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psfgen The SAS Task. What is psfgen ?. A tool that has more flexibility on creating PSFs of the XMM instruments. Main parameters. instrument, ccdnr – select the camera & CCD level – PSF accuracy level energy – list of energy of interest theta, phi – PSF centre on the cameras
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What is psfgen? A tool that has more flexibility on creating PSFs of the XMM instruments.
Main parameters • instrument, ccdnr– select the camera & CCD • level – PSF accuracy level • energy – list of energy of interest • theta, phi – PSF centre on the cameras • rotate – the telescope position angle • coortype – the output PSF coordinate • xsize, ysize – the size of the PSF
Coordinate complexity Theta/phi (input of cal) Location on camera polar Cartesian xy (output of calview/cal) whole camera Invert X Rotate Image/PSF detx/dety Shrink 22 times rawx/rawy Individual CCD position angle: anti-clockwise on xy coordinate
image parameter to rescue psfgen image=an_example_image.fits level=ELLBETA (Note: the centre of the source should be located at the region centre.)
Examples – 0470_0109480101_002 MOS2 xy detx/dety rawx/rawy Select the source usingdifferent coordinates from xmmselect.
Operating System dependency MOS1 3000eV theta=500 phi=60 MOS2 1000eV theta=300 phi=45 (Note: the numbers in the table are the counts of the pixels that differ between two OS PSFs. The total pixel number of a PSF is about 40K.)
Operating System dependency • Not the precision error. • Relative error from few percent to few hundreds percent. • Extreme example 1 – 0.001029 vs 0.014383 (10 times difference) • Extreme example 2 – 3.98332 vs 4.98503 (1.0017 difference)
EPIC MOS Plotting Viewer http://manaslu.star.le.ac.uk/epic8/xmm-viewer/