High-current H₃⁺ DC beam production with a miniaturized microwave driven ion source at Peking University

In recent years, the widespread use of H_3^+ ion beams across various fields, such as high-intensity proton cyclotrons, nuclear physics, astronomy, etc., has created an urgent demand for high-current H_3^+ ion sources. However, ion sources capable of generating direct-current (DC) H_3^+ ion beams of several milliamperes remain scarce to date. Recently, a miniaturized microwave- driven ion source (MMDIS) with a DC 7.6 mA H_3^+ ion beam has been developed at Peking University (PKU), operating at an RF power of only 80 W. Beam analysis indicates that the H_3^+ fraction in the MMDIS extracted beam can reach 68.5%. These results provide a valuable reference for the utilization of H_3^+ beams.