The Swift Burst Analyser I: BAT and XRT spectral and flux evolution of Gamma Ray Bursts

Understand

Context: Gamma Ray Burst models predict the broadband spectral evolution and the temporal evolution of the energy flux.

• In contrast, standard data analysis tools and data repositories provide count-rate data, or use single flux conversion factors for all of the data, neglecting spectral evolution.
• Aims: To produce Swift BAT and XRT light curves in flux units, where the spectral evolution is accounted for.
• Methods: We have developed software to use the hardness ratio information to track spectral evolution of GRBs, and thus to convert the count-rate light curves from the BAT and XRT instruments on Swift into accurate, evolution-aware flux light curves.