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We investigate meson electroproduction off complex nuclei in the kinematic regime of the HERMES experiment using a semi-classical transport model which is based on the Boltzmann­Uehling­Uhlenbeck (BUU) equation. We discuss coherence length and color transparency effects in exclusive ρ0 production as well as hadron formation and attenuation of charged pions, kaons, protons and anti-protons in deep inelastic lepton scattering off nuclei. [ABSTRACT FROM AUTHOR]

The lifetime of heavy hypernuclei has been determined at COSY Ju¨lich making use of the (p,K)-reaction and the recoil-shadow technique based on the detection of fragments from the Λ-decay induced fission. Hypernuclei were produced by bombarding extremely thin U and Bi targets with protons of 1.5 GeV and 1.9 GeV kinetic energy. High luminosity was achieved due to the multi-pass technique with the target being exposed to the internal beam of COSY. Position sensitive low pressure MWPCs permitted clear identification of fission fragments based on energy loss and TOF information. The lifetime of hypernuclei was deduced from the position distributions of fission events in the shadow region and from the recoil momentum calculated within the BUU model. Values of 240±60 ps and 161±7(stat.)±14(syst.)ps were found with U and Bi-targets, respectively. The deduced production cross sections for hot hypernuclei prior to the evaporation process of σ=150[sub -80][sup +150] μb for U and 350±140 μb for Bi are in agreement with the theoretical predictions. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present a transport theoretical analysis of hadron attenuation in deep inelastic lepton scattering (DIS) off complex nuclei in the kinematic regime of the HERMES experiment. The HERMES data indicate the presence of strong prehadronic final state interactions shortly after the elementary lepton-nucleon interaction. The contribution of such (pre-)hadronic final state interactions to the observed jet quenching in ultra-relaticistic heavy ion collisions (HIC) at RHIC is estimated under the assumption that a similar space-time picture for hadronization also holds in a hot hadronic medium. Our results show that an additional mechanism for jet quenching must be at work for most central collisions. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]