Hinode QS and CH Boundaries

Quiet Sun studies

Science Goal:

The general aim of EIS quiet Sun studies is to correlate the coronal emission seen
with EIS with the magnetic topology inferred from the FPP data. EIS will uniquely
determine temperature, density, and the velocity field of the corona. Additional
aims are to provide higher cadence studies for the evolution of dynamic network
events such as explosive events and blinkers.

Four programs are identified below to carry out the quiet Sun studies. We also list as
a fifth program a spectral atlas, although this is likely to be part of the EIS
synoptic/calibration program anyway. All of these programs can be applied to coronal holes
and coronal hole boundaries with no changes.

For each study the following parameters are fixed:

    Wavelength windows: 24 pixels (except slot studies)
    Y=512" (along slit)
Two generic quiet Sun line lists are used for the quiet Sun programs, and these are given below.

Line Lists

List QS1
Fe X184.54
Fe XII186.88
Fe XI188.23
Fe XII195.12
Fe XII196.65
Fe XIII202.02
He II256.32
Si VII275.35
Fe XIV264.79
Fe XV284.16
Ca XVII192.82
Fe XXIV192.03
S X264.23
Fe XIII203.83
Fe VIII185.21
Fe XVI262.98
List QS2
He II256.32
Fe XII195.12
Fe XV284.16


Program 1

Alternate between slot and raster (1 of each) studies for several hours. The raster is
used for detailed diagnostics of an area of quiet Sun covering 2 supergranule cells. The
slot raster provides a quick overview of the quiet Sun region in 3 key lines.

  1. Raster 1
  2. Slit: 40"
  3. X=80"; 40" steps
  4. Exposure time: 50 sec
  5. Duration: 2mins
  6. Line list: QS2
  1. Raster 2
  2. Slit: 1"
  3. X=80", 1" steps
  4. Exposure time: 50sec
  5. Duration: 1hr 7mins
  6. Line list: QS1
Alternate rasters to fill the available time slot.

Program 2

This program is used to follow the changing morphology of the quiet Sun at high cadence.

  1. Slit: 40"
  2. X=40" (no raster)
  3. Exposure time: 50secs
  4. Duration: repeat at one location to fill available time slot
  5. Line list: QS2 (see above)

Program 3

Use EIS in sit-and-stare mode with the 1" slit in order to generate detailed, high cadence
spectra at a fixed location in the quiet Sun. Occasional 40" slot images are used for context.

  1. Raster 1
  2. Slit: 40"
  3. X=40" (no raster)
  4. Exposure time: 50 secs
  5. Duration: a single exposure
  6. Line list: QS2 (see above)
  7. Raster 2
  8. Slit: 1"
  9. X=1" (no raster)
  10. Exposure time: 50 secs
  11. Duration: repeat for between 1 and 3 hours (preferably 3) at one location
  12. Line list: QS1 (see above)
Alternate these rasters to fill available time slot.

Program 4

Similar to Program 1, but a smaller spectral raster is used to provide higher cadence
observations of a particular network feature (e.g. bright point, explosive event).

  1. Raster 1
  2. Slit: 40"
  3. X=80"; 2" steps
  4. Exposure time: 50 sec
  5. Duration: 2mins
  6. Line list: QS2
  7. Raster 2
  8. Slit: 2"
  9. X=10"; 2" steps
  10. Exposure time: 15 sec
  11. Duration: 75 sec
  12. Line list: QS1
Alternate these rasters to fill available time slot.

Program 5

Obtain spectral atlas of quiet Sun for detailed spectral diagnostics, and also for
calibration/reference. As well as quiet Sun spectra of the solar disk, the atlas program
should also be run off both the east and west solar limbs.

  1. Slit: 1"
  2. X=10", 1" steps
  3. Exposure time: 50 sec
  4. Duration: 2 hours (depends on data rate)
  5. Wavelength windows: 2048 pixels (complete spectra in both channels)

Last Revised: Monday, 24-Jul-2006

Feedback and comments: webmaster

EIS partner logo