Model simulations of continuous ion injection into electron-beam ion source trap with slanted electrostatic mirror

Journal Article · Fri Feb 15 00:00:00 EST 2008 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2828061· OSTI ID:21123675

Pikin, A; Kponou, A; Alessi, J G; Beebe, E N; Prelec, K; Raparia, D ^[1]

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1. Brookhaven National Laboratory, Upton, New York 11973 (United States)

The efficiency of trapping ions in an electron-beam ion source (EBIS) is of primary importance for many applications requiring operations with externally produced ions: RIA breeders, ion sources, and traps. At the present time, the most popular method of ion injection is pulsed injection, when short bunches of ions get trapped in a longitudinal trap while traversing the trap region. Continuous trapping is a challenge for EBIS devices because mechanisms which reduce the longitudinal ion energy per charge in a trap (cooling with residual gas, energy exchange with other ions, and ionization) are not very effective, and accumulation of ions is slow. A possible approach to increase trapping efficiency is to slant the mirror at the end of the trap which is opposite to the injection end. A slanted mirror will convert longitudinal motion of ions into transverse motion, and, by reducing their longitudinal velocity, prevent these ions from escaping the trap on their way out. The trade-off for the increased trapping efficiency this way is an increase in the initial transverse energy of the accumulated ions. The slanted mirror can be realized if the ends of two adjacent electrodes, drift tubes, which act as an electrostatic mirror, are machined to produce a slanted gap, rather than an upright one. Applying different voltages to these electrodes will produce a slanted mirror. The results of two-dimensional (2D) and three-dimensional (3D) computer simulations of the ion injection into an EBIS are presented using simplified models of an EBIS with conical (2D simulations) and slanted (3D simulations) mirror electrodes.

• OSTI ID: 21123675
• Journal Information: Review of Scientific Instruments, Vol. 79, Issue 2; Conference: ICIS 2007: 12. international conference on ion sources, Jeju (Korea, Republic of), 26-31 Aug 2007; Other Information: DOI: 10.1063/1.2828061; (c) 2008 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPUTERIZED SIMULATION
DRIFT TUBES
EFFICIENCY
ELECTRIC POTENTIAL
ELECTRODES
ELECTRON BEAM ION SOURCES
ELECTRON BEAMS
ELECTROSTATIC MIRRORS
ELECTROSTATICS
ENERGY TRANSFER
IONS
THREE-DIMENSIONAL CALCULATIONS
TRANSVERSE ENERGY
TRAPPING
TRAPS
TWO-DIMENSIONAL CALCULATIONS