Related papers: Supernova constraints on lepton flavor violating A…
We propose simple scenarios where lepton flavor-violating couplings generate the observed dark matter abundance through freeze-in of an axion-like particle with mass in the few keV range. Compared to flavor-diagonal freeze-in, this…
We explore the signals of axion-like particles (ALPs) in flavor-changing neutral current (FCNC) processes. The most general effective linear Lagrangian for ALP couplings to the electroweak bosonic sector is considered, and its contribution…
In the two Higgs doublet model type III and in several other extensions of the Standard Model, there are no discrete symmetries that suppress flavor changing couplings at tree level. The experimental observation of the nu_mu -- nu_tau…
We analyze lepton flavor violation (LFV) using the Standard Model Effective Field Theory (SMEFT) framework at the future lepton colliders. Our focus is on the associated production of tau lepton with electron/muon at the electron-positron…
A search for physics beyond the standard model in events with at least three charged leptons (electrons or muons) is presented. The data sample corresponds to an integrated luminosity of 137 fb$^{-1}$ of proton-proton collisions at…
Axion-like particles (ALP) are promising candidates to comprise all the dark matter in the universe. We investigate the ALP couplings to photons and electrons via astrophysical measurements through the search for very-high-energy gamma rays…
Axion-like particles (ALPs) are hypothetical bosons which may couple with photons. Since many ALPs can be emitted from hot and dense astrophysical plasma, nearby supernovae (SNe) are a possible probe into their properties including the ALP…
Lepton flavor violation (LFV) has been discovered in the neutrino sector by neutrino oscillation experiments. The minimally extended Standard Model (SM) to include neutrino masses allows LFV in the charged sector (CLFV) at the loop-level,…
Ultraviolet completions for axion-like particles (ALPs) lighter than the neutral pion generically induce ALP-neutral pion mixing, and are therefore sensitive to direct constraints on the mixing angle. For ALPs below the pion mass, we…
In this Letter we describe a search for lepton flavor violation (LFV) in the bottomonium system. We search for leptonic decays of Upsilon(nS)(n=1,2, and 3) into muon and tau using the data collected with the CLEO III detector. We identify…
Motivated by the recent Xenon1T result, we study a leptophilic flavour-dependent anomaly-free axion-like particle (ALP) and its effects on charged-lepton flavour violation (CLFV). We present two representative models. The first one…
Soft unclustered energy patterns (SUEPs) refer to high-multiplicity, isotropic distributions of low-momentum particles that could arise in strongly-coupled hidden sector theories. A search for SUEPs whose decay products contain muons in the…
We study a new supersymmetric mechanism for lepton flavour violation in muon and tau decays and muon -> e conversion in nuclei, within a minimal extension of the MSSM with low-mass heavy singlet neutrinos and sneutrinos. We find that the…
We revisit the limit on very light axion-like particles (ALPs) from the absence of gamma rays coincidental with the neutrino burst from SN1987A. We use updated supernova simulations, modern models for the magnetic field inside the Galaxy,…
A muon collider would be a powerful probe of flavor violation in new physics. There is a strong complementary case for collider measurements and precision low-energy probes of lepton flavor violation (as well as CP violation). We illustrate…
The formation of a hot and dense core in a core-collapse supernova (SN) can produce massive Beyond Standard Model (BSM) particles. These particles can decay in the stellar envelope, generating positrons either directly or through secondary…
Models involving large extra spatial dimension(s) have interesting predictions on lepton flavor violating processes. We consider some 5D models which are related to neutrino mass generation or address the fermion masses hierarchy problem.…
Axion-like particles (ALPs) may undergo mixing with photons in the presence of astrophysical magnetic fields, leading to alterations in the observed high energy $\gamma$-ray spectra. In this study, we investigate the ALP-photon oscillation…
We reexamine the constraints on mixing between electron and muon or tau neutrinos from shock-reheating and r-process nucleosynthesis in supernovae. To this end neutrino flavor evolution is described by nonlinear equations following from a…
The fundamental description of nature, beyond the Standard Model (SM), may include heavy neutrinos that mix and thus allow processes in which lepton flavor is not preserved. We investigate the impact of charged currents that couple heavy…