Title :
Simulation and modeling of the Gamble II self-pinched ion beam transport experiment
Author :
Rose, David V. ; Ottinger, P.F. ; Hinshelwood, D.D. ; Mosher, D. ; Myers, Matthew C. ; Neri, J.M. ; Stephanakis, S.J. ; Weber, B.V. ; Young, Frederic ; Welch, Dale R.
Author_Institution :
Div. of Plasma Phys., Naval Res. Lab., Washington, DC, USA
Abstract :
Summary form only given. Progress in numerical simulations and modeling of the self-pinched ion beam transport experiment at the Naval Research Laboratory (NRL) is reviewed. In the experiment, a 1.2-MeV, 100-kA proton beam enters a 1-m long, transport region filled with a low pressure gas (30 250 mTorr helium, or 1 Torr air). The time-dependent velocity distribution function of the injected ion beam is determined from an orbit code that uses a pinch-reflex ion diode model and the measured voltage and current from this diode on the Gamble II generator at NRL. This distribution function is used as the beam input condition for numerical simulations carried out using the hybrid particle-in-cell code IPROP. Results of the simulations will be described, and detailed comparisons will be made with various measurements, including line-integrated electron-density, proton-fluence, and beam radial-profile measurements. As observed in the experiment, the simulations show evidence of self-pinching for helium pressures between 35 and 80 mTorr. Simulations and measurements in 1 Torr air show ballistic transport. The relevance of these results to ion-driven inertial confinement fusion will be discussed.
Keywords :
ion beams; ion sources; pinch effect; plasma diodes; plasma simulation; plasma transport processes; plasma-beam interactions; 1 m; 1 torr; 1.2 MeV; 100 kA; 30 to 250 mtorr; Gamble II self-pinched ion beam transport experiment; IPROP hybrid particle-in-cell code; Naval Research Laboratory; ballistic transport; beam input condition; beam radial-profile measurements; diode current; diode voltage; helium pressures; injected ion beam; ion-driven inertial confinement fusion; line-integrated electron-density; low pressure gas; modeling; orbit code; pinch-reflex ion diode model; proton fluence; time-dependent velocity distribution function; transport region; Current measurement; Diodes; Distribution functions; Extraterrestrial measurements; Helium; Ion beams; Laboratories; Numerical models; Numerical simulation; Particle beams;
Conference_Titel :
Plasma Science, 1999. ICOPS '99. IEEE Conference Record - Abstracts. 1999 IEEE International Conference on
Conference_Location :
Monterey, CA, USA
Print_ISBN :
0-7803-5224-6
DOI :
10.1109/PLASMA.1999.829457