Create the Ancillary Region File (ARF)

The Ancillary Response File (ARF) can be used with the RMF to fit spectral models to the observed spectrum. It contains a table of area values for several different energy ranges, having taken into account the calibration information and the state of the data.

To make the ARF using the GUI:

1)

Call arfgen in the Available Tools panel.

2)

Enter the name of the input spectrum, in this case, mos1_source_pi.fits, the input response set, mos1_rmf.fits, and the output ancillary response set, in this case, mos1_arf.fits.

3)

Confirm that ``Correct for bad pixels in source box'' is set to ``yes'', and next to ``File containing bad pixel extensions'', enter the name of the event file from which the spectrum was extracted, in this case, mos1_filt_time.fits. Next to ``Get ebins from response set'', click ``yes''.

4)

Click on ``Run''.

To make the ARF using the Command Window, type:

arfgen arfset=mos1_arf.fits spectrumset=mos1_source_pi.fits withrmfset=yes
$$ rmfset=mos1_rmf.fits badpixlocation=mos1_filt_time.fits

where

arfset - output ARF file name
spectrumset - input spectrum file name
withrmfset - flag to use the RMF
rmfset - RMF file created by rmfgen
withbadpixcorr - flag to include the bad pixel correction
badpixlocation - file containing the bad pixel information; should be set to the event
$$ file from which the spectrum was extracted.