*Title: Dynamics and structure of the solar atmosphere from SUMER and
        VTT observations

*Short title: Solar atmosphere: dynamics and structure

*Authors:

PI: Regina Aznar Cuadrado  (1)
    Luca Teriaca           (1) 

    
(1) MPS Lindau, Germany

Contact: aznar(at)mps.mpg.de

*Participating instruments and observatories:

SOHO/SUMER    (poc Luca Teriaca teriaca(at)mps.mpg.de)
SOHO/MDI
VTT           
TRACE

*Scientific Justification

To fully understand the dynamics and structuring of the solar magnetised
atmosphere it is necessary to find the relationship between the magnetic
structures in the photosphere (as obtained by VTT and MDI) and in the upper
chromosphere (VTT) with VUV radiance images (TRACE, EIT) of the 1 MK corona
and velocities measured in VUV lines formed at transition region and
coronal temperatures (SUMER). In this way it is possible to uncover the
transition region and coronal signatures associated with the magnetic field
at different layers in the atmosphere. Since the magnetic field is already
very close to force free at the level where the He 1083.0 triplet is formed
(in contrast to the photosphere, where most observations are carried out),
the magnetic structure deduced from this line should be much more closely
related to transition region and coronal structures and dynamics.

We propose to study the relationship between the structures and flows
observed in transition region with the full magnetic vector at the
chromospheric and photospheric levels as obtained from the inversion of the
spectropolarimetric data by observing both active and quiet Sun regions,
preferably close or at disc centre.

*Date and Time Information:

Observations to be run during the April 2009 Hinode/SUMER campaign. A run
lasts about four hours. To be run twice.  It need to be during VTT
observing time.

*Targeting  Requirements:

Target will be an active region near disc centre. If not available, it will
be quiet Sun at disc centre. If MDI/HiRes is available, we would like to be
within its FOV.

*Detailed Observing Sequences per Instrument

SUMER: 
Spectral windows including continuum around 141.0 nm, Si IV 139.3 nm
(T = 9x10^4 K), O VI 103.2 nm (T = 3x10^5 K) and Ne VIII 77.0 nm
(T = 6.3x10^5 K). Repeated raster scans of a 120"x120" area. 
Use 1" wide slit on QS and 0.3" slit on AR.
Total duration about 4 hours.

TRACE: 
In case of quiet Sun targets, take images at 155 nm every 30 s. 
In case of active region targets, take images at 17.1 nm every 30 s. 
FOV of 350"x350" (full resolution).

SOHO/MDI: high resolution magnetograms would be very valuable.

VTT: Spectropolarimetric scans in the He I 1083 nm multiplet and
Goettingen FPI co-observations in H-alpha.