A Search for Host Galaxies of 24 Gamma-Ray Bursts

We report the results from observations of 24 gamma-ray burst (GRB) fields from 2005 and 2006 undertaken at the Danish 1.54 m telescope at ESO/La Silla. Photometry and positions for two previously unpublished host galaxy candidates (GRBs 050915 and 051021) are presented, as well as for eight other detected objects that are either known GRB hosts or candidate hosts. The candidates are suitable for spectroscopic follow-up in order to have their redshifts and other physical characteristics determined. In the cases where no likely host candidate is detected inside the refined Swift XRT error circle, we are still able to put interesting and rather deep limits on the host magnitude. On the basis of our detections and upper limits, we have performed simulations that suggest that the host galaxies are drawn from a fainter sample than those in previous (i.e., pre-Swift) studies.

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