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The dark burst 010214 with BeppoSAX: possible variable absorption and jet X-ray emission

C. Guidorzi·F. Frontera·E. Montanari·L. Amati·L. A. Antonelli·J. J. M. in 't Zand·E. Costa·R. Farinelli·M. Feroci·J. Heise·N. Masetti·L. Nicastro·M. Orlandini·E. Palazzi·L. Piro
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Abstract

We report on the prompt and afterglow emission observations of the dark burst GRB010214 with BeppoSAX. The prompt emission shows possible evidence of variable absorption from N_H = 3.0^{+5.1}_{-2.0} x 10^23 cm-2 in the first 6 s of the event to a value consistent with the Galactic column density (N_H^(G) = 2.66 x 10^20 cm-2) in the GRB direction. An X-ray afterglow emission in the 2-10 keV energy band was detected with BeppoSAX, but an analogue search at lower wavelengths (optical, IR and radio) was unsuccessful. The X-ray afterglow spectrum is consistent with a power-law with Galactic absorption. The light curve shows a complex decay, if the tail of the prompt emission is assumed as the onset of the afterglow: if the origin of the afterglow is coincident with the GRB onset, a bump before ~ 3 x 10^4 s is inferred, while if the afterglow is assumed to start later, a steepening of the power-law light curve at t ~ 3 x 10^4 s is deduced. We discuss these results in the light of the current models of afterglows and the possible origin of the GRB darkness. Finally, we tentatively derive an estimate of the burst redshift.

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C. Guidorzi, F. Frontera, E. Montanari, L. Amati, L. A. Antonelli, J. J. M. in 't Zand, E. Costa, R. Farinelli, M. Feroci, J. Heise, N. Masetti, L. Nicastro, M. Orlandini, E. Palazzi, L. Piro. 2003-02-01. The dark burst 010214 with BeppoSAX: possible variable absorption and jet X-ray emission. https://doi.org/10.1051/0004-6361%3A20030143

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