Volume 535, November 2011
|Number of page(s)||10|
|Published online||30 November 2011|
GRB 091127/SN 2009nz and the VLT/X-shooter spectroscopy of its host galaxy: probing the faint end of the mass-metallicity relation⋆
INAF, Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807
2 GEPI-Observatoire de Paris Meudon, 5 place Jules Jansen, 92195 Meudon, France
3 Laboratoire Astroparticule et Cosmologie, 10 rue A. Domon et L. Duquet, 75205 Paris Cedex 13, France
4 Instituto de Astrofísica de Andalucía (IAA-CSIC), Glorieta de la Astronomía s/n, 18008 Granada, Spain
5 Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
6 Dipartimento di Fisica e Matematica, Università dell’Insubria, via Valleggio 7, 22100 Como, Italy
7 Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen Ø, Denmark
8 INAF, Osservatorio Astronomico di Roma, via di Frascati 33, 00040 Monte Porzio Catone, Rome, Italy
9 ASI-Science Data Center, via Galileo Galilei, 00044 Frascati, Italy
10 European Southern Observatory, Alonso de Córdova 3107, Vitacura, Casilla 19001, Santiago 19, Chile
11 Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura-Santiago, Chile
12 INAF, IASF di Bologna, via Gobetti 101, 40129 Bologna, Italy
13 Service d’Astrophysique, DSM/IRFU/SAp, CEA-Saclay, 91191 Gif-sur-Yvette, France
14 Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, 107 Reykjavík, Iceland
15 Astronomical Institute Anton Pannekoek, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
16 The Oskar Klein Centre, Department of Astronomy, AlbaNova, Stockholm University, 10691 Stockholm, Sweden
17 Department of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK
Accepted: 14 September 2011
We perform a detailed study of the gamma-ray burst GRB 091127/SN 2009nz host galaxy at z = 0.490 using the VLT/X-shooter spectrograph in slit and integral-field unit (IFU) mode. From the analysis of the optical and X-ray afterglow data obtained from ground-based telescopes and Swift-XRT, we confirm the presence of a bump associated with SN 2009nz and find evidence of a possible jet break in the afterglow lightcurve. The X-shooter afterglow spectra reveal several emission lines from the underlying host, from which we derive its integrated properties. These properties agree with those of previously studied GRB-SN hosts and, more generally, with those of the long GRB host population. We use the Hubble Space Telescope and ground-based images of the host to determine its stellar mass (M⋆). Our results extend to lower M⋆ values the M-Z plot derived for the sample of long GRB hosts at 0.3 < z < 1.0 adding new information to probe the faint end of the M-Z relation and the shift of the LGRB host M-Z relation from that found from emission-line galaxy surveys. Thanks to the IFU spectroscopy, we can build the two-dimensional (2D) velocity, velocity dispersion, and star formation rate (SFR) maps. They show that the host galaxy has perturbed rotation kinematics with evidence of a SFR enhancement consistent with the afterglow position.
Key words: gamma-ray burst: individual: GRB 091127 / supernovae: individual: SN 2009nz / galaxies: ISM / galaxies: evolution
© ESO, 2011
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.