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New Limit on Axionlike Dark Matter Using Cold Neutrons.
Ivo Schulthess1, Estelle Chanel1, Anastasio Fratangelo1
1Laboratory for High Energy Physics and Albert Einstein Center for Fundamental Physics, University of Bern, 3012 Bern, Switzerland.
Physical Review Letters
|November 18, 2022
Summary
Researchers searched for axionlike particles (ALPs), a dark matter candidate, using cold neutrons. No signal was detected, leading to new constraints on ALP-gluon couplings in a specific mass range.
Area of Science:
- Particle Physics
- Cosmology
- Astrophysics
Background:
- Axionlike particles (ALPs) are hypothetical particles proposed as a potential dark matter candidate.
- The coupling between ALPs and gluons could induce a detectable oscillating signal in a neutron electric dipole moment.
Purpose of the Study:
- To search for evidence of dark matter axionlike particles (ALPs) by looking for their predicted signature.
- To constrain the coupling strength of ALPs to gluons based on experimental data.
Main Methods:
- Utilized a Ramsey-type apparatus with cold neutrons to search for ALP signals.
- Analyzed 24 hours of experimental data across a frequency range from 23 μHz to 1 kHz.
Main Results:
- No significant oscillating signal indicative of ALP-gluon coupling was observed.
- Established new upper limits on the coupling of ALPs to gluons.
Conclusions:
- The experiment provides stringent constraints on the ALP-gluon coupling, particularly in the mass range of 2×10⁻¹⁷ to 2×10⁻¹⁴ eV.
- The findings contribute to the ongoing search for dark matter and understanding fundamental particle physics.
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