Author/Authors :
Shaw، S. E. نويسنده , , Lund، N. نويسنده , , Gotz، D. نويسنده , , Mereghetti، S. نويسنده , , Hudec، R. نويسنده , , Courvoisier، T. J.-L. نويسنده , , Beckmann، V. نويسنده , , Kienlin، A. von نويسنده , , Hroch، F. نويسنده , , Borkowski، J. نويسنده , , Wigger، C. نويسنده ,
Abstract :
We present multiwavelength observations of a gamma-ray burst detected by INTEGRAL (GRB 030227) between 5.3 hours and ~1.7 days after the event. Here we report the discovery of a dim optical afterglow (OA) that would not have been detected by many previous searches due to its faintess (R~ 23). This OA was seen to decline following a power law decay with index (alpha)(R)=-0.95 (plus-minus) 0.16. The spectral index (beta)opt/NIR yielded 1.25 (plus-minus) 0.14.These values may be explained by a relativistic expansion of a fireball (with p = 2.0) in the cooling regime. We also find evidence for inverse Compton scattering in X-rays.
