Gain Notes for Revolution 834
	
JEM-X1: This is a revolution with unexpectedly high gain, which unfortunately
introduces non-linearities into the gain correction. To get correct energy
calibration of the science data from this revolution you MUST USE an IC
gain history table that has been corrected offline for these gain changes.
This table can either be downloaded from the Gain History Archive page which
contains these notes, or as a complete package of gain history tables from
ISDC. The OSA software will automatically locate this offline gain history
table and use it instead of the table generated online by OSA. When the
correct IC gain history table is used for correction of this data, the
energy calibration is correct to within +- 2-3% of the ideal.
Without the IC gain history table energy correction is consistently
about 3-4% too low.

However, as for all revolutions, the first few science windows should be
avoided in any analysis requiring very good gain determination. Results shown
here use OSA8.0 software and so include temperature variation in the
smoothed gain model. 

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: No scientific data or gain history data for this unit.



CAO 4/10/2009

	Gain Notes for Revolution 834
	
JEM-X1: A quite normal revolution with fine gain fitting. All the data from 
this revolution should be useable. The Xe analysis confirms that the energy
determination for this revolution is okay, within about 3% of the ideal. 
However, as for all revolutions, the first few science windows should be
avoided in any analysis requiring very good gain determination. Results shown
here use OSA8.0 software and so include temperature variation in the
smoothed gain model. 

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. 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.


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: No scientific data or gain history data for this unit.

CAO 4/10/2009