The photodisintegration of cosmic ray nuclei by solar photons: the   Gerasimova-Zatsepin effect revisted
  The interesting possibility of measuring the masses of high energy cosmic ray particles by observing pairs of extensive air showers arriving at the earth nearly simultaneously was proposed some years ago by Gerasimova and Zatsepin (1960). Such showers would be created by the nuclear fragments originating as a result of the photodisintegration of massive nuclei interacting with the solar radiation field. In this paper we re-visit this possibility in the context of existing and proposed detectors of high and ultra-high energy cosmic rays considering a simple, yet realistic, model of the interplanetary magnetic field. The possibilty of observing the mass fragmentation of cosmic rays directly, however, remains challenging. 
Gustavo Medina Tanco (Inst.Astron.e Geof.-USP-Brasil & Univ.of   Leeds-UK) and Alan A. Watson (Dept.Phys.& Astron. Univ.of L...