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arXiv · 0707.4319

Improved limit on electron neutrino charge radius through a new evaluation of the weak mixing angle

J. Barranco·O. G. Miranda·T. I. Rashba
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Abstract

We have obtained a new limit on the electron neutrino effective charge radius from a new evaluation of the weak mixing angle by a combined fit of all electron-(anti)neutrino electron elastic scattering measurements. Weak mixing angle is found to be sin^2 theta_W=0.259 \pm 0.025 in the low energy regime below 100 MeV. The electron neutrino charge radius squared is bounded to be in the range -0.13 10^-32 cm^2 < r^2 < 3.32 10^-32 cm^2 at 90 % C.L. Both results improve previously published analyses. We also discuss perspectives of future experiments to improve these constraints.

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J. Barranco, O. G. Miranda, T. I. Rashba. 2008-04-22. Improved limit on electron neutrino charge radius through a new evaluation of the weak mixing angle. https://doi.org/10.1016/j.physletb.2008.03.039

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