SIMBAD references

The blazar-type active galactic nuclei CTA 102 (QSO 2230+114) and 3C454.3 (QSO 2251+158), located about 7deg apart, were observed by the Compton Gamma Ray Observatory at four epochs in 1992. Both were detected by EGRET. The combined COMPTEL observations in the 10-30MeV energy range clearly indicate a source of MeV emission, which is likely due to a contribution from both quasars. These observations strongly suggest that the power-law spectra measured by EGRET above ∼50MeV flatten at lower MeV energies. A comparison with observations at other wavelengths shows that the power spectra of CTA 102 and 3C 454.3 peak at MeV energies. This behaviour appears to be a common feature of gamma-ray AGNs.