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arXiv · 1512.05786

Potential of a singlet scalar enhanced Standard Model

Abstract

We investigate the parameter space of the Standard Model enhanced by a gauge singlet real scalar $S$. Taking into account all the theoretical and experimental constraints, we show the allowed parameter space for two different types of such singlet-enhanced Standard Model. For the first case, the scalar potential has an explicit $Z_2$-symmetry, and may lead to a dark matter candidate under certain conditions. For the second case, the scalar potential does not respect any $Z_2$. This is again divided into two subcategories: one where the Standard Model vacuum is stable, and one where it is unstable and can decay into a deeper minimum. We show how the parameters in the scalar potential control the range of validity of all these models. Finally, we show the effect of one-loop correction on the positions and depths of the minima of the potential.

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Swagata Ghosh, Anirban Kundu, Shamayita Ray. 2015-12-17. Potential of a singlet scalar enhanced Standard Model. https://doi.org/10.1103/physrevd.93.115034

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