Mannucci 2010 长暴的宿主星系的金属丰度和低质量星系的金属丰度

主要内容:


精彩摘抄:


文章信息:

· Find Similar Abstracts (with default settings below)

· arXiv e-print (arXiv:1011.4506)

· References in the Article

· Also-Read Articles (Reads History)

·

· Translate This Page

Title:		The metallicity of the long GRB hosts and the Fundamental Metallicity Relation of low-mass galaxies
Authors:		Mannucci, F.; Salvaterra, R.; Campisi, M. A.
Publication:		eprint arXiv:1011.4506
Publication Date:		11/2010
Origin:		ARXIV
Keywords:		Astrophysics - Cosmology and Extragalactic Astrophysics
Comment:		6 pages, submitted to MNRAS
Bibliographic Code:		2010arXiv1011.4506M

Abstract

We investigate the metallicity properties of host galaxies of long Gamma-ray Bursts (GRBs) in the light of the Fundamental Metallicity Relation (FMR), the tight dependence of metallicity on mass and SFR recently discovered for SDSS galaxies with stellar masses above 10^9.2 Msun. As most of the GRB hosts have masses below this limit, the FMR can only be used after an extension towards lower masses. At this aim, we study the FMR for galaxies with masses down to ~10^8.3 Msun, finding that the FMR does extend smoothly at lower masses, albeit with a much larger scatter. We then compare the resulting FMR with the metallicity properties of 18 host galaxies of long GRBs. While the GRB hosts show a systematic offset with respect to the mass-metallicity relation, they are fully consistent with the FMR. This shows that the difference with the mass-metallicity relation is due to higher than average SFRs, and that GRBs do not preferentially select low-metallicity hosts among the star-forming galaxies. The apparent low metallicity is therefore a consequence of the occurrence of long GRB in low mass, actively star-forming galaxies, known to dominate the current cosmic SFR.

---

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