Naslov
Detection of VHE gamma-rays from HESS J0632+057 during the 2011 February X-ray outburst with the MAGIC telescopes

Autori
Aleksić, Jelena ; ... ; Dominis Prester, Dijana ; ... ; Ferenc, Daniel ; ... ; Godinović, Nikola ; ... ; Hrupec, Dario ; ... ; Lelas, Damir ; ... ; Puljak, Ivica ; ... ; Surić, Tihomir ; ... ; Šnidarić, Iva ; ... ; Terzić, Tomislav ; ... ; Zanin, R.

Izvornik
The Astrophysical journal (0004-637X) 754 (2012), 1; L10-1

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
binaries: general; gamma rays: general; stars: individual (MWC 148); X-rays: binaries; X-rays: individual (HESS J0632+057)

Sažetak
The very high energy (VHE) gamma-ray source HESS J0632+057 has recently been confirmed to be a gamma-ray binary. The optical counterpart is the Be star MWC 148, and a compact object of unknown nature orbits it every ~321 days with a high eccentricity of ~0.8. We monitored HESS J0632+057 with the stereoscopic MAGIC telescopes from 2010 October to 2011 March and detected significant VHE gamma-ray emission during 2011 February, when the system exhibited an X-ray outburst. We find no gamma-ray signal in the other observation periods when the system did not show increased X-ray flux. Thus, HESS J0632+057 exhibits gamma-ray variability on timescales of the order of one to two months possibly linked to the X-ray outburst that takes place about 100 days after the periastron passage. Furthermore, our measurements provide for the first time the gamma-ray spectrum down to about 140 GeV and indicate no turnover of the spectrum at low energies. We compare the properties of HESS J0632+057 with the similar gamma-ray binary LS I +61 303 and discuss the possible origin of the multi-wavelength emission of the source.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA