HOP 0025

abstract of observational proposal

The goal of our campaign is an understanding of the dynamic quiet sun
magnetic and of its coupling from the photosphere to the chromosphere.

We will acquire spectro-polarimetric data from the SST, the VTT, and
THEMIS. At the VTT will use the spectropolarimeter TIP and POLIS to measure
the deep photosphere (Fe I 1564.8 nm), the middle photosphere (Fe I 6302
nm), and the chromosphere (intensity profiles of Ca II H
397 nm). At THEMIS we will concentrate on the infrared Ca lines
(849.8 nm, 854.2 nm) to study the chromospheric response on photospheric
magnetic field. For alignment we will also record a photospheric line like
Fe I 525.0 nm at THEMIS. At the SST we will take advantage of the tunable
filter imaging system to obtain context information (images and
magnetograms) at highest possible resolution.
This multi-wavelength approach will be complemented with speckle-
reconstructed Halpha images from DOT.

For this campaign it would be of great advantage to complement the data set
with spectro-polarimetric data at 0.3'' spatial resolution (at the VTT we
may achieve a spatial resolution of only 0.5'' at best with the help of the
adaptive optics system).

request to SOT

We would propose to use the SP instrument in SOT to
measure the photospheric magnetic field with the line pair at 630.2 nm.
Additional Filtergram observations with SOT would be necessary for doing the
alignment with the ground- based data.

We propose to perform a time series of rather short scans with a high
repetition cadence of about 2 minutes at disk center. With an exposure time
of 4.8 seconds and a step size of 0.16'' the scan would amount to some 4''.
That means that alignment is an issue. But since the slit of SP is 160'',
there should be enough room for overlapping field of views.

remarks

The ITP campaign team consists of myself (Rolf Schlichenmaier, KIS,
Germany) as the Principal Investigator and includes Luis Bellot Rubio (IAA,
Spain), Christian Beck (IAC, Spain), Thomas Hillberg (SST, Sweden), Bruce
Lites (HAO, USA), Oskar von der Luehe (KIS, Germany), Gautam Narayan (SST,
Sweden), Reza Rezaei (KIS, Germany), Wolfgang Schmidt (KIS, Germany),
Alberto Sainz Dalda (IAC, Spain), Oskar Steiner (KIS, Germany), and Peter
Suetterlin (DOT).