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GHRS Instrument Science Report 047

GHRS Instrument Science Report 047

"4462: A follow-up on GHRS ISR 044" 04/93 

Lisa E. Walter and Stephen J. Hulbert

Abstract excerpted from the report:

Proposal 4462, GHRS SSA Offset Verification Test was run for the second time
on 22 Jan 1993. New SSA/LSA Ratios were calculated and proved to be nominal.
Also a new offset was calculated and determined to be small enough to not
warrant an update to the PDB. We refer you to GHRS ISR 044 for a more
thorough explanation of the test.

The GHRS SSA Offset Verification Test performs a standard target acquisition
(LSA), offsets to the SSA, and then uses POS TARGs to trace out a diamond-
shaped spiral pattern on the sky in order to explicitly determine the residual
pointing error after the blind offset to the SSA. Flux measurements are taken
in the LSA both before and after the diamond spiral to verify that the point-
ing is consistent.