I 型 X 射线暴多峰结构的研究进展 postprint

Abstract: Type-I (thermonuclear) X-ray bursts show a phenomenon of sudden increase in X-ray intensity, usually occurring in Low-Mass X-ray Binaries (LMXBs). Type-I X#2;ray bursts are considered as unstable ignition of accreted fuel on the surface of an accreting neutron star in the thermonuclear flash model. In a typical X-ray burst, the light curve shows a single-peaked profile with a fast rise and an exponential decay (FRED). With increasing detections of X-ray bursts, some unusual multi-peaked bursts appear. To date, the number of burster increases to 115, but only six sources have been reported with multi-peaked bursts. We find that multi-peaked bursts only appear in a few sources at different accretion rate. The peak flux in most of the multi-peaked bursts is lower than Eddington flux. Except the very rare triple-peaked bursts, most of the multi-peaked bursts are double-peaked bursts, and there is no regularity between the peaks’intensity in each double-peaked burst. The burst oscillation phenomenon has also no obvious regularity in double-peaked X-ray bursts. Finally, we summarize the theoretical models of multi-peaked bursts.