A Novel, Steerable, Low-Energy Proton Source for Detector Characterization

Nicholas Macsai; August Mendelsohn; David Harrison; Russell Mammei; Michael Gericke; Leah Broussard; Erick Smith; Grant Riley; Glenn Randall; Mark Makela

doi:10.1016/j.nima.2026.171336

arXiv · 2510.03654

A Novel, Steerable, Low-Energy Proton Source for Detector Characterization

Nicholas Macsai·August Mendelsohn·David Harrison·Russell Mammei·Michael Gericke·Leah Broussard·Erick Smith·Grant Riley·Glenn Randall·Mark Makela

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Abstract

We report on the conversion of the Manitoba II mass spectrometer into a versatile low-energy proton beam facility. This infrastructure is adaptable to any detector-under-test (DUT), and has proven itself effective with the characterization of silicon detectors used in subatomic beyond-the-StandardModel (BSM) searches, namely the Nab experiment. A pencil beam of monoenergetic protons can be produced in a range from 25 keV to 35 keV, achieving a beamcurrent of ~1x10-18 A. Electrostatic steering plates were constructed to direct the Gaussian-profile proton beam over a 117mm diameter areaof-interest with full-width at half-maxima (FWHM) ranging from 0.6 mm to 1.26 mm. This work discusses the modifications and subsequent tests to confirm the beam specifications met the demands of the aforementioned detectors.

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Nicholas Macsai, August Mendelsohn, David Harrison, Russell Mammei, Michael Gericke, Leah Broussard, Erick Smith, Grant Riley, Glenn Randall, Mark Makela. 2025-10-04. A Novel, Steerable, Low-Energy Proton Source for Detector Characterization. https://doi.org/10.1016/j.nima.2026.171336

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