Measurement of the left-right asymmetry inπ−p→γnfrom 301 to 625 MeV/cat backward angles
- 1 February 1991
- journal article
- research article
- Published by American Physical Society (APS) in Physical Review D
- Vol. 43 (3), 687-695
- https://doi.org/10.1103/physrevd.43.687
Abstract
The left-right asymmetry of has been measured using a transversely polarized target at seven pion momenta from 301 to 625 MeV/c, mostly at photon angles of 90° and 110° c.m. The final-state and neutron were detected in coincidence. Neutrons were recorded in two arrays of plastic scintillators and the in two matching sets of lead-glass counters. The results are compared with the predictions from the two most recent single-pion photoproduction partial-wave analyses. The agreement with the analysis of Arai and Fujii is poor, casting some doubt on the correctness of their values for the radiative decay amplitude of the neutral Roper resonance which are used widely. The agreement is much better with the results of the VPI analysis. Also, a comparison is made with the recoil-proton polarization data from the inverse reaction measured at 90° with a deuterium target. It reveals substantial discrepancies, indicating the shortcomings of the deuterium experiments for neutron target experiments. Our data are also compared with several bag-model calculations.
Keywords
This publication has 37 references indexed in Scilit:
- Photoproduction of delta and Roper resonances in the cloudy bag modelPhysical Review D, 1988
- Left-Right Asymmetry in Inverseπ−Photoproduction from a Transversely Polarized Proton TargetPhysical Review Letters, 1986
- A phenomenological Hamiltonian for the pion photoproduction reaction and π-nucleus dynamicsJournal of Physics G: Nuclear Physics, 1985
- Pion photoproduction in theregion and chiral bag modelsPhysical Review D, 1983
- Where are hermaphrodite baryons?Physics Letters B, 1983
- waves in the nucleon: A test of color magnetismPhysical Review D, 1982
- Phenomenological Analysis of Single-Pion PhotoproductionPhysical Review B, 1969
- Electromagnetic Decays of Baryon Resonances in the Harmonic-Oscillator ModelPhysical Review B, 1969
- Photoproduction ofResonances in the Quark ModelPhysical Review Letters, 1966
- Possible,Noninvariance in the Electromagnetic InteractionPhysical Review B, 1965