Notes on analyzing data using XSELECT


XSELECT is a program to examine input event files, filter these to include events of interest then create data products to further analysis. It performs many of these functions by running individual tasks from the FTOOLS suite. It also uses tasks from CIAO and SAS.

The aim of XSELECT is to make standard data product creation simple and uniform across many missions. Currently XSELECT supports ASCA, BBXRT, Chandra, Einstein, EXOSAT, Integral, ROSAT, BeppoSAX, Spectrum-RG, Suzaku, Swift, RXTE, and XMM-Newton. New missions can be added simply by editing an external ascii file, the MDB.

Versions 2.2 and later include the ability to automatically generate responses for extracted spectra. The save spectrum has an argument response which if set to yes will cause the rmf and arf to be generated. If the mission software supports creation of an extended source arf then this can be generated by instead setting response=extend. Response generation is available for ASCA, Chandra ACIS, Einstein IPC, ROSAT, Suzaku, XMM-Newton EPIC, and RXTE PCA.

Chandra and XMM-Newton users should note that the select events command does not at present update the Data Model Subspace keywords so should be avoided if CIAO or SAS routines will be run on any products generated after the selection. Using filter followed by extract (alias bin) does correctly update the relevant keywords so is preferred.

Setting up (local notes for GSFC)

XSELECT is part of HEAsoft. To start up the local developement version use
source /software/lheasoft/develop/ftools.csh

If you are working on Chandra data then you will probably need to set up CIAO using
source /usr1/local/Chandra/ciao/bin/ciao.csh

If you are working on XMM-Newton data then you will probably need to set up SAS using
source startxmm.csh
where startxmm.csh is a handy little script you can download and run.

I suggest including aliases to these commands in your .cshrc (I use go_ftools, go_chandra, and go_xmm, respectively).

Notes for individual missions

A service of the Laboratory for High Energy Astrophysics (LHEA) at NASA's GSFC
Responsible NASA Official: Phil Newman
Curator: Keith Arnaud

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This file was last modified on Wednesday, 14-Mar-2012 17:47:30 EDT