The Pierre Auger Observatory has associated a few ultra high energy cosmic
rays with the direction of Centaurus A. This source has been deeply studied in
radio, infrared, X-ray and γ-rays (MeV-TeV) because it is the nearest
radio-loud active galactic nuclei.
Its spectral energy distribution or spectrum shows two main peaks, the low
energy peak, at an energy of 10−2 eV, and the high energy peak, at about
150 keV.
There is also a faint very high energy (E ≥ 100 GeV) γ-ray
emission fully detected by the High Energy Stereoscopic System experiment. In
this work we describe the entire spectrum, the two main peaks with a
Synchrotron/Self-Synchrotron Compton model and, the Very High Energy emission
with a hadronic model. We consider pγ and pp interactions. For the
pγ interaction, we assume that the target photons are those produced at
150 keV in the leptonic processes. On the other hand, for the pp interaction we
consider as targets the thermal particle densities in the lobes. Requiring a
satisfactory description of the spectra at very high energies with pγ
interaction we obtain an excessive luminosity in ultra high energy cosmic rays
(even exceeding the Eddington luminosity). However, when considering pp
interaction to describe the γ-spectrum, the obtained number of ultra
high energy cosmic rays are in agreement with Pierre Auger observations.
Moreover, we calculate the possible neutrino signal from pp interactions on a
Km3 neutrino telescope using Monte Carlo simulations.Comment: Accepted in Ap