Gain Notes for Revolution 856
	
JEM-X1: No scientific data or gain history for this unit.


JEM-X2: This was the first revolution since JEM-X2 was switched on for
full-time use, and unfortunately the unit was switched on with the wrong
energy binning table loaded. This means that the energy correction is
significantly lower than it should be and an IC gain history table produced
offline and edited to correct this fault is needed to get the best energy
determination for this revolution. The first part of this revolution was thus
declared a Bad Time Interval in the period IJD = 3576.8 to 3577.2


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 gain history table, gives an energy correction to within 1-2% of
the ideal. As always however, it is best to avoid the first few science windows
for any application requiring very good energy determination.


CAO 30/11/2009