A study of the optical effect of plasma sheath in a negative ion source using IBSIMU code

Anand George; Taneli Kalvas; Stephane Melanson; Nicolas Savard; Dave Potkins; Morgan Dehnel; Neil G R Broderick

doi:10.1063/1.5129603

A study of the optical effect of plasma sheath in a negative ion source using IBSIMU code

Rev Sci Instrum. 2020 Jan 1;91(1):013306. doi: 10.1063/1.5129603.

Authors

Anand George¹, Taneli Kalvas², Stephane Melanson³, Nicolas Savard³, Dave Potkins³, Morgan Dehnel³, Neil G R Broderick¹

Affiliations

¹ Department of Physics, University of Auckland, Private Bag 92019 Auckland, New Zealand.
² Department of Physics, University of Jyväskylä, P.O. Box 35, Jyväskylä 40014, Finland.
³ D-Pace, 625 Front St. 305, Nelson, British Columbia V1L 4B6, Canada.

PMID: 32012600
DOI: 10.1063/1.5129603

Abstract

A plasma sheath inside an ion source has a strong focusing effect on the formation of an ion beam from the plasma. Properties of the beam depend on the shape and location of the plasma sheath inside the source. The most accessible experimental data dependent on the plasma sheath are the beam phase space distribution. Variation of beam emittance is a reflection of the properties of the plasma sheath, with minimum emittance for the optimal shape of the plasma sheath. The location and shape of the plasma sheath are governed by complex physics and can be understood by simulations using plasma models in particle tracking codes like IBSimu. In the current study, a model of the D-Pace's TRIUMF licensed filament powered volume-cusp negative ion source is made using the IBSimu code. Beam emittance trends are compared between experiments and simulations.