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

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