946 citations · 7.4k across the 79 of their papers we have counts for
75 papers · 1 filter
What is Leading Order for LFV in SMEFT?
Marco Ardu, Sacha Davidson
Upcoming searches for lepton flavour change (LFV) aim to probe New Physics(NP) scales up to TeV, implying that they will be sensitive to NP at lower scales that is sup…
Probing contact interactions with conversion
Sacha Davidson, Yoshitaka Kuno, Yuichi Uesaka +1
Contact interactions of a muon, an electron and two photons can contribute to the decay , but also to the conversion of a muon into an electron in the electric field of…
Charged lepton flavour change and Non-Standard neutrino Interactions
Sacha Davidson, Martin Gorbahn
Non-Standard neutrino Interactions (NSI) are vector contact interactions involving two neutrinos and two first generation fermions, which can affect neutrino propagation in matter.…
Selecting mu -> e Conversion Targets to distinguish Lepton Flavour-Changing Operators
Sacha Davidson, Yoshitaka Kuno, Masato Yamanaka
The experimental sensitivity to conversion on nuclei is set to improve by four orders of magnitude in coming years. However, various operator coefficients add coherently i…
Axion absorption and the spin temperature of primordial hydrogen
Adrien Auriol, Sacha Davidson, Georg Raffelt
An absorption dip in the spectrum of the cosmic microwave background observed by the EDGES experiment suggests an unexplained reduction of the hydrogen spin temperature at cosmic r…
Majorana Neutrino Masses in the RGEs for Lepton Flavour Violation
Sacha Davidson, Martin Gorbahn, Matthew Leak
We suppose that the observed neutrino masses can be parametrised by a lepton number violating dimension-five operator, and calculate the mixing of double insertions of this operato…
Constraints on 2l2q operators from flavour-changing meson decays
Sacha Davidson, Albert Saporta
We study lepton flavour violating two- and three-body decays of pseudoscalar mesons in Effective Field Theory (EFT). We give analytic formulae for the decay rates in the presence o…
Spin-dependent Conversion on Light Nuclei
Sacha Davidson, Yoshitaka Kuno, Albert Saporta
The experimental sensitivity to conversion will improve by four or more orders of magnitude in coming years, making it interesting to consider the "spin-dependent" (SD) co…
Spin-dependent conversion
Vincenzo Cirigliano, Sacha Davidson, Yoshitaka Kuno
The experimental sensitivity to conversion on nuclei is expected to improve by four orders of magnitude in coming years. We consider the impact of flavour-changin…
Renormalisation-group improved analysis of processes in a systematic effective-field-theory approach
Andreas Crivellin, Sacha Davidson, Giovanni Marco Pruna +1
In this article, a complete analysis of the three muonic lepton-flavour violating processes , and coherent nuclear conversion is performed in the frame…
Complementarity in lepton-flavour violating muon decay experiments
A. Crivellin, S. Davidson, G. M. Pruna +1
This note presents an analysis of lepton-flavour-violating muon decays within the framework of a low-energy effective field theory that contains higher-dimensional operators allowe…
Mu to e gamma and matching at mW
Sacha Davidson
Several experiments search for μ- e flavour change, for instance in μ->e conversion, μ-> e γ, and μ-> 3e. This paper studies how to translate these experimental constraints from lo…
Mu to e gamma in the 2 Higgs Doublet Model: an exercise in EFT
Sacha Davidson
The 2 Higgs Doublet Model (2HDM) of type III has renormalisable Lepton Flavour-Violating couplings, and its one and two-loop ("Barr-Zee") contributions to are known. In…
Lepton Flavour Violating top decays at the LHC
Sacha Davidson, Michelangelo L. Mangano, Stephane Perries +1
We consider lepton flavour violating decays of the top quark, mediated by four-fermion operators. We compile constraints on a complete set of SU(3)*U(1)-invariant operators, arisin…
A facility to Search for Hidden Particles at the CERN SPS: the SHiP physics case
Sergey Alekhin, Wolfgang Altmannshofer, Takehiko Asaka +82
This paper describes the physics case for a new fixed target facility at CERN SPS. The SHiP (Search for Hidden Particles) experiment is intended to hunt for new physics in the larg…
The Pressure of Misalignment Axions: a Difference from WIMPs in Galaxy Formation?
Sacha Davidson
Two populations of axions can contribute to cold dark matter: the classical field produced via the misalignment mechanism, and the modes produced in the decay of strings. The class…
Of Contact Interactions and Colliders
Sacha Davidson, Sebastien Descotes-Genon, Patrice Verdier
The hierarchy of scales which would allow dimension-six contact interactions to parametrise New Physics may not be verified at colliders. Instead, we explore the feasability and us…
Estimated constraints on t-channel Leptoquark exchange from LHC contact interaction searches
Assia Bessaa, Sacha Davidson
The t-channel exchange of a first generation leptoquark could contribute to the cross-section for q q-bar to e+e-. The leptoquark is off-shell, so this process can be sensitive to…
Axions: Bose Einstein Condensate or Classical Field?
Sacha Davidson
The axion is a motivated dark matter candidate, so it would be interesting to find features in Large Scale Structures specific to axion dark matter. Such features were proposed for…
Including the Z in an Effective Field Theory for dark matter at the LHC
Sacha Davidson
An Effective Field Theory for dark matter at a TeV-scale hadron collider should include contact interactions of dark matter with the partons, the Higgs and the Z. This note estimat…
Constraining flavoured contact interactions at the LHC
Sacha Davidson, Sébastien Descotes-Genon
Contact interactions are the low-energy footprints of New Physics, so ideally, constraints upon them should be as generic and model independent as possible. Hadron colliders search…
Baryogenesis through split Higgsogenesis
Sacha Davidson, Ricardo Gonzalez Felipe, H. Serodio +1
We study the cosmological evolution of asymmetries in the two-Higgs doublet extension of the Standard Model, prior to the electroweak phase transition. If Higgs flavour-exchanging…
Bose Einstein condensation of the classical axion field in cosmology?
Sacha Davidson, Martin Elmer
The axion is a motivated cold dark matter candidate, which it would be interesting to distinguish from weakly interacting massive particles. Sikivie has suggested that axions could…
LHC sensitivity to the decay of a Higgs boson to tau mu
Sacha Davidson, Patrice Verdier
We study the sensitivity of the LHC, with 20 inverse-fb of data, to lepton flavour violating Higgs boson decays h -> tau+ mu- (and h -> tau+ e-). We consider the large population o…