Kinetic study of the secondary plasma created in the ITER neutraliser

Journal Article · Thu Mar 12 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3112534· OSTI ID:21269120

Dure, F; Lifschitz, A; Bretagne, J; Maynard, G; Katsonis, K; Minea, T ^[1]; Simonin, A ^[2]

---

1. LPGP, CNRS-Universite Paris Sud, Orsay (France)
2. DRFC, CEA Cadarache, 13108 Saintt-Paul lez Durance (France)

The properties of the secondary plasma created inside the ITER Neutral Beam Injector (NBI) neutraliser, through the interaction of the high energetic hydrogen beam with the molecular hydrogen gas, have been analysed. Starting from the results of our OBI-2 PIC Monte-Carlo numerical code, detailed kinetic of the hydrogen plasma has been studied using a Collisional-Radiative model. In this model, the electron distribution function is determined by solving a Boltzmann equation, whereas main plasma species are derived from balance equations. This paper presents preliminary results obtained in a 0D geometry, boundary conditions bing introduced through effective rates for gain and loss of particles at the neutraliser walls. It has been found that the main ion specie is H{sub 2}{sup +}, essentially coming from the ionisation of the target gas. The electron energy distribution function is not maxwellian and its mean energy is about 5 eV. The plasma-wall interactions yield a strong contribution, in particular regarding the density of molecular ion H{sub 3}{sup +}. Assuming several independent slices of plasma along the negative ions beam axis, the axial profile of the secondary plasma has been analysed. It has been found that the density and mean energy profiles of the plasma electrons are directly related to the plasma potential profile, which in turn closely follows the gas density one.

• OSTI ID: 21269120
• Journal Information: AIP Conference Proceedings, Vol. 1097, Issue 1; Conference: 1. international symposium on negative ions, beams and sources, Aix-en-Provence (France), 9-12 Sep 2008; Other Information: DOI: 10.1063/1.3112534; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANIONS
BOLTZMANN EQUATION
BOUNDARY CONDITIONS
DISTRIBUTION FUNCTIONS
ELECTRONS
ENERGY SPECTRA
EV RANGE 01-10
GEOMETRY
HYDROGEN
HYDROGEN IONS 2 PLUS
HYDROGEN IONS 3 PLUS
ION BEAMS
IONIZATION
ITER TOKAMAK
MONTE CARLO METHOD
PLASMA
PLASMA BEAM INJECTION
PLASMA POTENTIAL
WALL EFFECTS