiwav}
{jpg}{pdf}{8cm}{90} and \htmlimagelink{detailed}
{dotshots/aswin-multiwav} {jpg}{pdf}{16cm}{0} design drawings.  The
hardware was constructed by the \htmladdnormallink{Utrecht
instrumentation group IGF} {http://www.phys.uu.nl/~wwwigf}.

\par
The DOT Speckle Processor funded by
\htmladdnormallink{NWO}{http://www.nwo.nl} went into full operation 
in 2006.  It processes the daily harvest of speckle data (up to
1.8 Terabyte) within a few days, reducing it hundred-fold to
speckle-reconstructed movies that can be distributed easily via the
internet through the \htmladdnormallink{DOT
database}{ftp://dotdb.phys.uu.nl/} and its
\htmladdnormallink{database search engine}
{http://dotdb.phys.uu.nl/search} 
and 
\htmladdnormallink{chronological database index}
{http://dotdb.phys.uu.nl/DOT}.

\par 
We ran the
\htmladdnormallink{DOT Student Program}{DOT_education.html}
during 2004 - 2007.  It brought two dozen students to La Palma for two
weeks of intensive on-the-spot research training.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT facts}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Optics\\
~~~Prime mirror (Cervit): aperture 45 cm, focal length 200~cm\\
~~~Quality: rms 0.011 micron = wavelength/50\\
~~~Prime-focus field stop (hole in water-cooled mirror): 1.6~mm\\
~~~Field of view: 150~arcsec
  
\par
Telescope\\
~~~Mount: parallactic, brushless push-pull pairs of servo motors\\
~~~Gears: 1:75000 reduction in four floating-gear steps\\
~~~Weight: 16 tons

\par
Tower\\
~~~Design: permits only parallel platform motion, no tilts\\
~~~Construction: open steel framework\\
~~~Height: 15 meter\\
~~~Weight: 13 tons

\par
Canopy\\
~~~Design: fold-away clam-like shell\\
~~~Construction: teflon-like--coated PVC fabric on heavy steel ribs\\
~~~Diameter: 7 meter

\par
Speckle acquisition system\\
~~~Cameras: Hitachi KP-F100 (1296~x~1030~px, 10 bit, 12 frames/s)\\
~~~Field of view: 92~x~73 arcsec, 0.071 arcsec/px
~~~Fiber links: dual way, custom made (IGF)\\
~~~Data storage: dual-processor 600 mHz Compaq PC's, 72~Gb RAID array each\\
%%~~~Data archive: Exabyte Mammoth-2 tape library (350~Gb)

\par
Old speckle processing system\\
~~~All (6 dual-processor 600 MHZ PC's) DOT computers on La Palma

\par
New speckle processing system\\
~~~see
   \htmladdnormallink{DOT speckle processor}{rrweb/dot-documents/dsp-2004.pdf}  

\par
Location\\
~~~Observatorio del Roque de los Muchachos\\
~~~Instituto de Astrof\'{\i}sica de Canarias\\
~~~Isla de La Palma, Spain\\
~~~The DOT is controlled from the SST building of the 
Institute for Solar Physics of the Royal Swedish Academy of Sciences

\par
Team\\
~~~Program leader: Prof. Dr. Christoph U. Keller (SIU)\\
~~~DOT scientist: Prof. Dr. Robert J. Rutten (SIU, ITA Oslo)\\
~~~DOT builder: Dr. Ir. Robert H. Hammerschlag (SIU)\\
~~~DOT engineer: Ir. Felix C.M. Bettonvil (Dept. N\&S)\\
~~~Software engineer: Drs. Guus Sliepen (STW)\\
~~~Technicians: Piet W. Hoogendoorn (IGF), Aswin J\"agers (STW)

