The Swift Mission

Abstract

The Swift Gamma-ray Burst Explorer mission, launched on 2004 November 20, is a multiwavelength observatory for gamma-ray burst (GRB) astronomy. The satellite carries three instruments: a new-generation wide-field gamma-ray (15–150 keV) detector that detects bursts, calculates 1–4 arcmin positions, and triggers autonomous spacecraft slews; a narrow-field X-ray telescope that gives 5 arcsec positions and performs spectroscopy in the 0.2 to 10 keV band; and a narrow-field UV/optical telescope that operates in the 170–600 nm band and provides 0.3 arcsec positions and optical finding charts. In the first 8 months of the mission (until the end of July 2005), Swift detected 54 GRBs performing detailed X-ray and UV/optical afterglow observations spanning timescales from 1 minute to several days after the burst. Swift has already collected a rich trove of early X-ray afterglow data and some interesting features are emerging. In particular early afterglow signatures reveal valuable and unprecedented information about GRBs, including the prompt emission – afterglow transition, GRB emission site, central engine activity, forward-reverse shock physics, and the GRB immediate environment.