Determining the Absolute Astrometric Error in Chandra Source Catalog Positions
Instrumentation and Methods for Astrophysics
2010-12-24 v1 High Energy Astrophysical Phenomena
Abstract
Although relative errors can readily be calculated, the absolute astrometric accuracy of the source positions in the Chandra Source Catalog (CSC), Version 1.0, is a priori unknown. However, the cross-match with stellar objects from the Sloan Digital Sky Survey (SDSS) offers the opportunity to compare the apparent separations of the cross-matched pairs with the formally calculated errors. The analysis of these data allowed us to derive a value of 0.16" for the residual absolute astrometric error in CSC positions. This error will be added to the published position errors in the CSC from now on, starting with CSC, Version 1.1.
Cite
@article{arxiv.1011.5401,
title = {Determining the Absolute Astrometric Error in Chandra Source Catalog Positions},
author = {Arnold H. Rots and Tamas Budavari},
journal= {arXiv preprint arXiv:1011.5401},
year = {2010}
}
Comments
18 pages, 6 figures, accepted for publication in ApJSuppl