Precision extraction of the deuteron electric polarizability via the Baldin sum rule with full low-energy coverage

TL;DR

This study measures deuteron photodisintegration cross sections over a broad energy range and applies the Baldin sum rule to precisely determine the deuteron’s electric polarizability, resolving previous experimental-theoretical discrepancies.

Contribution

First application of the Baldin sum rule to dense experimental data to extract deuteron polarizabilities with high precision.

Findings

Sum of electric and magnetic polarizabilities: 0.719±0.009±0.014±0.023 fm³

Electric polarizability: 0.637±0.009±0.014±0.023±0.004 fm³

Results agree with theoretical predictions and resolve previous discrepancies.

Abstract

The photodisintegration cross sections of the deuteron have been systematically measured over the photon energy range of 2.33-19.65 MeV at the Shanghai Laser Electron Gamma Source (SLEGS). By applying the well-established Baldin sum rule to the newly obtained data, the sum of the electric and magnetic dipole polarizabilities of the deuteron is extracted for the first time based solely on a dense and continuous experimental dataset, yielding {\alpha}E +\{beta}M = 0.719\pm0.009stat\pm0.014algo\pm0.023syst fm3 . With theoretical values of the magnetic polarizability \{beta}M calculated from the pionless effective field theory, a new value of the electric polarizability is obtained as {\alpha}E = 0.637 \pm 0.009stat \pm 0.014algo \pm 0.023syst \pm 0.004theo fm3 , which is in excellent agreement with current theoretical predictions. This result resolves the previous discrepancy between experimental measurements from elastic scattering and theory, providing a high-precision benchmark for nuclear interaction models.