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تسجيل مستخدم جديدCOMPTEL Observation of the Flaring Quasar PKS0528+134
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S. Zhang
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With a direct demodulation method, we have reanalyzed the data from COMPTEL/CGRO observation of PKS0528+134 during the 1993 March flare in gamma-rays. Our results show that during the flare gamma-rays were detected at a level approximately 2.4-3.8 times greater than the observed intensity in two earlier COMPTEL observations VP 0 and VP 1 in the energy range 3 MeV to 30 MeV. The 3-30 MeV time variability of the flux follows well the trend as observed by EGRET/CGRO at higher energies. No convincing excess can be found around the position of PKS0528+134 in the energy range 0.75 MeV to 3 MeV, which indicates a spectral break around 3 MeV. The detections and non-detections in the four standard COMPTEL energy bands are consistent with the earlier reports given by Collmar et al., while the feature that gamma-rays of the quasar still kept on flaring at energies down to 3 MeV is clearly found.
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The COMPTEL observations of the blazar-type quasar PKS 0528+134 in the energy range 0.75 MeV to 30 MeV carried out between April 1991 and September 1994 have been analyzed. During the first two years PKS 0528+134 was most significantly detected at en
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