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arXiv · 0906.1926

GEMMA experiment: three years of the search for the neutrino magnetic moment

Abstract

The result of the 3-year neutrino magnetic moment measurement at the Kalinin Nuclear Power Plant with the GEMMA spectrometer is presented. Antineutrino-electron scattering is investigated. A high-purity germanium detector of 1.5 kg placed at a distance of 13.9 m from the 3 GW(th) reactor core is used in the spectrometer. The antineutrino flux is 2.7E13 1/scm/s. The differential method is used to extract (nu-e) electromagnetic scattering events. The scattered electron spectra taken in 5184+6798 and 1853+1021 hours for the reactor ON and OFF periods are compared. The upper limit for the neutrino magnetic moment < 3.2E-11 Bohr magneton at 90% CL is derived from the data processing.

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A. G. Beda, V. B. Brudanin, E. V. Demidova, V. G. Egorov, D. V. Medvedev, M. V. Shirchenko, A. S. Starostin, Ts. Vylov. 2009-06-10. GEMMA experiment: three years of the search for the neutrino magnetic moment. https://doi.org/10.1134/s1547477110060063

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