Hot filament performance in a Freeman ion source

Journal Article · 20 September 2018 · AIP Conference Proceedings

DOI: https://doi.org/10.1063/1.5053266 · OSTI ID:1565852

Draganic, Ilija N.  ^[1]; Leibman, Christopher P.  ^[1]; Rybarcyk, Lawrence J.  ^[1]; Bronson, Tyler M. ^[1]; Dudeck, Kevin W. ^[1]

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1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Here, we report on the simulation results of the hot tungsten filament behavior in a Freeman ions source installed in the LANL electro-magnetic isotope separator (EMIS). The Freeman source enables us to ionize and extract high intensity single-charge ion beams from different gases as well as from various solid materials in order to purify the content of a selected isotope. We have modified our LANSCE H– Ion Source Filament Model to calculate the ion source working parameters during a beam production cycle and estimate the ion source filament lifetime. Two main mass erosion processes of the hot cathode in a Freeman ion source are included: thermal evaporation and plasma sputtering. The initial working temperature of the ion source filament was estimated to be in range of 2400 to 2500 K. The filament model shows that the plasma sputtering rate is several magnitude of order higher than the thermal evaporation rate. The results of ion source modeling were compared with recorded data during the EMIS beam production runs using krypton noble gas.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)
• Grant/Contract Number: 89233218CNA000001
• OSTI ID: 1565852
• Report Number(s): LA-UR--17-29242
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Vol. 2011; ISSN 0094-243X
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English