Spin polarizabilities of the proton by measurement of Compton double-polarization observables

Abstract

The Compton double-polarization observable ${\Sigma }_{2z}$ has been measured for the first time in the $\Delta (1232)$ resonance region using a circularly polarized photon beam incident on a longitudinally polarized target at the Mainz Microtron. This paper reports these results, together with the model-dependent extraction of four proton spin polarizabilities from fits to additional asymmetry data using dispersion relation and chiral perturbation theory calculations, with the former resulting in: ${\gamma }_{E1E1}=-3.18\pm 0.52$, ${\gamma }_{M1M1}=2.98\pm 0.43$, ${\gamma }_{E1M2}=-0.44\pm 0.67$ and ${\gamma }_{M1E2}=1.58\pm 0.43$, in units of $10^{-4}{\mathrm{fm}}^4$.

arXiv comment7 pages, 5 figures, 2 tables, accepted for publication in PRC

References in corpus (20)

• Dispersion relations in real and virtual Compton scattering
• First measurement of the Gerasimov-Drell-Hearn integral for Hydrogen from 200 to 800 MeV
• Using effective field theory to analyse low-energy Compton scattering data from protons and light nuclei
• Upgrade of the Glasgow photon tagging spectrometer for Mainz MAMI-C
• Predictive powers of chiral perturbation theory in Compton scattering off protons
• Nucleon Polarizabilities: from Compton Scattering to Hydrogen Atom
• Higher Order Polarizabilities of the Proton
• Compton scattering on the nucleon at intermediate energies and polarizabilities in a microscopic model
• Determination of the Dalitz plot parameter alpha for the decay eta->3pi^0 with the Crystal Ball at MAMI-B
• Proton spin polarizabilities from polarized Compton scattering
• Measurements of Double-Polarized Compton Scattering Asymmetries and Extraction of the Proton Spin Polarizabilities
• Predictions of covariant chiral perturbation theory for nucleon polarisabilities and polarised Compton scattering
• Compton scattering from chiral dynamics with unitarity and causality
• Backward spin polarizability ${\gamma }_{\pi }$ of the proton
• Nucleon Polarisabilities at and Beyond Physical Pion Masses
• Incoherent pion photoproduction on ${}^{12}$C
• Evaluation of the forward Compton scattering off protons: I. Spin-independent amplitude
• Proton scalar dipole polarizabilities from real Compton scattering data, using fixed-t subtracted dispersion relations and the bootstrap method
• Evaluation of the forward Compton scattering off protons: II. Spin-dependent amplitude and observables
• Comprehensive Study of Observables in Compton Scattering on the Nucleon

Cited by in corpus (5)

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• Designing Optimal Experiments: An Application to Proton Compton Scattering
• Nucleon polarizabilities in covariant baryon chiral perturbation theory with explicit $\Delta$ degrees of freedom
• First concurrent extraction of the leading-order scalar and spin proton polarizabilities
• Energy of a point-like neutron in an external electromagnetic field