Bounds on the tau and muon neutrino vector and axial vector charge radius
نویسندگان
چکیده
A Majorana neutrino is characterized by just one flavor diagonal electromagnetic form factor: the anapole moment, that in the static limit corresponds to the axial vector charge radius 〈 r2 A 〉 . Experimental information on this quantity is scarce, especially in the case of the tau neutrino. We present a comprehensive analysis of the available data on the single photon production process e+e− → νν̄γ off Z-resonance, and we discuss the constraints that these measurements can set on 〈 r2 A 〉 for the τ neutrino. We also derive limits for the Dirac case, when the presence of a vector charge radius 〈 r2 V 〉 is allowed. Finally, we comment on additional experimental data on νμ scattering from the NuTeV and CHARM-II collaborations, and estimate the limits implied for 〈 r2 A 〉
منابع مشابه
On the neutrino vector and axial vector charge radius
A Majorana neutrino is characterized by just one flavor diagonal electromagnetic form factor: the anapole moment, that in the static limit corresponds to the axial vector charge radius 〈 r2 A 〉 . As is the case for the vector charge radius of a Dirac neutrino, proving that this quantity is a well defined physical quantity is non trivial. I will first describe briefly the origin of the long stan...
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