Документ взят из кэша поисковой машины. Адрес оригинального документа : http://xmm.vilspa.esa.es/sas/6.5.0/doc/esensmap/node3.html
Дата изменения: Tue Aug 16 03:12:43 2005
Дата индексирования: Sat Dec 22 08:56:36 2007
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Поисковые слова: annular solar eclipse

XMM-Newton Science Analysis System


esensmap (esensmap-3.11) [xmmsas_20050815_1803-6.5.0]

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Description

This task creates a sensitivity map giving point source detection upper limits (vignetting corrected source count rate corresponding to the likelihood of detection as specified in the parameter file) for each image pixel. The task may either be called for individual energy bands or combinations of energy bands and instruments. The upper limits are calculated by assuming Poissonian count statistics in each 3 $\times$ 3 pixel detection cell, using the exposure and background values read from the input images. It is assumed that 30 upper limit calculation is meant as a reference point for a more detailed assessment of the sensitivity of the detection process to be determined through Monte Carlo simulations.

In the case of multiple input energy bands the upper limits are expressed in units of counts per seconds for the combined band (i.e. they refer to the detection sensitivity which would be acchieved by adding up the photons observed in the individual bands). Pixels outside of the detection mask used by the eboxdetect detection task as well as pixels with zero exposure time are assigned a sensitivity value of -1.0. This also holds for pixels where - due to a failure of the esplinemap backgound task - zero or negative values occure in the input background maps.