Looking for a possible faint blazar seen through the galactic disk in the field of HESSJ1356-645

A. CILLIS Y A. PICHEL

Tandil

Congreso; 56ava Reunion Anual de la Asociacion Argentina de Astronomia; 2013

IAFE

During its Galactic Plane Survey, HESS Collaboration detected the extended source HESSJ1356-645, localized at ~5 pc from the pulsar PSRJ 1357-6429 with an intrinsic Gaussian width of (0.2 +/- 0.02) deg. The most plausible scenario on the origin of the very high emission is an evolved and offset PWN powered by the mentioned pulsar. PSRJ1357-6429 is a young pulsar with a tau_c=7.3 kyr, a spin-down luminosity of 3.1 x 10^36 erg s^-1, and a period of 166 ms. It was discovery during the Parkes multibeam survey of the Galactic Plane. X-ray emission from the pulsar was detected for the first time using data from XMM-Newton and Chandra satellites, but without seeing pulsed emission from the source due to low statistic. Afterwards Fermi and XMM-Newton were able to detect pulsations. A possible optical counterpart of the pulsar was also reported recently, but the authors could not discard that this possible optical counterpart is not the pulsar, but a faint Active Galactic Nuclei (AGN). In the optical band the PWN was not detected. In order to unravel if the possible optical counterpart is or not a faint AGN, or at least of the blazar type, we applied the association method known as the WISE blazar Strip, based on the properties of Infrared colors using the Wide-Field Infrared Survey Explorer (WISE). According to this method we could not associate the possible optical counterpart to a blazar. Applying the same methodology, we also investigated if the sources seen in the field of HESSJ1356-645 by Chandra and XMM satellites could be blazars seen through the Galactic disk.