2002/09/22 by John P. Ralston, Ralston, John P., S. Razzaque +4 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #Astrophysics (astro-ph) #Copper Interconnects and Reliability #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Muon and positron interactions and applications #Semiconductor materials and devices #astro-ph #hep-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0209455
4 pages, 1 figure
arxiv created 2002/09/22 · openalex publication_date 2002/09/22 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Cosmic rays in the regime of 1019-1020 eV should not exist, according to the GZK bound. Conflicts between data and the bound have led to suggestions that laws of physics must be modified. We find that physical processes neglected in the early history terminate the LPM effect, important in calibrating the energy of electromagnetic and hadronic showers in the GZK energy regime. The processes neglected are the direct losses of electrons and positrons, overlooked by LPM and greatly augmented by ultra-high energy circumstances. We present an exact formula for direct energy losses of e+e- pairs in electromagnetic showers. Numerical integration in current hadronic models shows that actual energy losses are always substantially larger than LPM estimates, but the energy at which crossover occurs depends on models.