\par
Construction\\
~~~Workshop Sterrekundig Instituut Utrecht\\
~~~Centrale Werkplaats Technische Universiteit Delft\\
~~~Instrumentele Groep Fysica Universiteit Utrecht

\par
Funding\\
~~~Sterrekundig Instituut Utrecht (Utrecht University)\\
~~~Department of Physics and Astronomy (Utrecht University)\\
~~~Utrecht University\\
~~~Netherlands Organization for Scientific Research (NWO)\\
~~~Netherlands Graduate School for Astronomy (NOVA)\\
~~~Stichting Technische Wetenschappen STW (NWO)\\
~~~Stichting ASTRON (NWO)\\
~~~European Solar Magnetometry Network (EC-TMR)\\
~~~European Solar Magnetism Network (EC-RTN)\\
~~~North Atlantic Treaty Organization (NATO-CRG)\\
~~~International Association INTAS\\
~~~Stichting Optisch Zonneonderzoek in Utrecht (SOZOU)\\
~~~Stichting N. van Ballegooijenfonds\\
~~~Pieter Langerhuizen Lambertuszoon Fonds



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT technology}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The DOT is a reflector with a parabolic mirror that sits out in the
open at a height of 15~m  
  \htmladdnormallink{(photograph)}{dotshots/neg19-may99.jpg}.
The mirror (presently Cervit, 45~cm
diameter, focal length 200~cm) 
focuses   
%%  \htmlimagelink{(photograph)}{dotshots/focus-mirror}
%%  {jpg}{pdf}{8cm}{0}
the incoming beam onto a water-cooled 1.6~mm field stop
%%  \htmlimagelink{(photograph)}{dotshots/focus}
%%  {jpg}{pdf}{8cm}{0}
that reflects most of the image out of the
telescope and transmits only a 2.5 by 2.5~arcmin subfield
to the re-imaging optics and cameras.

\par
The 15~m high support tower,
at a weight of 13 ton considerably
lighter than the telescope itself, permits only lateral motion of the
platform while inhibiting tilts.  
Even in strong wind buffeting the telescope therefore
maintains precise tracking.  The tower puts the telescope above the
turbulent boundary layer caused by solar ground heating, especially when
the strong trade wind blows up-slope from Northern directions 
in the "standard" best-seeing weather pattern.
The tower consists of open steel-tube triangles and is designed to
withstand large ice loads and wind pressure.  The ladder and elevator
cage may be filled by 30 tons of ice without harm!

\par
The bad-weather canopy
   \htmlimagelink{(photograph)}{dotshots/tent-delft}
    {jpg}{pdf}{12cm}{0}
opens clamshell-like and folds fully away to the sides.  
It is made of heavy polyester fabric mounted on steel ribs
and may be closed in winds up to 30~m/s (or opened, but 
that is less likely).  
When closed it should withstand the 70~m/s (Bf 12) winds that might
hit Roque de los Muchachos in the harsh La Palma winter storms.  
The coated fabric also tends to resist ice deposition
(otherwise a
major problem at the Canary Island mountain summits where undercooled
fogs often cause heavy upwind icicle growth.  The combination 
of massive ice loads with hurricane-strength storms is a major
building risk at the La Palma and Tenerife observatories.
A scaled-up copy of this canopy for the 
  \htmladdnormallink{German GREGOR project}
  {http://gregor.kis.uni-freiburg.de}
has been constructed at 
  \htmladdnormallink{DTO Delft}
                    {http://www.dto.tudelft.nl/index_en.htm}
under supervison of the DOT team. 

The tower, platform, telescope, and canopy were mounted on the La Palma
site during 1996-1997.  The optics were mounted in a full-size
interferometer at Utrecht in order to construct a precise major-axis
and focus defining laser system that guarantees high-precision
alignment.  It was used to define the optical axis exactly when the
mirror and secondary optics were installed.

\par
The mirror   
  \htmlimagelink{(photograph)}{dotshots/mirror-laser}
  {jpg}{pdf}{8cm}{0}
is mounted deformation-free with nine-point axial and 
three-point radial support in a parallactic telescope structure that is 
considerably overdimensioned as well as unbalanced in order to obtain 
extreme pointing stability at very low dissipation.  
The latter amounts to only about 20~W (three orders of magnitude 
less than the heat production of the oil bearings in the nearby 
William Herschel Telescope).
Brushless pairs of servo motors 
in push-pull preload configuration without backlash drive four-step
gear trains 
    \htmlimagelink{(photograph)}{dotshots/gears-piet}
    {jpg}{pdf}{8cm}{0}
achieving 1:75,000 reduction with self-aligning gears.

\par
The DOT top is constructed
with very stiff supports capable of carrying large weight.  The
resulting
   \htmlimagelink{DOT aperture}{dotshots/dot-aperture}
    {jpg}{pdf}{6cm}{0}
(shadow of the on-axis tube and support beams on the primary) 
is asymmetric; its unusual shape is accounted for
in the speckle processing.  Here is an
   \htmlimagelink{example of the DOT + speckle transfer function}
                 {dotshots/seeing-transfer}
    {jpg}{pdf}{8cm}{0}
(amplitude modulation transfer function averaged over many
 specklegrams).

\par
The DOT secondary optics consisted initially of on-axis re-imaging
lenses, focus mechanism, and analog video camera.  All DOT movies from
before April 2000 were made with this simple technology-demonstration
system.  Even at 8-bit digitization (with a PC frame grabber), speckle
reconstruction was found to be feasible and highly worthwhile.  
Science-grade data followed with the installation of digital
cameras (see \htmladdnormallink{DOT papers}
       {DOT_papers.html}).

\par 
Multi-channel observation was initiated by the installation
of a second camera (the first one mounted besides the incoming beam)
which observes continuum near the G-band and enables separation
of granular and fluxtube motions through image subtraction,
a technique that exploits the strict synchronicity of the DOT 
speckle imaging system (e.g.
\htmladdnormallink{Nisenson, van Ballegooijen, de Wijn \&
   S{\"u}tterlin, Ap.\ J. 587, 458, 2003}
       {rrweb/dot-publications/nisenson++2003.pdf}.

\par
In the meantime, an elaborate multi-wavelength system was designed
using six identical digital CCD cameras of which four are located,
each with its own optimised re-imaging optics, in the DOT top besides the
incoming beam.  Here is \htmlimagelink{the design for the complete DOT
top} {dotshots/HoekpuntD1B} {jpg}{pdf}{14cm}{0}.  Beam splitters
(including dichroic ones) divide the light between the G band (on-axis
tube and camera), a continuum band near the G band, Ca~II~H, Halpha, a
continuum band near Halpha, and Ba~II~4554.  
Detail is given in
\htmladdnormallink{2003hawaii-dot.pdf}
          {rrweb/rjr-pubs/2003hawaii-dot.pdf}.

\par
Interference filters are used for the continua, G band and Ca~II~H.
The Halpha beam utilises a Zeiss Lyot filter which can be tuned
rapidly through the line.  The similar but even narrower-band tunable
Lyot filter from Irkutsk may eventually provide Ba~II~4554
