Neutron-neutron quasifree scattering in neutron-deuteron breakup at 10 MeV

New measurements of the neutron-neutron quasifree scattering cross section in neutron-deuteron breakup at an incident neutron energy of 10.0 MeV are reported. The experiment setup was optimized to evaluate the technique for determining the integrated beam-target luminosity in neutron-neutron coincidence cross-section measurements in neutron-deuteron breakup. The measurements were carried out with a systematic uncertainty of \(\pm 5.6 \%\). Our data are in agreement with theoretical calculations performed using the CD-Bonn nucleon-nucleon potential in the Faddeev formalism. The measured integrated cross section over the quasifree peak is \(20.5 \pm 0.5 \text{(stat)} \pm 1.1 \text{(sys)}\) mb/sr\(^2\) in comparison with the theory prediction of 20.1 mb/sr\(^{2}\). These results validate our technique for determining the beam-target luminosity in neutron-deuteron breakup measurements.