English

Misalignment between cold gas and stellar components in early-type galaxies

Astrophysics of Galaxies 2015-06-23 v1

Abstract

Recent work suggests blue ellipticals form in mergers and migrate quickly from the blue cloud of star-forming galaxies to the red sequence of passively evolving galaxies, perhaps as a result of black hole feedback. Such rapid reddening of stellar populations implies that large gas reservoirs in the pre-merger star-forming pair must be depleted on short time scales. Here we present pilot observations of atomic hydrogen gas in four blue early-type galaxies that reveal increasing spatial offsets between the gas reservoirs and the stellar components of the galaxies, with advancing post-starburst age. Emission line spectra show associated nuclear activity in two of the merged galaxies, and in one case radio lobes aligned with the displaced gas reservoir. These early results suggest that a kinetic process (possibly feedback from black hole activity) is driving the quick truncation of star formation in these systems, rather than a simple exhaustion of gas supply.

Keywords

Cite

@article{arxiv.1501.07653,
  title  = {Misalignment between cold gas and stellar components in early-type galaxies},
  author = {O. Ivy Wong and K. Schawinski and G. I. G. Józsa and C. M. Urry and C. J. Lintott and B. D. Simmons and S. Kaviraj and K. L. Masters},
  journal= {arXiv preprint arXiv:1501.07653},
  year   = {2015}
}

Comments

12 pages, 9 figures, accepted for publication in MNRAS

R2 v1 2026-06-22T08:16:18.578Z