Abstract
We present the stellar population properties of 69 short gamma-ray burst (GRB) host galaxies, representing the largest uniformly modeled sample to date. Using the Prospector stellar population inference code, we jointly fit photometry and/or spectroscopy of each host galaxy. We find a population median redshift of z = 0.64 − 0.32 + 0.83 (68% confidence), including nine photometric redshifts at z ≳ 1. We further find a median mass-weighted age of t m = 0.8 − 0.53 + 2.71 Gyr, stellar mass of log(M */M ⊙) = 9.69 − 0.65 + 0.75 , star formation rate of SFR = 1.44 − 1.35 + 9.37 M ⊙ yr−1, stellar metallicity of log(Z */Z ⊙) = − 0.38 − 0.42 + 0.44 , and dust attenuation of A V = 0.43 − 0.36 + 0.85 mag (68% confidence). Overall, the majority of short GRB hosts are star-forming (≈84%), with small fractions that are either transitioning (≈6%) or quiescent (≈10%); however, we observe a much larger fraction (≈40%) of quiescent and transitioning hosts at z ≲ 0.25, commensurate with galaxy evolution. We find that short GRB hosts populate the star-forming main sequence of normal field galaxies, but do not include as many high-mass galaxies as the general galaxy population, implying that their binary neutron star (BNS) merger progenitors are dependent on a combination of host star formation and stellar mass. The distribution of ages and redshifts implies a broad delay-time distribution, with a fast-merging channel at z > 1 and a decreased neutron star binary formation efficiency from high to low redshifts. If short GRB hosts are representative of BNS merger hosts within the horizon of current gravitational wave detectors, these results can inform future searches for electromagnetic counterparts. All of the data and modeling products are available on the Broadband Repository for Investigating Gamma-ray burst Host Traits website.
| Original language | English (US) |
|---|---|
| Article number | 57 |
| Journal | Astrophysical Journal |
| Volume | 940 |
| Issue number | 1 |
| DOIs | |
| State | Published - Nov 1 2022 |
Funding
This research was supported in part through the computational resources and staff contributions provided for the Quest high performance computing facility at Northwestern University, which is jointly supported by the Office of the Provost, the Office for Research, and Northwestern University Information Technology. We thank the anonymous referee for valuable insight and suggestions. A.E.N. acknowledges support from the Henry Luce Foundation through a Graduate Fellowship in Physics and Astronomy. The Fong Group at Northwestern acknowledges support by the National Science Foundation under grant Nos. AST-1814782, AST-1909358 and CAREER grant No. AST-2047919. W.F. gratefully acknowledges support by the David and Lucile Packard Foundation, the Alfred P. Sloan Foundation, and the Research Corporation for Science Advancement through Cottrell Scholar Award 28284. Support for M.Z. was provided by NASA through the NASA Hubble Fellowship grant HST-HF2-51474.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Y.D. is supported by the National Science Foundation Graduate Research Fellowship under grant No. DGE-1842165. A.L. is supported by the European Research Council (ERC) under the European Union\u2019s Horizon 2020 research and innovation program (grant agreement No. 725246). This work is based on observations taken by the 3D-HST Treasury Program (GO 12177 and 12328) with the NASA/ESA HST, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science