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Paper: Temporal Data Screening in PROS
Volume: 61, Astronomical Data Analysis Software and Systems III
Page: 367
Authors: Deponte, J.; Conroy, M.
Abstract: Filtering and selection of photons is often a user's first step in the scientific analysis of astronomical data. For instance, satellite based X-ray observations are acquired under a set of constantly changing conditions. The position of the target on the detector is not constant, and observing conditions such as background rate, aspect quality, and bright object contamination change as a function of satellite position and telemetry quality. These conditions are recorded and saved in the data files provided to the observer along with the photon data that are stored with spatial, temporal and energy band attributes. In the PROS/IRAF environment event data are stored as QPOE files where there is IRAF support for filtering on each of the data attributes. Ancillary data are stored as TABLE files and supported by a package of tools that allows the user to view and manipulate the data. We present several tasks that have been developed to enhance the filtering capabilities of IRAF by allowing users to build temporal filters based on screens applied to TABLE files. The Temporal data intervals are then used to screen photons in the QPOE file, giving the user the opportunity to reject or recover photons, using the tasks: hkfilter -- generates a QPOE time filter from an input housekeeping filter tabfilter -- an interactive graphical data quality selection and display task. Specific examples applicable to ROSAT data will be discussed.
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