Title:                   JOP176 SHORT-TIMESCALE CORONAL HOLE EVOLUTION

Author:                  Barbara Bromage (bjibromage@uclan.ac.uk)

Received: 25 May 2004

Ideal conditions:
  large, low-latitude coronal hole crossing the meridian.
Compromise conditions:
  coronal hole boundary at lowest latitude available and as near to
  the meridian as possible.

Observe:
        for 3-5 days, twice per day, CDS study UCLAN_N4 (4'x4') run
        three times consecutively on a section of the boundary,
        allowing for rotation; the eastern boundary is preferred
        initially.

        Time taken: 3-5 x 2 x 3 = 18-30 hours (approx.)
        Run UCLAN_N2 (3 repeats) once during this period, ideally
        near the meridian, centred on the same boundary region.
        Time taken: 4hrs (approx.)

        EIT as well as synoptic observations, take EIT304 images about
        once per hour, to include the region of the CDS observations,
        not necessarily full-disc.

        MDI synoptic 96-minute full disc magnetograms;
        try to coordinate CDS obs with these (i.e. maximise the number
        of simultaneous observations). If MDI has High Rate telemetry,
        then produce full disc mags and dopplergrams at 1-minute
        cadence if possible.

        SUMER (if available) look for flows in the boundary region
        using transition region and low coronal lines; maybe network
        observations too?

AIMS:
        Observe the network and boundary of a coronal hole to see what
        the relationship is over time.

        Measure quasi-instantaneous rotation rate of the coronal hole
        and compare  this with the overall rotation rate over one or
        more rotations.

        Measure the temperature and density in the boundary region and
        look for flows in relation to changes in the boundary.


Total observing time (approx):

        Over 3 days - 22 hours.
             5 days - 34 hours.