First Leptophobic Dark Matter Search from the Coherent-CAPTAIN-Mills Liquid Argon Detector

Area of Science:

• Particle Physics
• Cosmology
• Astrophysics

Background:

• Dark matter (DM) remains a significant mystery in cosmology.
• Leptophobic dark matter models propose a new interaction portal.
• Liquid argon detectors offer unique capabilities for DM detection.

Purpose of the Study:

• To report the first search results for leptophobic dark matter using the Coherent-CAPTAIN-Mills (CCM) detector.
• To constrain light dark matter models with a baryonic vector portal.
• To establish sensitivity to unexplored parameter space.

Main Methods:

• Utilized a 10-ton liquid argon (LAr) detector (CCM) for a light-based search.
• Employed coherent elastic scattering off argon nuclei to detect dark matter.
• Analyzed data from an engineering run with 17.9×10^20 protons on target (POT).

Main Results:

• Achieved sensitivity to unexplored parameter space for light, leptophobic dark matter.
• Observed 115,005+16.5 events, consistent with background expectations.
• Excluded dark matter masses between 9 MeV and 50 MeV (at 90% C.L.) for a benchmark model.

Conclusions:

• The initial CCM engineering run successfully constrained leptophobic dark matter models.
• Future upgraded runs will probe remaining parameter space and explore other models.
• CCM demonstrates potential as a sensitive dark matter detection experiment.