Nuclear beta decay with Lorentz violation

TL;DR

This paper investigates potential Lorentz-invariance violations in nuclear beta decay by modifying the W-boson propagator, deriving theoretical expressions, and setting experimental bounds on Lorentz-violating parameters.

Contribution

It introduces a general framework for incorporating Lorentz violation into weak decay processes and derives bounds from experimental data.

Findings

Bounds on Lorentz-violating parameters of order 10^(-6)-10^(-8)

Expression for first-forbidden beta decay transition with spin change of two

Framework for testing Lorentz invariance in weak decays

Abstract

We consider the possibility of Lorentz-invariance violation in weak-decay processes. We present a general approach that entails modifying the W-boson propagator by adding a Lorentz-violating tensor to it. We describe the effects of Lorentz violation on nuclear beta decay in this scenario. In particular we show the expression for a first-forbidden transition with a spin change of two. Using data from an old experiment on the rotational invariance of yttrium-90, we derive several bounds on the Lorentz-violating parameters of the order of 10^(-6)-10^(-8).