A measurement of the differential cross section for the two-body photodisintegration of 3He at theta_LAB = 90deg using tagged photons in the energy range 14 -- 31 MeV

TL;DR

This study measured the differential cross section for the two-body photodisintegration of 3He at 90 degrees using tagged photons between 14 and 31 MeV, providing more accurate data that supports the inclusion of three-nucleon forces in theoretical models.

Contribution

It presents new, precise measurements of the 3He photodisintegration cross section at specific energies and angles, improving upon previous data and validating advanced Faddeev calculations.

Findings

Data agree with previous measurements

Supports inclusion of three-nucleon forces in models

Improved accuracy and precision over past data

Abstract

The two-body photodisintegration of 3He has been investigated using tagged photons with energies from 14 -- 31 MeV at MAX-lab in Lund, Sweden. The two-body breakup channel was unambiguously identified by the (nonsimultaneous) detection of both protons and deuterons. This approach was made feasible by the over-determined kinematic situation afforded by the tagged-photon technique. Proton- and deuteron-energy spectra were measured using four silicon surface-barrier detector telescopes located at a laboratory angle of 90deg with respect to the incident photon-beam direction. Average statistical and systematic uncertainties of 5.7% and 6.6% in the differential cross section were obtained for 11 photon-energy bins with an average width of 1.2 MeV. The results are compared to previous experimental data measured at comparable photon energies as well as to the results of two recent Faddeev calculations which employ realistic potential models and take into account three-nucleon forces and final-state interactions. Both the accuracy and precision of the present data are improved over the previous measurements. The data are in good agreement with most of the previous results, and favor the inclusion of three-nucleon forces in the calculations.