6 papers
Leptophilic New Physics and the Cabibbo Angle Anomaly
Fiona Kirk
The Cabibbo Angle Anomaly, an apparent deficit in first-row CKM unitarity, can be addressed by leptophilic Standard Model extensions that generate new contributions to the Fermi co…
Explaining the Cabibbo Angle Anomaly and Lepton Flavour Universality Violation in Tau Decays With a Singly-Charged Scalar Singlet
Fiona Kirk
The singly charged singlet scalar, with its necessarily flavour violating couplings to leptons, lends itself particularly well for an explanation of the Cabibbo Angle Ano…
Global Analysis of Leptophilic Z' Bosons
Andrzej J. Buras, Andreas Crivellin, Fiona Kirk +2
New neutral heavy gauge bosons () are predicted within many extensions of the Standard Model. While in case they couple to quarks the LHC bounds are very stringent, lepto…
Searching for Lepton Flavour (Universality) Violation and Collider Signals from a Singly-Charged Scalar Singlet
Andreas Crivellin, Fiona Kirk, Claudio Andrea Manzari +1
In recent years, evidence for lepton flavour universality violation beyond the Standard Model has been accumulated. In this context, a singly charged singlet scalar ($ϕ^\…
Global Electroweak Fit and Vector-Like Leptons in Light of the Cabibbo Angle Anomaly
Andreas Crivellin, Fiona Kirk, Claudio Andrea Manzari +1
The "Cabibbo Angle Anomaly" (CAA) originates from the disagreement between the CKM elements and extracted from superallowed beta and kaon decays, respectively, on…
models with less-minimal flavour violation
Lorenzo Calibbi, Andreas Crivellin, Fiona Kirk +2
We study the phenomenology of simplified models with a global flavour symmetry in the quark sector, broken solely by the Standard Model Yukawa couplings. This f…