XMM-Newton Data Analysis

Developped for XMMSAS version 5.3.3. but should also work for more recent versions.
This page describes the XMMSAS task edetect_chain that performs a source detection on EPIC MOS and PN data. This meta-task combine the following XMMSAS tasks:

eexpmap for the creation of EPIC exposure maps
emask to create a mask image used for the source searching
eboxdetect(in local detection mode) creates an output source list for the next task:
esplinemap removes sources for the the input list and performs a spline fit to create a source-free background map.
eboxdetect (in map mode) creates output source list
emldetect EPIC maximum likelihood multi-source point spread function fitting
esensmap Creates an EPIC sensitivity map

edetect_chain allows to perform a source detection with up to 3 instruments (PN, MOS1, MOS2) in 5 different energy bands simultaneously. In contrast to older versions of the XMMSAS, edetect_chain deos create exposure maps. If exposure maps for the input image(s) do already exist, the calculation of exposure maps can be omitted by witheexpmap=no.
In our example we choose five input images of a MOS-1 observation in the energy bands (0.2-0.5, 0.5-2.0, 2.0-4.5, 4.5-7.5, and 7.5-12.0) created in a similar way as described on the color image page (This page explains it for an EPIC PN image, but can be used in the same way from EPIC MOS data).
     edetect_chain attitudeset=atthk.dat\
                 eventsets=P0103660201M1S002MIEVLI0000.FIT \
                 imagesets='image_0200.fits image_0500.fits image_2000.fits
		 image_4500.fits image_7500.fits' \
		 pimin='200 500 2000 4500 7500' pimax='500 2000 4500 7500 12000' \
		 ecf='1.6050 1.9451 0.74699 0.26459 0.02878'
Where pimin and pimax define the min and max PI energy channels values for each input image, and ecf the energy to count rate conversion factors per image. The numbers of pimin, pimax, and ecf must be the same as the number of input images. The right values for the ecf can be found in Table 3 in the SSC-LUX-TN-0059 document. This lists all ecfs for PN and MOS for all filters. Please note: the default of the ecf is 1.0. If you do not set the ecf to the right value(s) this does not effect the source detection, however the fluxes you get in the source list tables (see below) will be incorrect.
The output will be:
Exposure maps: input_image_rootexp.input_image_extention
e.g. image_0200exp.fits
Mask images: input_image_rootmask.input_image_extention
e.g. image_0200mask.fits
Background images: input_image_rootbkg.input_image_extention
e.g. image_0200bkg.fits
Source maps: input_image_rootsmap.input_image_extention
e.g. image_0200smap.fits
Please note that these are only processed when the parameter eml_withsourcemap=true is set.
Sensitivity images: input_image_rootsen.input_image_extention e.g. image_0200sen.fits
three source lists, two from eboxdetect and one from emldetect:
       eboxlist_l.fits, eboxlist_m.fits, and emllist.fits
   
Those source lists contain information about the positions of the sources in frame pixel coordinates (which you can use to convert into sky pixel coordinates to extract photons as described Select region page), source counts, count rates, hardness ratios and the position given in equatorial coordinates (given in degrees), plus some additional information. Hardness ratios are only calculated, of course, when input images are given at different energies.