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First Measurements of the Double-Polarization Observables $F$, $P$, and $H$ in $omega$ Photoproduction off Transversely Polarized Protons in the $N^ast$ Resonance Region

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 نشر من قبل Volker Crede
 تاريخ النشر 2018
  مجال البحث
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First measurements of double-polarization observables in $omega$ photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry $F$ has been measured using circularly polarized, tagged photons in the energy range 1200 - 2700 MeV, and the beam-target asymmetries $H$ and $P$ have been measured using linearly polarized tagged photons in the energy range 1200 - 2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon ($N^ast$) resonances. In particular, contributions from new $N^ast$ resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.



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