2020/10/02 by Ivana Barisic, Ivana Barišić, Camilla Pacifici +14
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Attenuation #Galaxies: Formation, Evolution, Phenomena #Galaxy #Light curve #Milky Way #Photometry (optics) #Spectral line #Spectral slope #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/abba37
15 pages, 10 figures, 1 table. Accepted for publication in The Astrophysical Journal
arxiv created 2020/10/02 · openalex created_date 2020/10/08 · openalex publication_date 2020/11/01 · arxiv updated 2020/11/18 · openalex updated_date 2026/08/06
Abstract We present a novel approach to measure the attenuation curves of 485 individual star-forming galaxies with > 10 10 M ⊙ based on deep optical spectra from the VLT/VIMOS LEGA-C survey and multiband photometry in the COSMOS field. Most importantly, we find that the attenuation curves in the rest-frame 3000–4500 Å range are typically almost twice as steep as the Milky Way, LMC, SMC, and Calzetti attenuation curves, which is in agreement with recent studies of the integrated light of present-day galaxies. The attenuation at 4500 Å and the slope strongly correlate with the galaxy inclination: face-on galaxies show less attenuation and steeper curves compared to edge-on galaxies, suggesting that geometric effects dominate observed variations in attenuation. Our new method produces 2175 Å UV bump detections for 260 individual galaxies. Even though obvious correlations between UV bump strength and global galaxy properties are absent, strong UV bumps are most often seen in face-on, lower-mass galaxies (10 < log 10 ( M * / M ⊙ ) < 10.5) with low overall attenuation. Finally, we produce a typical attenuation curve for star-forming galaxies at z ∼ 0.8; this prescription represents the effect of dust on the integrated spectral energy distributions of high-redshift galaxies more accurately than commonly used attenuation laws.