The effective neutrino charge radius
Abstract
It is shown that at one-loop order a neutrino charge radius (NCR) may be defined, which is ultraviolet finite, does not depend on the gauge-fixing parameter, nor on properties of the target other than its electric charge. This is accomplished through the systematic decomposition of physical amplitudes into effective self-energies, vertices, and boxes, which separately respect electroweak gauge invariance. In this way the NCR stems solely from an effective proper photon-neutrino one-loop vertex, which satisfies a naive, QED-like Ward identity. The NCR so defined may be extracted from experiment, at least in principle, by expressing a set of experimental electron-neutrino cross-sections in terms of the finite NCR and two additional gauge- and renormalization-group-invariant quantities, corresponding to the electroweak effective charge and mixing angle. PACS: 13.15.+g Neutrino interactions - 13.40.Gp Electromagnetic form factors
- Publication:
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European Physical Journal C
- Pub Date:
- 2004
- DOI:
- 10.1140/epjcd/s2003-03-920-7
- arXiv:
- arXiv:hep-ph/0310028
- Bibcode:
- 2004EPJC...33S.865P
- Keywords:
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- High Energy Physics - Phenomenology
- E-Print:
- Talk given at EPS2003 - Aachen, Germany, July 2003