TeV gamma rays from photodisintegration and daughter deexcitation of cosmic-ray nuclei.
It is commonly assumed that high-energy gamma rays are made via either purely electromagnetic processes or the hadronic process of pion production, followed by decay. We investigate astrophysical contexts where a third process (A*) would dominate: namely, the photodisintegration of highly boosted nuclei followed by daughter deexcitation. Starburst regions such as Cygnus OB2 appear to be promising sites for TeV gamma-ray emission via this mechanism. A unique feature of the A* process is a sharp flattening of the energy spectrum below approximately 10 TeV/(T/eV) for gamma-ray emission from a thermal region of temperature T. The A* mechanism described herein offers an important contribution to gamma-ray astronomy in the era of intense observational activity.
Anchordoqui
Luis A
LA
Department of Physics, University of Wisconsin-Milwaukee, P.O. Box 413, Milwaukee, Wisconsin 53201, USA.
Beacom
John F
JF
Goldberg
Haim
H
Palomares-Ruiz
Sergio
S
Weiler
Thomas J
TJ