Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2002-04-30
Phys.Rev. D74 (2006) 043005
Physics
High Energy Physics
High Energy Physics - Phenomenology
Revised version as published in Phys.Rev. D47 (2006) 043005 with a small addition
Scientific paper
10.1103/PhysRevD.74.043005
We argue that an astrophysical solution to UHECR problem is viable. The pectral features of extragalactic protons interacting with CMB are calculated in model-independent way. Using the power-law generation spectrum $\propto E^{-\gamma_g}$ as the only assumption, we analyze four features of the proton spectrum: the GZK cutoff, dip, bump and the second dip. We found the dip, induced by electron-positron production on CMB, as the most robust feature, existing in energy range $1\times 10^{18} - 4\times 10^{19}$ eV. Its shape is stable relative to various phenomena included in calculations. The dip is well confirmed by observations of AGASA, HiRes, Fly's Eye and Yakutsk detectors. The best fit is reached at $\gamma_g =2.7$, with the allowed range 2.55 - 2.75. The dip is used for energy calibration of the detectors. After the energy calibration the fluxes and spectra of all three detectors agree perfectly, with discrepancy between AGASA and HiRes at $E> 1\times 10^{20}$ eV being not statistically significant. The agreement of the dip with observations should be considered as confirmation of UHE proton interaction with CMB. The dip has two flattenings. The high energy flattening at $E \approx 1\times 10^{19}$ eV automatically explains ankle. The low-energy flattening at $E \approx 1\times 10^{18}$ eV provides the transition to galactic cosmic rays. This transition is studied quantitatively. The UHECR sources, AGN and GRBs, are studied in a model-dependent way, and acceleration is discussed. Based on the agreement of the dip with existing data, we make the robust prediction for the spectrum at $1\times 10^{18} - 1\times 10^{20}$ eV to be measured in the nearest future by Auger detector.
Berezinsky Veniamin
Gazizov A. Z.
Grigorieva S. I.
No associations
LandOfFree
On astrophysical solution to ultra high energy cosmic rays 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 On astrophysical solution to ultra high energy cosmic rays, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On astrophysical solution to ultra high energy cosmic rays will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-626314