The paper reports on the results of neutral beam heated high-β two-component plasma confinement studies in Gas-Dynamic Trap experiment1,2. The diagnostic set enabled us to characterize the different energy losses channels in the GDT3. The energy balance models were applied for analysis of plasma heating4. The experimental results on the measurements of the local energy and angular distributions of the fast ions minority are described. These measurements were done by injection of focused diagnostic neutral beam served to produce local charge-exchange target for fast ions5. Charge-exchange atoms were registered by an electrostatic energy analyzer. The energy distribution function obtained with this diagnostic was compared in detail with the results of Monte-Carlo6 and Fokker-Planck simulations7.