NAM logo, by David Le Conte

SWIFT: a new gamma-ray burst mission

David Fletcher-Holmes and Alan Wells (Leicester)

After decades of relatively slow progress, the discovery of afterglows from gamma-ray bursts has revolutionised our understanding of these enigmatic events. We now know that they are produced at cosmological distances, and involve the most powerful and highly relativistic explosions known, and that they exhibit afterglows that cascade down in energy from gamma-rays to the radio. The Swift MIDEX is a rapid-response, multi-wavelength observatory that will exploit the newly discovered afterglow characteristics of gamma-ray bursts to perform a high sensitivity study of ca. 1000 bursts.

Swift will routinely locate GRBs to within a few arcminutes, seconds after their onset, using a gamma-ray Burst Alert Telescope (BAT). The satellite will then perform a rapid slew, bringing narrow field co-aligned X-ray and UV/optical telescopes to bear on the target. These telescopes will provide positions accurate to a few arcseconds only a minute or so after the initial trigger and will observe the evolving afterglow in the optical, UV and X-ray regimes. The multi-frequency properties of these afterglows as measured by SWIFT will reveal how the blast wave evolves and interacts with its surroundings. The large numbers of bursts detected will allow us to identify different classes of bursts, and to determine the physical processes responsible. In addition, Swift will enable us to use the bursts as transient probes of the early Universe. SWIFT GRB parameters distributed through the GRB Co-ordinates Network (GCN), will support rapid, world-wide, multi-wavelength, follow-up programmes using ground based and space based optical and radio facilities.

Maintained by Ian Howarth