Determination of the scalar polarizabilities of the proton using beam asymmetry ${\Sigma }_3$ in Compton scattering

Abstract

The scalar dipole polarizabilities, ${\alpha }_{E1}$ and ${\beta }_{M1}$, are fundamental properties related to the internal dynamics of the nucleon. The currently accepted values of the proton polarizabilities were determined by fitting to unpolarized proton Compton scattering cross section data. The measurement of the beam asymmetry ${\Sigma }_3$ in a certain kinematical range provides an alternative approach to the extraction of the scalar polarizabilities. At the Mainz Microtron (MAMI) the beam asymmetry was measured for Compton scattering below pion photoproduction threshold for the first time. The results are compared with model calculations and the influence of the experimental data on the extraction of the scalar polarizabilities is determined.

arXiv comment6 pages, 5 figures

References in corpus (15)

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Cited by in corpus (9)

• Dispersion Theory in Electromagnetic Interactions
• Magnetic polarisability of the nucleon using a Laplacian mode projection
• Designing Optimal Experiments: An Application to Proton Compton Scattering
• Proton scalar dipole polarizabilities from real Compton scattering data, using fixed-t subtracted dispersion relations and the bootstrap method
• Partial-wave analysis of proton Compton scattering data below the pion-production threshold
• Comprehensive Study of Observables in Compton Scattering on the Nucleon
• Proton Compton Scattering from Linearly Polarized Gamma Rays
• Electromagnetic proton-neutron mass difference
• First concurrent extraction of the leading-order scalar and spin proton polarizabilities