Energy spectrum of longitudinal ion losses in the GDT facility under development of Alfv,n ion-cyclotron instability

The influence of Alfv,n ion cyclotron instability on the longitudinal losses of particles and energy from the GDT gas-dynamic trap was studied experimentally. To record the energy spectrum of ions escaping from the facility along magnetic field lines, a wide-range energy analyzer was attached to the expander. Processing of the experimental data made it possible to determine the time evolution of the ion energy distribution function and showed that the relative increase in the loss power during the development of instability did not exceed 1%. This result confirms the main conclusion of the theoretical model describing the interaction between an Alfv,n wave and resonance particles and predicting that this microinstability insignificantly affects the confinement of hot ions in open magnetic traps.