The SWIFT BAT Software Guide Version 6.3 30 ... - HEASARC - Nasa

Appendix A
BAT Data Formats
A.1 Introduction
This Appendix provides a detailed account of the formats of BAT data. A discussion of file naming
provided; followed by descriptions of BAT science products, including event, survey and rate data;
and finishing with descriptions of housekeeping and trend data products.
A.2 File Naming Overview
All BAT data products are FITS files. The Level 0 and 1 products are either FITS tables or null
files (header only). All files are named according to one of the following conventions (“sw” is Swift
and “b” is BAT):
sw[Observation ID][Segment Number]b[code].[suffix]
or
sw[Time stamp]b[code].[suffix]
For example, an event file for Observation ID 00074651, segment 002, would have a name
sw00074651002bevtstouf.evt, where the code for event files is “evtstouf” and the suffix is “evt.”
Similarly, a long trigger criteria trend file from MET 101809021 would have a name sw0101809021btblt.fits,
where the code is “tblt” and suffix “fits.”
A.3 Event Files
These are time-ordered FITS tables, with each row corresponding to a single event. A fully processed
event file will contain no duplicated events. Event files can be distinguished by the unique
filename suffix “evt,” and various codes refer to different types of events and different stages in
processing.
The columns in a fully processed event file are (EXTNAME = ‘EVENTS’):
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