Konus-wind Observations of the New Soft Gamma-ray Repeater Sgr 0501+4516

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 spaceand ground-based multi-wavelength observations. In this letter we report the analysis of five short bursts from the recently discovered SGR, detected with Konus-Wind gamma-ray burst spectrometer. Properties of the time histories of the observed events, as well as results of multi-channel 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 optically-thin thermal bremsstrahlung (OTTB) model with kTOTTB 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 highest those for known SGRs, so a less distant source is implied, consistent with the determined Galactic anti-center 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)×10 erg s. The values of the total energy release, given the same assumptions, amount to (0.6–6)×10 erg. These estimations of both parameters are typical for short SGR bursts. Subject headings: gamma rays: bursts gamma rays: observations pulsars: individual (SGR 0501+4516) stars: neutron