jassemajaka@gmail.com
New Measurement of Σ Beam Asymmetry for η Meson Photoproduction on the Proton
New Measurement of Σ Beam Asymmetry for η Meson Photoproduction on the Proton
J. Ajaka et al.
Phys. Rev. Lett. 81, 1797 – Published 31 August 1998
We present new Σ beam asymmetry data for η meson photoproduction on the proton, using a novel tagged, laser backscattered, linearly polarized photon beam up to 1.1 GeV. The data show large, positive asymmetries, at all incident photon energies. In addition to the S11(1535) and D13(1520) resonances necessary to reproduce the cross sections, P13(1720) and D15(1675) “four stars” resonances contribute to the Σ observable, but cannot reproduce the strong forward asymmetries measured at energies higher than 900 MeV.
Received 2 February 1998
DOI: https://doi.org/10.1103/PhysRevLett.81.1797