A Deep K -Band Photometric Survey of Merger Remnants

Abstract

We present K -band photometry for 51 candidate merger remnants to assess the viability of whether spiral-spiral mergers can produce bona fide elliptical galaxies. Using both the de Vaucouleurs r 1/4 and Sérsic r 1/ n fitting laws, it is found that the stellar component in a majority of the galaxies in the sample has undergone violent relaxation. However, the sample shows evidence for incomplete phase mixing. The analysis also indicates the presence of "excess light" in the surface brightness profiles of nearly one-third of the merger remnants. Circumstantial evidence suggests that this is due to the effects of a starburst induced by the dissipative collapse of the gas. The integrated light of the galaxies also shows that mergers can make L * elliptical galaxies, in contrast to earlier infrared studies. The isophotal shapes and related structural parameters are also discussed, including the fact that 70% of the sample show evidence for disky isophotes. The data and results presented are part of a larger photometric and spectroscopic campaign to thoroughly investigate a large sample of mergers in the local universe.