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 .

We report recent observations of this source made in late October and November 2007 with the H.E.S.S .
array consisting of four imaging atmospheric Čerenkov telescopes .
Contemporaneous observations were made in X-rays with the Swift and RXTE satellites , in the optical band with the ATOM telescope , and in the radio band with the Nançay Radio Telescope .

As a result , RGB J0152 + 017 is discovered as a source of VHE \gamma -rays by H.E.S.S .
A signal of 173 \gamma -ray photons corresponding to a statistical significance of 6.6 \sigma was found in the data .
The energy spectrum of the source can be described by a powerlaw with a spectral index of \Gamma = 2.95 \pm 0.36 _ { \mathrm { stat } } \pm 0.20 _ { \mathrm { syst } } .
The integral flux above 300 GeV corresponds to \sim 2 % of the flux of the Crab nebula .
The source spectral energy distribution ( SED ) can be described using a two-component ( extended jet and blob in jet ) non-thermal synchrotron self-Compton ( SSC ) leptonic model , plus a thermal host galaxy component .
The parameters that are found are very close to those found for TeV blazars in similar SSC studies .

The location of its synchrotron peak , as derived from the SED in Swift data , allows clear classification as a high-frequency-peaked BL Lac ( HBL ) .