CONSTRAINTS ON OBSCURED STAR FORMATION IN HOST GALAXIES OF GAMMA-RAY BURSTS
- Department of Astronomy, Kyoto University, Kyoto 606-8502 (Japan)
- National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
- Institute of Astronomy, the University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015 (Japan)
We present the results of the 16 cm wave band continuum observations of four host galaxies of gamma-ray bursts (GRBs) 990705, 021211, 041006, and 051022 using the Australia Telescope Compact Array. Radio emission was not detected in any of the host galaxies. The 2{sigma} upper limits on star formation rates derived from the radio observations of the host galaxies are 23, 45, 27, and 26 M{sub Sun} yr{sup -1}, respectively, which are less than about 10 times those derived from UV/optical observations, suggesting that they have no significant dust-obscured star formation. GRBs 021211 and 051022 are known as the so-called dark GRBs and our results imply that dark GRBs do not always occur in galaxies enshrouded by dust. Because large dust extinction was not observed in the afterglow of GRB 021211, our result suggests the possibility that the cause of the dark GRB is the intrinsic faintness of the optical afterglow. On the other hand, by considering the high column density observed in the afterglow of GRB 051022, the likely cause of the dark GRB is the dust extinction in the line of sight of the GRB.
- OSTI ID:
- 22016109
- Journal Information:
- Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 748; ISSN ASJOAB; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
Similar Records
THE HOST GALAXIES OF SWIFT DARK GAMMA-RAY BURSTS: OBSERVATIONAL CONSTRAINTS ON HIGHLY OBSCURED AND VERY HIGH REDSHIFT GRBs
GRB 090417B AND ITS HOST GALAXY: A STEP TOWARD AN UNDERSTANDING OF OPTICALLY DARK GAMMA-RAY BURSTS