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arXiv · 1707.09960

Standard Model with a Complex Scalar Singlet: Cosmological Implications and Theoretical Considerations

Cheng-Wei Chiang·Michael J. Ramsey-Musolf·Eibun Senaha
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Abstract

We analyze the theoretical and phenomenological considerations for the electroweak phase transition and dark matter in an extension of the Standard Model with a complex scalar singlet (cxSM). In contrast with earlier studies, we use a renormalization group improved scalar potential and treat its thermal history in a gauge invariant manner. We find that the parameter space consistent with a strong first order electroweak phase transition (SFOEWPT) and present dark matter phenomenological constraints is significantly restricted compared to results of a conventional, gauge non-invariant analysis. In the simplest variant of the cxSM, recent LUX data and a SFOEWPT require a dark matter mass close to half the mass of the Standard Model-like Higgs boson. We also comment on various caveats regarding the perturbative treatment of the phase transition dynamics.

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Cheng-Wei Chiang, Michael J. Ramsey-Musolf, Eibun Senaha. 2017-07-31. Standard Model with a Complex Scalar Singlet: Cosmological Implications and Theoretical Considerations. https://doi.org/10.1103/physrevd.97.015005

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