| Title | The 2175 angstrom Dust Feature in Star-forming Galaxies at 1.3 <= z <= 1.8: The Dependence on Stellar Mass and Specific Star Formation Rate |
| Authors | Kashino, Daichi Lilly, Simon J. Silverman, John D. Renzini, Alvio Daddi, Emanuele Bardelli, Sandro Cucciati, Olga Kartaltepe, Jeyhan S. Mainieri, Vincenzo Pello, Roser Peng, Ying-jie Sanders, David B. Zucca, Elena |
| Affiliation | Swiss Fed Inst Technol, Dept Phys, Wolfgang Pauli Str 27, CH-8093 Zurich, Switzerland Nagoya Univ, Inst Adv Res, Chikusa Ku, Nagoya, Aichi 4648601, Japan Univ Tokyo, Kavli Inst Phys & Math Universe, Kashiwa, Chiba 2778583, Japan Univ Tokyo, Sch Sci, Dept Astron, 7-3-1 Hongo, Tokyo 1130033, Japan INAF, Osservatorio Astron Padova, Vicolo DellOsservatorio 5, I-35122 Padua, Italy Univ Paris, Univ Paris Saclay, CEA, Irfu,DAp,AIM,CNRS, F-91191 Gif Sur Yvette, France INAF, Osservatorio Astrofis & Sci Spazio Bologna, Via Gobetti 93-3, I-40129 Bologna, Italy Rochester Inst Technol, Sch Phys & Astron, 84 Lomb Mem Dr, Rochester, NY 14623 USA European Southern Observ, Karl Schwarzschild Str 2, Garching, Germany Aix Marseille Univ, CNRS, CNES, LAM Lab Astrophys Marseille,UMR 7326, F-13388 Marseille, France Peking Univ, Kavli Inst Astron & Astrophys, 5 Yiheyuan Rd, Beijing 100871, Peoples R China Peking Univ, Sch Phys, Dept Astron, 5 Yiheyuan Rd, Beijing 100871, Peoples R China Univ Hawaii, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA |
| Issue Date | Mar-2021 |
| Publisher | ASTROPHYSICAL JOURNAL |
| Abstract | We present direct spectroscopic measurements of the broad 2175 A absorption feature in 505 star-forming main-sequence galaxies at 1.3 <= z <= 1.8 using individual and stacked spectra from the zCOSMOS-deep survey. Significant 2175 A excess absorption features of moderate strength are measured, especially in the composite spectra. The excess absorption is well described by a Drude profile. The bump amplitude expressed in units of k(lambda) = A(lambda)/E(B - V), relative to the featureless Calzetti et al. law, has a range B-k 0.2-0.8. The bump amplitude decreases with the specific star formation rate (sSFR), while it increases moderately with the stellar mass. However, a comparison with local "starburst" galaxies shows that the high-redshift main-sequence galaxies have stronger bump features, despite having a higher sSFR than the local sample. Plotting the bump strength against the Delta logsSFR equivalent to log (SFR/SFRMS) relative to the main sequence, however, brings the two samples into much better concordance. This may indicate that it is the recent star formation history of the galaxies that determines the bump strength through the destruction of small carbonaceous grains by supernovae and intense radiation fields coupled with the time delay of similar to 1 Gyr in the appearance of carbon-rich asymptotic giant branch stars. |
| URI | http://hdl.handle.net/20.500.11897/609034 |
| ISSN | 0004-637X |
| DOI | 10.3847/1538-4357/abdf62 |
| Indexed | SCI(E) |
| Appears in Collections: | 科维理天文与天体物理研究所 物理学院 |
