XMM-Newton Data Analysis

XMM-Newton Data Center at MPE
Create a lightcurve of a point source from EPIC MOS data

input file: events.fits
output file: source_light.fits
instrument: EPIC PN, IMAGING mode

Define the regions you want to select for your point source and background region as described in the select region page
Make sure the starting and end times of the source and background light curves are the same. The best way to avoid any confusion is to set time ranges as given in the examples below.
In principle, there are two ways to extract a spectrum using the XMM-SAS tools:

evselect or
xmmselect.

1. evselect:
evselect table=events.fits withrateset=true \
expression="circle(25200,24000,1400,X,Y) .and. FLAG .eq. 0" \
maketimecolumn=true timebinsize=100 rateset=lightcurve.fits
Warning: in order to get a lightcurve with columns TIME and COUNTS, you have to set maketimecolumn=true. Otherwise evselect only creates an output file that contains a column COUNTS. In xmmselect it is set automatically.

2. xmmselect
xmmselect table=events.fits
This will start a Graphical User Interface:

xmmselect GUI Start window

In the xmmselect GUI start window click the circle (the second column) in the Column Selection part at the column TIME
Select the region for the source photons : circle(25200,24000,1400,X,Y) in the Selection expression part.
Click on the OGIP Rate Curve button at the Product Selection part. This will open the evselect general window.

evselect general window

On the evselect general window usually you do not have to change anything.
Click on the OGIP Rate curve button in the Product Selection.

evselect lightcurve selection window

In the evselect rate window choose a name for your output light curve, e.g. lightcurve.fits
set the timebinsize to the binsize you want, e.g. 100 (seconds).
In XMMSELECT, the switch maketimecolumn is default set to true.
Click on Run in the lower row.

Lightcurve display window

xmmselect will automatically start a display window that will plot the light curve.