Neutron polarizabilities investigated by quasi-free Compton scattering from the deuteron

Abstract

Measuring Compton scattered photons and recoil neutrons in coincidence, quasi-free Compton scattering by the neutron has been investigated at MAMI (Mainz) at $thet{a}_{\hat{I}}^3=136^o$ in an energy range from 200 to 400 MeV. From the data a polarizability difference of $\hat{I}{\pm }_n-{\hat{I}}_n^2=9.8\pm 3.6(stat{)}_{-1.1}^{+2.1}(syst)\pm 2.2(model)$ in units of $10^{-4}f{m}^3$ has been determined. In combination with the polarizability sum $\hat{I}{\pm }_n+{\hat{I}}_n^2=15.2\pm 0.5$ deduced from photo absorption data, the neutron electric and magnetic polarizabilities, $\hat{I}{\pm }_n=12.5\pm 1.8(stat{)}_{-0.6}^{+1.1}(syst)\pm 1.1(model)$ and ${\hat{I}}_n^2=2.7\mp 1.8(stat{)}_{-1.1}^{+0.6}(syst)\mp 1.1(model)$, are obtained.