Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/sas/6.5.0/doc/rgsenergy/node3.html
Дата изменения: Tue Aug 16 05:44:49 2005
Дата индексирования: Sat Dec 22 10:11:26 2007
Кодировка:
Поисковые слова: massive stars

XMM-Newton Science Analysis System


rgsenergy (rgsenergy-2.0.2) [xmmsas_20050815_1803-6.5.0]

Meta Index / Home Page

Description

This task calibrates the telemetered RGS pixel energies. It operates on a CCD-specific raw event list created by task rgsframes and adds the PI column to the PIXELS table. The calibration consists of three corrective procedures performed in sequence: offset correction, gain correction, and CTI correction. The CAL Handbook describes each procedure in detail. The offset correction can use static calibration data from the CCF (one value per CCD and node by each RGS), but also dynamic offset data derived from the diagnostic images can be used for subtraction. There are two methods available:

• Using averaged diagnostic images derived from three consecutive orbits, including the one corresponding to the data (parameter withdiagoffset). In this case the subtraction is performed pixel by pixel. This is the method considered as most accurate, due to the offset modulations observed with time within a CCD and node.
• Using any diagnostic data for derivation of one value per CCD and node (parameter withoffset).

The method used for offset correction is flagged in the keyword "OFFSCORR" in each EXPOSURE extension of the events file (either as "CCDNODE" or "PIX2PIX", corresponding to the one value or pixel by pixel subtraction, respectively).

For diagnostic purposes the gain and CTI corrections can be disabled independently (parameters withgain and withcti).

Throughout this document a marks items that do not apply to HTR mode data and a marks items that apply only to HTR mode data.