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arXiv · 2312.09099

The oblique parameters from arbitrary new fermions

Francisco Albergaria·Darius Jurčiukonis·Luís Lavoura
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Abstract

We compute the six oblique parameters $S, T, U, V, W, X$ in a New Physics Model with an arbitrary number of new fermions, in arbitrary representations of $SU(2) \times U(1)$, and mixing arbitrarily among themselves. We show that $S$ and $U$ are automatically finite, but $T$ is finite only if there is a specific relation between the masses of the new fermions and the representations of $SU(2) \times U(1)$ that they sit in. We apply our general computation to two illustrative cases.

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Francisco Albergaria, Darius Jurčiukonis, Luís Lavoura. 2023-12-14. The oblique parameters from arbitrary new fermions. https://doi.org/10.1007/jhep05(2024)190

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