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Published on: November 15, 2013
Search for a 33.9 MeV/c(2) neutral particle in pion decay
Physical Review Letters
|September 16, 2000
Summary
The NuTeV experiment searched for a specific neutral particle from pion decay. No evidence was found, setting stringent limits on its existence and potential role in neutrino anomalies.
Area of Science:
- Particle Physics
- Neutrino Physics
- Experimental Physics
Background:
- An anomaly in neutrino interaction timing observed by the KARMEN experiment suggested a possible weakly interacting neutral particle.
- This particle, with a mass of 33.9 MeV/c², could originate from pion decay.
Purpose of the Study:
- To search for the hypothesized weakly interacting neutral particle produced in pion decay.
- To investigate if this particle could explain the KARMEN anomaly.
Main Methods:
- The E815 (NuTeV) experiment utilized an instrumented decay region to detect the particle's decays.
- Searched for evidence of the particle's production from pion decay.
Main Results:
- No evidence for the weakly interacting neutral particle was detected.
- The experiment established sensitivity to pion branching ratios as low as 10⁻¹³.
Conclusions:
- The search found no evidence supporting the existence of the hypothesized particle.
- The results place strong constraints on the particle's properties and its potential explanation for the KARMEN anomaly.
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