English

Normalization discrepancies in photoproduction reactions

High Energy Physics - Phenomenology 2011-06-03 v1 Nuclear Experiment Nuclear Theory

Abstract

Recent CLAS photoproduction results using a tagged bremsstrahlung photon beam for the ground-state pseudoscalar meson photoproduction channels (K+ΛK^+ \Lambda, K+Σ0K^+ \Sigma^0, ηp\eta p, π+n\pi^+ n and π0p\pi^0 p) show a normalization discrepancy with older results from SLAC, DESY and CEA that used an untagged bremsstrahlung beam. The CLAS results are roughly a factor of two smaller than the older data. The CLAS K+ΛK^+\Lambda and K+Σ0K^+\Sigma^0 results are in excellent agreement with the latest LEPS results that also employed a tagged beam. For the vector meson (ωp\omega p and ϕp\phi p) channels, CLAS agrees with SLAC results that employed a linearly polarized beam using laser back-scattering, as well as Daresbury data that also came from tagged photon experiment. We perform a global survey of these normalization issues and stress on their significant effect on the coupling constants used in various partial wave analyses.

Keywords

Cite

@article{arxiv.1106.0479,
  title  = {Normalization discrepancies in photoproduction reactions},
  author = {Biplab Dey and Curtis A. Meyer},
  journal= {arXiv preprint arXiv:1106.0479},
  year   = {2011}
}

Comments

This expands upon a talk given at NSTAR'11. It is also a preliminary draft only

R2 v1 2026-06-21T18:16:50.704Z