Münster 2002 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 40: Electromagnetic and Hadronic Probes V
HK 40.1: Gruppenbericht
Donnerstag, 14. März 2002, 14:00–14:30, D
Electroproduction of Strangeness on Light Nuclei* — •Frank Dohrmann — FZ Rossendorf, Inst. f. Kern- u. Hadronenphysik, Dresden, Germany
Jefferson Lab experiment E91016 recently studied the electroproduction of kaons, A(e,e ′ K+), on targets of H2, D2, 3He, 4He, C and Al. The variety of nuclear targets involved allows for a study of the dependences of the elementary processes involving strange hadrons upon both mass number and nuclear density. In particular, the measurements on 3,4He are the first performed. Results for the missing mass spectra from the various targets will be shown. Quantitative descriptions of these spectra need to take into account hyperon-nucleon (YN) final state interactions that are sensitive to YN potentials. The quasifree production cross sections and their angular and energy dependence for the Λ and Σ hyperons on the various target nuclei will be presented. It is of special interest to determine if the elementary production mechanisms are subject to medium modifications. Specifically, since the Λ and Σ hyperons have different isospins, medium modifications may have potentially different effects on the production of these hyperons. The presence of Λ and possible Σ hypernuclear states will be addressed. We see clear evidence for the Λ4H on 4 He as well as the Λ12B bound state on carbon. (* this work was supported in part by the A.v.Humboldt-Stiftung through a Feodor Lynen-Fellowship)