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arXiv · 1410.4193

Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators

Landon Lehman
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Abstract

We present a complete list of the independent dimension-7 operators that are constructed using the Standard Model degrees of freedom and are invariant under the Standard Model gauge group. This list contains only 20 independent operators; far fewer than the 63 operators available at dimension 6. All of these dimension-7 operators contain fermions and violate lepton number, and 7 of the 20 violate baryon number as well. This result extends the Standard Model Effective Field Theory (SMEFT) and allows a more detailed exploration of the structure and properties of possible deformations from the Standard Model Lagrangian.

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Landon Lehman. 2014-12-26. Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators. https://doi.org/10.1103/physrevd.90.125023

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