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arXiv · 1811.03395

Exploratory study of the off-shell properties of the weak vector bosons

Axel Maas·Sebastian Raubitzek·Pascal Törek
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Abstract

Gauge invariance requires even in the weak interactions that physical, observable particles are described by gauge-invariant composite operators. Such operators have the same structure as those describing bound states, and consequently the physical versions of the $W^\pm$, the $Z$, and the Higgs should have some kind of substructure. To test this consequence, we use lattice gauge theory to study the physical weak vector bosons off-shell, especially their form-factor and weak radius, and compare the results to the ones for the elementary particles. We find that the physical particles show substantial deviations from the structure of a point-like particle. At the same time the gauge-dependent elementary particles exhibit unphysical behavior.

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Axel Maas, Sebastian Raubitzek, Pascal Törek. 2018-11-08. Exploratory study of the off-shell properties of the weak vector bosons. https://doi.org/10.1103/physrevd.99.074509

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