ECRIS2012 - List of Keywords (space-charge)

Paper	Title	Other Keywords	Page
TUZO03	New Extraction Design for the JYFL 14 GHz ECRIS	extraction, simulation, ion, plasma	34
	V. Toivanen, T. Kalvas, H. A. Koivisto, J.P.O. Komppula, O.A. Tarvainen JYFL, Jyväskylä, Finland
	Funding: VT acknowledges the financial support of the Ehrnrooth foundation. A new extraction system has been designed and constructed for the JYFL 14 GHz ECRIS at the Department of Physics, University of Jyväskylä (JYFL). The goal of the new design is to improve the performance of the ion source and increase the transmission efficiency of the low energy beam transport and the accelerator. The new extraction system is designed to be able to handle higher beam currents, yield better beam quality and offer more tuning flexibility. The design was made with the aid of simulations performed with the IBSimu code. The suitability of the code for this task was verified by simulating the old extraction system and good agreement between simulations and measurements was achieved. The new extraction system has been constructed, installed and tested. The new design, simulations and the first measurement results will be presented.
	Slides TUZO03 [4.470 MB]

TUZO04	Space Charge Compensation Measurements of Multicharged Ion Beams Extracted from an ECR Ion Source	ion, electron, ECR, simulation	38
	D. Winklehner LBNL, Berkeley, California, USA D.G. Cole, D. Leitner, G. Machicoane, F. Marti, L. Tobos NSCL, East Lansing, Michigan, USA
	Space charge compensation* due to the interaction of the beam with residual gas molecules is a well-known phenomenon for high current injector beam lines. For beam lines using mostly magnetic focusing elements and for pressure above 10^-6 mbar, full neutralization has been observed. However, due to the low pressure required for the efficient transport of high charge state ions, beams in ECR injector lines are typically only partly neutralized. With the performance increase of the next generation ECR ion sources it is possible to extract tens of mA of beam current. In this high current regime, non-linear focusing effects due to the space-charge potential of the beam become more and more important. In order to develop a realistic simulation model for low energy beam transport lines, it is important to estimate the degree of space charge compensation. In this contribution we report on measurements of the beam potential (and neutralization), performed after the extraction region of the ECR ion source, in dependence of the base pressure in the beam line and other source parameters using a Retarding Field Analyzer (RFA). Results are discussed and compared to simulations. * When the beam interacts with the residual gas, electrons are separated from gas molecules and accumulate inside the beam envelope, thereby compensating the space-charge (aka neutralization)
	Slides TUZO04 [4.192 MB]

Paper

Title

Other Keywords

Page

TUZO03

New Extraction Design for the JYFL 14 GHz ECRIS

extraction, simulation, ion, plasma

34

V. Toivanen, T. Kalvas, H. A. Koivisto, J.P.O. Komppula, O.A. Tarvainen
JYFL, Jyväskylä, Finland

Funding: VT acknowledges the financial support of the Ehrnrooth foundation.
A new extraction system has been designed and constructed for the JYFL 14 GHz ECRIS at the Department of Physics, University of Jyväskylä (JYFL). The goal of the new design is to improve the performance of the ion source and increase the transmission efficiency of the low energy beam transport and the accelerator. The new extraction system is designed to be able to handle higher beam currents, yield better beam quality and offer more tuning flexibility. The design was made with the aid of simulations performed with the IBSimu code. The suitability of the code for this task was verified by simulating the old extraction system and good agreement between simulations and measurements was achieved. The new extraction system has been constructed, installed and tested. The new design, simulations and the first measurement results will be presented.

Slides TUZO03 [4.470 MB]

TUZO04

Space Charge Compensation Measurements of Multicharged Ion Beams Extracted from an ECR Ion Source

ion, electron, ECR, simulation

38

D. Winklehner
LBNL, Berkeley, California, USA
D.G. Cole, D. Leitner, G. Machicoane, F. Marti, L. Tobos
NSCL, East Lansing, Michigan, USA

Space charge compensation* due to the interaction of the beam with residual gas molecules is a well-known phenomenon for high current injector beam lines. For beam lines using mostly magnetic focusing elements and for pressure above 10^-6 mbar, full neutralization has been observed. However, due to the low pressure required for the efficient transport of high charge state ions, beams in ECR injector lines are typically only partly neutralized. With the performance increase of the next generation ECR ion sources it is possible to extract tens of mA of beam current. In this high current regime, non-linear focusing effects due to the space-charge potential of the beam become more and more important. In order to develop a realistic simulation model for low energy beam transport lines, it is important to estimate the degree of space charge compensation. In this contribution we report on measurements of the beam potential (and neutralization), performed after the extraction region of the ECR ion source, in dependence of the base pressure in the beam line and other source parameters using a Retarding Field Analyzer (RFA). Results are discussed and compared to simulations.
* When the beam interacts with the residual gas, electrons are separated from gas molecules and accumulate inside the beam envelope, thereby compensating the space-charge (aka neutralization)

Slides TUZO04 [4.192 MB]