English

Ultraviolet Halos Around Spiral Galaxies. I. Morphology

Astrophysics of Galaxies 2016-12-14 v1

Abstract

We examine ultraviolet halos around a sample of highly inclined galaxies within 25 Mpc to measure their morphology and luminosity. Despite contamination from galactic light scattered into the wings of the point-spread function, we find that UV halos occur around each galaxy in our sample. Around most galaxies the halos form a thick, diffuse disk-like structure, but starburst galaxies with galactic superwinds have qualitatively different halos that are more extensive and have filamentary structure. The spatial coincidence of the UV halos above star-forming regions, the lack of consistent association with outflows or extraplanar ionized gas, and the strong correlation between the halo and galaxy UV luminosity suggest that the UV light is an extragalactic reflection nebula. UV halos may thus represent 1-10 million solar masses of dust within 2-10 kpc of the disk, whose properties may change with height in starburst galaxies.

Keywords

Cite

@article{arxiv.1610.02404,
  title  = {Ultraviolet Halos Around Spiral Galaxies. I. Morphology},
  author = {Edmund Hodges-Kluck and Julian Cafmeyer and Joel Bregman},
  journal= {arXiv preprint arXiv:1610.02404},
  year   = {2016}
}

Comments

29 pages, 10 tables, 12 figures, accepted to ApJ

R2 v1 2026-06-22T16:14:43.729Z