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arXiv · hep-ph/9508404

Top-bottom doublet in the sphaleron background

J. M. Moreno·D. H. Oaknin·M. Quirós
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Abstract

We consider the top-bottom doublet in the background of the sphaleron for the realistic case of large non-degeneracy of fermion masses, in particular $m_b=5$ GeV and $m_t=175$ GeV. We propose an axially symmetric $(r,θ)$-dependent ansatz for fermion fields and investigate the effects of the non-degeneracy on them. The exact solution is described, with an error less than 0.01\%, by a set of ten radial functions. We also propose an approximate solution, in the $m_b/m_t\rightarrow 0$ limit, with an error ${\cal O}(m_b/m_t)$. We have found that the effects of non-degeneracy provide a $θ$-dependence typically $\sim 10\%$.

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J. M. Moreno, D. H. Oaknin, M. Quirós. 1995-08-30. Top-bottom doublet in the sphaleron background. https://doi.org/10.1016/0370-2693(95)01183-q

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