--- Robin van Spaandonk wrote: > So why can't a high energy gamma-ray be absorbed by a nucleus of oxygen/nitrogen in the upper atmosphere, and strip a proton off (or tear the nucleus to shreds), which then have extreme energy?
....this happeans all the time, except for the "extreme" part. It is called spallation.... there are definite QM limits as to how much energy can be transfered to any one particle and it is way too small. Usually after a neutron (of a few MeV) is "boiled off" in spallation - then another but slightly lower high energy gamma-ray is reemitted and this can go on for many steps. This can be worked out in Feynman diagrams and QED but it is nowhere close to what is seen with the Cygnet.
