Non-variable cosmologically distant gamma-ray emitters as an imprint of propagation of ultra-high-energy protons

摘要: The acceleration sites of ultra-high-energy (UHE) protons can be traced by the footprint left these particles when they propagate through cosmic microwave background (CMB) radiation. Secondary electrons produced in extended region several tens Mpc emit their energy via synchrotron radiation predominantly initial direction parent protons. This forms a non-variable and compact (almost point-like) source high-energy gamma rays. importance this effect is increased for cosmologically distant objects; because severe losses, UHE cannot reach us even case extremely weak intergalactic magnetic fields. Moreover, at high redshifts conversion from to secondary becomes significantly more effective denser energetic CMB past. increases chances rays We discuss budget redshift dependence transfer efficiency angular spectral distributions gamma- X-ray bands are calculated discussed context detectability Fermi LAT Chandra observatories.