2001/05/31 by Z. Fodor, S. D. Katz, Fodor, Z. +1
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #astro-ph #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/0105347
4 pages, 1 figure, talk to be presented at the 27th International Cosmic Ray Conference, Hamburg, Germany, August 7-15, 2001
arxiv created 2001/05/31 · arxiv updated 2009/11/30
The clustering of ultrahigh energy (>1020 eV) cosmic rays (UHECR) suggests that they might be emitted by compact sources. Statistical analysis (Dubovsky et al., 2000) estimated the source density. We extend their analysis to give also the confidence intervals (CI) for the source density using a.) no assumptions on the relationship between clustered and unclustered events; b.) nontrivial distributions for the source luminosities and energies; c.) the energy dependence of the propagation. We also determine the probability that a proton created at a distance r with energy E arrives at earth above a threshold Ec. Using this function one can determine the observed spectrum just by one numerical integration for any injection spectrum. The observed 14 UHECR events above 1020 eV with one doublet gives for the source densities 180-165+2730⋅ 10-3 Mpc-3 (on the 68% confidence level).