Eur. Phys. J. A (2006) 29: 189-207
https://doi.org/10.1140/epja/i2006-10075-y

Hadron Physics

Low-energy pions in nuclear matter and ππ photoproduction within a BUU transport model

Institut für Theoretische Physik, Universität Giessen, Germany

^* e-mail: oliver.buss@theo.physik.uni-giessen.de;

Received: 2 March 2006
Accepted: 26 July 2006
Published online: 28 August 2006

Abstract

A description of the low-energy scattering of pions and nuclei within a BUU transport model is presented. Implementing different scenarios of medium modifications, the mean free path of pions in nuclear matter at low momenta and pion absorption reactions on nuclei have been studied and compared to data and to results obtained via quantum-mechanical scattering theory. We show that even in a regime of a long pionic wavelength the semi-classical transport model is still a reliable framework for pion kinetic energies greater than ≈ 20-30MeV. Results are presented on π-absorption cross-sections in the regime of 10 MeV ⩽ T ^π _kin ⩽ 130MeV and on photon-induced ππ production at incident beam energies of 400-500MeV.