Postlaunch Analysis ofSwift’s Gamma‐Ray Burst Detection Sensitivity

The dependence of Swift 's detection sensitivity on a burst's temporal and spectral properties shapes the detected burst population. Using simplified models of the detector hardware and the burst trigger system, I find that Swift is more sensitive to long, soft bursts than CGRO 's BATSE, a reference detector because of the large burst database it has accumulated. Swift has increased sensitivity in the parameter space region into which time dilation and spectral redshifting move high-redshift bursts.