Sarira Sahu, Bing Zhang, Nissim Fraija
Centaurus A (Cen A) is the nearest radio-loud AGN and is detected from radio
to very high energy gamma-rays. Its nuclear spectral energy distribution (SED)
shows a double-peak feature, which is well explained by the leptonic
synchrotron + synchrotron self-Compton model. This model however cannot account
for the observed high energy photons in the TeV range, which display a distinct
component. Here we show that ~ TeV photons can be well interpreted as the
neutral pion decay products from p-gamma interactions of Fermi accelerated high
energy protons in the jet with the seed photons around the second SED peak at
~170 keV. Extrapolating the inferred proton spectrum to high energies, we find
that this same model is consistent with the detection of 2 ultra-high-energy
cosmic ray events detected by Pierre Auger Observatory from the direction of
Cen A. We also estimate the GeV neutrino flux from the same process, and find
that it is too faint to be detected by current high-energy neutrino detectors.
View original:
http://arxiv.org/abs/1201.4191
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