CGRO, Radio and Optical Observations of the Quasar NRAO 140

M. Maisack; R. Staubert; K. Otterbein; A. Witzel; S. J. Wagner; A. Heines

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arXiv · astro-ph/9609002

CGRO, Radio and Optical Observations of the Quasar NRAO 140

M. Maisack·R. Staubert·K. Otterbein·A. Witzel·S. J. Wagner·A. Heines

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Abstract

We report on Compton Gamma Ray Observatory (CGRO), radio and optical observations of the radio-loud, superluminal quasar NRAO 140. The source is not detected (at a significance of greater than 3 sigma) by any of the CGRO instruments OSSE, Comptel and EGRET. Radio observations simultaneous to the OSSE observation and optical monitoring over three-monthly intervals show no signs of extraordinary behaviour when compared to previous observations. We demonstrate that the CGRO non-detections do not require a spectral break at hard X-rays, but can be explained by a steep spectrum in the MeV range comparable to that of 3C273.

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M. Maisack, R. Staubert, K. Otterbein, A. Witzel, S. J. Wagner, A. Heines. 1996-08-30. CGRO, Radio and Optical Observations of the Quasar NRAO 140. https://arxiv.org/abs/astro-ph/9609002

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