Measuring Neutron-Carbon Scattering Angles with Diamond Detectors

The MoNA (Modular Neutron Array) Collaboration uses organic scintillator bars composed of carbon and hydrogen atoms to detect high-energy neutrons in experiments studying neutron-rich nuclei. While organic scintillators efficiently detect neutron collisions with hydrogen atoms in the scintillator, neutron-carbon collisions often escape detection. To better study fast neutron-carbon collisions, a neutron beam with energies up to 800 MeV was collimated onto two Cividec B8 Open-Design Diamond Detectors, which both acted as carbon scattering targets and recorded data on the time of flight and energy deposited in the diamonds. Particles exiting the diamond detectors were detected by hydrocarbon scintillator bars placed downstream of the diamonds, from which scattering angles were reconstructed. Protons, deuterons, and tritons were observed in the experimental data through distinct bands in plots of the energy deposited by the particle vs. particle velocity. Scattering angles for 50, 100, 150, and 200 MeV neutrons were constructed from events with a hit in a diamond and a scintillator bar. Scattering angles were also reconstructed for the protons, deuterons, and tritons found in the data. Future work will compare data to simulations with different neutron interaction packages.