Related papers: $\Delta L = 3$ processes: Proton decay and LHC
We construct a simple model of the Double Drell--Yan Process (DDYP) for proton--proton collisions and investigate its possible contribution to the background for the Higgs-boson searches at the LHC. We demonstrate that under the assumption…
We propose the minimal and renormalizable non-supersymmetric top SU(5) models where the $SU(5)\times SU(3)'_C \times SU(2)'_L \times U(1)'_Y$ gauge symmetry is broken down to the Standard Model (SM) gauge symmetry at the TeV scale. The…
A search for baryon number violation (BNV) in top-quark decays is performed using pp collisions produced by the LHC at sqrt(s) = 8 TeV. The top-quark decay considered in this search results in one light lepton (muon or electron), two jets,…
A direct search for charged lepton-flavour violation in top-quark decays is presented. The data analysed correspond to $79.8\ \text{fb}^{-1}$ of proton--proton collisions at a centre-of-mass energy of $\sqrt{s}=13\ \text{TeV}$ recorded by…
We discuss rare kaon decays that violate charged-lepton flavour conservation in supersymmetric theories with and without R parity, in view of possible experiments using an intense proton source as envisaged for a neutrino factory. In the…
We calculate the baryon asymmetry of the Universe resulting from the combination of higher-dimensional Lorentz-noninvariant CPT-odd operators and dimension five operators that induce the majorana mass for neutrinos. The strength of…
In this letter, we use LHC data from the Drell-Yan processes $pp\to\ell_i\ell_j$ (with $i\neq j$) to derive model-independent upper limits on lepton-flavor-violating meson decays. Our analysis is based on an Effective Field Theory (EFT)…
A search for the lepton-flavour violating decay $D^0 \to e^\pm \mu^\mp$ is made with a dataset corresponding to an integrated luminosity of 3.0 fb$^{-1}$ of proton-proton collisions at centre-of-mass energies of $7$ TeV and $8$ TeV,…
It is shown that the R-parity violating decays of the lighter top squarks (${\widetilde t}_1$) triggered by the lepton number violating couplings $\lambda^{\prime}_{i33}$, where the lepton family index i = 1-3, can be observed at the LHC…
We discuss the relation between lepton number violation at high and low energies, particularly, the constraints on baryogenesis models, which would be implied by an observation of neutrinoless double beta decay. The primordial baryon…
If Lorentz and CPT violation exist, they could affect the decays of scalar and pseudoscalar particles. For a decay into a fermion and an antifermion (not necessarily of the same mass), both the total decay rate and the outgoing particle…
Results are reported from a search for the lepton flavor violating decay $\tau$ $\to$ 3$\mu$ in proton-proton collisions at $\sqrt{s} =$ 13 TeV. The data sample corresponds to an integrated luminosity of 33.2 fb$^{-1}$ recorded by the CMS…
We calculate the lifetime of the deuteron with dimension-nine quark operators that violate baryon number by two units. We construct an effective field theory for $|\Delta B|=2$ interactions that give rise to neutron-antineutron…
Working within the Standard Model effective field theory approach, we examine the possibility to test charged lepton flavour violating (cLFV) new physics (NP) by angular measurements of the outgoing electron and positrons in the polarised…
The non-observation of baryon number violation suggests that the scale of baryon-number violating interactions at zero temperature is comparable to the GUT scale. However, the pertinent measurements involve hadrons made of the…
Starting from a general effective Lagrangian for lepton flavor violation (LFV) in quark-lepton transitions, we derive constraints on the effective coefficients from the high-mass tails of the dilepton processes $pp \to \ell_k \ell_l$ (with…
Some models of leptogenesis involve a nearly-degenerate pair of heavy Majorana neutrinos $N_{1,2}$ whose masses can be small, $O({\rm GeV})$. There can be heavy-light neutrino mixing parametrized by $|B_{\ell N}|^2 = 10^{-5}$, which leads…
Experiments involving proton-proton collisions at energies $\sqrt{s_{NN}}$ = 0.9, 2.76 and 7 TeV in Large Hadron Collider (LHC) have produced a vast amount of high-precision data. Here, in this work, we have chosen to analyse the two…
We investigate the simplest gauge theory for spontaneous R-parity breaking and its testability at the LHC. This theory based on a local B-L gauge symmetry can be considered as the simplest framework for understanding the origin of the…
A first search for the lepton-flavour violating decays $B^0 \to K^{*0} \tau^\pm \mu^\mp$ is presented. The analysis is performed using a sample of proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of…