Dopplergrams in future.  The narrow-band filters are mounted with
telecentric re-imaging optics to produce bandpass homogeneity over the
full field at the full resolution given by the primary-mirror
diffraction limit at each wavelength.  The
\htmladdnormallink{digital cameras} {dotshots/kpf100.jpg} (Hitachi
KP-F100, 1296x1030~px, 10 bit, 6.7x6.7~micron pixel size) always run
in synchronous speckle mode, each obtaining 100--200 frame bursts at
up to 12~frames/s rate.  The digital speckle bursts are transported
per custom-made optical fiber links to the control room.  The
telescope and camera operation is also remotely controlled through
optical fibers.  For more detail see
\htmladdnormallink{Rutten et al., A\&A 413, 1183, 2004}
                  {rrweb/rjr-pubs/2004AAp...413.1183R.pdf}.

\par 
The continuum-near-Halpha and continuum-near-Ba~II~4554 speckle
registration serves for restoration following
\htmladdnormallink{Keller \& von der L\"uhe (1992)}
{http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1992A\%26A...261..321K}
%RR this needs \ for % or it won't latex for ps output; URL works!
In this multi-channel technique, the wide-band wavefront estimation is
used to restore the narrow-band frames that by themselves have
insufficient S/N within the exposure limit set by the 10ms seeing
freeze time.  An important advantage is that when multiple wavelengths
are chosen for the two Lyot filters (Halpha and Ba~II~454), these can
be taken in smaller subbursts to gain faster cadence and they will be
perfectly co-registered through rubber-sheet slaving to the single
wide-band channel speckle reconstruction.

\par
The  
  \htmladdnormallink{DOT control room}
                    {dotshots/DCP-5006.jpg}
is located in the nearby Swedish telescope building,
- where the DOT team enjoys generous
hospitality - and adjacent to the Swedish
(formerly the SVST, now the Swedish 1-m Solar Telescope SST)
control room and image laboratory.  Their proximity obviously
facilitates tandem operation of the two telescopes.

\par
The incoming speckle bursts are handled by a
\htmladdnormallink{multi-computer network}{dotshots/dot-network.jpg}
encompassing a control computer, 
    \htmladdnormallink{image-storing computers}
    {dotshots/rack5computers.jpg},
each with a 72~Gb RAID disk array, 
connections to the DOT Speckle Processor.


\par 
The sophisticated parallel
\htmladdnormallink{DOT Speckle Processor}{rrweb/dot-documents/dsp-2004.pdf}.
has 3.6~TByte storage capacity and delivers fast speckle processing
for data sets as large as eight-hour continuous registration with six
cameras (up to 1.8~TByte).  We use the DOT database for data
dissemination and aim to enable serving via the Virtual Solar
Observatory.



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT pictures}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

High-resolution photographs for use in publications are provided
under \htmladdnormallink{DOT photographs}{DOT_photographs.html}.\\
For DOT-student photographs see 
 \htmladdnormallink{DOT student program}{DOT_education.html}.

{\em June 2005:}\\
 \gap Darrel Torgerson: ~~\htmladdnormallink{DOT with Rob Hammerschlag}
       {dotshots/2005/torgerson-dot+rh-768.jpg}\\
 \gap Daan van Eijk: ~~\htmladdnormallink{DOT top}
       {dotshots/2005/dot-top50623042S.jpg}
   \gap\htmladdnormallink{DOT mirror}
       {dotshots/2005/dot-mirror2-50623048S.jpg}
   \gap\htmladdnormallink{DOT platform}
       {dotshots/2005/dot-platform-50623058S.jpg}
   \gap\htmladdnormallink{DOT cross-leg resonance damper}
       {dotshots/2005/dot-damper-50623056S.jpg}
   \gap\htmladdnormallink{DOT legs, shadow, data pipe, and SST}
       {dotshots/2005/dot-leg-pipe-sst-50623057S.jpg}\\
 \gap Sylvain Rondi: ~~\htmladdnormallink{DOT googled from above}
       {dotshots/2005/DOTgoogle.jpg}

{\em October 2004:}\\
 \gap\htmladdnormallink{DOT overview}
       {dotshots/2004/dot-overview.jpg} 
 \gap\htmladdnormallink{DOT in codeso}
       {dotshots/2004/dot+codeso.jpg}
 \gap\htmladdnormallink{DOT \& WHT in codeso}
       {dotshots/2004/dot+wht+codeso.jpg}
 \gap\htmladdnormallink{DOT \& WHT}
       {dotshots/2004/dot+wht-closeup.jpg}
 \gap\htmladdnormallink{DOT close-up}
       {dotshots/2004/DOT-closeup.jpg}\\
 \gap\htmladdnormallink{Rob Hammerschlag \& Felix Bettonvil at lunch}
       {dotshots/2004/hammerschlag+bettonvil.jpg}
 \gap\htmladdnormallink{Pit S\"utterlin at speckle}
       {dotshots/2004/suetterlin.jpg}\\
 \gap\htmladdnormallink{Rafael Kever opening up ATST seeing monitor}
       {dotshots/2004/atst-test-openup.jpg}
 \gap\htmladdnormallink{Rafael Kever and ATST seeing monitor}
       {dotshots/2004/atst-monitor-rafael-kever.jpg}\\
 \gap\htmladdnormallink{SST}
       {dotshots/2004/sst+building.jpg}
 \gap\htmladdnormallink{SST top}
       {dotshots/2004/sst-closer.jpg}
 \gap\htmladdnormallink{SST turret}
       {dotshots/2004/sst-turret.jpg}\\
 \gap\htmladdnormallink{Rolf Kever opening SST drive}
       {dotshots/2004/rolf-sst.jpg}
 \gap\htmladdnormallink{Rolf Kever \& Rob Hammerschlag repairing SST drive}
       {dotshots/2004/rk+rh-repairing.jpg}\\
 \gap\htmladdnormallink{Viggo Hansteen, Mats Carlsson \& 
         Luc Rouppe van der Voort in SST control room}
       {dotshots/2004/viggo+mats+luc.jpg}\\
 \gap\htmladdnormallink{Misty Magic}
       {dotshots/2004/magic-mist.jpg}
 \gap\htmladdnormallink{TNG}
       {dotshots/2004/galileo.jpg}
 \gap\htmladdnormallink{Grantecan}
       {dotshots/2004/grantecan.jpg}\\
 \gap\htmladdnormallink{Caldera at sunset}
       {dotshots/2004/caldera-clouds.jpg}\\

{\em Photographs by Sylvain Rondi, October 2004:}\\
  \gap\htmladdnormallink{Rob Hammerschlag opening up}
                        {dotshots/2004/rondi-rh.jpg}
  \gap\htmladdnormallink{DOT at sunset}
                        {dotshots/2004/rondi-sunset.jpg}
  \gap\htmladdnormallink{DOT at night}
                        {dotshots/2004/rondi-night.jpg}

{\em Installation of the Halpha filter, September 2004:}\\
  \gap\htmladdnormallink{Lyot filter in control box}
                        {dotshots/Ha-box-inside.jpg}
  \gap\htmladdnormallink{Mounted on DOT}
                        {dotshots/Ha-dot-kop.jpg}
  \gap\htmladdnormallink{DOT pointed at sun}
                        {dotshots/Ha-dot-pointed.jpg}
  \gap\htmladdnormallink{DOT top}
                        {dotshots/Ha-kop-top.jpg}

{\em During a Utrecht University site visit, August 2003:}\\
  \gap\htmladdnormallink{DOT seen from the SST}
                        {dotshots/UU-visit/UU-visit-30810007L.jpg}\\
  \gap\htmladdnormallink{Platform and telescope (taken by Henrik Rudolph)}
                        {dotshots/UU-visit/dot-kop-cut.jpg}
  \gap\htmladdnormallink{Platform from below (taken by Henrik Rudolph)}
                        {dotshots/UU-visit/platform-underside.jpg}\\
   \gap\htmladdnormallink{Mount and mirror}
