Calstis2: Cosmic Ray Rejection in the STIS Calibration Pipeline
نویسندگان
چکیده
We describe calstis2, the calstis calibration module which combines CRSPLIT and repeated exposures to produce a single, cosmic ray rejected image. Cosmic ray rejection in the STIS pipeline employs a noise model and parameterized rejection criteria to identify and exclude discrepant values in forming the output image. The calstis pipeline is able to perform this cosmic ray rejection because the individually commanded exposures are associated together into a single dataset by TRANS and generic conversion. The functionality of calstis2 is also available as a host-level application and as a task in STSDAS to allow users to re-perform the cosmic ray rejection outside the pipeline with different input parameters. This document updates and supersedes STIS ISR 96-18, and describes the functionality that was implemented for calstis V1.7.
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