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Paper: QPTOOLS: Tools for Creating and Manipulating IRAF/QPOE data
Volume: 61, Astronomical Data Analysis Software and Systems III
Page: 363
Authors: Conroy, M. A.
Abstract: The QPOE data format was developed by IRAF to support photon event list data. The filtering mechanisms that IRAF provides with this data structure make it a very powerful tool for data analysis. One of the key features of this data format is the automatic conversion from EVENT-list format to IMAGE data format. However, it is often desirable to view and manipulate the QPOE file in tabular form. We are developing several tasks that allow users to generate QPOE files of their own description and to modify existing data files: QPCALC -- perform arithmetic operations on one or more event-attributes QPLINTRAN -- apply linear transformations to the special 'x' and 'y' data columns that are used to generate the IMAGE data. QPAPPEND -- combine 2 or more QPOE files. QPCREATE -- generate a QPOE file from an input ASCII list. Some applications of these tasks to ROSAT and Einstein data analysis will be discussed. For instance, errors in aspect can be corrected by applying shifts and/or rotations to the data columns for 'x' and 'y'. Errors in the instrument energy calibration can be corrected by applying a new algorithm to the raw PHA value(s) in the file. Users can also create their own QPOE file by replacing columns in an existing file using simulation functions, or by importing ASCII lists of events.
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