Konus-Wind Observations of the New Soft Gamma-Ray Repeater SGR 0501+4516

• Published in: Astrophysical journal. Letters 2009-06, Vol.698 (2), p.L82-L85
• Main Authors: Aptekar, R. L, Cline, T. L, Frederiks, D. D, Golenetskii, S. V, Mazets, E. P, Pal'shin, V. D
• Format: Article
• Language: English
• ISSN: 1538-4357; 0004-637X; 2041-8205; 1538-4357
• DOI: 10.1088/0004-637X/698/2/L82

In 2008 August, the new soft gamma-ray repeater SGR 0501+4516 was discovered by Swift. The source was soon confirmed by several groups in space- and ground-based multi-wavelength observations. In this Letter, we report the analysis of five short bursts from the recently discovered soft gamma-ray repeater (SGR), detected with the Konus-Wind gamma-ray burst spectrometer. Properties of the time histories of the observed events, as well as results of multichannel spectral analysis, both in the 20-300 keV energy range, show, that the source exhibits itself as a typical SGR. The bursts durations are 0.75 s and their spectra above 20 keV can be fitted by an optically thin thermal bremsstrahlung (OTTB) model with kT OTTB of 20-40 keV. The spectral evolution is observed, which resembles the SGR 1627-41 bursts, where a strong hardness-intensity correlation was noticed in the earlier Konus-Wind observations. The peak energy fluxes of all five events are comparable to the highest of those for known SGRs, so a less distant source is implied, consistent with the determined Galactic anticenter direction. Supposing the young supernova remnant HB9 (at the distance of 1.5 kpc) as a natal environment of the source, the peak luminosities of the bursts are estimated to be (2-5)X1040 erg s-1. The values of the total energy release, given the same assumptions, amount to (0.6-6)X1039 erg. These estimations of both parameters are typical for short SGR bursts.