GZK photons as UHECR above 10${}^{19}$ eV

Abstract

"GZK photons" are produced by extragalactic nucleons through the resonant photoproduction of pions. We present the expected range of the GZK photon fraction of UHECR, assuming a particular UHECR spectrum and primary nucleons, and compare it with the minimal photon fraction predicted by Top-Down models.

Comments: Talk given at TAUP2005, Sept. 10-14 2005, Zaragoza (Spain); 3 pages, 2 figures