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arXiv · 2412.01759

Linear Standard Model extensions in the SMEFT at one loop and Tera-Z

John Gargalionis·Jérémie Quevillon·Pham Ngoc Hoa Vuong·Tevong You
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Abstract

Linear Standard Model (SM) extensions, defined as new particles that can couple linearly to SM fields, form a motivated and finite set of simplified models for exploring phenomenology Beyond the SM (BSM). Heavy BSM particles may be integrated out to obtain their low-energy effects in the SM Effective Field Theory (SMEFT) parametrised by the Wilson coefficients of higher-dimensional operators. We compute and map the dimension-6 SMEFT operator structure of all scalar and fermion linear SM extensions up to one-loop order, thus extending the existing tree-level dictionary of results. Explicit analytic matching expressions for the Wilson coefficients are provided as both Python and Mathematica code in a GitHub repository accessible through links embedded in our main table for each coefficient and within a Python package. We apply our map to highlight the sensitivity to heavy new physics of a $Z$-pole run at a future Tera-$Z$ factory; at one loop, with unit couplings, all linear SM extensions can be indirectly probed by electroweak precision measurements up to $\mathcal{O}(10)$ TeV.

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John Gargalionis, Jérémie Quevillon, Pham Ngoc Hoa Vuong, Tevong You. 2024-12-02. Linear Standard Model extensions in the SMEFT at one loop and Tera-Z. https://arxiv.org/abs/2412.01759

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