A bstract We present a supersymmetric extension of the Standard Model in which the new physics contributions to the anomalous magnetic moment of the muon can be more than an order of magnitude larger than in the minimal supersymmetric Standard Model. The extended electroweak symmetry breaking sector of the model can consistently accommodate Higgs bosons and Higgsinos with O (1) couplings to muons. We find that sleptons with masses in the multi-TeV range can comfortably explain the recently confirmed discrepancy in the anomalous magnetic moment of the muon. We discuss additional phenomenological aspects of the model, including its effects on tau flavor changing decays.
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Towards TeV-scale supersymmetric electroweak baryogenesis
A bstract Electroweak baryogenesis (EWBG) offers a compelling narrative for the generation of the baryon asymmetry, however it cannot be realised in the Standard Model, and leads to severe experimental tensions in the Minimal Supersymmetric Standard Model (MSSM). One of the reasons for these experimental tensions is that in traditional approaches to EWBG new physics is required to enter at the electroweak phase transition, which conventionally is fixed near 100 GeV. Here we demonstrate that the addition of sub-TeV fields in supersymmetric extensions of the Standard Model permits TeV-scale strongly first-order electroweak phase transition. While earlier literature suggested no-go arguments with regards to high-temperature symmetry breaking in supersymmetric models, we show these can be evaded by employing a systematic suppression of certain thermal corrections in theories with a large number of states. The models presented push the new physics needed for EWBG to higher scales, hence presenting new parameter regions in which to realize EWBG and evade experimental tensions, however they are not expected to render EWBG completely outside of the foreseeable future experimental reach.
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- Award ID(s):
- 2209998
- PAR ID:
- 10432292
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Volume:
- 2023
- Issue:
- 2
- ISSN:
- 1029-8479
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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