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Nucleon Polarisabilities from Compton Scattering on the Deuteron

Harald W. Griesshammer·Gautam Rupak
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Abstract

An analytic calculation of the differential cross section for elastic Compton scattering on the deuteron at photon energies ωin the range of 25-50 MeV is presented to next-to-next-to-leading order, i.e. to an accuracy of \sim 3%. The calculation is model-independent and performed in the low energy nuclear Effective Field Theory without dynamical pions. The iso-scalar, scalar electric and magnetic nucleon polarisabilities α_0 and β_0 enter as free parameters with a theoretical uncertainty of about 20%. Using data at $ω_{Lab}=49 MeV$ we find $α_0=8.4\pm 3.0(exp)\pm 1.7(theor)$, $β_0=8.9\pm 3.9(exp)\pm 1.8(theor)$, each in units of $10^{-4} fm^3$. With the experimental constraint for the iso-scalar Baldin sum rule, $α_0=7.2\pm 2.1(exp)\pm 1.6(theor)$, $β_0=6.9\mp 2.1(exp)\mp 1.6(theor)$. A more accurate result can be achieved by: (i) better experimental data, and (ii) a higher order theoretical calculation including contributions from a couple of so far undetermined four-nucleon-two-photon operators.

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Harald W. Griesshammer, Gautam Rupak. 2000-12-29. Nucleon Polarisabilities from Compton Scattering on the Deuteron. https://doi.org/10.1016/s0370-2693(02)01238-8

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