2012ApJ...756...25M


C.D.S. - SIMBAD4 rel 1.7 - 2021.05.06CEST01:12:35

2012ApJ...756...25M - Astrophys. J., 756, 25 (2012/September-1)

The optically unbiased GRB host (TOUGH) survey. IV. Lyα emitters.

MILVANG-JENSEN B., FYNBO J.P.U., MALESANI D., HJORTH J., JAKOBSSON P. and MOLLER P.

Abstract (from CDS):

We report the results of a spectroscopic search for Lyα emission from gamma-ray burst (GRB) host galaxies. Based on a well-defined parent sample (the TOUGH sample) of 69 x-ray-selected Swift GRBs, we have targeted the hosts of a subsample of 20 GRBs known from afterglow spectroscopy to be in the redshift range z = 1.8-4.5. We have obtained spectroscopy using the FORS1 instrument at the ESO Very Large Telescope to search for the presence of Lyα emission from the host galaxies. We detect Lyα emission from 7 out of the 20 hosts, with the typical limiting 3σ line flux being 8x10–18 erg/cm2/s, corresponding to an Lyα luminosity of 6x1041 erg/s at z = 3. The Lyα luminosities for the seven hosts in which we detect Lyα emission are in the range (0.6-2.3) x 1042 erg/s, corresponding to star formation rates of 0.6-2.1 M/yr (not corrected for extinction). The rest-frame Lyα equivalent widths (EWs) for the seven hosts are in the range 9-40 Å. For 6 of the 13 hosts for which Lyα is not detected, we place fairly strong 3σ upper limits on the EW (<20 Å), while for others the EW is either unconstrained or has a less constraining upper limit. We find that the distribution of Lyα EWs is inconsistent with being drawn from the Lyα EW distribution of bright Lyman break galaxies (LBGs) at the 98.3% level, in the sense that the TOUGH hosts on average have larger EWs than bright LBGs. We can exclude an early indication, based on a smaller, heterogeneous sample of pre-Swift GRB hosts, that all GRB hosts are Lyα emitters. We find that the TOUGH hosts on average have lower EWs than the pre-Swift GRB hosts, but the two samples are only inconsistent at the 92% level. The velocity centroid of the Lyα line (where detected) is redshifted by 200-700 km/s with respect to the systemic velocity (taken to be the afterglow redshift), similar to what is seen for LBGs, possibly indicating star-formation-driven outflows from the host galaxies. There seems to be a trend between the Lyα EW and the optical to x-ray spectral index of the afterglow (βOX), hinting that dust plays a role in the observed strength and even presence of Lyα emission.

Abstract Copyright:

Journal keyword(s): dust, extinction - galaxies: fundamental parameters - galaxies: high-redshift - galaxies: star formation - gamma-ray burst: general - surveys

Simbad objects: 44

goto Full paper

goto View the reference in ADS

Number of rows : 44

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 GRB 070110 gB 00 03 39.270 -52 58 27.00 21.8 21.9 21.2     ~ 178 0
2 GRB 070611 gB 00 07 58.000 -29 45 19.40           ~ 83 0
3 GRB 071031 gB 00 25 37.40 -58 03 33.9           ~ 147 0
4 GRB 021004 gB 00 26 54.68 +18 55 41.6           ~ 519 0
5 GRB 050908 gB 01 21 50.750 -12 57 17.20           ~ 160 0
6 GRB 060908 gB 02 07 18.360 +00 20 31.20 16.99 18.34 16.85     ~ 180 0
7 GRB 070721B gB 02 12 32.98 -02 11 39.8           ~ 104 0
8 GRB 070802 gB 02 27 35.91 -55 31 39.1           ~ 138 0
9 GRB 070129 gB 02 28 00.940 +11 41 04.00       21.3   ~ 95 0
10 GRB 050603 gB 02 39 56.839 -25 10 54.92     18.48     ~ 150 0
11 GRB 060115 gB 03 36 08.400 +17 20 43.00           ~ 152 0
12 GRB 060223A gB 03 40 49.560 -17 07 48.40     17.90     ~ 79 0
13 GRB 050915A gB 05 26 44.804 -28 00 59.27           ~ 69 0
14 GRB 070306 gB 09 52 23.220 +10 28 55.20           ~ 182 1
15 GRB 090423 gB 09 55 33.19 +18 08 57.7           ~ 318 0
16 GRB 030323 gB 11 06 09.4 -21 46 13           ~ 127 1
17 GRB 011211 gB 11 15 16 -21 56.0           ~ 289 0
18 GRB 971214 gB 11 56 26.4 +65 12 01           ~ 434 1
19 GRB 030429 gB 12 13 07.495 -20 54 49.54     23.70     ~ 122 0
20 GRB 070810A gB 12 39 51.18 +10 45 02.8           ~ 65 0
21 GRB 050730 gB 14 08 17.090 -03 46 18.90   20.32 17.68     ~ 288 0
22 GRB 090205 gB 14 43 40.00 -27 50 51.4           ~ 74 0
23 GRB 060814 gB 14 45 21.480 +20 35 11.80           ~ 191 0
24 GRB 060714 gB 15 11 26.450 -06 33 58.30   20.21 18.54     ~ 172 0
25 GRB 060526 gB 15 31 18.360 +00 17 04.90   18.31 17.16     ~ 242 0
26 GRB 060923B gB 15 52 46.740 -30 54 11.30 19.80         ~ 33 0
27 GRB 050401 gB 16 31 28.84 +02 11 14.5           ~ 308 0
28 GRB 000926 gB 17 04 15 +51 46.0           ~ 345 0
29 GRB 060926 gB 17 35 43.660 +13 02 18.60     19.36     ~ 119 0
30 GRB 050315 gB 20 25 54.100 -42 36 02.19           ~ 197 0
31 GRB 100621A gB 21 01 13.12 -51 06 22.5           ~ 155 0
32 GRB 070419B gB 21 02 49.820 -31 15 49.30   20.35       ~ 69 0
33 GRB 050922C gB 21 09 33.000 -08 45 30.10 15.15 15.86 14.69     ~ 257 0
34 GRB 060605 gB 21 28 37.320 -06 03 31.30   20.12 16.53     ~ 172 0
35 GRB 061110B gB 21 35 40.400 +06 52 34.10           ~ 77 0
36 GRB 060607 gB 21 58 50.400 -22 29 46.70 18.49 16.67 15.09     ~ 266 0
37 GRB 060604 gB 22 28 55.010 -10 54 55.80 20.34 20.31       ~ 110 0
38 GRB 050820A gB 22 29 38.110 +19 33 37.10 18.33 19.00 18.47     ~ 344 0
39 GRB 070506 gB 23 08 52.390 +10 43 20.30     19.04     ~ 71 0
40 GRB 051001 gB 23 23 48.580 -31 31 25.70           ~ 69 0
41 GRB 070103 gB 23 30 13.750 +26 52 33.70           ~ 59 0
42 GRB 060707 gB 23 48 19.000 -17 54 17.00     19.79     ~ 142 0
43 GRB 061222A gB 23 53 03.419 +46 31 58.60           ~ 139 0
44 GRB 050819 gB 23 55 01.650 +24 51 38.80           ~ 65 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2012ApJ...756...25M and select 'bookmark this link' or equivalent in the popup menu


2021.05.06-01:12:35

© Université de Strasbourg/CNRS

    • Contact