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Deuteron Compton Scattering in Effective Field Theory: Spin-Dependent Cross Sections and Asymmetries

Jiunn-Wei Chen·Xiangdong Ji·Yingchuan Li
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Abstract

Polarized Compton scattering on the deuteron is studied in nuclear effective field theory. A set of tensor structures is introduced to define 12 independent Compton amplitudes. The scalar and vector amplitudes are calculated up to ${\cal O}((Q/Λ)^2)$ in low-energy power counting. Significant contribution to the vector amplitudes is found to come from the spin-orbit type of relativistic corrections. A double-helicity dependent cross section $Δ_1 σ= (σ_{+1-1}-σ_{+1+1})/2$ is calculated to the same order, and the effect of the nucleon isoscalar spin-dependent polarizabilities is found to be smaller than the effect of isoscalar spin-independent ones. Contributions of spin-independent polarizabilities are investigated in various asymmetries, one of which has as large as 12 (26) percent effect at the center-of-mass photon energy 30 (50) MeV.

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Jiunn-Wei Chen, Xiangdong Ji, Yingchuan Li. 2004-11-08. Deuteron Compton Scattering in Effective Field Theory: Spin-Dependent Cross Sections and Asymmetries. https://doi.org/10.1103/physrevc.71.044321

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