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تسجيل مستخدم جديدLight Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory
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تأليف
Volker Crede
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Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom underlying nucleon matter. High-energy electrons and photons are a remarkably clean probe of hadronic matter, providing a microscope for examining the nucleon and the strong nuclear force. Current experimental efforts with the CLAS spectrometer at Jefferson Laboratory utilize highly-polarized frozen-spin targets in combination with polarized photon beams. The status of the recent double-polarization experiments and some preliminary results are discussed in this contribution.
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Photoproduction cross sections are reported for the reaction $gamma pto peta$ using energy-tagged photons and the CLAS spectrometer at Jefferson Laboratory. The $eta$ mesons are detected in their dominant charged decay mode, $etato pi^+pi^-pi^0$, and
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The spectrum of nucleon excitations is dominated by broad and overlapping resonances. Polarization observables in photoproduction reactions are key in the study of these excitations. They give indispensable constraints to partial-wave analyses and he
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