Cyclotrons2013 - List of Authors (Mironov, V.)

Paper

Title

Page

PIC Simulations of Ion Dynamics in ECR Ion Sources

134

V. Mironov, J.P.M. Beijers
KVI, Groningen, The Netherlands

To better understand the physical processes in ECRIS plasmas, we developed a Particle-in-Cell code that follows the ionization and diffusion dynamics of ions. The basic features of the numerical model are given elsewhere*. Electron temperature is a free parameter and we found that its value should be about 1 keV to reproduce the experimentally observed performance of our 14 GHz ECR source. We assume that a pre-sheath is located outside the ECR zone, in which ion acceleration toward the walls occurs. Electric fields inside the ECR zone are assumed to be zero. The ion production is modelled assuming ion confinement by a ponderomotive barrier formed at the boundary of the ECR zone. The barrier height is defined by the RF radiation density at the electron resonance layer and is taken as an adjustable parameter. With these assumptions, we are able to reproduce the main features of ECRIS performance, such as saturation and decrease of highest charge state currents with increasing gas pressure, as well as reaction to an increase of injected RF power. Study of the source response to variations of the source parameters is possible.
*V. Mironov and J. P. M. Beijers, “Three-dimensional simulations of ion dynamics in the plasma of an electron cyclotron resonance ion source”, Phys. Rev. ST Accel. Beams 12, 073501 (2009).

Slides TU1PB03 [18.160 MB]

WEPPT009

Transverse Phase-Space Distributions of Low Energy Ion Beams Extracted from an ECR Ion Source

341

S. Saminathan
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
J.P.M. Beijers, S. Brandenburg, H.R. Kremers, V. Mironov
KVI, Groningen, The Netherlands

Transverse phase-space distributions of low-energy ion beams extracted from ECR ion sources often show higher-order effects caused by ion-optical aberrations. Understanding these effects is mandatory to keep emittance growth and the resulting beam losses in low-energy beam transport lines under control. We present the results of an experimental and theoretical study of beam extraction and transport in the AGOR injection line at KVI. Particle tracking simulations have been performed of a multi-component neon ion beam extracted from an ECR ion source to calculate 4D phase-space distributions at various positions along the beamline. The simulations compare well with beam profile and emittance measurements.

Paper	Title	Page
TU1PB03	PIC Simulations of Ion Dynamics in ECR Ion Sources	134
	V. Mironov, J.P.M. Beijers KVI, Groningen, The Netherlands
	To better understand the physical processes in ECRIS plasmas, we developed a Particle-in-Cell code that follows the ionization and diffusion dynamics of ions. The basic features of the numerical model are given elsewhere. Electron temperature is a free parameter and we found that its value should be about 1 keV to reproduce the experimentally observed performance of our 14 GHz ECR source. We assume that a pre-sheath is located outside the ECR zone, in which ion acceleration toward the walls occurs. Electric fields inside the ECR zone are assumed to be zero. The ion production is modelled assuming ion confinement by a ponderomotive barrier formed at the boundary of the ECR zone. The barrier height is defined by the RF radiation density at the electron resonance layer and is taken as an adjustable parameter. With these assumptions, we are able to reproduce the main features of ECRIS performance, such as saturation and decrease of highest charge state currents with increasing gas pressure, as well as reaction to an increase of injected RF power. Study of the source response to variations of the source parameters is possible. V. Mironov and J. P. M. Beijers, “Three-dimensional simulations of ion dynamics in the plasma of an electron cyclotron resonance ion source”, Phys. Rev. ST Accel. Beams 12, 073501 (2009).
	Slides TU1PB03 [18.160 MB]

WEPPT009	Transverse Phase-Space Distributions of Low Energy Ion Beams Extracted from an ECR Ion Source	341
	S. Saminathan TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada J.P.M. Beijers, S. Brandenburg, H.R. Kremers, V. Mironov KVI, Groningen, The Netherlands
	Transverse phase-space distributions of low-energy ion beams extracted from ECR ion sources often show higher-order effects caused by ion-optical aberrations. Understanding these effects is mandatory to keep emittance growth and the resulting beam losses in low-energy beam transport lines under control. We present the results of an experimental and theoretical study of beam extraction and transport in the AGOR injection line at KVI. Particle tracking simulations have been performed of a multi-component neon ion beam extracted from an ECR ion source to calculate 4D phase-space distributions at various positions along the beamline. The simulations compare well with beam profile and emittance measurements.