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Search for millicharged particles in reactor neutrino experiments: a probe of the PVLAS anomaly

S. N. Gninenko·N. V. Krasnikov·A. Rubbia
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Abstract

It has been recently suggested that the vacuum magnetic dichroism observed by the PVLAS experiment could be explained by the pair production of a new light, m ~0.1 eV, millicharged, q ~ 3 10^{-6} e, fermions. In addition, it has been pointed out that millicharged particles with q > 10^{-9} e appear naturally in models based on the string theory. We show that low energy reactor neutrino experiments provide a sensitive probe of millicharged particles. Considering, as an example, recent results of the TEXONO experiment searching for neutrino magnetic moment, a new upper bound q < 10^{-5} e for the mass region m < 1 keV is derived. These results enhance motivations for a more sensitive search for such particles in near future experiments. Furthemore, a direct experimental limit on the electric charge of the electron antineutrino q < 3.7 10^{-12} e is obtained.

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S. N. Gninenko, N. V. Krasnikov, A. Rubbia. 2007-03-29. Search for millicharged particles in reactor neutrino experiments: a probe of the PVLAS anomaly. https://doi.org/10.1103/physrevd.75.075014

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