Gain Notes for Revolution 1454
	




	Gain Notes for Revolution 1454

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.

NB!!!!! This revolution has 3 separate switch-ons, each of which requires a settling
period during which the energy calibration is only partially understood. This means that
data taken within a couple of hours of a switch on (immediately after radiation belt
exit, or manually commanded after ground station outage), will be unsuitable for 
energy sensitive applications.
 

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.

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: 

The Xe line analysis performed using the IC table shows acceptable gain
correction with all science windows with a Xe peak fit that has a realistic
fitted width, having a Xe level within 3-4% of the ideal. Very bad periods with
poor Xe determination cluster around the switch ons, and cannot be improved with
offline corretions.
As usual, it is recommended that users avoid the first few science 
windows for energy-sensitive applications (automatically removed by OSA 10.0).


Calibration source number 4 (purple/orange) is no longer
used for calibration purposes since an anode strip directly under the source
has broken and no useable signal comes from this area of the detector any
longer.

CAO 29/9/2014

JEM-X2: 

The Xe line analysis performed using the IC table shows excellent gain
correction with all science windows (taken 1 at a time) having a Xe level 
within 2% of the ideal, except for the first few SCWs and the very last SCW. 
As usual, it is recommended that users avoid the first few science 
windows for energy-sensitive applications (automatically removed by OSA 10.0).


As with JEM-X1, source 4 is no longer used for energy correction purposes due
to a broken anode strip

CAO 18/9/2014