相关论文: Can $\mu$--$e$ Conversion in Nuclei be a Good Prob…
Recent studies of novel four-body lepton number violating decays of $\tau$ leptons and neutral $B$ mesons are summarized and updated. These decays are assumed to be enhanced by the exchange of resonant Majorana neutrinos. It is shown that…
We study the prospects to detect at hadron colliders the Lepton Flavour Violating Higgs decay H --> tau mu, which can reach substantial branching fractions in several extensions of the SM. Among them, the generic two higgs doublet model can…
The ratio of the Higgs couplings to $WW$ and $ZZ$ pairs, $\lambda_{WZ}$, is a fundamental parameter in electroweak symmetry breaking as well as a measure of the (approximate) custodial symmetry possessed by the gauge boson mass matrix. We…
The quartic Higgs-gauge-boson coupling $g_{hhWW}$ is sensitive to the electroweak symmetry breaking mechanism, however, it is challenging to be measured at the large hadron collider. We show that the coupling can be well probed at future…
The Higgs-strahlung process $\ell^+\ell^-\to Z h$ is one of the most important production channels of the standard model Higgs boson $h$ at the lepton colliders. The cross section reaches the maximum value slightly above the threshold…
We point out that the results of many baryogenesis scenarios operating at or below the TeV scale are rather sensitive to the rate of anomalous fermion number violation across the electroweak crossover. Assuming the validity of the Standard…
In this paper we compare $H^+H^-$ and $W^+W^-$ into four-fermion production at centre-of-mass energies typical of LEP2 and somewhat larger. The theoretical framework considered is the Minimal Supersymmetric Standard Model. The interest in…
We estimate that the LHC could set bounds BR(Z -> mu^\pm e^\mp) < 4.1 * 10^{-7} and BR(Z -> tau^\pm mu^\mp)< 3.5 * 10^{-6} (at 95% C.L.) with 20 inverse fb of data at 8 TeV. A similar sensitivity can be anticipated for Z -> tau^\pm e^\mp,…
We investigate the possibility of probing the triplet Higgs boson sector via single charged Higgs production in the process $e^+ e^- \to H^+ l \nu_l$, at high energy electron-positron colliders, using the tree level $H^+W^-Z$ coupling which…
In this paper, we study the extent to which CP parity of a Higgs boson, and more generally its anomalous couplings to gauge bosons, can be measured at the LHC and a future electron-positron collider. We consider several processes, including…
We study the general Zee model, which includes an extra Higgs scalar doublet and a new singly-charged scalar singlet. Neutrino masses are generated at one-loop level, and in order to describe leptonic mixing, both the Standard Model and the…
We recalculate the leading one-loop contributions to mu > e gamma and mu -> eee in the Littlest Higgs model with T-parity, recovering previous results for the former. When all the Goldstone interactions are taken into account, the latter is…
We study the perspective to observe lepton number violating signatures from heavy Majorana neutrino decays at colliders in view of the requirement to explain the light neutrino masses via the seesaw mechanism. In the minimal model with only…
We explore the Higgs mass spectrum in a class of Two Higgs Doublet Models (THDMs) in which a scalar SU(2)_L doublet interacts only with quarks, while the second one interacts only with leptons. The spectrum includes two CP-even Higgs…
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…
In this paper we assume the Higgs is an elementary scalar, and study how new physics could affect its couplings to electroweak gauge bosons. Adding LHC data to LEP data provides new, more stringent limits, particularly when the Higgs to two…
In this paper we propose to use convolutional neural networks (CNNs) to improve the precision measurement of the Higgs boson-gluon effective coupling at lepton colliders. The CNN is employed to recognize the Higgs boson and a $Z$ boson…
The NA62 experiment at CERN reports a search for the lepton number violating decays $K^+\to\pi^-e^+e^+$ and $K^+\to\pi^-\mu^+\mu^+$ using a data sample collected in 2017. No signals are observed, and upper limits on the branching fractions…
Lepton flavor violating Higgs decays could appear in scenarios beyond the Standard Model of particle physics. In this article, we study the sensitivity of a future Compact Linear Collider (CLIC) to such processes, namely, $h\rightarrow…
A search for the single production of doubly-charged Higgs bosons H^{\pm \pm} in ep collisions is presented. The signal is searched for via the Higgs decays into a high mass pair of same charge leptons, one of them being an electron. The…