Experiments with 3 MW D0 injection have been carried out in the Gas Dynamic Trap (GDT) to simulate the axial profile of the fusion reaction intensity in the projecting neutron source based on the GDT1. Quite narrow angular distribution function of the fast ions produced by an oblique neutral beam injection results in a peaked axial profile of the fusion yield. This strong peaking is essential to produce intense neutron flux in the testing zones of the GDT–based neutron source.

The scintillation counters were installed in the central cell of the device to monitor the DD fusion reactions products: neutrons (2.45 MeV) and protons (3.02 MeV). Scintillation detectors were located closely to the plasma column inside of the vacuum vessel to avoid contribution from the scattered neutrons and to improve spatial resolution of the measurements. Longitudinal profiles of 2.45 MeV neutrons and 3.02 MeV protons have been measured in the high-beta regime of the GDT operation.

In the paper the experimental data are compared with the results of numerical simulations 2. The conclusion is drawn that the kinetics of the fast ion relaxation and scattering is determined by classical Coulomb collisions 3.