                        {dotshots/UU-visit/UU-visit-30810059L.jpg}
  \gap\htmladdnormallink{Telescope top (taken by Henrik Rudolph)}
                        {dotshots/UU-visit/dot-top-cut.jpg}\\
  \gap\htmladdnormallink{Norbert Langer,
          Willem Hendrik Gispen, Will de Ruijter,
          Rob Hammerschlag \& Pit S\"utterlin 
          on the DOT platform}
                        {dotshots/UU-visit/UU-visit-30810067L.jpg}\\
  \gap\htmladdnormallink{Ed van den Heuvel, Werner van der Weg,
          \& G\"oran Scharmer}
                        {dotshots/UU-visit/UU-visit-30810009L.jpg}\\
  \gap\htmladdnormallink{Felix Bettonvil \& Rob Hammerschlag at the SST}
                        {dotshots/UU-visit/UU-visit-30810019La.jpg}\\
  \gap\htmladdnormallink{SST seen from the DOT, with DOT image pipe}
                        {dotshots/UU-visit/UU-visit-30810033L.jpg}\\
  \gap\htmladdnormallink{ATST site survey tower}
                        {dotshots/UU-visit/UU-visit-30810036L.jpg}

{\em During a KNVWS Werkgroep Zon visit, April 2003:}\\
  \gap\htmladdnormallink{Group assembly}
                        {dotshots/KNVWS-DOT-2003.jpg}

{\em Mounting more channels, March 2003:}\\
  \gap\htmladdnormallink{Multi-channel suppport}
                        {dotshots/new-base.jpg}
  \gap\htmladdnormallink{Multi-channel support with Bettonvil}
                        {dotshots/new-base+Felix.jpg}
  \gap\htmladdnormallink{Multi-channel support with Aswin J{\"a}gers}
                        {dotshots/new-base+Aswin.jpg}\\
  \gap\htmladdnormallink{Four-channel optics complete}
                        {dotshots/new-4channel.jpg}
  \gap\htmladdnormallink{Six-hand four-camera cabling}
                        {dotshots/new-cabling.jpg}

{\em Utrecht,~DOT~speckler~definition,~November~2002:}\\
  \gap\htmladdnormallink{Alfred~de~Wijn~+~sketch}
     {\astronomershots/siu2002/speckle-session-pict0001.jpg}
  \gap\htmladdnormallink{Aad~van~der~Steen}
     {\astronomershots/siu2002/speckle-session-pict0004.jpg}
  \gap\htmladdnormallink{Felix~Bettonvil}
     {\astronomershots/siu2002/speckle-session-pict0007-rot.jpg}
  \gap\htmladdnormallink{Pit~S{\"u}tterlin}
     {\astronomershots/siu2002/speckle-session-pict0008-rot.jpg}
  \gap\htmladdnormallink{Michiel~van~Noort}
     {\astronomershots/siu2002/speckle-session-pict0010-rot.jpg}
  \gap\htmladdnormallink{result}
     {\astronomershots/siu2002/speckle-session-pict0014-rot.jpg}

{\em Observing after snow, April 2002:} \\
  \gap\htmladdnormallink{Roque de los Muchachos overview}
                        {dotshots/DCP_4933.jpg}
  \gap\htmladdnormallink{DOT, WHT, SST: three very different telescopes}
                        {dotshots/DCP_4964.jpg}\\
  \gap\htmladdnormallink{DOT with ice}
                        {dotshots/iced-dot.jpg}
  \gap\htmladdnormallink{DOT ladder with ice}
                        {dotshots/Dcp_4927v.jpg}\\
  \gap\htmladdnormallink{DOT top within closed canopy}
                        {dotshots/DCP_4999.jpg}
  \gap\htmladdnormallink{DOT, WHT, SST during solar observing}
                        {dotshots/DCP_4981.jpg}
  \gap\htmladdnormallink{DOT pointed at the sun}
                        {dotshots/DCP_4985.jpg}
  \gap\htmladdnormallink{DOT pointed at the sun: cutout}
                        {dotshots/DCP_4985-cut.jpg}\\
  \gap\htmladdnormallink{Open DOT with Bettonvil \& S\"utterlin}
                        {dotshots/Dcp_4997r.jpg}\\
  \gap\htmladdnormallink{S\"utterlin observing the 
                        camera in DOT control room}
                        {dotshots/DCP_5004.jpg}
  \gap\htmladdnormallink{S\"utterlin observing the sun in DOT control room}
                        {dotshots/DCP-5006.jpg}

{\em Darrel Torgerson's 2001 DOT photographs:}\\
%% copied from 
%%   \htmladdnormallink{http://www.lmsal.com/LaPalma}
%%                     {http://www.lmsal.com/LaPalma}: \gap
%RR bad advertising for us, so out
  \gap\htmladdnormallink{DOT with sunrise mountain shadow}
                        {dotshots/dot+shadow.jpg}
  \gap\htmladdnormallink{DOT with low sun}
                        {dotshots/dot+sun.jpg}
  \gap\htmladdnormallink{DOT in full glory}
                        {dotshots/glory-small.jpg}\\
  \gap\htmladdnormallink{DOT with setting sun}
                        {dotshots/dot-sunset1.jpg}
  \gap\htmladdnormallink{DOT with binary sun}
                        {dotshots/dot-sunset2.jpg}\\
  \gap\htmladdnormallink{DOT with green flash}
                        {dotshots/greenfl-small.jpg}
  \gap\htmladdnormallink{DOT with clouds}
                        {dotshots/dot+clouds.jpg}

%% add CaHmontage.jpg

{\em Data-acquisition system, February 2001:}\\
  \gap\htmladdnormallink{Hammerschlag mounting a filter}
     {dotshots/filtermontage.jpg}\\
  \gap\htmladdnormallink{New G-band channel (on-axis tube)}
     {dotshots/neg8-feb01.jpg}
  \gap\htmladdnormallink{Close-up of G-band tube}
     {dotshots/neg16-feb01.jpg}
  \gap\htmladdnormallink{Close-up of prime focus}
     {dotshots/neg7-feb01.jpg}\\
  \gap\htmladdnormallink{Fiber connectors on DOT}
     {dotshots/fiberachter.jpg}
  \gap\htmladdnormallink{Fiber exits in Swedish building}
     {dotshots/fiberkastcr.jpg}\\
  \gap\htmladdnormallink{Five-computer image acquisition rack}
     {dotshots/neg22-dec00.jpg}\\
  \gap\htmladdnormallink{UPS (safeguard against lightning damage)}
     {dotshots/ups.jpg}


\par
{\em Mechanical structure, 1999--2001:}\\
  \gap\htmladdnormallink{DOT with cooling water tank \& pipe}
     {dotshots/neg19-may99.jpg}
  \gap\htmladdnormallink{DOT on its platform}
     {dotshots/neg8-may99.jpg}
  \gap\htmladdnormallink{Close-up of DOT on platform}
     {dotshots/neg14-may99.jpg}\\
  \gap\htmladdnormallink{DOT drives}
     {dotshots/telescoop.jpg}
  \gap\htmladdnormallink{DOT primary}
     {dotshots/spiegel.jpg}\\
  \gap\htmladdnormallink{Tower bottom with workshops}
     {dotshots/dotplaats.jpg}
  \gap\htmladdnormallink{Tower bottom with workshops}
     {dotshots/neg21a-dec00.jpg}
  \gap\htmladdnormallink{Tower bottom with fallen ice}
     {dotshots/lift+ijs1.jpg}


\par
{\em In less good weather, October 1999:}\\
  \gap\htmladdnormallink{DOT open, with water tank}
     {dotshots/dot01.jpg}
  \gap\htmladdnormallink{DOT top, with prime focus tube}
     {dotshots/dot06.jpg}\\
  \gap\htmladdnormallink{Primary mirror (covered) with declination wheel,
      support struts, guider scope}
     {dotshots/dot07.jpg}\\
  \gap\htmladdnormallink{Mirror with strut connectors, suction hose}
     {dotshots/dot08.jpg}\\
  \gap\htmladdnormallink{Hour-angle wheel and mirror support}
     {dotshots/dot09.jpg}\\
  \gap\htmladdnormallink{Seykora-Beckers scintillometer 
         with anti-falcon needle}
     {dotshots/dot12.jpg}\\
  \gap\htmladdnormallink{Data pipeline to the Swedish building}
     {dotshots/dot13.jpg}\\
