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arXiv · astro-ph/0304477

INTEGRAL and XMM-Newton observations of the weak GRB 030227

S. Mereghetti·D. Gotz·A. Tiengo·V. Beckmann·J. Borkowski·T. J. -L. Courvoisier·A. von Kienlin·V. Schoenfelder·J. P. Roques·L. Bouchet·P. Ubertini·A. Castro-Tirado·F. Lebrun·J. Paul·N. Lund·M. Mas Hesse·W. Hermsen·P. den Hartog·C. Winkler
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Abstract

We present INTEGRAL and XMM-Newton observations of the prompt gamma-ray emission and the X-ray afterglow of GRB030227, the first GRB for which the quick localization obtained with the INTEGRAL Burst Alert System (IBAS) has led to the discovery of X-ray and optical afterglows. GRB030227 had a duration of about 20 s and a peak flux of 1.1 photons cm^-2 s^-1 in the 20-200 keV energy range. The time averaged spectrum can be fit by a single power law with photon index about 2 and we find some evidence for a hard to soft spectral evolution. The X-ray afterglow has been detected starting only 8 hours after the prompt emission, with a 0.2-10 keV flux decreasing as t^-1 from 1.3x10e-12 to 5x10e-13 erg cm^-2 s^-1. The afterglow spectrum is well described by a power law with photon index 1.94+/-0.05 modified by a redshifted neutral absorber with column density of several 10e22 cm^-2. A possible emission line at 1.67 keV could be due to Fe for a redshift z=3, consistent with the value inferred from the absorption.

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S. Mereghetti, D. Gotz, A. Tiengo, V. Beckmann, J. Borkowski, T. J. -L. Courvoisier, A. von Kienlin, V. Schoenfelder, J. P. Roques, L. Bouchet, P. Ubertini, A. Castro-Tirado, F. Lebrun, J. Paul, N. Lund, M. Mas Hesse, W. Hermsen, P. den Hartog, C. Winkler. 2003-04-26. INTEGRAL and XMM-Newton observations of the weak GRB 030227. https://doi.org/10.1086/376853

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