Systematic study for gas-to-dust ratio of short gamma-ray burst afterglows
arXiv:1903.05963 · doi:10.1093/pasj/psz030
Abstract
Extra-galactic X-ray absorption and optical extinction are often found in gamma-ray burst (GRB) afterglows and they could be tracers of both circumburst and host galaxy environments. By performing spectral analyses for spectral energy distribution of 9 short GRB (SGRB) afterglows with known redshift, we investigated a ratio of the equivalent hydrogen column density to the dust extinction, N^{rest}_{H}/A^{rest}_{V}, in the rest frame of each SGRB. We found that the distribution of N^{rest}_{H}/A^{rest}_{V} is systematically smaller than the one for long GRBs, and is roughly consistent with the gas-to-dust ratio in the Milky Way. This result means that the measured gas-to-dust ratio of SGRBs would originate from the interstellar medium in each host galaxy. This scenario supports the prediction that SGRBs occur in non star-forming regions in the host galaxies.
15 pages, 4 figures
References in corpus (11)
- Multi-messenger Observations of a Binary Neutron Star Merger
- The Supernova -- Gamma-Ray Burst Connection
- An Ordinary Short Gamma-Ray Burst with Extraordinary Implications: Fermi-GBM Detection of GRB 170817A
- The Physics of Gamma-Ray Bursts and Relativistic Jets
- INTEGRAL Detection of the First Prompt Gamma-Ray Signal Coincident with the Gravitational Wave Event GW170817
- An online repository of Swift/XRT light curves of GRBs
- Long gamma-ray bursts and core-collapse supernovae have different environments
- The environment of the binary neutron star merger GW170817
- Multicolor observations of the afterglow of the short/hard GRB 050724
- Bimodal Long-Lasting Components in Short Gamma-Ray Bursts: Promising Electromagnetic Counterparts to Neutron Star Binary Mergers
- A long optical plateau in the afterglow of the Extended Emission short GRB 150424A: Evidence for energy injection by a magnetar?