TY - JOUR
T1 - The Properties of the Host Galaxy and the Immediate Environment of GRB 980425/SN 1998bw from the Multiwavelength Spectral Energy Distribution
AU - Michałowski, Michał J.
AU - Hjorth, Jens
AU - Malesani, Daniele
AU - Michałowski, Tadeusz
AU - Castro Cerón, José María
AU - Reinfrank, Robert F.
AU - Garrett, Michael A.
AU - Fynbo, Johan P. U.
AU - Watson, Darach J.
AU - Jørgensen, Uffe G.
PY - 2009/3/1
Y1 - 2009/3/1
N2 - We present an analysis of the spectral energy distribution (SED) of the
galaxy ESO 184-G82, the host of the closest known long gamma-ray burst
(GRB) 980425 and its associated supernova (SN) 1998bw. We use our
observations obtained at the Australia Telescope Compact Array (the
third >3σ radio detection of a GRB host) as well as archival
infrared and ultraviolet (UV) observations to estimate its star
formation state. We find that ESO 184-G82 has a UV star formation rate
(SFR) and stellar mass consistent with the population of cosmological
GRB hosts and of local dwarf galaxies. However, it has a higher specific
SFR (per unit stellar mass) than luminous spiral galaxies. The mass of
ESO 184-G82 is dominated by an older stellar population in contrast to
the majority of GRB hosts. The Wolf-Rayet region ~800 pc from the SN
site experienced a starburst episode during which the majority of its
stellar population was built up. Unlike that of the entire galaxy, its
SED is similar to those of cosmological submillimeter/radio-bright GRB
hosts with hot dust content. These findings add to the picture that in
general, the environments of GRBs on 1-3 kpc scales are associated with
high specific SFR and hot dust.
AB - We present an analysis of the spectral energy distribution (SED) of the
galaxy ESO 184-G82, the host of the closest known long gamma-ray burst
(GRB) 980425 and its associated supernova (SN) 1998bw. We use our
observations obtained at the Australia Telescope Compact Array (the
third >3σ radio detection of a GRB host) as well as archival
infrared and ultraviolet (UV) observations to estimate its star
formation state. We find that ESO 184-G82 has a UV star formation rate
(SFR) and stellar mass consistent with the population of cosmological
GRB hosts and of local dwarf galaxies. However, it has a higher specific
SFR (per unit stellar mass) than luminous spiral galaxies. The mass of
ESO 184-G82 is dominated by an older stellar population in contrast to
the majority of GRB hosts. The Wolf-Rayet region ~800 pc from the SN
site experienced a starburst episode during which the majority of its
stellar population was built up. Unlike that of the entire galaxy, its
SED is similar to those of cosmological submillimeter/radio-bright GRB
hosts with hot dust content. These findings add to the picture that in
general, the environments of GRBs on 1-3 kpc scales are associated with
high specific SFR and hot dust.
U2 - 10.1088/0004-637X/693/1/347
DO - 10.1088/0004-637X/693/1/347
M3 - Article
SN - 1538-4357
VL - 693
SP - 347
EP - 354
JO - Astrophysical Journal
JF - Astrophysical Journal
ER -