Integral and Xmm-newton Observations of the Weak Grb 030227
نویسندگان
چکیده
We present INTEGRAL and XMM-Newton observations of the prompt γ-ray emission and the X–ray afterglow of GRB 030227 , 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. GRB 030227 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 ∼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 1.3×10 −12 to 5×10 −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 10 22 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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