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Title: Search for axionlike dark matter using liquid-state nuclear magnetic resonance
We search for dark matter in the form of axionlike particles (ALPs) in the mass range 5.576741 neV / c 2 5.577733 neV / c 2 by probing their possible coupling to fermion spins through the ALP field gradient. This is achieved by performing proton nuclear magnetic resonance spectroscopy on a sample of methanol as a technical demonstration of the Cosmic Axion Spin Precession Experiment Gradient (CASPEr-Gradient) Low-Field apparatus. Searching for spin-coupled ALP dark matter in this mass range with associated Compton frequencies in a 240 Hz window centered at 1.348570 MHZ resulted in a sensitivity to the ALP-proton coupling constant of g ap 3 × 10 2 GeV 1 . This narrow-bandwidth search serves as a proof-of-principle and a commissioning measurement, validating our methodology and demonstrating the experiment’s capabilities. CASPEr-Gradient Low-Field will probe the mass range from 4.1 peV / c 2 to 17    neV / c 2 with hyperpolarized samples to boost the sensitivity beyond the astronomical limits.  more » « less
Award ID(s):
2110388 2145162
PAR ID:
10652417
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review D
Volume:
112
Issue:
5
ISSN:
2470-0010
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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