https://doi.org/10.1140/epjc/s10052-025-13908-5
Regular Article - Theoretical Physics
Malaphoric 
models for 
anomalies
DAMTP, University of Cambridge, Wilberforce Road, CB3 0WA, Cambridge, UK
Received:
12
November
2024
Accepted:
6
February
2025
Published online:
17
February
2025
We study some phenomenological effects of kinetic mixing between the hypercharge field and a new U(1) gauge field in specific models that ameliorate the tensions between measurements and Standard Model predictions in 
decays. To this end, we rederive the dimension-6 SMEFT coefficients resulting from integrating out the kinetically-mixed (‘malaphoric’) field. The kinetic mixing provides a family-universal component to the couplings of the field, which can improve fits to lepton flavour universality observables. We show how kinetic mixing improves the best fit of the 
model to 
data by 7.0 units of 
while remaining compatible with other relevant data sets such as electroweak precision observables and measurements of 
at LEP2.
© The Author(s) 2025
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Funded by SCOAP3.
