Charge and current neutralization physics of a heavy ion beam during final transport
Heavy ion fusion requires high power to be focussed onto a small pellet. If the reactor chamber pressure is below 10/sup -4/ to 10/sup -5/ Torr, beam compression will be limited by space charge unless neutralized by co-moving electrons. If higher chamber pressures are used, the heavy ion beam will create a significant number of background electrons during its propagation and will undergo stripping. The background electrons could provide the neutralization required for high beam intensities. In this paper we will focus on the physics associated with propagation through a fully ionized hydrogen plasma, so background electron generation is not included. One-dimensional electrostatic and two-dimensional fully electromagnetic particle-in-cell simulations are presented. If a background plasma is present, we find that coinjected electrons whose purpose is to charge and current neutralize the ion beam become two-stream unstable and no longer provide the thermally cool neutralization required. Further, we find that the ion induced background electron temperature is very sensitive to the ion beam to background electron charge density ratio.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 5841526
- Report Number(s):
- LA-UR-86-1810; CONF-860510-5; ON: DE86011243
- Resource Relation:
- Journal Volume: 152; Conference: Symposium on heavy ion inertial fusion, Washington, DC, USA, 27 May 1986; Other Information: Portions of this document are illegible in microfiche products
- Country of Publication:
- United States
- Language:
- English
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