Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce

Kleinjan, David William

doi:10.1109/PPPS34859.2019.9009880

Title: Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce

Abstract

The Multi-cusp Cesiated Surface Conversion H^- Ion Source at the Los Alamos Neutron Science Center (LANSCE) has provided beam at ~14 mA, 120 Hz, and 10% D.F. for many years of neutron science research. Recently, random high current transients were discovered in the arc current used to ionize hydrogen in the LANSCE H^- ion source, and in the convertor current used to convert protons to H- ions. Most have no effect, but more severe transients can cripple beam output. Hypothesized causes are related to cesiation effects, plasma instabilities, tungsten filament evaporation/sputtering, or from the arc modulator circuitry. A dedicated study was recently done on the LANSCE H^- Ion source test stand to determine the cause of these transients. Current understanding indicates that the more severe transients come from a combination of cesiation effects and plasma instabilities. The status of these current transient studies on the LANSCE H^- ion source will be discussed.

Authors:

^[1]

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

Publication Date:: Sat Jun 01 00:00:00 EDT 2019

Research Org.:: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1623424

Report Number(s):: LA-UR-19-21515
Journal ID: ISSN 2158-4915; TRN: US2106877

Grant/Contract Number:: 89233218CNA000001

Resource Type:: Accepted Manuscript

Journal Name:: IEEE Pulsed Power Conference

Additional Journal Information:: Journal Volume: 2019; Conference: 2019 IEEE Pulsed Power & Plasma Science (PPPS), Orlando, FL, United States, 23-29 Jun 2019; Journal ID: ISSN 2158-4915

Publisher:: IEEE

Country of Publication:: United States

Language:: English

Subject:: 43 PARTICLE ACCELERATORS; Accelerator Design, Technology, and Operations

Citation Formats


                    Kleinjan, David William. Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce.  United States: N. p., 2019. 
Web.  doi:10.1109/PPPS34859.2019.9009880.

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                    Kleinjan, David William. Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce.  United States.  https://doi.org/10.1109/PPPS34859.2019.9009880

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                    Kleinjan, David William. Sat .  
"Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce".  United States.  https://doi.org/10.1109/PPPS34859.2019.9009880.  https://www.osti.gov/servlets/purl/1623424.

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@article{osti_1623424,

  title        = {Transients on arc and Convertor Currents in the Multi-Cusp Cesiated Surface Conversion H-Ion Source at Lansce},

  author       = {Kleinjan, David William},

  abstractNote = {The Multi-cusp Cesiated Surface Conversion H- Ion Source at the Los Alamos Neutron Science Center (LANSCE) has provided beam at ~14 mA, 120 Hz, and 10% D.F. for many years of neutron science research. Recently, random high current transients were discovered in the arc current used to ionize hydrogen in the LANSCE H- ion source, and in the convertor current used to convert protons to H- ions. Most have no effect, but more severe transients can cripple beam output. Hypothesized causes are related to cesiation effects, plasma instabilities, tungsten filament evaporation/sputtering, or from the arc modulator circuitry. A dedicated study was recently done on the LANSCE H- Ion source test stand to determine the cause of these transients. Current understanding indicates that the more severe transients come from a combination of cesiation effects and plasma instabilities. The status of these current transient studies on the LANSCE H- ion source will be discussed.},

  doi          = {10.1109/PPPS34859.2019.9009880},

  journal      = {IEEE Pulsed Power Conference},

  number       = ,

  volume       = 2019,

  place        = {United States},

  year         = {Sat Jun 01 00:00:00 EDT 2019},

  month        = {Sat Jun 01 00:00:00 EDT 2019}

}

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Figure 1: A side view of the LANSCE H- ion source. Explanation given in the text.

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