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arXiv · 1102.5218

Astrometry and photometry with HST WFC3. II. Improved geometric-distortion corrections for 10 filters of the UVIS channel

A. Bellini·J. Anderson·L. R. Bedin
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Abstract

We present an improved geometric-distortion solution for the Hubble Space Telescope UVIS channel of Wide Field Camera 3 for ten broad-band filters. The solution is made up of three parts: (1) a 3rd-order polynomial to deal with the general optical distortion, (2) a table of residuals that accounts for both chip-related anomalies and fine-structure introduced by the filter, and (3) a linear transformation to put the two chips into a convenient master frame. The final correction is better than 0.008 pixel (~0.3 mas) in each coordinate. We provide the solution in two different forms: a FORTRAN subroutine and a set of fits files, one for each filter/chip/coordinate.

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A. Bellini, J. Anderson, L. R. Bedin. 2011-02-25. Astrometry and photometry with HST WFC3. II. Improved geometric-distortion corrections for 10 filters of the UVIS channel. https://doi.org/10.1086/659878

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