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The absolute differential cross sections for the 3He(γ,n)pp reaction were measured as a function of outgoing neutron scattering angle and energy at the incident γ-ray energies of 12.8, 13.5, and 14.7 MeV to within a precision better than ±6%. Both the absolute cross sections and the neutron energy distributions at each incident γ-ray energy agree with the state-of-the-art theoretical results when the Coulomb interaction in the final state is included. [ABSTRACT FROM AUTHOR]

Differential cross sections for elastic scattering of photons from the deuteron have recently been measured at the Tagged-Photon Facility at the MAX IV Laboratory in Lund, Sweden. These first new measurements in more than a decade further constrain the isoscalar electromagnetic polarizabilities of the nucleon and provide the first-ever results above 100 MeV, where the sensitivity to the polarizabilities is increased. We add 23 points between 70 and 112 MeV, at angles 60°, 120°, and 150°. Analysis of these data using a chiral effective field theory indicates that the cross sections are both self-consistent and consistent with previous measurements. Extracted values of αs=[12.1±0.8(stat)±0.2(BSR)±0.8(th)]××10-4fm3 and βs=[2.4±0.8(stat)±0.2(BSR)±0.8(th)]×10-4fm3 are obtained from a fit to these 23 new data points. This paper presents in detail the experimental conditions and the data analysis used to extract the cross sections. [ABSTRACT FROM AUTHOR]

Compton scattering cross sections from 6Li have been measured at scattering angles of 40°-160° using a nearly monoenergetic 60-MeV photon beam at the High Intensity Gamma-Ray Source. A phenomenological model provides an estimate of the sensitivity of the 6Li(y, y)6Li cross section to the nucléon isoscalar electromagnetic polarizabilities αs and βs. [ABSTRACT FROM AUTHOR]

A photofission experiment was performed on targets of 235U, 238U, 239Pu, and 232Th using nearly 100% linearly polarized, high-intensity (∼107 &ggr;/s), and nearly monoenergetic &ggr;-ray beams having energies between 5.6 and 7.3 MeV at the High Intensity &ggr;-ray Source (Hl&ggr;S). An array of 18 liquid scintillator detectors was used to measure prompt fission neutron polarization asymmetries. An asymmetry close to zero was found for 235U and 239Pu while a significant asymmetry (∼0.5) was found for 238U and 232Th. A simplified model of near-threshold photofission has been developed in an attempt to explain the systematic difference between the even-even and even-odd targets. The results of a simulation, based on this model and using previous measurements of fission fragment angular distributions, are shown to accurately reproduce the essential features of the data. [ABSTRACT FROM AUTHOR]