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HEXTE Cluster Position


HEXTE data files contain data from only one of the two clusters but are not split further into on-source and off-source files. To create separate data files for further processing, you can use the ftool fselect. How exactly this is done depends on whether your HEXTE data are in science array or science event format. In both cases, fselect operates on the ClstrPosition column, but the selection criteria differ.

For HEXTE science array data, the values of ClstrPosition corresponding to the on-source position are 0 and 3 for 1.5-degree and 3-degree rocking, respectively. This means that to create a file containing only on-source data, the following fselect criterion should be used:

ClstrPosition.eq.0.or.ClstrPosition.eq.3
And to create the off-source file, use:
ClstrPosition.ne.0.and.ClstrPosition.ne.3
For HEXTE science event data, the values of ClstrPosition corresponding to the on-source position are 1 (or 65) and 8 (or 72) for 1.5-degree and 3-degree rocking, respectively. This means that to create a file containing only on-source data, the following fselect criterion should be used:
ClstrPosition.eq.1.or.ClstrPosition.eq.65.or.ClstrPosition.eq.65.or.
  ClstrPosition.eq.72
And to create the off-source file, use:
ClstrPosition.ne.1.and.ClstrPosition.ne.65.and.ClstrPosition.ne.65.and.
  ClstrPosition.ne.72

For example, to create the file event_off.fits containing only off-source data from the science event file FS50_3eb70b0-3eb8950:

kaah[16]% fselect
Name of FITS file and [ext#][] FS50_3eb70b0-3eb8950
Name of output FITS file[] event_0_off.fits
Selection Expression[] ClstrPosition.eq.1.or.ClstrPosition.eq.65.or.ClstrPosition.eq.65.or.
  ClstrPosition.eq.72


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The ABC of XTE is written and maintained by the RXTE GOF. Please email xtehelp@athena.gsfc.nasa.gov if you have any questions or comments. This particular page was last modified on Tuesday, 14-Sep-1999 13:45:41 EDT.