Gain Notes for Revolution 1389

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 is strongly affected by solar activity, causing the instruments to be
shut off for much of the revolution. For JEM-X1 it was not possible to do a good gain
correction because of non-linear gain suppression which caused the Xe line to be far
too high (30.7 keV) while the Cu line appears far too low (7.3 keV) for this reason 
a Bad Time Interval (BTI) has been declared for JEM-X for the entire revolution
BIT = 5170.5 to 5173.5 IJD. This is a Bad Response BTI, and it can be overruled by
a user GTI, but should only be done by expert users. This data should never be used for
energy-sensitive or spectral purposes.


To get optimal results with this revolution it is necessary to use the IC gain history
table that has been created offline at DNSC, instead of the gain history table
created automatically by OSA. If you have the newest package of IC files from ISDC
and these are correctly installed, OSA will find the IC gain history table automatically
and you don't need to do anything else. The updated ISDC Instrument Characteristics
can be downloaded from
http://www.isdc.unige.ch/integral/download/osa_sw



However, if you don't have the IC gain table
package from ISDC you can download the table from the gain history archive by
anonymous ftp through the link provided. Download the table to some suitable
subdirectory for your analysis, then set the hidden OSA parameter gainHist:
gainHist="<my subdirectory>/<IC filename>". These files are used instead of the
automatically generated gain history tables wherever there has been an unusual or
non-linear behaviour of the detector gain.

	
JEM-X1: 

The Xe line analysis performed using the IC table shows apalling gain
correction for which a BTI (5170.5 to 5173.5 IJD) has been declared. Do not use
this data for scientific purposes unless you really know what you're doing. Or contact
the instrument team: oxborrow "at"space.dtu.dk.



JEM-X2: 

The Xe line analysis performed using the IC table shows very gain
correction with all except the very first and last science windows having a Xe level 
within 2-3% of the ideal. As usual however, it is recommended that users
avoid the first few science windows for energy-sensitive applications.

CAO 24/03/2014