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Abteilung Astronomie

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Preprint 01b/96

CGRO, Radio and Optical Observations of The Quasar NRAO 140

M. Maisack(1), R. Staubert(1), K. Otterbein(2), A. Witzel(2), S.J. Wagner(3), and A. Heines(3)

(1)Institut für Astronomie und Astrophysik, Astronomie, Universität Tübingen, Waldhäuser Str. 64, D-72076 Tübingen, Germany
(2)Max Planck Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany
(3)Landessternwarte Königstuhl, D-69117 Heidelberg, Germany

Contribution to the 3rd COMPTON Gamma Ray Observatory Symposium, München, Germany, June 12-14, 1995
accepted by Astronomy & Astrophysics Suppl.

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 (significance 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 3C 273.

Key words: Galaxies: active ; Gamma rays: observations

Paper (53k gzip'ed Postscript including figures)

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Jürgen Barnstedt (barnstedt AT astro.uni-tuebingen.de)
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