Gamma Ray Physics with GLAST

The Gamma-ray Large Area Telescope (GLAST) is a high energy (5 KeV - 300 GeV) γ-ray astronomy mission planned for launch in September 2007. The study of detected spectra of γ-rays is fundamental for the understanding of acceleration, emission, absorption and propagation mechanism of very high energy particles. This energy region has not been covered by any other experiment after the end of EGRET, which has performed the first survey of the full gamma-ray sky. Compared to previous instruments the telescope has a greatly improved sensitivity of (above 100 MeV for a 2 years all sky survey) and ability to localize γ-ray point sources. In this paper topics of interest for GLAST, like active galactic nuclei, unidentified sources, gamma ray bursts and study of the cosmic ray acceleration will be reviewed, as well as the status of the Large Area Telescope (LAT).