High-current ${\mathrm{H}}_3^{+}$ DC beam production with a miniaturized microwave driven ion source at Peking University

In recent years, the widespread use of ${\mathrm{H}}_3^{+}$ ion beams across various fields, such as high-intensity proton cyclotrons, nuclear physics, astronomy, etc., has created an urgent demand for high-current ${\mathrm{H}}_3^{+}$ ion sources. However, ion sources capable of generating direct-current (DC) ${\mathrm{H}}_3^{+}$ ion beams of several milliamperes remain scarce to date. Recently, a miniaturized microwave-driven ion source (MMDIS) with a DC 7.6 mA ${\mathrm{H}}_3^{+}$ ion beam has been developed at Peking University (PKU), operating at an RF power of only 80 W. Beam analysis indicates that the ${\mathrm{H}}_3^{+}$ fraction in the MMDIS extracted beam can reach 68.5%. These results provide a valuable reference for the utilization of ${\mathrm{H}}_3^{+}$ beams.