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Photoproduction of phi mesons from the proton: Polarization observables and strangeness in the nucleon

Alexander I. Titov·Yongseok Oh·Shin Nan Yang·Tosiyuki Morii
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Abstract

The polarization observables in phi meson photoproduction is studied to probe the strangeness content of the nucleon. In addition to the dominant diffractive production and the one-pion-exchange process, we take into account the direct knockout mechanism that arises from the possible hidden strangeness content of the nucleon. We find that some double polarization observables are very sensitive to the strangeness content of the proton because of the different spin structures of the amplitudes associated with different mechanisms. This suggests that such measurements could be very useful in probing the strangeness content in the proton. The orbitally excited quark-cluster configurations in the proton are included in the calculation and found to have little effect.

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Alexander I. Titov, Yongseok Oh, Shin Nan Yang, Tosiyuki Morii. 1998-07-30. Photoproduction of phi mesons from the proton: Polarization observables and strangeness in the nucleon. https://doi.org/10.1103/physrevc.58.2429

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