Discovery of a redshifted Iron K-line in the X-ray afterglow of GRB 000214

L. A. Antonelli; L. Piro; M. Vietri; E. Costa; P. Soffitta; M. Feroci; L. Amati; F. Frontera; E. Pian; J. J. M. in 't Zand; J. Heise; E. Kuulkers; L. Nicastro; R. C. Butler; L. Stella; G. C. Perola

doi:10.1086/317328

arXiv · astro-ph/0010221

Discovery of a redshifted Iron K-line in the X-ray afterglow of GRB 000214

L. A. Antonelli·L. Piro·M. Vietri·E. Costa·P. Soffitta·M. Feroci·L. Amati·F. Frontera·E. Pian·J. J. M. in 't Zand·J. Heise·E. Kuulkers·L. Nicastro·R. C. Butler·L. Stella·G. C. Perola

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Abstract

We report the detection (3 sigma significance level) of a strong iron emission line in the X-ray spectrum of the afterglow of GRB 000214 (``Valentine's Day Burst'') observed by BeppoSAX. An emission line feature was observed with a centroid energy of 4.7+/-0.2 keV which, if interpreted as K-alpha emission from hydrogen-like iron, corresponds to a redshift of z=0.47. The observed intensity (EW ~2 keV) and duration (tens of hours) of the line give information on the distance, from the burst region, of the emitting material (R>3x10^15 cm) and its mass (M>1.4 solar mass). These results are not easily reconciled with the binary merger and hypernova models for gamma ray bursts.

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L. A. Antonelli, L. Piro, M. Vietri, E. Costa, P. Soffitta, M. Feroci, L. Amati, F. Frontera, E. Pian, J. J. M. in 't Zand, J. Heise, E. Kuulkers, L. Nicastro, R. C. Butler, L. Stella, G. C. Perola. 2000-10-11. Discovery of a redshifted Iron K-line in the X-ray afterglow of GRB 000214. https://doi.org/10.1086/317328

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