Han 2010 长暴的宿主星系大多可以WR星

主要内容:
8个里边找到了5个有

精彩摘抄:


文章信息:

· Find Similar Abstracts (with default settings below)

· Electronic Refereed Journal Article (HTML)

· Full Refereed Journal Article (PDF/Postscript)

· arXiv e-print (arXiv:1001.2476)

· On-line Data

· References in the article

· Citations to the Article (4) (Citation History)

· Refereed Citations to the Article

· SIMBAD Objects (11)

· Also-Read Articles (Reads History)

·

· Translate This Page

Title:		The Wolf-Rayet features and mass-metallicity relation of long-duration gamma-ray burst host galaxies
Authors:		Han, X. H.; Hammer, F.; Liang, Y. C.; Flores, H.; Rodrigues, M.; Hou, J. L.; Wei, J. Y.
Affiliation:		AA(Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, the Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, PR China hxh@nao.cas.cn ; GEPI, Observatoire de Paris-Meudon, Meudon 92195, France; National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, PR China ; Graduate School of the Chinese Academy of Sciences, Beijing 100049, PR China), AB(GEPI, Observatoire de Paris-Meudon, Meudon 92195, France francois.hammer@obspm.fr), AC(National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, PR China), AD(GEPI, Observatoire de Paris-Meudon, Meudon 92195, France), AE(GEPI, Observatoire de Paris-Meudon, Meudon 92195, France), AF(Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, the Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, PR China), AG(National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, PR China)
Publication:		Astronomy and Astrophysics, Volume 514, id.A24 (A&A Homepage)
Publication Date:		05/2010
Origin:		EDP Sciences
Keywords:		gamma-ray burst: general, stars: Wolf-Rayet, galaxies: abundances, galaxies: fundamental parameters
DOI:		10.1051/0004-6361/200912475
Bibliographic Code:		2010A&A...514A..24H

Abstract

Aims: We gather optical spectra of 8 long-duration GRB host galaxies selected from the archival data of VLT/FORS2. We investigate whether or not Wolf-Rayet (WR) stars can be detected in these GRB host galaxies. We also estimate the physical properties of GRB host galaxies, such as metallicity.
Methods: We identify the WR features in these spectra by fitting the WR bumps and WR emission lines in blue and red bumps. We identify the subtypes of the WR stars, estimate the numbers of stars in each subtype, and calculate the WR/O star ratios. The (O/H) abundances of GRB hosts are inferred from both the electron temperature (T_e) and the metallicity-sensitive strong-line ratio (R₂₃), for which we break the R₂₃ degeneracy. We compare the environments of long-duration GRB host galaxies with those of other galaxies in terms of their luminosity (stellar mass)-metallicity relations (L-Z, M_*-Z).
Results: We detect WR stars in 5 GRB host galaxies with spectra of relatively high signal-to-noise ratios (S/N). In the comparison of L-Z, M_*-Z relations, we show that GRB hosts have lower metallicities than other samples of comparable luminosity and stellar mass. The presence of WR stars and the observed high WR/O star ratio, together with the low metallicity, support the "core-collapsar" model and imply that we are witnessing the first stage of star formation in the host regions of GRBs.

---

Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)