Suzaku Detection of Hard X-ray Emission in SGR 0501+4516 Short Burst Spectrum

摘要

Spectral studies of bursts from SGR 0501+4516 are presented using Suzaku data. We discovered hard X-ray emission in a summed spectrum of short bursts with low fluences, which has been found only in quiescent emission spectra so far. This result supports our idea that there are common emission mechanisms between the quiescent emission and the bursts of soft gamma repeaters and anomalous X-ray pulsars. The quiescent emission could consist of numerous micro-bursts. If this is the case, total released energy of small fluence (< 10~(-8) erg cm~(-2), 2-100 keV) bursts of a cumulative number-intensity distribution can be comparable to the energy released in the quiescent emission. We found that the total released energy can easily maintain the quiescent emission energy.