VLT identification of the optical afterglow of the gamma-ray burst GRB 000131 at z=4.50

TY - JOUR

T1 - VLT identification of the optical afterglow of the gamma-ray burst GRB 000131 at z=4.50

AU - Andersen, M. I.

AU - Hjorth, J.

AU - Pedersen, H.

AU - Jensen, B. L.

AU - Hunt, L. K.

AU - Gorosabel, J.

AU - Moller, P.

AU - Fynbo, J.

AU - Kippen, R. M.

AU - Thomsen, B.

AU - Olsen, L. F.

AU - Christensen, L.

AU - Vestergaard, Marianne

AU - Masetti, N.

AU - Palazzi, E.

AU - Hurley, K.

AU - Cline, T.

AU - Kaper, L.

AU - Jaunsen, A. O.

PY - 2000/10/17

Y1 - 2000/10/17

N2 - We report the discovery of the gamma-ray burst GRB 000131 and its optical afterglow. The optical identification was made with the VLT 84 hours after the burst following a BATSE detection and an Inter Planetary Network localization. GRB 000131 was a bright, long-duration GRB, with an apparent precursor signal 62 s prior to trigger. The afterglow was detected in ESO VLT, NTT, and DK1.54m follow-up observations. Broad-band and spectroscopic observations of the spectral energy distribution reveals a sharp break at optical wavelengths which is interpreted as a Ly-alpha absorption edge at 6700 A. This places GRB 000131 at a redshift of 4.500 +/- 0.015. The inferred isotropic energy release in gamma rays alone was approximately 10^54 erg (depending on the assumed cosmology). The rapid power-law decay of the afterglow (index alpha=2.25, similar to bursts with a prior break in the lightcurve), however, indicates collimated outflow, which relaxes the energy requirements by a factor of

AB - We report the discovery of the gamma-ray burst GRB 000131 and its optical afterglow. The optical identification was made with the VLT 84 hours after the burst following a BATSE detection and an Inter Planetary Network localization. GRB 000131 was a bright, long-duration GRB, with an apparent precursor signal 62 s prior to trigger. The afterglow was detected in ESO VLT, NTT, and DK1.54m follow-up observations. Broad-band and spectroscopic observations of the spectral energy distribution reveals a sharp break at optical wavelengths which is interpreted as a Ly-alpha absorption edge at 6700 A. This places GRB 000131 at a redshift of 4.500 +/- 0.015. The inferred isotropic energy release in gamma rays alone was approximately 10^54 erg (depending on the assumed cosmology). The rapid power-law decay of the afterglow (index alpha=2.25, similar to bursts with a prior break in the lightcurve), however, indicates collimated outflow, which relaxes the energy requirements by a factor of

KW - astro-ph

M3 - Journal article

SN - 0004-6361

VL - 364

SP - L54-L61

JO - Astronomy and Astrophysics Supplement Series

JF - Astronomy and Astrophysics Supplement Series

ER -