Perturbative unitarity constraints on generic vector interactions

Daniele Barducci; Marco Nardecchia; Claudio Toni

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arXiv · 2306.11533

Perturbative unitarity constraints on generic vector interactions

Daniele Barducci·Marco Nardecchia·Claudio Toni

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Abstract

We study perturbative unitarity constraints on generic interactions between fermion and vector fields, which are allowed to have generic quantum numbers under a $\prod_i SU(N_i) \otimes U(1)$ group. We derive compact expressions for the bounds on the couplings for the cases where the fields transform under the trivial, fundamental or adjoint representation of the various, considering both the case of a complex vector arbitrary interactions with fermionic current and also the case of vectors arising as gauge fields. We apply our results to some specific NP models showing the constraints that can be derived using the tool of perturbative unitarity.

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Daniele Barducci, Marco Nardecchia, Claudio Toni. 2023-06-20. Perturbative unitarity constraints on generic vector interactions. https://arxiv.org/abs/2306.11533

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