  \gap\htmladdnormallink{R. Hammerschlag in his telescope}
     {dotshots/dot17.jpg}
  \gap\htmladdnormallink{R. Hammerschlag as DOT surgeon}
     {dotshots/dot18.jpg}\\
  \gap\htmladdnormallink{C. Denker, Ph. Goode, L. Strous, R. Hammerschlag}
     {dotshots/dot04.jpg}
  \gap\htmladdnormallink{R. Hammerschlag, F. Bettonvil, F. Paletou}
     {dotshots/dot23.jpg}
  \gap\htmladdnormallink{R. Hammerschlag, F. Bettonvil, G. Molodij}
     {dotshots/dot25.jpg}\\
  \gap\htmladdnormallink{SVST from DOT, F. Bettonvil on the ladder}
     {dotshots/dot26.jpg}
  \gap\htmladdnormallink{DOT closed, R. Hammerschlag on the ladder}
     {dotshots/dot31.jpg}\\
  \gap\htmladdnormallink{Clouds over DOT and WHT}
     {dotshots/dot29.jpg}
 

\par
{\em During optics tests, November-December 1997:}\\
  \gap\htmladdnormallink{DOT pointed at the sun}{dotshots/dot-dec97.jpg}
  \gap\htmladdnormallink{DOT close-up}{dotshots/dot-closeup-dec97.jpg}
  \gap\htmladdnormallink{DOT at sunset in Sahara dust}
                    {dotshots/dot_sunset_1997.jpg}

\par
{\em At the First Light Ceremony, October 31, 1997:} \\
  \gap\htmladdnormallink{Site overview looking North}
                    {dotshots/img0047.jpg}
  \gap\htmladdnormallink{DOT and WHT: two telescopes sharing royal interest}
                    {dotshots/dot-wht.jpg}\\
  \gap\htmladdnormallink{G. and R. Hammerschlag,
                C. van Scheijndel,
                E. van der Zalm,
                T. van Schie, 
                F. Bettonvil}{dotshots/dot-team.jpg}
  \gap\htmladdnormallink{J. Carlos Torres 
           and L. P\'{e}rez Machin with champagne}
                    {dotshots/leo-juan.jpg}\\
  \gap\htmladdnormallink{V. Martinez Pillet, O. von der L\"uhe}
                    {dotshots/valentin-oskar.jpg}
  \gap\htmladdnormallink{J. van Himbergen, F. van den Beemt}
                    {dotshots/vhimbergen-vdbeemt.jpg}\\
  \gap\htmladdnormallink{J. Veldhuis, 
                     W. Bentinck van Schoonheten,
                     J. Ritzen, 
                     M. Hermoso Rojas,
                     Prins Willem-Alexander van Oranje}
                     {dotshots/big-shots-row.jpg}\\
  \gap\htmladdnormallink{Speech by R. van Duinen}
                    {dotshots/speech-vanduinen.jpg}
  \gap\htmladdnormallink{Speech by J. Veldhuis}
                    {dotshots/speech-veldhuis.jpg}
  \gap\htmladdnormallink{Speech by J. Ritzen}
                    {dotshots/speech-ritzen.jpg}\\
  \gap\htmladdnormallink{DOT First Light Ceremony
                         performed by Prins Willem-Alexander and M. Hermoso
                         Rojas}
                    {dotshots/ceremony.jpg}\\
  \gap\htmladdnormallink{Prins Willem-Alexander 
                         and R. Hammerschlag in DOT elevator}
                    {dotshots/prince-RH.jpg}

\par
{\em Within the canopy, 1997:}\\
  \gap\htmladdnormallink{DOT mirror + focus}{dotshots/focus-mirror.jpg}
  \gap\htmladdnormallink{DOT mirror + laser}{dotshots/mirror-laser.jpg}
  \gap\htmladdnormallink{DOT mirror covered, with Rob Hammerschlag}
        {dotshots/hammerschlag_mirror_1998.jpg}\\
  \gap\htmladdnormallink{DOT focus}{dotshots/focus.jpg}
  \gap\htmladdnormallink{DOT focus with Felix Bettonvil}
         {dotshots/felix-focus.jpg}\\
  \gap\htmladdnormallink{DOT with ghosts}
         {dotshots/test_focus_jokers_bw.jpg}

\par
{\em On La Palma, 1996:}\\
  \gap\htmladdnormallink{DOT on its tower, with Anke and Rob Hammerschlag}
        {dotshots/dot-anke.jpg}\\
  \gap\htmladdnormallink{DOT and SVST}
        {dotshots/dot-open-svst.jpg}
  \gap\htmladdnormallink{DOT as part of the skyline}
        {dotshots/dot-rdlm-skyline.jpg}\\
  \gap\htmladdnormallink{DOT platform hoisting}
        {dotshots/hoisting_platform_1996.jpg}
  \gap\htmladdnormallink{DOT tower fastening}
        {dotshots/workers_dotlegs_1996.jpg}\\
  \gap\htmladdnormallink{DOT christening ceremony}
        {dotshots/balloons.jpg}

\par
{\em In Delft, 1990 - 1996:}\\
  \gap\htmladdnormallink{DOT clamshell canopy}{dotshots/tent-delft.jpg}\\
  \gap\htmladdnormallink{DOT builder Rob Hammerschlag and his telescope}
        {dotshots/dot-delft-rob.jpg}\\
  \gap\htmladdnormallink{DOT technician Piet Hoogendoorn with DOT gears}
        {dotshots/gears-piet.jpg}

\par
{\em On paper, 1975:}\\
  \gap\htmladdnormallink{DOT sketch}{dotshots/dot-reversed-sketch.jpg}



Mar  5 2009 USO traineeship out
===============================

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{DOT vacancies}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Presently we offer a six-month traineeship in on-site DOT observing,
data reduction and data analysis to recent graduates in astronomy,
physics, technical physics, or informatics.~ You will spend most of
the time on La Palma as principal DOT observer in control of the
telescope and its advanced speckle reconstruction computer farm.  The
prefered time slot is May through October 2009.  

The traineeship is funded by a grant from the EC to the
\htmladdnormallink{Utrecht-Stockholm-Oslo Collaboration in Solar Physics}
{http://www.solarphysics.kva.se/uso-est}.~ The grant includes generous
travel funding in addition to your salary and relocation expenses.~
The conditions are that you possess a degree entitling you to
post-graduate PhD study obtained within the last four years at the
time of hiring, but no PhD yet, and that you have non-Dutch and
non-Spanish nationality.  You must also have a driving license and be
capable and willing to drive up and down the Roque de los Muchachos
mountain in daily commute (about half an hour, but 360 turns).

Information and applications: email to <R.J.Rutten
\htmladdnormallink{at}{http://www.herodios.com/atsign.htm}
uu[dot]nl> specifying your background and qualifications
(as plain text, .ps, .pdf or .tex, but no .doc or .html).



Feb  7 2008 subsections movies, images, photographs  out

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT movies}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\htmladdnormallink{Thumbnail index album of all DOT movies}
                  {albums/movies/album.html}

\htmladdnormallink{Index to older DOT movies}
        {http://dotdb.phys.uu.nl/DOT/Showpiece/movies.html}

July 13, 2005: quartet movies of a small single sunspot with
umbral dots and running penumbral waves during nearly
three hours.~  The central clock equals the Earth
(12750~km = 17.5 arcsec).\\
~~~~~~~\htmladdnormallink{G band, Ca~II~H wing, Halpha wing, Halpha core}
          {albums/movies/2005-07-13-AR10789-gb+caw+haw+hac.mov}\\
~~~~~~~\htmladdnormallink{G band, Ca~II~H wing, Halpha core, Halpha
Dopplershift} {albums/movies/2005-07-13-AR10789-gb+caw+hac+had.mov}\\
~~~~~~~\htmladdnormallink{G band, Halpha wing, Halpha core,
Halpha Dopplershift} {albums/movies/2005-07-13-AR10789-gb+haw+hac+had.mov}

