Gain Notes for Revolution 1790

This is one of the later revolutions in the mission where the calibration
sources have become so weak that for the best energy determination and
IC Gain History table is needed.

N.B.: This revolution was interrupted mulitple times due to limited ground station
coverage. Hence much of the data was taking during what were instrument settling
periods during which gain was changing rapidly and non-uniformly all over the
detector microstrip plates. Hence while the overall energy determination may appear
Very Good, there will be greater than usual variation in energy calibration 
across the detector, causing a loss of energy resolution during this revolution.
 
To get optimal results with this revolution it is necessary to use the IC gain history.
See notes in revolutions prior to revolution 1433 to find out how to do this
if you don't already know.

All offline gain/energy corrections (including the IC tables) are based on the
two Fe calibration sources in JEM-X1, for both units.

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 (but for 2 misfits, Xe position within 2-3% of ideal)


JEM-X2 rating: Very good (also with a couple of outliers)

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

CAO 10/03/2017