Electroweak two-loop contribution to the mass splitting within a new heavy SU(2)$_L$ fermion multiplet
High Energy Physics - Phenomenology
2009-12-22 v2
Abstract
New heavy particles in an SU(2)_L multiplet, sometimes introduced in extensions of the standard model, have highly degenerate tree-level mass M if their couplings to the Higgs bosons are very small or forbidden. However, loop corrections may generate the gauge-symmetry-breaking mass splitting within the multiplet, which does not vanish in the large M limit due to the threshold singularity. We calculate the electroweak contribution to the mass splitting for a heavy fermion multiplet, to the two-loop order. Numerically, two-loop electroweak contributions are typically O(MeV).
Keywords
Cite
@article{arxiv.0906.5207,
title = {Electroweak two-loop contribution to the mass splitting within a new heavy SU(2)$_L$ fermion multiplet},
author = {Youichi Yamada},
journal= {arXiv preprint arXiv:0906.5207},
year = {2009}
}
Comments
14 pages, style changed, analytic forms of two-loop functions added