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EIT observing details

As a backup possibility for the case, if the TRACE is not available, the EIT imaging measurements in the limited FOV with the highest possible frame cadence are proposed. The EIT is worser (backup) alternative of the TRACE measurements due to the decrease of the frame cadence, decrease of the practical spatial resolution and also due to loosing of the Ly bandpass.

FOV (HxV) : 2x4 32x32 sub-arrays (166.4'' x 332.8'')

Bandpasses : Fe IX-X 171 Å (1.3x10 K), He II 304 Å (8.0x10 K)

Compression : square root (roughly 1:2) and ADCT (1:5), frame volume decrease from 112 kb to

roughly 12kb

Telemetry : < 20 sec

Exposures : 171 Å : 12 sec, 304 Å : 52 sec

Dwell time : 8 sec (readout, CCD clearing)

Cadence : 171 Å : 20 sec, 304 Å : 9 min

Order : After each 27 Fe IX-X 171 Å frames acquired in a sequence (9 min) one He II 304 Å frame

should be inserted with the resulting cycle time of 10 minutes

Total time : up to app. 7 hours

Luis Sanchez Duarte
Thu Apr 22 10:19:16 EDT 1999