Gain Notes for Revolution 893
	
JEM-X1: No scientific data or gain history for this unit.


JEM-X2: A complete revolution of SCO X-1 observations in which the powerful
celestial signal overwhelms the weak calibration signal causing many
strange points in the automatically generated gain history table.

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.

Using the IC gain history table the energy correction for this revolution is
within about 2% of the ideal value for all science windows, so all of the
data should be useable for all purposes including sensitive spectral
analyses.


CAO 08/02/2010