Investigating the EGRET-radio galaxies link with INTEGRAL: The case of 3EG J1621+8203 and NGC 6251
Guainazzi, M.; Grenier, I. A.; Grandi, P.; Chaty, S.; Rodriguez, J.; Foschini, L.; Di Cocco, G.; Malaguti, G.; Chiaberge, M.; Kuiper, L.; Hermsen, W.; Corbel, S.; Palumbo, G. G. C.
Italy, France, Spain, Netherlands, Switzerland
Abstract
The analysis of an INTEGRAL AO2 observation of the error contours of the EGRET source 3EG J1621+8203 is presented. The only source found inside the error contours for energies between 20 and 30 keV at 5σ detection significance is the FR I radio galaxy NGC 6251. This supports the identification of NGC 6251 with 3EG J1621+8203. The observed flux is higher and softer than observed in the past, but consistent with a variable blazar-like spectral energy distribution.
Based on observations with INTEGRAL, an ESA mission with instruments and science data center funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Switzerland, Spain), Czech Republic and Poland, and with the participation of Russia and the USA.