Astronomy and Astrophysics – Astrophysics
Scientific paper
Oct 1992
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992apj...398l..37c&link_type=abstract
Astrophysical Journal, Part 2 - Letters (ISSN 0004-637X), vol. 398, no. 1, p. L37-L40.
Astronomy and Astrophysics
Astrophysics
11
Electron-Positron Pairs, Seyfert Galaxies, X Ray Spectra, Active Galactic Nuclei, Astronomical Models, Astronomical Spectroscopy, Emission Spectra
Scientific paper
The recent observation by the detectors on board Granat of a spectral steepening above about 50 keV imposes a constraint on possible emission models for NGC 4151. This steepening, for example, is not well fitted by an exponential rollover characteristic of a purely thermal model, or by a Compton-downscattered power law. We find that this spectral behavior is consistent with that produced by a photon-starved nonthermal pair plasma with high compactness. This is the first quantitative test of the nonthermal pair plasma model against broad-band X-ray/gamma-ray observations. Above 200 keV or so, the nonthermal pair plasma model predicts an upturn in the spectrum, and a thermal annihilation feature around 511 keV. Such spectral behavior should be looked for with GRO.
Coppi Paolo S.
Zdziarski Andrzej A.
No associations
LandOfFree
Nonthermal electron-positron pairs and the break in the hard X-ray spectrum of NGC 4151 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Nonthermal electron-positron pairs and the break in the hard X-ray spectrum of NGC 4151, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Nonthermal electron-positron pairs and the break in the hard X-ray spectrum of NGC 4151 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1869690