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Title: Proposal for a Ramsey Neutron-Beam Experiment to Search for Ultralight Axion Dark Matter at the European Spallation Source
High-intensity neutron beams, such as those available at the European Spallation Source (ESS), provide new opportunities for fundamental discoveries. Here, we discuss a novel Ramsey neutron-beam experiment to search for ultralight axion dark matter through its coupling to neutron spins, which would cause the neutron spins to rotate about the velocity of the neutrons relative to the dark matter halo. We estimate that experiments at the HIBEAM beamline with a 50 m free flight path at the ESS can improve the sensitivity to the axion-neutron coupling compared to the current best laboratory limits by up to 2–3 orders of magnitude over the axion mass range 10 22 eV 10 16 eV . Published by the American Physical Society2024  more » « less
Award ID(s):
2209481
PAR ID:
10613181
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review Letters
Volume:
133
Issue:
18
ISSN:
0031-9007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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