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arXiv · 1811.01868

First Commissioning Results of the Multicusp Ion Source at MIT (MIST-1) for H$_2^+$

Daniel Winklehner·Spencer Axani·Patrick Bedard·Janet Conrad·Jesus Corona·Frances Hartwell·Joseph Smolsky·Aashish Tripathee·Loyd Waites·Philip Weigel·Thomas Wester·Maria Yampolskaya
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Abstract

IsoDAR is an experiment under development to search for sterile neutrinos using the isotope Decay-At-Rest (DAR) production mechanism, where protons impinging on $^9$Be create neutrons which capture on $^7$Li which then beta-decays producing $\bar{\nu}_e$. As this will be an isotropic source of $\bar{\nu}_e$, the primary driver current must be large (10 mA cw) for IsoDAR to have sufficient statistics to be conclusive within 5 years of running. H$_2^+$ was chosen as primary ion to overcome some of the space-charge limitations during low energy beam transport and injection into a compact cyclotron. The H$_2^+$ will be stripped into protons before the target. At MIT, a multicusp ion source (MIST-1) was designed and built to produce a high intensity beam with a high H$_2^+$ fraction. MIST-1 is now operational at the Plasma Science and Fusion Center (PSFC) at MIT and under commissioning.

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Daniel Winklehner, Spencer Axani, Patrick Bedard, Janet Conrad, Jesus Corona, Frances Hartwell, Joseph Smolsky, Aashish Tripathee, Loyd Waites, Philip Weigel, Thomas Wester, Maria Yampolskaya. 2018-11-05. First Commissioning Results of the Multicusp Ion Source at MIT (MIST-1) for H$_2^+$. https://doi.org/10.1063/1.5053263

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