The photodisintegration of cosmic ray nuclei by solar photons: the Gerasimova-Zatsepin effect revisited

The interesting possibility of measuring the masses of high energy cosmic r ay particles by observing pairs of extensive air showers arriving at the ea rth nearly simultaneously was proposed some years ago by Zatsepin (1951) an d Gerasimova and Zatsepin (1960). Such showers would be created by the nucl ear fragments originating as a result of the photodisintegration of massive nuclei interacting with the solar radiation field. In this paper we revisi t this possibility in the context of existing and proposed detectors of hig h and ultra-high energy cosmic rays considering a simple, yet realistic, mo del of the interplanetary magnetic field. The possibility of observing the mass fragmentation of cosmic rays directly, however, remains challenging. ( C) 1999 Elsevier Science B.V.