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Near-infrared detection and optical follow-up of the GRB990705 afterglow

N. Masetti
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Abstract

Optical and near-infrared observations of the GRB990705 error box were carried out with ESO telescopes at La Silla and Paranal in Chile and with the NOAO SPIREX 0.6-meter telescope in Antarctica. We detected the counterpart of this GRB in the near-infrared H band and optical V band. The power-law decline of the near-infrared lightcurve is rather steep with a decay index alpha ~ 1.7 in the first hours, and a possible steepening after one day. Broadband spectral analysis of the optical/near-infrared afterglow suggests that this GRB took place in a high density environment. A deep optical image obtained at Antu (VLT-UT1) about 5 days after the GRB trigger shows at the position of the transient an extended object which might be the host galaxy of GRB990705.

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N. Masetti. 1999-12-20. Near-infrared detection and optical follow-up of the GRB990705 afterglow. https://arxiv.org/abs/astro-ph/9912423

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