First Experiments on the Investigation of the Generation of Negative Hydrogen Ions with the Use of CW ECR Discharge at the GISMO Facility

The results of the first experiments on studying the volume production of negative hydrogen ions using a dense gasdynamic plasma of an electron cyclotron resonance (ECR) discharge sustained by continuous wave (CW) microwave radiation from a gyrotron (28 GHz/5 kW) are described. The ECR hydrogen discharge is ignited in a vacuum chamber placed in a magnetic field created by a system of two consecutive magnetic traps. The system parameters are optimized to obtain the maximum average current density of negative ions at the level of j = 25 mA/cm². The study involves the determination of the negative ion production area, me-asurement of the current density dependences on gas pressure and microwave radiation power, and demonstration of potential optimization opportunities for extraction voltage.