Physical Sciences and Mathematics Commons^™

New Insight On Galaxy Structure From Galphat I. Motivation, Methodology, And Benchmarks For Sersic Models, Ilsang Yoon, Martin D. Weinberg

Astronomy Department Faculty Publication Series

We introduce a new galaxy image decomposition tool, GALPHAT (GALaxy PHotometric ATtributes), to provide full posterior probability distributions and reliable confidence intervals for all model parameters. GALPHAT is designed to yield a high speed and accurate likelihood computation, using grid interpolation and Fourier rotation. We benchmark this approach using an ensemble of simulated Sersic model galaxies over a wide range of observational conditions: the signal-to-noise ratio S/N, the ratio of galaxy size to the PSF and the image size, and errors in the assumed PSF; and a range of structural parameters: the half-light radius $r_e$ and the Sersic index $n$. …