Please use this identifier to cite or link to this item:
http://hdl.handle.net/20.500.12386/25007
Title: | Are long gamma-ray bursts biased tracers of star formation? Clues from the host galaxies of the Swift/BAT6 complete sample of bright LGRBs. II. Star formation rates and metallicities at z < 1 | Authors: | Japelj, J. Vergani, S. D. SALVATERRA, Ruben D'AVANZO, Paolo MANNUCCI, FILIPPO Fernandez-Soto, A. Boissier, S. HUNT, Leslie Kipp Atek, H. Rodríguez-Muñoz, L. SCODEGGIO, MARCO CRISTIANI, Stefano Le Floc'h, E. Flores, H. Gallego, J. GHIRLANDA, Giancarlo Gomboc, A. Hammer, F. Perley, D. A. Pescalli, A. Petitjean, P. Puech, M. Rafelski, M. TAGLIAFERRI, Gianpiero |
Issue Date: | 2016 | Journal: | ASTRONOMY & ASTROPHYSICS | Number: | 590 | First Page: | A129 | Abstract: | Aims: Long gamma-ray bursts (LGRBs) are associated with the deaths of massive stars and might therefore be a potentially powerful tool for tracing cosmic star formation. However, especially at low redshifts (z< 1.5) LGRBs seem to prefer particular types of environment. Our aim is to study the host galaxies of a complete sample of bright LGRBs to investigate the effect of the environment on GRB formation. <BR /> Methods: We studied host galaxy spectra of the Swift/BAT6 complete sample of 14 z< 1 bright LGRBs. We used the detected nebular emission lines to measure the dust extinction, star formation rate (SFR), and nebular metallicity (Z) of the hosts and supplemented the data set with previously measured stellar masses M<SUB>⋆</SUB>. The distributions of the obtained properties and their interrelations (e.g. mass-metallicity and SFR-M<SUB>⋆</SUB> relations) are compared to samples of field star-forming galaxies. <BR /> Results: We find that LGRB hosts at z< 1 have on average lower SFRs than if they were direct star formation tracers. By directly comparing metallicity distributions of LGRB hosts and star-forming galaxies, we find a good match between the two populations up to 12 +log ≤ft( frac{OHright)} 8.4-8.5, after which the paucity of metal-rich LGRB hosts becomes apparent. The LGRB host galaxies of our complete sample are consistent with the mass-metallicity relation at similar mean redshift and stellar masses. The cutoff against high metallicities (and high masses) can explain the low SFR values of LGRB hosts. We find a hint of an increased incidence of starburst galaxies in the Swift/BAT6 z< 1 sample with respect to that of a field star-forming population. Given that the SFRs are low on average, the latter is ascribed to low stellar masses. Nevertheless, the limits on the completeness and metallicity availability of current surveys, coupled with the limited number of LGRB host galaxies, prevents us from investigating more quantitatively whether the starburst incidence is such as expected after taking into account the high-metallicity aversion of LGRB host galaxies. <P />Based on observations at ESO, Program IDs: 077.D-0425, 177.A-0591, 080.D-0526, 081.A-0856, 082.D-0276, 083.D-0069, 084.A-0303, 084.A-0260, 086.A-0644, 086.B-0954, 089.A-0868, 090.A-0760, 095.D-0560.The reduced spectra are available in the ESO archive as Phase 3 data products and in the GTC archive. | URI: | http://hdl.handle.net/20.500.12386/25007 | URL: | https://www.aanda.org/articles/aa/abs/2016/06/aa28314-16/aa28314-16.html | ISSN: | 0004-6361 | DOI: | 10.1051/0004-6361/201628314 | Bibcode ADS: | 2016A&A...590A.129J | Fulltext: | open |
Appears in Collections: | 1.01 Articoli in rivista |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
aa28314-16.pdf | PDF editoriale | 1.62 MB | Adobe PDF | View/Open |
Page view(s)
74
checked on Apr 23, 2024
Download(s)
11
checked on Apr 23, 2024
Google ScholarTM
Check
Altmetric
Altmetric
Items in DSpace are published in Open Access, unless otherwise indicated.