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The star-formation rate in the host of GRB 990712

P. M. Vreeswijk·R. P. Fender·M. A. Garrett·S. J. Tingay·A. S. Fruchter·L. Kaper
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Abstract

We have observed the host galaxy of GRB 990712 at 1.4 GHz with the Australia Telescope Compact Array, to obtain an estimate of its total star-formation rate. We do not detect a source at the position of the host. The 2 sigma upper limit of 70 microJy implies that the total star-formation rate is lower than 100 Msun/yr, using conservative values for the spectral index and cosmological parameters. This upper limit is in stark contrast with recent reports of radio/submillimeter-determined star-formation rates of roughly 500 Msun/yr for two other GRB host galaxies. Our observations present the deepest radio-determined star-formation rate limit on a GRB host galaxy yet, and show that also from the unobscured radio point-of-view, not every GRB host galaxy is a vigorous starburst.

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P. M. Vreeswijk, R. P. Fender, M. A. Garrett, S. J. Tingay, A. S. Fruchter, L. Kaper. 2001-10-25. The star-formation rate in the host of GRB 990712. https://doi.org/10.1051/0004-6361%3A20011484

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