Parton fluxes and virtual pions in heavy nuclei

Abstract

The partonic flux originated from a heavy nucleus is not the mere sum of the fluxes coming from the individual nucleons. There are various effects that give rise to modifications. One of these effects is here investigated i.e. the presence of a cloud of virtual pions co-moving with the nucleus. It is found that the contribution of these virtual particles to the total parton flux should be rather small even if one includes the contribution of resonances.