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High Energy Physics Seminar

Monday, May 8, 2023
4:00pm to 5:00pm
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Matching Effective Theories Efficiently (Matchete) and dealing with evanescent operators
Julie Pages, UC San Diego,

Due to the large scale separations involved, matching is an essential laborious step in the computations to compare high-energy new physics models with experimental data.

Matchete is a Mathematica package that automates the one-loop matching from any generic ultraviolet (UV) model to a low-energy effective field theory (EFT) including, but not limited to, SMEFT. The program takes as input a UV Lagrangian, integrates out heavy degrees of freedom using functional methods, and returns an EFT Lagrangian. The output is further reduced to a minimal basis using integration by parts, simplification of Dirac and group structures, field redefinitions and Fierz identities. A subtlety arise in the treatment of evanescent operators during the basis reduction. We propose an ‘evanescent-free' scheme where the effects of these evanescent operators are taken into account by shifts of the Wilson coefficients, after which they can be safely removed from the basis. After reviewing the theory of functional matching, I will demonstrate the capabilities of the package with a concrete example

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