Related papers: CPT-violating effects in muon decay
We study breakdown of $CPT$ symmetry which can occur in the decay process $B \bar B \to l^\pm X^\mp f$ with $f$ being a CP eigenstate. In this process, the standard model expectations for time ordered semi-leptonic and hadronic events, i.e.…
Quantitative bounds on Lorentz symmetry violation in the neutrino sector have been obtained by analyzing existing laboratory data on neutron $\beta$ decay and pion leptonic decays. In particular some parameters appearing in the…
An overview of the theoretical framework of the Standard Model Extension (SME) that allows for a parametrization of Lorentz and CPT violating effects using effective field theory will be presented. A review of current bounds on these…
This talk provides a status report on CPT violation in neutral-meson oscillations, focusing on implications of the CPT- and Lorentz-violating standard-model extension.
Present precision measurements of the neutron life time lead to a CKM matrix element $|V_{ud}|$ which is three standard deviations off the value inferred from heavy quark decays etc. We investigate the possibility whether isospin-breaking…
The prospects of studying nonminimal operators for Lorentz violation using spectroscopy experiments with light atoms and muon spin-precession experiments are presented. Possible improvements on bounds on minimal and nonminimal operators for…
A mechanism for spontaneous CPT breaking appears in string theory. Possible implications for present-energy particle models are discussed. A realistic string theory might exhibit CPT violation at levels detectable in current or future…
Upon a suggestion of Kostelecky et al., we have performed a test of CPT and Lorentz invariance from the microwave spectroscopy of muonium. New terms in their standard model extension violating CPT and Lorentz symmetry would appear as…
We present a general model-independent and rephase-invariant formalism that cleanly relates CP and CPT noninvariant observables to the fundamental parameters. Different types of CP and CPT violations in the K^0-, B^0-, B_s^0- and…
We calculate the possible CP violating asymmetries for LFV decays mu -> e gamma and tau -> mu gamma. Our predictions depend on the chosen new model independent contribution. The result of measurements of such asymmetries for these decays…
We study the pion decays with intermediate on-shell neutrinos $N$ into two electrons and a muon, $\pi^{\pm} \to e^{\pm} N \to e^{\pm} e^{\pm} \mu^{\mp} \nu$. We investigate the branching ratios ${\rm Br}_{\pm} = [\Gamma(\pi^- \to e^- e^-…
We study the implications of the experimental results on the \mu -> e\gamma decay rate and the muon anomalous magnetic moment, on muonic lepton flavor violating processes, such as \mu -> 3 e and \mu N -> e N. We use a model independent…
The success of the quantum level predictions of the Standard Model on the $Z$ boson properties, on $\mw$ and on $\mt$, which makes use of the muon lifetime as an input, implies a stringent constraint on new physics contributions to the…
In this work we investigate the possibility to observe $C\!P$-violation in $\eta$ decays containing muons at the proposed REDTOP experiment. Employing the SMEFT to parametrize the new-physics $C\!P$-violating effects, we find that a single…
A phenomenological paradigm for the study of CPT-violating effects in the neutral kaon system is presented. Besides the familiar direct and indirect breakings, it encodes possible phenomena leading to irreversibility and dissipation, that…
A theoretical framework is introduced that describes possible CPT-violating effects in the context of quantum electrodynamics. Experiments comparing the anomalous magnetic moments of the electron and the positron can place tight limits on…
We revisit the theory and constraints on axion-like particles (ALPs) interacting with leptons. We clarify some subtleties in the constraints on ALP parameter space and find several new opportunities for ALP detection. We identify a…
We consider the transformation properties of fermions under the discrete symmetries CPT, CP, and C in the presence of B-L violation. We thus generalize the analysis of the known properties of Majorana neutrinos, probed via neutrinoless…
We examine the process of Compton scattering, in the presence of a Lorentz- and CPT-violating modification to the structure of the electron. We calculate the complete tree-level contribution to the cross section; our result is valid to all…
We analyzed the electron neutrino data of the Gallium radioactive source experiments and the electron antineutrino data of the reactor Bugey and Chooz experiments in terms of neutrino oscillations allowing for a CPT-violating difference of…