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arXiv · 1208.5634

Decays of Fourth Generation Bound States

V. F. Dmitriev·V. V. Flambaum
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Abstract

We consider the decay modes of the heavy $q^\prime\bar{q^\prime}$ bound states originating from Higgs boson exchange between quark -- anti-quark pair. In case of a small coupling between the fourth and lower generation the main decay mode is $q^\prime\bar{q^\prime}$ annihilation. We show that for a vector state the dominant decay modes are Higgs-gamma and Higgs-Z decays, while for a pseudoscalar state the strong two-gluon decay mode dominates. The bound states are very narrow. The ratio of the total width to the binding energy is less than 1% if we are not extremely close to the critical quark mass where the binding energy is very small. The discussed decay modes exist for any fermion-antifermion bound states including heavy leptons and heavy neutrinos if their masses are high enough to form a bound state due to attractive Higgs boson exchange potential.

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V. F. Dmitriev, V. V. Flambaum. 2012-08-28. Decays of Fourth Generation Bound States. https://doi.org/10.1142/s0217751x12501795

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