Development of a 20 mA negative hydrogen ion source for cyclotrons

Abstract

Effect due to plasma electrode adsorbates upon the negative ion current and electron current extracted from a negative ion source AIP Conference Proceedings 1869, 030025 (2017) Abstract. A cesiated DC negative ion source has been developed for proton cyclotrons in medical applications. A continuous H − beam of 23 mA was stably extracted at an arc power of 3 kW. The beam current gradually decreases with a constant arc power and without additional Cs injection and the decay rate was about 0.03 mA (0.14%) per hour. A feedback control system that automatically adjusts the arc power to stabilize the beam current is able to keep the beam current constant at ±0.04 mA (±0.2%).

Negative-hydrogen-ion production from a nanoporous 12CaO ∙ 7Al2O3 electride surface

“…3) Smallsize negative ion sources are now under development for applications in accelerators in medical fields. 4) Negative ion sources have recently received a significant attention owing to their application in microelectronics fields, such as proton implantation for surface modification, or smart-ion-beam cut of wafers, 5,6) as the charge-up problem of positive ion injection can be avoided.…”

An overview of negative hydrogen ion sources for accelerators

“…Japan A caesiated filament-driven multicusp H − source is being developed for medical cyclotrons at Sumitomo Heavy Industries. The source can produce 23 mA CW beams [34].…”

Numerical study of the plasma meniscus shape and beam optics in RF negative ion sources

“…The negative hydrogen ion(H − ) sources have various applications, for example, high energy particle physics [1,2], fusion plasma heating [3][4][5][6] and medical applications [7,8]. H − ion sources are required to produce high intensity beams with good convergence for these applications.…”