SUMER study: Long rasters at 790, 786 Angstroem

date, time: 19.Feb.96, 23:07 UT - 20.Feb.96, 09:15 UT
field of view: 135 arcsec E - 135 arcsec W, 60 arcsec N - 44 arcsec S
slit: 1.0 arcsec x 120 arcsec, centered (number 4)
raster step size: 0.75 arcsec (2 elementary steps)
exposure time: 10 seconds
telemetry: 10(scans)*2(lines)*360 images of 50 spectral x 120 spatial pixels (format 10)
compression: bytescale-min-max (method 1)
wavelengths:
790.20 Å on reference pixel 280 of Detector A
786.50 Å on reference pixel 456 of Detector A
rotation compensation: standard
binning: no spectral, no spatial
on-board flat field correction: no

Remarks: 10 scans were executed in alternating directions. Only the first scan is shown (for both lines). The whole study in O IV 790.2 can be downloaded as an animation (see below). The rest of the study in S V 786.5 is not presented here; the line is weaker and the results noisier.

Spectral windows

Average detector image, average profile.

O IV 790.2 (170 000 K)

Continuum intensity, line intensity,
line shift, line width.

S V 786.5 (170 000 K)

Continuum intensity, line intensity,
line shift, line width.

Animation of O IV scans

When the scans are viewed consecutively, the dynamic of the transition region becomes visible. Please note that each scan takes approximately one hour, so the whole animation covers 10 hours.

The first animation shows the complete scans. Download the IDL/XDR restore file O4MOVIE1_XDR.RST (2150 KB) and the small IDL routine O4MOVIE1.PRO and then start the animation by entering
IDL> .run o4movie1

The second animation shows a subset of the scans, corrected for solar rotation and the effect of scanning in alternate directions. Download the IDL/XDR restore file O4MOVIE2_XDR.RST (1500 KB) and the small IDL routine O4MOVIE2.PRO and then start the animation by entering
IDL> .run o4movie2

Both IDL routines give the choice to view an endless animation of either continuum intensity, line intensity, line shift or line width.

Temporal behavior

While the fine structure changes from one scan to the next, the underlying network structure appears to be quite stable (and similar in continuum and O IV line) over the ten hours. This is demonstrated by averaging the corrected subsets mentioned above. If you click on the images you will find the time series of continuum and O IV line, respectively.

10-h-average of continuum, O IV line

IED, 07.Jun.00