2002/02/28 by Diego Harari, Silvia Mollerach, Esteban Roulet +2 · 4 citations
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Coherence (philosophical gambling strategy) #Coherence length #Cosmic ray #Dark Matter and Cosmic Phenomena #Magnetic field #Magnification #Range (aeronautics) #Scintillation #Solar and Space Plasma Dynamics #astro-ph #hep-ph
paper · pdf · doi:10.1088/1126-6708/2002/03/045
published as JHEP 0203 (2002) 045 · 30 pages, 16 figures, final version with minor changes
openalex publication_date 2002/03/20 · arxiv created 2002/03/26 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We consider the propagation of ultra high energy cosmic rays through turbulent magnetic fields and study the transition between the regimes of single and multiple images of point-like sources. The transition occurs at energies around Ec≃ Z~41 \rm EeV(Brms/5 μ\rm G) (L/ 2 \rm kpc)3/2√50 \rm pc/Lc, where L is the distance traversed by the CR's with electric charge Ze in the turbulent magnetic field of root mean square strength Brms and coherence length Lc. We find that above 2 Ec only sources located in a fraction of a few % of the sky can reach large amplifications of its principal image or start developing multiple images. New images appear in pairs with huge magnifications, and they remain amplified over a significant range of energies. At decreasing energies the fraction of the sky in which sources can develop multiple images increases, reaching about 50% for E>Ec/2. The magnification peaks become however increasingly narrower and for E<Ec/3 their integrated effect becomes less noticeable. If a uniform magnetic field component is also present it would further narrow down the peaks, shrinking the energy range in which they can be relevant. Below E≃ Ec/10 some kind of scintillation regime is reached, where many demagnified images of a source are present but with overall total magnification of order unity. We also search for lensing signatures in the AGASA data studying two-dimensional correlations in angle and energy and find some interesting hints.