SAS Thread - epic slew processing - XMM-Newton
How to process EPIC slew data
This thread explains how to process slew data taken with the EPIC-pn camera.
At the end of this thread a set of filtered event files and images will have been created. These represent contiguous sections of the slew.
SAS Tasks to be Used
It is assumed that a slew data file (SDF) has been unpacked into the current directory. The SDF may be obtained from the archive.
Last Reviewed: 25 MAY 2023, for SAS v21.0
Last Updated: 16 January 2017
- Set up your SAS environment (following the SAS Startup Thread)
- Create an EPIC-pn event list from the slew data file. The procedure for this is identical to the initial processing of a pointed observation (see How to reprocess ODFs to generate calibrated and concatenated EPIC event lists).
- Tell the SAS to use the Raw Attitude File (RAF) for the attitude reconstruction of the slew by:
- csh: setenv SAS_ATTITUDE RAF
- sh: export SAS_ATTITUDE=RAF
- Run eslewchain
This task does not need any parameters. It reads the EPIC-pn event list from the directory pointed to by the environment variable SAS_ODF and processes the whole slew (which can take several hours for a long slew) producing a set of output files.
The output files are given below where the band number b means:
- Attitude corrected images of name PobsidPNS003IMAGE_biii.ds Where, obsid is the 10-digit observation number, b is the energy band identifier and iii is the image sequence number in hexadecimal which typically increments from 000 to 04A or so.
- Exposure maps of name PobsidPNS003EXPMAPbiii.ds
- Filtered event files for each image section of name: PobsidPNS003PIEVLI0iii.ds
- Unfiltered images of name PobsidPNS003UNFDAT8iii.ds
Note that the images produced have a small overlap to avoid problems with sources located at the very edge of an image. Due to this, some sources will be found in two consecutive images.
- Optionally run eslewsearch to perform source searching on the produced slew images
This task has no input parameters.
It produces four output files:
- PobsidPNS003OMSRLIb000.FIT a source list for bands 6,7,8
- PobsidPNS003OMSSLI0000.FIT a combined source list