BATSE burst location accuracy and constraints on the fraction of repeating GRB sources

摘要

We use a one parameter model for GRB source repetition to investigate the ability of BATSE to detect source repetition and to place constraints on the fraction of repeating sources. From Monte Carlo simulations we find that the current uncertainty in BATSE burst locations severely limits our ability to confidently detect source repetition from distributions containing fewer than 10 (minus)15% repeaters. A fit of our repetition model to 260 BATSE catalog bursts yields a best-fit repeating fraction of f(sub r) = 21% with a 90% confidence region ranging from 5.5 to 32.5%. By modifying the size of the measurement errors in our simulations we show that the location and width of the confidence region depends sensitively on the burst location errors. With BATSEs present location accuracy analysis of larger samples of bursts will not appreciably improve the constraint on the repeating fraction.