COMPTEL Observations of 3C 279 during the first 4 Years of the CGRO-Mission

W. Collmar; J. J. Blom; K. Bennett; H. Bloemen; W. Hermsen; J. Ryan; V. Schoenfelder; J. G. Stacy; O. R. Williams

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arXiv · astro-ph/9711345

COMPTEL Observations of 3C 279 during the first 4 Years of the CGRO-Mission

W. Collmar·J. J. Blom·K. Bennett·H. Bloemen·W. Hermsen·J. Ryan·V. Schoenfelder·J. G. Stacy·O. R. Williams

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Abstract

The COMPTEL experiment aboard the Compton Gamma-Ray Observatory (CGRO) has observed the gamma-ray blazar 3C 279 several times between April 1991 and September 1995. This paper reports on a consistent analysis of these observations using the most recent COMPTEL data analysis tools. Detections and non-detections of 3C 279 along the CGRO-mission indicate a time-variable MeV-flux. Spectral variability is indicated as well, however can not be significantly proven by spectral fitting. The average MeV-spectrum of 3C 279, as measured by COMPTEL over the four-year period, is consistent with a photon power-law slope of about -1.9. This spectrum smoothly connects to the simultaneous 30 MeV to 10 GeV spectrum obtained from an analysis of the combined EGRET observations. No spectral break is required to fit the time-averaged MeV- to GeV-spectrum of 3C 279.

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BibTeX RIS

W. Collmar, J. J. Blom, K. Bennett, H. Bloemen, W. Hermsen, J. Ryan, V. Schoenfelder, J. G. Stacy, O. R. Williams. 1997-11-28. COMPTEL Observations of 3C 279 during the first 4 Years of the CGRO-Mission. https://arxiv.org/abs/astro-ph/9711345

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