Investigating Neutron Polarizabilities through Compton Scattering on ${}^3$He

Abstract

We examine manifestations of neutron electromagnetic polarizabilities in coherent Compton scattering from the Helium-3 nucleus. We calculate ${\gamma }^3$He elastic scattering observables using chiral perturbation theory to next-to-leading order ($\mathcal{O}(e^{2}Q)$). We find that the unpolarized differential cross section can be used to measure neutron electric and magnetic polarizabilities, while two double-polarization observables are sensitive to different linear combinations of the four neutron spin polarizabilities. [Note added in 2018] An erratum for this paper has been posted as arXiv:1804.01206. Overall conclusions are unchanged, but quantitative results are affected appreciably.

Comments: 4 pages, 4 figures; version published in Phys. Rev. Lett