A new fitting concept for the robust determination of Sérsic model parameters
- Author(s)
- Iris Breda, Polychronis Papaderos, Jean Michel Gomes, Stergios Amarantidis
- Abstract
The Sérsic law (SL) offers a versatile functional form for the structural characterization of galaxies near and far. Whereas applying it to galaxies with a genuine SL luminosity distribution yields a robust determination of the Sérsic exponent eta and effective surface brightness $\mu_{\rm eff}$, this is not necessarily the case for galaxies whose surface brightness profiles (SBPs) appreciably deviate from the SL (eg, early-type galaxies with a depleted core and nucleated dwarf ellipticals, or most late-type galaxies-LTGs). In this general case of "imperfect" SL profiles, the best-fitting solution may significantly depend on the radius (or surface brightness) interval fit and corrections for point spread function (PSF) convolution effects. Such uncertainties may then affect, in a non-easily predictable manner, automated structural studies of galaxies. We present a fitting concept (iFIT) that permits a robust determination of the equivalent SL model for the general case of galaxies with imperfect SL profiles. iFIT has been extensively tested on synthetic data with a Sérsic index 0.3
- Organisation(s)
- Department of Astrophysics
- Journal
- Astronomy & Astrophysics
- ISSN
- 0004-6361
- Publication date
- 10-2019
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy
- Keywords
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/007d5076-4a66-478d-a8b1-1ad36d1e2049