2024/08/21 by Erin Boettcher, Edmund Hodges‐Kluck, Boettcher, Erin +1
Engineering · Physics and Astronomy · #Astronomical Observations and Instrumentation #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #History and Developments in Astronomy #Photocathodes and Microchannel Plates
paper · pdf · doi:10.48550/arxiv.2408.11912
openalex publication_date 2024/08/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Circumgalactic dust grains trace the circulation of mass and metals between star-forming regions and gaseous galactic halos, giving insight into feedback and tidal stripping processes. We perform a search for ultraviolet (UV) reflection nebulae produced by extraplanar dust around 551 nearby (D < 100 Mpc), edge-on disk galaxies using archival near-UV (NUV) and far-UV (FUV) images from GALEX, accounting for the point-spread function (FWHM = 4''-5''). We detect extraplanar emission ubiquitously in stacks of galaxies binned by morphology and star-formation rate, with scale heights of hh = 1 - 2.3 kpc and ≈ 10% of the total (reddened) flux in the galaxy found beyond the B-band isophotal level of μB = 25 mag arcsec-2. This emission is detected in 7% of the individual galaxies, and an additional one third have at least 5% of their total flux found beyond μB = 25 mag arcsec-2 in a disk component. The extraplanar luminosities and colors are consistent with reflection nebulae rather than stellar halos and indicate that, on average, disk galaxies have an extraplanar dust mass of 5% - 15% of that in their interstellar medium. This suggests that recycled material composes at least a third of the inner circumgalactic medium (R < 10 kpc) in ∼ L* galaxies.