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arXiv · 1810.02356

Reparameterization Invariant Operator Basis for NRQED and HQET

Andrew Kobach·Sridip Pal
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Abstract

We discuss how reparameterization invariance connects a rotationally-invariant heavy particle effective theory with a single fermion to a Lorentz-invariant theory. Using Hilbert-series methods, a Lorentz-invariant operator basis is tabulated, up to and including operators of order $1/M^4$, when the fermion couples to an external $U(1)$ or $SU(3)$ gauge interaction.

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Andrew Kobach, Sridip Pal. 2018-10-04. Reparameterization Invariant Operator Basis for NRQED and HQET. https://doi.org/10.1007/jhep11(2019)012

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