How Magnetic is the Neutrino?
Abstract
The existence of a neutrino magnetic moment implies contributions to the neutrino mass via radiative corrections. We derive modelindependent "naturalness" upper bounds on the magnetic moments of Dirac and Majorana neutrinos, generated by physics above the electroweak scale. For Dirac neutrinos, the bound is several orders of magnitude more stringent than present experimental limits. However, for Majorana neutrinos the magnetic moment bounds are weaker than present experimental limits if μ_{ν} is generated by new physics at ~ 1 TeV, and surpass current experimental sensitivity only for new physics scales > 10  100 TeV. The discovery of a neutrino magnetic moment near present limits would thus signify that neutrinos are Majorana particles.
 Publication:

International Journal of Modern Physics A
 Pub Date:
 2007
 DOI:
 10.1142/S0217751X07038256
 arXiv:
 arXiv:0707.1556
 Bibcode:
 2007IJMPA..22.4891B
 Keywords:

 Neutrino;
 magnetic moment;
 neutrino mass;
 High Energy Physics  Phenomenology
 EPrint:
 9 pages, 6 figures. Talk given at Festschrift in honour of B. H. J McKellar and G. C. Joshi