Fermi Gamma-ray Space Telescope

Is the plateau emission also a feature of high energy GRBs?

Maria Dainotti
Nicola Omodei, Vahe' Petrosian, Shigehiro Nagataki

Abstract:

Fermi-LAT observations provide the unprecedented opportunity to study the broadband afterglow properties of the GRBs, in particular the plateau in the light curve as seen in Swift observations. The sample of >35 GRBs with LAT observation, with coverage up to 300 GeV, when combined with Swift data provide a broad band exploration of these aspects of GRBs which can provide new and exciting clues into GRB emission mechanisms. We propose to analyze the GRB light curves observed both by the LAT and Swift (BAT+XRT) in order to investigate the existence of the plateau emission at high energies, determine its characteristics and use the result to constrain theoretical models. This investigation is carried out through a comparison with the results from investigation of much larger (>350) sample of Swift GRB light curves showing plateau. We explore in the LAT band the existence of plateau luminosity-duration anti-correlation we have shown to be present in the Swift data as a further model discriminator and its implication of cosmological studies of the early universe.