Coherent π{sup 0}-photoproduction on the deuteron near the η-production threshold including polarization observables

Journal Article · Mon Dec 15 04:00:00 EST 2014 · Annals of Physics (New York)

DOI:https://doi.org/10.1016/J.AOP.2014.08.008· OSTI ID:22403459

Al-Thoyaib, Suleiman S. ^[1]

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1. Physics Department, Faculty of Science, Qassim University, Buraydah 51452, P.O. Box 6644 (Saudi Arabia)

Coherent π{sup 0}-photoproduction on the deuteron including polarization observables is studied in the energy region near the η-production threshold at backward center-of-mass angles of the outgoing pion. This work is motivated by the measurements of the CLAS Collaboration at Jefferson Lab, where a cusp-like structure in the energy dependence of the differential cross section has been observed at extremely backward pion angles. The present approach is based on the impulse approximation and first-order rescattering diagrams with intermediate production of both π- and η-mesons. Numerical results for unpolarized cross sections, the linear photon asymmetry (Σ), the vector (T{sub 11}) and tensor (T{sub 2M}, M=0, 1, 2) deuteron target asymmetries, and the double polarization E-asymmetry are predicted and compared with available experimental data and other theoretical models. The effect of first-order rescattering is found to be much larger in spin asymmetries than in the unpolarized cross sections. It reaches on average about 40% in the tensor target and E asymmetries. Compared to the experimental data from CLAS Collaboration, sizable discrepancies are found. This is not the case for the linear photon asymmetry, for which a better comparison with the data from YerPhI Collaboration is obtained.

• OSTI ID: 22403459
• Journal Information: Annals of Physics (New York), Journal Name: Annals of Physics (New York) Vol. 351; ISSN 0003-4916; ISSN APNYA6
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ASYMMETRY
CEBAF ACCELERATOR
CENTER-OF-MASS SYSTEM
CUSPED GEOMETRIES
DEUTERIUM TARGET
DIFFERENTIAL CROSS SECTIONS
ENERGY DEPENDENCE
EXPERIMENTAL DATA
IMPULSE APPROXIMATION
PHOTONS
PHOTOPRODUCTION
PIONS
POLARIZATION
RESCATTERING
SPIN