Title    Structure and Dynamics of the Chromosphere
Pi     A. O. Benz
Time   10 hrs
1.  Structure and Dynamics of the Chromosphere

Arnold O. Benz, Tim S. Bastian, Sami K. Solanki

2. Most of the sub-millimeter emissions of the quiet sun originates from the
 low chromosphere. It is a thin layer above the temperature minimum
region, where non-radiative heating first becomes manifest. Detailed
semi-empirical models have been constructed. However, it has become
apparent in recent years that these models must be thoroughly revised
to reflect the highly inhomogeneous and dynamic nature of the
chromosphere. Moreover, the models do not contain the physics of the
heating process believed to be waves, shocks, thermal conduction,
electromagnetic phenomena (flare-like events) or a combination
thereof. The analysis of dynamical simulations predicts that the radio
emission at millimeter and submillimeter wavelengths is extremely
sensitive to the dynamic processes in the chromosphere, if these are
spatially resolved. The opposing view predicts heating mostly by weak
wave turbulence and little fluctuations in space and time.

3. Number of sources:                 one

4. Coordinates:          Follow solar orbital motion and 
                         solar rotation
                     ecliptic, i.e. +- 23 degrees declination
                     moving target !

    Time critical:  no

 5. Spatial scales:

      5.1. Angular resolution (arcsec):          better than  0.1"

      5.2. Range of spatial scales/FOV (arcsec):                single field
           (optional: indicate whether single-field, small mosaic, 
            wide-field mosaic...)

      5.3. Single dish total power data: yes/no                    yes
      5.4. ACA:                                             if available

      5.5. Subarrays:                                             no


   6. Frequencies:

      6.1. Receiver band: Band 3, 6, 7, or 9                       3

      6.2. Lines and Frequencies (GHz):    continuum, two frequencies
            =

      6.3. Spectral resolution (km/s):       none

      6.4. Bandwidth or spectral coverage (km/s or GHz):   10 GHz


   7. Continuum flux density:                     10^6 Jy

      7.1. Typical value (Jy):
           (take average value of set of objects)         10^6 Jy


      7.2. Required continuum rms (Jy or K):                   100 Jy

      7.3. Dynamic range within image:                            10 db


     9. Polarization:  yes/no  (optional)                            no


   10. Integration time for each observing mode/receiver setting (hr):  
          1 second

   11. Total integration time for program (hr):                   10 hr

   12. Comments on observing strategy:      
   
  Start with short observing periods to test feasibility

********************************************************************

Review Chris Wilson:
--------------------------------------------------
Review v2.0:
 
3.1.1 was unchanged.  DRSP1.1 says review by Chris Wilson but no
    text. I really have nothing to add; Chris' review is crystalline.