New Neutron Polarizabilities from Deuterium Compton Scattering at HI$γ$S

D. Godagama; M. W. Ahmed; B. Crowe; G. Feldman; F. Friesen; H. Gao; H. W. Grießhammer; D. Hornidge; C. R. Howell; H. J. Karwowski; M. A. Kovash; K. K. H. Leung; M. Lewis; C. Malone; E. Mancil; D. Markoff; J. A. McGovern; S. Mikhailov; D. R. Phillips; M. H. Sikora; Y. K. Wu; J. Zhou

arXiv · 2611.06609

New Neutron Polarizabilities from Deuterium Compton Scattering at HI$γ$S

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Abstract

Elastic and inelastic Compton-scattering cross sections of the deuteron were measured at HI$γ$S using a circularly polarized, quasi-monoenergetic $γ$-ray beam (61.0 MeV). Scattered $γ$ rays from a liquid deuterium target were detected at $55^\circ$, $115^\circ$, and $150^\circ$. High-resolution NaI(Tl) detectors at backward angles enabled separation of elastic and inelastic events. A $χ$EFT analysis of the data yields new neutron scalar polarizabilities, $α^n_{E1} = 12.25 \pm 1.1\mathrm{(stat)} \pm 0.3\mathrm{(BSR)} \pm 0.8\mathrm{(th)}$ and $β^n_{M1} = 2.95 \mp 1.1\mathrm{(stat)} \mp 0.3\mathrm{(BSR)} \mp 0.8\mathrm{(th)}$ (in units of $10^{-4} \mathrm{fm}^3$) reducing statistical uncertainties by 12 %.

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D. Godagama, M. W. Ahmed, B. Crowe, G. Feldman, F. Friesen, H. Gao, H. W. Grießhammer, D. Hornidge, C. R. Howell, H. J. Karwowski, M. A. Kovash, K. K. H. Leung, M. Lewis, C. Malone, E. Mancil, D. Markoff, J. A. McGovern, S. Mikhailov, D. R. Phillips, M. H. Sikora, Y. K. Wu, J. Zhou. 2026-11-04. New Neutron Polarizabilities from Deuterium Compton Scattering at HI$γ$S. https://arxiv.org/abs/2611.06609

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