Exploring the limits of a hadronic picture of nuclei through pion and nucleon removal reactions

A relativistic and quantum mechanical framework to compute nuclear transparencies for pion and nucleon production reactions is presented. Final state interactions for the ejected pions and nucleons are implemented in a relativistic Glauber eikonal approach. The proposed model can account for the color transparency (CT) phenomenon and short-range correlations (SRC) in the nucleus. Results are presented for kinematics corresponding to completed experiments for A(gamma,pi -p), A(e, e’ pi+) and A(gamma, pp). The influence of CT and SRC on the nuclear transparency is studied. Both the SRC and CT mechanisms increase the nuclear transparency. The two mechanisms can be clearly separated, though, as they exhibit a completely different dependence on the hard-scale parameter. Recent A(e, e pi+) results point towards the early onset of the CT phenomenon in pion production processes. The similarities in the trends and magnitudes of the computed nuclear transparencies compared to semi-classical models indicate that they are not subject to strong model dependencies. A comparison made in the model between the density dependence of the A(e, e’p), A(p, 2p) and A(gamma, pp) reactions shows that the bulk of the (gamma, pp) strength stems from the high density regions in the deep nuclear interior. Despite the strong attenuation, sizable densities can be probed by (p, 2p) provided that the energy resolution allows one to pick nucleons from s orbits. The effective mean densities that can be probed in high-energy (e, e’p) are of the order of 30-50% of the nuclear saturation density.

Grantor dc:publisher

Ghent University. Faculty of Sciences

Year dc:date

2009

Author dc:creator

• Cosyn, Wim

Contributors dc:contributor

• Ryckebusch, Jan

• Physics and Astronomy

Statement dc:rights

• info:eu-repo/semantics/openAccess

Language dc:language

eng

Identifier

https://biblio.ugent.be/publication/733500
https://biblio.ugent.be/publication/733500/file/4334981

OAI identifier oai:identifier

oai:archive.ugent.be:733500