|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'504'585
Articles rated: 2609
24 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
GRB hosts through cosmic time - VLT/X-shooter emission-line spectroscopy of 96 GRB-selected galaxies at 0.1 < z < 3.6 | | T. Krühler
; D. Malesani
; J. P. U. Fynbo
; O. E. Hartoog
; J. Hjorth
; P. Jakobsson
; D. A. Perley
; A. Rossi
; P. Schady
; S. Schulze
; N. R. Tanvir
; S. D. Vergani
; K. Wiersema
; P. M. J. Afonso
; J. Bolmer
; Z. Cano
; S. Covino
; V. D'Elia
; A. de Ugarte Postigo
; R. Filgas
; M. Friis
; J. F. Graham
; J. Greiner
; P. Goldoni
; A. Gomboc
; F. Hammer
; J. Japelj
; D. A. Kann
; L. Kaper
; S. Klose
; A. J. Levan
; G. Leloudas
; B. Milvang-Jensen
; A. Nicuesa Guelbenzu
; E. Palazzi
; E. Pian
; S. Piranomonte
; R. Sanchez-Ramirez
; S. Savaglio
; J. Selsing
; G. Tagliaferri
; P. M. Vreeswijk
; D. J. Watson
; D. Xu
; | | Date: |
25 May 2015 | | Abstract: | We present data and initial results from VLT/X-shooter emission-line
spectroscopy of 96 GRB-selected galaxies at 0.1<z<3.6, the largest sample of
GRB host spectroscopy available to date. The majority of our GRBs was detected
by Swift and 76% are at 0.5<z<2.5 with a median z~1.6. Based on Balmer and/or
forbidden lines of oxygen, nitrogen and neon, we measure systemic redshifts,
star-formation rates, visual attenuations (A_V), oxygen abundances and
emission-line widths (sigma). We find a strong change of the typical physical
properties of GRB hosts with redshift. The median SFR, for example, increases
from ~0.6 M_sun/yr at z~0.6 up to ~15 M_sun/yr at z~2. A higher ratio of
[OIII]/[OII] at higher redshifts leads to an increasing distance of
GRB-selected galaxies to the locus of local galaxies in the BPT diagram. Oxygen
abundances of the galaxies are distributed between 12+log(O/H)=7.9 and
12+log(O/H)=9.0 with a median of 12+log(O/H)~8.5. The fraction of GRB-selected
galaxies with super-solar metallicities is around 20% at z<1 in the adopted
metallicity scale. This is significantly less than the fraction of
star-formation in similar galaxies, illustrating that GRBs are scarce in
high-metallicity environments. At z~3, sensitivity limits us to probing only
the most luminous GRB hosts for which we derive metallicities of Z ~< 0.5
Z_sun. Together with a high incidence of galaxies with similar metallicity in
our sample at z~1.5, this indicates that the metallicity dependence observed at
low redshift will not be dominant at z~3. | | Source: | arXiv, 1505.6743 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER