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The ROSAT HRI Point Spread Function

Peter Predehl·Almudena Prieto
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Abstract

A sample of the brightest point-like sources observed with the ROSAT-HRI were analysed to asses on the intrinsic shape of the ROSAT-HRI Point Spread Function (PSF). Almost all of the HRI observations collected during the ROSAT lifetime are found to be artificially broadened by factors up two ~2 due to residual errors in the ROSAT aspect solution. After correction by departing pointing positions, the width of the core of the PSF is found to be less than 5 arcsec (half energy width, HEW). On the basis of these results, an improved analytical representation of the ROSAT-HRI PSF is provided. However, for most of the new observations the source countrate is too weak to allow reliable recovering pf the ROSAT-HRI resolution. Therefore, a series of examples (data, correction, and theoretical PSF) are given in order to help the ROSAT user in determining whether "his/her source" is extended or not.

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Peter Predehl, Almudena Prieto. 2001-09-28. The ROSAT HRI Point Spread Function. https://arxiv.org/abs/astro-ph/0109542

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