COMPTEL upper limits for Seyfert galaxies

Authors

M Maisack, University of Tubingen
W Collmar, Max-Planck-Institut für extraterrestriche Physik
G G. Lichti, Max-Planck-Institut für extraterrestrische Physik
V Schonfelder, Max-Planck-Institut für extraterrestrische PhysikFollow
H Steinle, Max-Planck-Institut für extraterrestriche PhysikFollow
H Bloemen, Space Research Organization of the Netherlands
W Hermsen, Space Research Organization of the Netherlands (SRON)
Mark L. McConnell, University of New Hampshire - Main CampusFollow
G Stacy, University of New Hampshire - Main CampusFollow
P Barr, ESTEC
O R. Williams, ESTECFollow

Abstract

The gamma‐ray emission of Seyfert galaxies has fallen far short of pre‐GRO expectations. No single object of this class has been detected by either COMPTEL or EGRET, and OSSE has detected only a fraction of the Seyferts expected. To derive a more stringent upper limit to the emission from these objects in the energy ranges 0.75 to 1 and 1 to 3 MeV, we have summed a large number of COMPTEL observations acquired during Phase 1 of the GRO mission. From a total of 47 observations of 23 individual X‐ray selected Seyfert galaxies, we derive preliminary upper limits of 8×10⁻⁸ photons/(cm² s keV) in the 0.75‐1 MeV band and 1×10⁻⁸ photons/(cm² s keV) in the 1‐3 MeV band.

Department

Space Science Center, Physics

Publication Date

1994

Journal Title

AIP Conference Proceedings

Publisher

AIP Publishing

Digital Object Identifier (DOI)

10.1063/1.45652

Document Type

Conference Proceeding

Recommended Citation

COMPTEL upper limits for Seyfert galaxies Maisack, M. and Collmar, W. and Lichti, G. G. and Schönfelder, V. and Steinle, H. and Bloemen, H. and Hermsen, W. and McConnell, M. and Stacy, G. and Barr, P. and Williams, O. R., AIP Conference Proceedings, 304, 556-560 (1994), DOI:http://dx.doi.org/10.1063/1.45652

Rights

© 1994 American Institute of Physics