Measuring bar strength using Fourier analysis of galaxy images
1 DEIM, Campus Sescelades, Avd. dels Països Catalans 26, 43007, Tarragona, Spain
2 LAM (Laboratoire d’Astrophysique de Marseille), CNRS, Aix Marseille Université, UMR 7326, 13388 Marseille, France
Received: 1 May 2016
Accepted: 13 February 2017
We present two methods for bar strength measurement on disc galaxies based on a two-dimensional Fourier analysis of their images. Our methods are able to recover the whole spiral structure of disc galaxies and are very robust when comparing the results from images obtained with different filters. In particular, these methods are capable of detecting small bars regardless of the filter used to obtain the galaxy image. Our relative measurements of bar strength show a good agreement with different bar indicators used in the literature. We use our methods to determine the general morphologies indicated in the Third Reference Catalog of Bright Galaxies (RC3 catalogue) classified as non-barred (SA), mildly barred (SAB), or barred (SB) galaxies. Our numerical indicators are in good agreement with the three galaxy populations estimated visually.
Key words: galaxies: structure / galaxies: spiral
© ESO, 2017