Fermi Gamma-ray Space Telescope

The distribution of GRB spectral lags

V. Heussaff
J. L. Atteia, J. P. Dezalay, R. Mochkovitch

Abstract:

Spectral lags have been proposed to standardize GRBs through the Lag-Liso relation. However, the physical origin of spectral lags is not completly understood. With a sample of Swift GRBs, we study the distribution of intrinsic spectral lags (measured in the restframe of the source) and the existence of selection effects that could affect lag measurement and the Lag-Liso relation. We highlight the importance of having a broad energy coverage. This coverage could be provided by Fermi/GBM for a better understanding of spectral lags.