HOW MANY ULTRA-HIGH ENERGY COSMIC RAYS COULD WE EXPECT FROM CENTAURUS A?

Journal Article · Sun Jul 01 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/753/1/40· OSTI ID:22036949

Fraija, N; Gonzalez, M M; Perez, M ^[1]; Marinelli, A ^[2]

---

1. Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Circuito Exterior, C.U., A. Postal 70-264, 04510 Mexico D.F. (Mexico)
2. Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Circuito Exterior, C.U., A. Postal 70-264, 04510 Mexico D.F. (Mexico)

The Pierre Auger Observatory has associated a few ultra-high energy cosmic rays (UHECRs) with the direction of Centaurus A. This source has been deeply studied in radio, infrared, X-ray, and {gamma}-rays (MeV-TeV) because it is the nearest radio-loud active galactic nucleus. Its spectral energy distribution or spectrum shows two main peaks, the low-energy peak, at an energy of 10{sup -2} eV, and the high-energy peak, at about 150 keV. There is also a faint very high energy (VHE; E {>=} 100 GeV) {gamma}-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/synchrotron self-Compton model, and the VHE emission with a hadronic model. We consider p{gamma} and pp interactions. For the p{gamma} interaction, we assume that the target photons are those produced at 150 keV in 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 p{gamma} interaction, we obtain an excessive luminosity in UHECRs (even exceeding the Eddington luminosity). However, when considering the pp interaction to describe the {gamma}-spectrum, the number of UHECRs obtained is in agreement with Pierre Auger observations. We also calculate the possible neutrino signal from pp interactions on a Km{sup 3} neutrino telescope using Monte Carlo simulations.

• OSTI ID: 22036949
• Journal Information: Astrophysical Journal, Vol. 753, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ASTROPHYSICS
COMPUTERIZED SIMULATION
COSMIC NEUTRINOS
COSMIC PHOTONS
ENERGY SPECTRA
GALAXY NUCLEI
GAMMA ASTRONOMY
GAMMA RADIATION
GEV RANGE
KEV RANGE
LUMINOSITY
MEV RANGE
PHOTON EMISSION
PHOTON-PROTON INTERACTIONS
PROTON-PROTON INTERACTIONS
RADIOASTRONOMY
RADIOWAVE RADIATION
RELATIVISTIC RANGE
TEV RANGE
X RADIATION