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Nucleon Polarisabilities from Deuteron Compton Scattering, and Its Lessons for Chiral Power Counting

Harald W. Griesshammer
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Abstract

A brief review of Compton scattering off the deuteron in Chiral Effective Field Theory, including gauge invariance and the correct Thomson limit. We model-independently determine the iso-scalar, spin-independent dipole polarisabilities of the nucleon at zero energy from all Compton data below 100 MeV as α_{E1}^s=11.3+-0.7_{stat}\+-0.6_{Baldin}+-1_{theory}, β_{M1}^s=3.2-+0.7_{stat}+-0.6_{Baldin}+-1_{theory}, each in 10^{-4} fm^3. Proton and neutron polarisabilities are therefore identical within (predominantly statistical) errors.

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Harald W. Griesshammer. 2006-11-20. Nucleon Polarisabilities from Deuteron Compton Scattering, and Its Lessons for Chiral Power Counting. https://doi.org/10.1142/9789812790804_0074

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