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Large bulk matter search for fractional charge particles

Irwin Lee
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Abstract

We have carried out the largest search for stable particles with fractional electric charge, based on an oil drop method that incorporates a horizontal electric field and upward air flow. No evidence for such particles was found, giving a 95% C.L. upper limit of $1.15\times 10^{-22}$ particles per nucleon on the abundance of fractional charge particles in silicone oil for $0.18 e \le |Q_{residual}| \le 0.82 e$.

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Irwin Lee. 2002-09-23. Large bulk matter search for fractional charge particles. https://arxiv.org/abs/hep-ex/0209060

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