Discovery of VHE gamma-rays from the high-frequency-peaked BL Lac object RGB J0152+017

Understand

Aims: The BL Lac object RGB J0152+017 (z=0.080) was predicted to be a very high-energy (VHE; > 100 GeV) gamma-ray source, due to its high X-ray and radio fluxes.

• Our aim is to understand the radiative processes by investigating the observed emission and its production mechanism using the High Energy Stereoscopic System (H.E.S.S.) experiment.
• Methods: We report recent observations of the BL Lac source RGB J0152+017 made in late October and November 2007 with the H.E.S.S.
• array consisting of four imaging atmospheric Cherenkov telescopes.