0000000000372650
AUTHOR
O Tarvainen
Measurement of ionization, charge exchange and ion confinement times in charge breeder ECR ion sources with short pulse 1+ injection of metal ions
Abstract The Consecutive Transients (CT) method is used for estimating the characteristic times of ionization, charge exchange and confinement within the plasma of a Charge Breeder Electron Cyclotron Resonance Ion Source (CB-ECRIS). The method reveals differences in the characteristic times between different source configurations, with K9+ charge breeding efficiencies of 8.9 % and 20.4 %, and allows qualitative explanation of the improved breeding efficiency. The increase in K9+ efficiency is accompanied by a decrease in ionization time for low charge states, a decrease of charge exchange time for high charge states, and an overall decrease of the ion confinement time, which increases non-l…
Recent developments and results of the LPSC PHOENIX type ECR charge breeder
Abstract Four models of the PHOENIX ECR charge breeder have been manufactured for ISOL application. Two are currently under operation at TRIUMF (ISAC) and GANIL (SPIRAL 1) while the SPES one is being installed on the facility. The last model is set on the LPSC 1+N+ test bench where a R&D program is ongoing to improve its performances. The last modifications consisted in improving the beam line vacuum and the alignment. Commissioning experiments showed an improvement of the charge breeder performances for all the tested species. The global CB efficiency is close to 100% for Cs when correcting the measurements with the beam transmission. Na and K efficiencies have increased significantly …
Empirical study of multidimensional Child-Langmuir law with plasma ion source extraction using round apertures
Abstract One dimensional Child-Langmuir (CL) law is commonly used in ion source physics to describe space charge limited ion extraction from the plasma. Recently 2D and 3D CL laws have been derived, but plasma ion extraction does not strictly meet the assumptions in these CL laws. Investigations on the applicability of the CL laws to ion source extraction were conducted using filament-driven ion source, measuring the beam currents as a function of extraction voltage. The experiments are complemented with simulations where IBSimu is used for studying the behaviour of plasma meniscus. Three different voltage regions were identified with low, moderate and high voltage. With moderate voltages t…