Gain Notes for Revolution 2629

This is one of the later revolutions in the mission where the calibration
sources have become so weak that for the best energy determination an
IC Gain History table is needed. These gain history tables are found
automatically by OSA, or can be downloaded from the DTU FTP site.
 
All offline gain/energy corrections (including the IC tables) are based on the
two Fe calibration sources in JEM-X1, for both units, then corrected iteratively
using the instrument background lines (Xe, backed up by Cu and Mo).

Latest OSA software (version 10 and higher) automatically cuts out the first
Science windows of data from each revolution to ensure that people do not use data
from the instrument-settling period. This process can be overruled, but only by
experienced users.
	
JEM-X1 rating: Very good (within  2-3% of ideal, except for settling zone
		and 3 misfitted outliers with unphysical widths)

JEM-X2 rating:  Acceptable (within  5-6% of ideal, except for settling zone, and
		some weak misfitted outliers). It is not clear why JEM-X2 has
	such poor gain determination compared to JEM-X1, but it probably has
	to do with the temperature in this instrument deviating somewhat from
	the temperature measured in the electronics box. Now that temperature
	dependancy of the gain is stronger than it was at the beginning of
	the mission, this descrepancy can have significant effects on the
	gain determination. 

The JEM-X2 corrections are based on the JEM-X1 Fe calibration sources, since
all the Cd sources are now too weak to use.

CAO 15/05/2023