Gain Notes for Revolution 1188

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 was an unusual revolution in that there was a sudden drop in the Xe line
position about half way through the revolution which recovered well before the end. 
This drop, which didn't affect the calibration sources was seen in both units. Also,
the Molybdenum line disappeared in both units though the Cu/Si line did not. Usually
the Cu/Si line is the first to be disrupted by large temperature changes or uncorrectable
changes in the spatial gain of the microstrip plate. It is not clear why this is.
 

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 good gain
correction with all except a couple of misfitted outliers and 4 other
 science windows having a Xe level 
within 2-3% of the ideal. The four worst SCWs are still within about 4% of ideal.
As usual however, it is recommended that users
avoid the first few science windows for energy-sensitive applications.


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.

JEM-X2: Results coming soon.

CAO 10/07/2012

	Gain Notes for Revolution 1188
	

JEM-X2: 

The Xe line analysis performed using the IC table shows very good gain
correction with all 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 10/07/2012