Development of A New Background Reduction Method for WXM/HETE-2 and Its Application for Bright GRB Spectra

摘要

HETE-2 detected gamma-ray bursts (GRBs) since its launch on 9 October 2000. For spectral analyses using data of WXM on-board HETE-2, background spectra are conventionally obtained with time regions before and/or after prompt emission. In some cases, the background spectra change during the prompt emission and/or the downlink trouble causes a loss of data around the prompt emission. If this is the case, the problem seems to lie in the fact that the conventional method cannot obtain correct background spectra. To make more appropriate background spectra, we develop a new analysis method using mask patterns of the WXM. The background spectra are estimated with shaded regions by the WXM mask pattern using the prompt emission data. Our new method might obtain a reliable result for a spectrum of GRB 030329. In this paper, we introduce our new analysis method and show a preliminary spectral result.