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 rotate – the telescope position angle coortype – the output PSF coordinate xsize, ysize – the size of the PSF

Coordinate complexity

position angle: anti-clockwise on xy coordinate

xy(output of calview/cal)

Invert X

detx/detyShrink 22 times

rawx/rawy

whole camera

Individual CCD

Theta/phi(input of cal)

polar Cartesian

Image/PSF

Location oncamera

Rotate

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 using different coordinates from xmmselect.

Examples

Operating System dependency

MEDIUM

LevelLinux Solaris

OSX

PowerPC

OSX

i386

Linux 81 55 81

Solaris 39 104 0

OSX

PowerPC39 0 104

OSX

i38639 0 0

MOS1 3000eV theta=500 phi=60MO

S2

10

00

eV

the

ta=

30

0 p

hi=

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 Viewerhttp://manaslu.star.le.ac.uk/epic8/xmm-viewer/

Thank you!