July 7-9, 2005: multi-wavelength movies of fairly complex active region 
AR10786 including a co-aligned extreme ultraviolet one from TRACE.\\
~~~~~~~~\htmladdnormallink{G band, Halpha, Ca~II~H, Halpha-Dopplershift}
   {albums/movies/2005-07-07-AR10786-gb+hac+haw+had.mov}\\
~~~~~~~~\htmladdnormallink{morph between Halpha-Dopplershift and G-band}
   {albums/movies/2005-07-09-AR10786-morph-had-gb.mov}\\
~~~~~~~~\htmladdnormallink{G band, Halpha, Halpha-Dopplershift, Fe 171}
   {albums/movies/2005-07-09-AR10786-gb+hac+had+171.mov}

October 2004: four synchronous quartet Halpha movies. \\ 
The central clock equals the Earth (12750~km = 17.5 arcsec).\\ 
~~~~~~~\htmladdnormallink{October 6: filament in G band,
Ca~II~H, Halpha wing, Halpha core}{albums/movies/2004-10-06-filament-gb+ca+haw+hac.mov}\\
~~~~~~~\htmladdnormallink{October 15: filament in G band,
Ca~II~H, Halpha wing, Halpha core}{albums/movies/2004-10-15-filament-gb+ca+haw+hac.mov}\\
~~~~~~~\htmladdnormallink{October 16: AR10682 in G band, Ca~II~H, Halpha
core, Halpha Dopplershift}{albums/movies/2004-10-16-AR10682-gb+ca+hac+had.mov}\\
~~~~~~~\htmladdnormallink{October 16: AR10682 in Halpha red and blue
   far and inner wings}{albums/movies/2004-10-16-AR10682-4xhaw.mov}

June 8, 2004: \htmladdnormallink{DOT movies of the Venus transit}
                  {DOT_Venus.html}

June 18, 2003: four quiet-sun Ca~II~H movies.\\
~~~~~~~\htmladdnormallink{disk center: blue continuum, G band, Ca~II~H wing,
         Ca~II~H core}{albums/movies/2003-06-18-QS-mu098-bc+gb+caw+cac.mov}\\
~~~~~~~\htmladdnormallink{near limb: blue continuum, G band, Ca~II~H wing,
         Ca~II~H core}{albums/movies/2003-06-18-QS-mu034-bc+gb+caw+cac.mov}\\
~~~~~~~\htmladdnormallink{near limb: Ca~II~H core}
           {albums/movies/2003-06-18-QS-mu034-ca-core.mov}\\
~~~~~~~\htmladdnormallink{near limb: Ca~II~H wing}
           {albums/movies/2003-06-18-QS-mu034-ca-wing.mov}

You are welcome to produce your own movies from the data cubes in the
\htmladdnormallink{DOT database}{DOT_data.html}.~  We will be grateful for
copies.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT images}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\htmladdnormallink{Thumbnail index album of DOT images}
     {albums/images/album.html}

More DOT images are provided via the
\htmladdnormallink{search engine}
{http://dotdb.phys.uu.nl/search}  and the
\htmladdnormallink{chronological index}
{http://dotdb.phys.uu.nl/DOT} to the \htmladdnormallink{DOT
database}{ftp://dotdb.phys.uu.nl}.  You are also welcome to produce
your own from the data cubes in the
\htmladdnormallink{DOT database}{DOT_data.html}.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT photographs}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\htmladdnormallink{Thumbnail index album of high-resolution DOT photographs} 
     {albums/photographs/album.html}

If you need PostScript files for insertion in LaTeX you
may produce them from e.g.\ .tif files under the link above
with the Unix/Linux command:\\
~~~~~~~~convert~~~~-geometry~~{\em X}~x~{\em Y}~~~~file.tif~~~~file.ps\\
where {\em X} and {\em Y} are the pixel sizes of the image.

