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arXiv · 1111.4566

Constraining Extra Neutral Gauge Bosons with Atomic Parity Violation Measurements

Abstract

The discovery of a new neutral gauge boson, $Z'$, could provide the first concrete evidence of physics beyond the standard model. We explore how nuclear weak charge measurements in atomic parity violation (APV) experiments can be used to constrain $Z'$ bosons. We use the recent measurement of the $^{133}$Cs nuclear weak charge to estimate lower bounds on the mass of $Z'$ bosons for a number of representative models and to put constraints on the couplings of a newly discovered $Z'$ boson. We also consider how these constraints might be improved by future APV experiments that will measure nuclear weak charges of multiple isotopes. We show how measurements of a single isotope, and combining measurements into ratios and differences, can be used to constrain the couplings of a $Z'$ and discriminate between models. We find that current and future APV experiments could potentially play an important role in unravelling new physics if a $Z'$ were discovered.

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BibTeXRIS

Ross Diener, Stephen Godfrey, Ismail Turan. 2011-11-19. Constraining Extra Neutral Gauge Bosons with Atomic Parity Violation Measurements. https://doi.org/10.1103/physrevd.86.115017

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