Gain Notes for Revolution 1242 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 affected by a solar flare on 15th December 2012, which strongly suppressed the gain on both JEM-X instruments. While data is fine for energy-independent processing like imaging, light-curves and spectra will be affected by the many events lost to the low level rejection during the flare. It is suggested that users avoid this period when doing spectral or lightcurve analysis. The flare period between IJD=4731.8 and 4732.6 has been declared a BAD_RESPONSE BTI (Bad Time Interval). 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="/". 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 excellent gain correction outside the period affected by the solar flare. During the flare period the gain correction is acceptable, but many events will have been lost onboard to the low level rejection and so spectra will still be very poor, despite the IC table corrections on event energy values. This period is a BAD_RESPONSE BTI 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 17/12/2012 Gain Notes for Revolution 1242 JEM-X2: The Xe line analysis performed using the IC table shows good gain correction outside the BTI period with all except the very first science windows having a Xe level within about 3% of the ideal. As usual however, it is recommended that users avoid the first few science windows for energy-sensitive applications. CAO 18/12/2012