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Search for Axionlike and Scalar Particles with the NA64 Experiment.
D Banerjee1,2, J Bernhard1, V E Burtsev3
1CERN, European Organization for Nuclear Research, CH-1211 Geneva, Switzerland.
Physical Review Letters
|September 10, 2020
Summary
Researchers searched for new light particles called axionlike particles using a high-energy electron beam. No evidence was found, leading to new limits on their properties and interactions with photons.
Area of Science:
- Particle Physics
- High-Energy Physics
- Experimental Physics
Background:
- Axionlike particles are hypothetical particles that interact with photons.
- The Primakoff effect provides a mechanism for producing axionlike particles from photon interactions.
Purpose of the Study:
- To conduct a model-independent search for light scalar and pseudoscalar axionlike particles.
- To probe axionlike particle parameter space inaccessible to previous experiments.
Main Methods:
- Utilized a 100 GeV electron beam at the CERN SPS H4 facility.
- Searched for axionlike particles produced via the Primakoff effect in an active dump.
- Detected axionlike particles through their decay into two photons or via missing energy signatures.
Main Results:
- Analyzed data from 2.84×10^11 electrons on target.
- No evidence for the production or decay of light axionlike particles was observed.
- Established new limits on the axionlike particle-photon coupling strength for masses below 55 MeV.
Conclusions:
- The experiment sets stringent new limits on the properties of light axionlike particles.
- The findings constrain axionlike particle models and guide future searches.
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