Recoil polarization and beam-recoil double polarization measurement of eta electroproduction on the proton in the region of the S11(1535) resonance.
PHYSICAL REVIEW LETTERS 2007;
99:132301. [PMID:
17930579 DOI:
10.1103/physrevlett.99.132301]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Indexed: 05/25/2023]
Abstract
The beam-recoil double polarization P(x')(h) and P(z')(h) and the recoil polarization P(y') were measured for the first time for the p(e,e'p)eta reaction at a four-momentum transfer of Q(2) = 0.1 GeV(2)/c(2) and a center of mass production angle of theta = 120 degrees at the Mainz Microtron MAMI-C. With a center of mass energy range of 1500 MeV<W<1550 MeV the region of the S11(1535) and D13(1520) resonance was covered. The results are discussed in the framework of a phenomenological isobar model (Eta-MAID). While P(x')(h) and P(z')(h) are in good agreement with the model, P(y') shows a significant deviation, consistent with existing photoproduction data on the polarized-target asymmetry.
Collapse