More photographs of the DOT and DOT team members are provided under
\htmladdnormallink{DOT pictures}{DOT_pictures.html}.  

Photographs of DOT students are posted under
\htmladdnormallink{DOT students 2004}{DOT_students_2004.html},
~\htmladdnormallink{DOT students 2005}{DOT_students_2005.html},
~\htmladdnormallink{DOT students 2006}{DOT_students_2006.html},
~\htmladdnormallink{DOT students 2007}{DOT_students_2007.html}.





Jan 27 2007 subsections future and collaborations taken out


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT future}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

By working down our 
\htmladdnormallink{to-do project list}
                  {DOT_projects.html} the DOT has become a
multi-wavelength tomographic imager with excellent science
capabilities, by itself but also of large value to many comprehensive
solar physics observing programs at the present time in which SOHO,
TRACE and Hinode provide complementary solar data from space.

With 
\htmladdnormallink{DOT++ aperture}{dot-publications/spie-5489-99.pdf} 
and speckle system triplings, the DOT may remain a highly worthwhile
0.07~arcsec tomographic wide-field imager for almost every
observational solar physics program throughout the coming decade.


%%\par
%%The first DOT observing
%%(September 1999) was part of a joint campaign on sunspot dynamics with
%%three other Canary Island telescopes and the
%%   \htmladdnormallink{SOHO}
%%           {http://sohowww.nascom.nasa.gov/}
%%and 
%%\htmladdnormallink{TRACE}
%%           {http://vestige.lmsal.com/TRACE/}
%%missions.
%%Other campaigns followed, also using Ca~II~H and Halpha filters
%%in actual DOT observing runs as tests of the pertinent optics
%%designs.
%%The resulting image sequences can be inspected in the
%%  \htmladdnormallink{DOT database}
%%        {http://dotdb.phys.uu.nl/DOT/}
%%and on the
%%  \htmladdnormallink{DOT movies page}
%%        {http://dotdb.phys.uu.nl/DOT/Showpiece/movies.html}.
%%An overview is given 
%%  \htmladdnormallink{here}
%%        {dot-presentations/pit-dec.pdf}.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT collaborations}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
We often run the DOT in international campaigns as part of
\htmladdnormallink{Open DOT time allocation}{DOT_time.html}.
In addition we are formally part of the EC-funded consortia
described below.
%% no blank here
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsubsection{Utrecht-Stockholm-Oslo collaboration in solar physics}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The DOT team participates in the 
\htmladdnormallink{Utrecht-Stockholm-Oslo Collaboration
in Solar Physics} {dot-documents/uso-sp.pdf} which combines the solar
physicists at:
\begin{itemize}
  \item Sterrekundig Instituut
        \htmladdnormallink{SIU}
           {http://www.astro.uu.nl},
        Utrecht, The Netherlands 
  \item Institute for Solar Physics,
     \htmladdnormallink{KVA}{http://www.astro.su.se/groups/solar/solar.html},
        Stockholm, Sweden
  \item Institute of Theoretical Astrophysics
        \htmladdnormallink{ITA}{http://www.astro.uio.no/ita/english.html},
        Oslo, Norway
\end{itemize}
The mission of this USO-SP collaboration is to advance solar physics
combining the major assets of the three institutes:
\begin{itemize}
  \item  Utrecht's Dutch Open Telescope
  \item Stockholm's Swedish 1-m Solar Telescope
  \item Oslo's expertise in numerical simulation
\end{itemize}
One activity is our joint USO-SP Graduate School in Solar
Physics funded by the EC,
see the 
\htmladdnormallink{USO-EST website}{http://www.solarphysics.kva.se/uso-est}.

