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arXiv · 1501.07785

Renormalization group invariant of lepton Yukawa couplings

Takanao Tsuyuki
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Abstract

By using quark Yukawa matrices only, we can construct renormalization invariants that are exact at the one-loop level in the standard model. One of them $I^q$ is accidentally consistent with unity, even though quark masses are strongly hierarchical. We calculate a lepton version of the invariant $I^l$ for Dirac and Majorana neutrino cases and find that $I^l$ can also be close to unity. For the Dirac neutrino and inverted hierarchy case, if the lightest neutrino mass is 3.0 meV to 8.8 meV, an equality $I^q=I^l$ can be satisfied. These invariants are not changed even if new particles couple to the standard model particles, as long as those couplings are generation independent.

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Takanao Tsuyuki. 2015-04-20. Renormalization group invariant of lepton Yukawa couplings. https://doi.org/10.1103/physrevd.91.076004

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