Isophotal shapes of early-type galaxies to very faint levels
arXiv:1407.5120 · doi:10.1088/0004-637X/787/2/102
Abstract
We report on a study of the isophotal shapes of early-type galaxies, to very faint levels reaching ~ 0.1% of the sky brightness. The galaxies are from the Large Format Camera (LFC) fields obtained using the Palomar 5 m Hale telescope, with integrated exposures ranging from 1 to 4 hours in the SDSS r, i and z bands. The shapes of isophotes of early-type galaxies are important as they are correlated with the physical properties of the galaxies and are influenced by galaxy formation processes. In this paper we report on a sample of 132 E and SO galaxies in one LFC field. We have redshifts for 53 of these, obtained using AAOmega on the Anglo-Australian Telescope. The shapes of early-type galaxies often vary with radius. We derive average values of isophotal shape parameters in four different radial bins along the semi-major axis in each galaxy. We obtain empirical fitting formulae for the probability distribution of the sophotal parameters in each bin and investigate for possible correlations with other global properties of the galaxies. Our main finding is that the isophotal shapes of the inner regions are statistically different from those in the outer regions. This suggests that the outer and inner parts of early-type galaxies have evolved somewhat independently.
62 pages, 11 figures, 8 tables, published in ApJ
References in corpus (10)
- K-corrections and filter transformations in the ultraviolet, optical, and near infrared
- Multiple minor mergers: formation of elliptical galaxies and constraints for the growth of spiral disks
- The 2dF-SDSS LRG and QSO (2SLAQ) Luminous Red Galaxy Survey
- Are disk galaxies the progenitors of giant ellipticals?
- Isophotal Shapes of Elliptical/S0 Galaxies from the Sloan Digital Sky Survey
- Multi-Object Spectroscopy Field Configuration by Simulated Annealing
- Measurement of non-axisymmetry in centres of advanced mergers of galaxies
- The Isophotal Structure of Early-Type Galaxies in the SDSS: Dependence on AGN Activity and Environment
- Isophotal Structure and Dust Distribution in Radio-Loud Elliptical Galaxies
- Unravelling the morphologies of Luminous Compact Galaxies using the HST/ACS GOODS survey