\subsubsection{European Solar Magnetism Network}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The DOT team coordinated the ESMN network which was part of 
the Fifth Framework Programme of the EU administered by
the European Commission (2002-2006) and was previously part of the
Fourth Framework TMR Programme (1998-2002).

The ESMN advanced the understanding of solar magnetism by
integrating the usage of the European solar telescopes on the Canary
Islands, the usage of ESA's SOHO mission, and pertinent data
interpretation and analysis.

\par
The ESMN partners were:
\begin{itemize}
  \item Sterrekundig Instituut
        \htmladdnormallink{SIU}
           {http://www.astro.uu.nl},
        Utrecht, The Netherlands (coordination)
  \item Instituto de Astrof\'{\i}sica de Canarias
        \htmladdnormallink{IAC}{http://www.iac.es},
        La Laguna, Spain
  \item Osservatorio Astrofisico di Arcetri
        \htmladdnormallink{OAC}{http://www.arcetri.astro.it},
        Florence, Italy
  \item Institute of Theoretical Astrophysics
        \htmladdnormallink{ITA}{http://www.astro.uio.no/ita/english.html},
        Oslo, Norway
  \item Institute for Solar Physics,
     \htmladdnormallink{KVA}{http://www.astro.su.se/groups/solar/solar.html},
        Stockholm, Sweden
  \item Astrophysikalisches Institut
        \htmladdnormallink{AIP}{http://aipsoe.aip.de},
        Potsdam, Germany
  \item Observatoire de Paris
        \htmladdnormallink{LESIA/DASOP}{http://www.dasop.obspm.fr},
        Meudon, France
  \item ESA Space Science Department
        \htmladdnormallink{ESTEC}{http://www.estec.esa.nl},
        Noordwijk, The Netherlands
  \item Astronomical Institute of the Czech Academy of Sciences,
        \htmladdnormallink{ASU}{http://www.asu.cas.cz},
        Ondrejov, Czech Republic
  \item Astronomical Institute of the Slovak Academy of Sciences,
        \htmladdnormallink{AISAS}{http://www.ta3.sk/homepage.html},
        Tatranska Lomnica, Slovakia
  \item Department of Astronomy E\"otv\"os University
        \htmladdnormallink{ELTE}{http://astro.elte.hu},
        Budapest, Hungary
\end{itemize}
The EC funded postdoc positions at each Western partner and supported
many collaborations including joint multi-telescope observing
campaigns.  More detail on the \htmladdnormallink{ESMN
pages}{http://esmn.astro.uu.nl}.


Sep 30 2006
============
%% presentations taken out (too old)


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsection{DOT presentations}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
These are links to selected DOT presentations, in time-reverse order,
all in pdf.  

Some presentations are not linearly arranged (as in Powerpoint
presentations, of which the order fixation resembles returning to the
ancient pre-viewgraph days of slide-tray lecturing) but are randomly
clickable, as with a browser, with blue clickables opening new
displays and with the display titles functioning as back button.
However, many clickable links to blowups, images, and movies won't
work for you.

\htmladdnormallink{Invited talk IAU Symposium 223, StPetersburg, June 2004}
                  {rjr-presentations/stpetersburg.pdf}

\htmladdnormallink{General Physics Colloquium, Utrecht, February 2004}
                  {rjr-presentations/faccol2004.pdf}

\htmladdnormallink{Oral presentation to Research Visitation Committee,
                   Faculty of Physics and Astronomy,
                   Utrecht, September 2003}
                  {dot-presentations/visitation2003.pdf}

%%\htmladdnormallink{Oral presentation of DOT++ preproposal to NOVA2
%%                   Advisory Committee,                     
%%                   Spier, October 2002}
%%                  {dot-presentations/nova2-spier.pdf}

\htmladdnormallink{Oral presentation collection from talks in 2002}
                  {dot-presentations/wwwdot2002.pdf}

\htmladdnormallink{Poster presentation on the EC/RTN ESMN network, 
                   Santorini conference, June 2002}
                  {dot-presentations/nac2002-esmn.pdf}

\htmladdnormallink{Poster presentation on parallel processing for the DOT, 
                   Nederlandse Astronomenconferentie, May 2002}
                  {dot-presentations/nac2002-dot.pdf}

\htmladdnormallink{Poster presentation on sunspot penumbral structure,
                   Nederlandse Astronomenconferentie, May 2002}
                  {dot-presentations/nac2002-pit-a.pdf}

\htmladdnormallink{Poster presentation on DOT results,
                   Nederlandse Astronomenconferentie, May 2002}
                  {dot-presentations/nac2002-pit-b.pdf}

\htmladdnormallink{Oral presentation to DOT Evaluation Committee, 
                   March 2001}
                  {dot-presentations/pit-dec.pdf}

\htmladdnormallink{Poster presentation on DOT magnetometry,
                   XIIth Canary Island Winter School, November 2000}
                  {dot-presentations/xiiwin_pit.pdf}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\subsubsection{EC-funded PhD studentships}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Thanks to an EST grant from the EC to the
\htmladdnormallink{Utrecht-Stockholm-Oslo Collaboration in Solar Physics}
  {dot/Utrecht_Stockholm_Oslo_coll.html} we offer fully funded
four-year graduate studentships to obtain a PhD at
      Utrecht University in solar astrophysics in DOT-oriented
      research.  Starting date: until February 1, 2007.

The conditions are that you possess a graduate degree entitling you to
post-graduate PhD study obtained within the last four years, and that you have European (EC or Associate
Country) but non-Dutch nationality.  The grant includes travel funding
in addition to your salary and relocation expenses.  Information and
applications: email to <R.J.Rutten
\htmladdnormallink{at}{http://www.herodios.com/atsign.htm}
astro.uu.nl> specifying your background, qualifications and interests
(as plain text, .ps, .pdf or .tex, but no .doc or .html).

The USO-EST coordinator is Dr. Dan Kiselman at Stockholm.  He
maintains \htmladdnormallink{the USO-EST
website}{http://www.solarphysics.kva.se/uso-est}.


