CONSTRAINTS ON OBSCURED STAR FORMATION IN HOST GALAXIES OF GAMMA-RAY BURSTS

• 廿日出, 文洋

• Hashimoto, Tetsuya

• Ohta, Kouji

• Nakanishi, Kouichiro

• Tamura, Yoichi

• Kohno, Kotaro

抄録

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 2σ upper limits on star formation rates derived from the radio observations of the host galaxies are 23, 45, 27, and 26 M ☉ yr[–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.

収録刊行物

• The Astrophysical Journal

  The Astrophysical Journal 748 (2), 2012-03-13

  American Astronomical Society and IOP Publishing

キーワード

• cosmology: observations
• galaxies: high-redshift
• galaxies: ISM
• gamma-ray burst: individual (GRB 990705, GRB 021211, GRB 041006, GRB 051022)
• radio continuum: galaxies

詳細情報

• CRID: 1050564285685284352
• NII論文ID: 120004025594
• NII書誌ID: AA00553242
• ISSN: 0004637X
• HANDLE: 2433/155086
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles