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Dark Matter Search in Missing Energy Events with NA64
D Banerjee1,2, V E Burtsev3, A G Chumakov4
1CERN, European Organization for Nuclear Research, CH-1211 Geneva, Switzerland.
Physical Review Letters
|October 22, 2019
Summary
The NA64 experiment searched for dark matter particles using electron interactions but found no evidence. This study sets new limits on dark matter interactions and highlights the effectiveness of active beam dump experiments.
Area of Science:
- Particle Physics
- Cosmology
- Experimental Physics
Background:
- Dark matter remains one of the biggest mysteries in physics.
- A new vector boson, the dark photon (A'), is a potential mediator for dark matter interactions.
- Sub-GeV dark matter is particularly challenging to detect.
Purpose of the Study:
- To search for sub-GeV dark matter production via dark photon mediation.
- To analyze missing energy events from high-energy electron interactions.
- To constrain the parameter space of dark matter models.
Main Methods:
- Utilized the NA64 experiment at the CERN Super Proton Synchrotron (SPS).
- Analyzed data from 100 GeV electron interactions in an active beam dump.
- Searched for missing energy signatures indicative of dark matter production.
Main Results:
- No evidence for dark matter production mediated by a dark photon was found.
- Collected data from 2016-2018 with 2.84 x 10^11 electrons on target.
- Derived the most stringent constraints to date on the dark photon's mixing strength with photons.
Conclusions:
- The active beam dump approach is a powerful method for dark matter searches.
- New limits are placed on dark matter models in the sub-GeV mass range (≲0.2 GeV).
- Further research can explore different mass ranges and mediator particles.
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