Related papers: Isosinglet vectorlike leptons at $e^+e^-$ collider…
We search for rare decays of $D$ mesons to hadrons accompany with an electron-positron pair (h(h')$e^+e^-$), using an $e^+e^-$ collision sample corresponding to an integrated luminosity of 2.93 fb$^{-1}$ collected with the BESIII detector…
This letter presents the results of a search for a heavy particle decaying into an e mu, e tau, or mu tau final state in pp collisions at sqrt(s) = 7 TeV. The data were recorded with the ATLAS detector at the LHC during 2011 and correspond…
Recent measurements in $B \to K^{(*)} \mu^+ \mu^-$ decays are somewhat discrepant with Standard Model predictions. They may be harbingers of new physics at an energy scale potentially accessible to direct discovery. We estimate the…
We estimate the smallest branching ratio for the Higgs decay channel $h \rightarrow \mu \tau$, which can be probed at an $e^+e^-$ collider and compare it with the projected reach at the high-luminosity run of the LHC. Using a…
A search for heavy leptons decaying to a $Z$ boson and an electron or a muon is presented. The search is based on $pp$ collision data taken at $\sqrt{s}=8$ TeV by the ATLAS experiment at the CERN Large Hadron Collider, corresponding to an…
A search for charged excited leptons decaying into a lepton and photon has been performed using approximately 680 pb-1 of e+e- collision data collected by the OPAL detector at LEP at centre-of-mass energies between 183 GeV and 209 GeV. No…
The anomalous magnetic moment of the tau lepton $a_\tau = (g_\tau -2)/2$ strikingly evades measurement, but is highly sensitive to new physics such as compositeness or supersymmetry. We propose using ultraperipheral heavy ion collisions at…
The angular analysis of exclusive rare B-meson decays via intermediate vector mesons V into 4-body final states of two pseudo-scalars P_1, P_2 and a pair of light leptons l = e, mu offers a large set of observables. They can be used to test…
We analyze the potential of the CERN Large Hadron Collider (LHC) to search for excited spin-1/2 electrons and neutrinos. Assuming a SU(2)_L X U(1)_Y invariant model, we study in detail the single production of excited electrons and…
By exploiting the relatively long lifetime of the tau lepton, we propose several novel methods for searching for new physics at an electron-positron collider. We consider processes that involve final states consisting of a tau lepton pair…
A model of spin-3/2 vector-like leptons is introduced, which serve as an alternative probe of possible lepton compositeness. Possible signatures at the Large Hadron Collider are explored, and current data are used to constrain the masses of…
We investigate an extension of the left-right symmetric model featuring an additional non-abelian $SU(2)$ gauge symmetry. The particle content is augmented by one generation of vector-like leptons transforming under the fundamental…
At the LHC, a TeV-scale leptoquark (LQ) that decays dominantly to a top quark ($t$) and a light charged lepton ($\ell=e,\mu$) would form a resonance system of \emph{boosted-$t$ $+$ high-$p_{\rm T}$-$\ell$}. We consider all possible vector…
We explore the potential of future high-energy lepton colliders to probe heavy vector resonances. At wakefield colliders, intense beam-beam interactions produce radiation, called beamstrahlung, which redistributes luminosity from the…
It has been recently proposed that neutrino mass could originate from Yukawa interactions of leptons with new colored particles. This raises the interesting possibility of testing mass generation through copious production of those…
The weak bosons, leptons and quarks are considered as composite particles. The interaction of the constituents is a confining gauge interaction. The standard electroweak model is a low energy approximation. The mixing of the neutral weak…
We describe how to probe new physics through examination of the form factors describing the Ztt couplings via the scattering process e^-e^+->t+tbar. We focus on experimental methods on how the top quark momentum can be determined and show…
We discuss the production of heavy leptons at a future high--energy $e^+e^-$ linear collider with a center of mass energy of 500 GeV. Signals and backgrounds are analyzed for their single production in association with ordinary leptons.…
We consider measurements of exclusive rare semi-tauonic $b$-hadron decays, mediated by the $b \rightarrow s \tau^+ \tau^-$ transition, at a future high energy circular electron-positron collider (FCC-$ee$). We argue that the high boosts of…
We consider machine learning techniques associated with the application of a Boosted Decision Tree (BDT) to searches at the Large Hadron Collider (LHC) for pair-produced lepton partners which decay to leptons and invisible particles. This…