GRB 010222: A Burst within a Starburst
Menten, K. M.; Price, P. A.; Harrison, F. A.; Galama, T. J.; Reichart, D. E.; Berger, E.; Bloom, J. S.; Djorgovski, S. G.; Frail, D. A.; Halpern, J.; Kulkarni, S. R.; Sari, R.; Walter, F.; Bertoldi, F.; Yost, S. A.; Peck, A. B.; Fox, D. W.; Moriarty-Schieven, G. H.; Shepherd, D. S.; Gerardy, C. L.
United States, Germany
Abstract
We present millimeter- and submillimeter-wavelength observations and near-infrared K-band imaging toward the bright gamma-ray burst GRB 010222. Over seven different epochs, a constant source was detected with an average flux density of 3.74+/-0.53 mJy at 350 GHz and 1.05+/-0.22 mJy at 250 GHz, giving a spectral index α=3.78+/-0.25 (where F~να). We rule out the possibility that this emission originated from the burst or its afterglow, and we conclude that it is due to a dusty, high-redshift starburst galaxy (SMM J14522+4301). We argue that the host galaxy of GRB 010222 is the most plausible counterpart of SMM J14522+4301, based in part on the centimeter detection of the host at the expected level. The optical/near-IR properties of the host galaxy of GRB 010222 suggest that it is a blue sub-L* galaxy, similar to other GRB host galaxies. This contrasts with the enormous far-infrared luminosity of this galaxy based on our submillimeter detection (LBol~4×1012Lsolar). We suggest that this GRB host galaxy has a very high star formation rate, SFR ~600 Msolar yr-1, most of which is unseen at optical wavelengths.