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: http://xmm.vilspa.esa.es/sas/7.0.0/doc/epreject/node8.html
Дата изменения: Wed Jun 28 23:40:15 2006 Дата индексирования: Sat Dec 22 09:38:54 2007 Кодировка: Поисковые слова: annular solar eclipse |
In this version of epreject only the boxcar method for screening the soft flares has been implemented. This method has been proven to be very robust. In order to perform the soft flare event selection the program generates a lightcurve in 0.1 sec bins in the specified PHA range using the rawevents obtained from the epframes procedure. This lightcurve is then smoothed with a boxcar function. The width of the boxcar can be given as parameter by the user. This smoothed lightcurve is then used to help perform the soft flare event selection. Here each photon is checked to see whether it has a PHA value in the user given PHA range (default: 40-50 ADU) and the lightcurve is above the user given softflarethreshold1 (this absolute count per 0.1 sec bin value has to be optimised for each observation as the contribution of the source photons in the given PHA range varies a lot from observation to observation). The criteria above keep events above the upper PHA threshhold during the softflare events as good events. A flag column labeled ''Flare`` is added to the rawevents file. A ''1`` in the column denotes that is has been flagged as a soft flare event. This column can the be used to screen the data.