Beam commissioning and analysis of a continuous-wave window-type deuteron radio-frequency quadrupole

Abstract

As high-intensity beams are required for various applications, high-power, high-current, continuous-wave (CW) radio-frequency quadrupole (RFQ) accelerators have become a research focus in recent years and also a direction for development in the future. To master and accumulate the advanced technology in design, fabrication and operation of high-current CW RFQs, the RFQ group at Peking University has built a window-type CW RFQ, operating at 162.5[Formula: see text]MHz, to accelerate a 50-mA deuteron beam from 50[Formula: see text]keV to 1[Formula: see text]MeV. It is the first relatively high-frequency window-type CW RFQ in the world. A [Formula: see text] ion beam extracted from an electron cyclotron resonance (ECR) ion source was used for the beam commissioning because deuteron beam acceleration will produce a serious radiation risk. We compared and analyzed the measurement results obtained during the beam commissioning with simulations. The data show good consistency in many respects. For the discrepancies, we explain the issues in detail. We achieved stable and robust acceleration of about 1.5[Formula: see text]mA CW [Formula: see text] for 1[Formula: see text]h. Finally, we discuss the differences between [Formula: see text] ion beam acceleration and deuteron beam acceleration.