We design a search strategy for the Standard Model $t\bar t \bar t$ production at LHC in same-sign dilepton and trilepton channels. study different signal features and, given small expected number of events, we scrutinize detail all reducible irreducible backgrounds. Our analysis shows that by imposing set basic jet lepton selection criteria, SM $pp \to t\bar process could be evidenced near future, within Run-II, when combining both multi-lepton argue this should also used as guideline to...

We study the implications of minimal flavor violating low energy supersymmetry scenarios for search new physics in $B$ and Higgs sectors at Tevatron collider LHC. show that already stringent bound on decay rate ${B}_{s}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ sets strong constraints possibility generating large corrections to mass difference $\ensuremath{\Delta}{M}_{s}$ ${B}_{s}$ eigenstates. also together with constraint branching ratio rare...

In this work we present a new computation of the lepton flavor violating Higgs boson decays that are generated radiatively to one-loop from heavy right-handed neutrinos. We within context inverse seesaw model with three $\nu_R$ and extra singlets $X$, but results could be generalized other low scale models. The novelty our is it uses completely different method by means mass insertion approximation which works electroweak interaction states instead usual 9 physical neutrino eigenstates...

We present a collection of CP-odd observables for the process $$ pp\to t\left(\to b{\ell}^{+}{\nu}_{\ell}\right)\overline{t}\left(\to \overline{b}{\ell}^{-}{\overline{\nu}}_{\ell}\right) H that are linearly dependent on scalar (k t ) and pseudoscalar \left({\tilde{k}}_t\right) top-Higgs coupling hence sensitive to corresponding relative sign. The proposed based triple product (TP) correlations we extract from expression differential cross section in terms spin vectors top antitop quarks. In...

We study the impact of machine-learning algorithms on LHC searches for leptoquarks in final states with hadronically decaying tau leptons, multiple <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>b</a:mi></a:math>-jets, and large missing transverse momentum. Pair production scalar decays only into third-generation leptons quarks is assumed. Thanks to use supervised learning tools unbinned methods handle high-dimensional states, we consider simple selection cuts...

Gauge anomalous quantum field theories are inconsistent as full UV since they lead to the breaking of Lorentz invariance or Unitarity, well non-renormalizability. It is known, however, that can be interpreted effective (EFT) with a cut-off. The latter cannot made arbitrarily large and it related energy scale at which additional fermions suitable gauge charges enter, rendering model anomaly-free. A nondecoupling effect remains in EFT appearance loop-induced triple-gauge couplings,...

In this paper we study the lepton favor violating decay channels of neutral Higgs bosons Minimal Supersymmetric Standard Model into a and an anti-lepton different flavor. We work in context most general flavor mixing scenario slepton sector, contrast to minimal violation assumption more frequently used. Our analytic computation is one-loop diagrammatic one, but full which usually referred physical mass basis, use here instead Mass Insertion Approximation (MIA) uses electroweak interaction...

$B\ensuremath{\rightarrow}\ensuremath{\phi}{K}^{*}$ ($\overline{b}\ensuremath{\rightarrow}\overline{s}$) is three separate decays, one for each polarization of the final-state vector mesons (one longitudinal, two transverse). It observed that fraction transverse ${f}_{T}$, and longitudinal ${f}_{L}$, are roughly equal: ${f}_{T}/{f}_{L}\ensuremath{\simeq}1$, in opposition to naive expectation ${f}_{T}\ensuremath{\ll}{f}_{L}$. If requires a single explanation all puzzles, possibilities remain...

In this paper, we examine $B\ensuremath{\rightarrow}VT$ decays ($V$ is a vector and $T$ tensor meson), whose final-state particles can have transverse or longitudinal polarization. Measurements been made of $B\ensuremath{\rightarrow}\ensuremath{\phi}{K}_{2}^{*}$, it found that ${f}_{T}/{f}_{L}$ small, where ${f}_{T}$ (${f}_{L}$) the fraction (longitudinal) decays. We find standard model naively predicts ${f}_{T}/{f}_{L}\ensuremath{\ll}1$. The two extensions naive which proposed to explain...

In this paper we study the effective lepton flavor violating vertex of an electroweak Z gauge boson and two charged leptons with different flavor, $$l_k$$ $$l_m$$ , that is generated to one-loop in low scale seesaw models right handed neutrinos whose masses are heavier than scale. We first compute form factor describing by using mass insertion approximation, where non-diagonal entries neutrino Yukawa coupling matrix unique origin, level, changing processes external legs. Then, considering...

We consider possible effects of New Physics (NP) on the angular distributions decay B^0 --> \phi K^{*0}, showing how these depend nature nonstandard interactions. In a general framework based factorization, we show that triple products can be used to probe chirality NP currents. this analysis take into account presence non-vanishing strong phases, which is motivated by recent experimental evidence. It seen observability right-handed strongly dependent relation between relative magnitude...

Senjanovi\ifmmode \acute{c}\else \'{c}\fi{} and Tello have analyzed how one could determine the neutrino Dirac mass matrix in minimal left-right model, assuming that matrices for light heavy neutrinos be taken as inputs. They provided an analytical solution case symmetry is implemented via a generalized parity this remains unbroken Dirac-Yukawa sector. We extend work of to which broken In case, elegant method outlined by breaks down we need adopt numerical approach. Several iterative...

In this letter we reinterpret and reanalyze the available data of B-meson factories showing existence direct experimental evidence time reversal invariance violation in B-mesons. This reinterpretation consists using observables to define a new observable which, model-independent way without assuming CPT invariance, compares transition between B 0 here-defined α -state, with its reversed transition. The then offers probe it is therefore independent any conclusion obtained from current...

Abstract Machine-learning techniques have become fundamental in high-energy physics and, for new searches, it is crucial to know their performance terms of experimental sensitivity, understood as the statistical significance signal-plus-background hypothesis over background-only one. We present here a simple method that combines power current machine-learning face high-dimensional data with likelihood-based inference tests used traditional analyses, which allows us estimate sensitivity both...

We study the production of scalar leptoquarks at IceCube, in particular, a particle transforming as triplet under weak interaction. The existence electroweak-triplet scalars is highly motivated by models grand unification and also within radiative seesaw for neutrino mass generation. In our framework, we extend Standard Model single colored leptoquark analyze its implications on excess ultra-high energy events observed IceCube collaboration. consider only couplings between to first...

We study several simplified dark matter (DM) models and their signatures at the LHC using neural networks. focus on usual monojet plus missing transverse energy channel, but to train algorithms we organize data in 2D histograms instead of event-by-event arrays. This results a large performance boost distinguish between standard model (SM) only SM new physics signals. use kinematic features as input which allow us describe families with single sample. found that network does not depend...

Recognizing hadronically decaying top-quark jets in a sample of jets, or even its total fraction the sample, is an important step many LHC searches for Standard Model and Beyond physics as well. Although there exists outstanding top-tagger algorithms, their construction expected performance rely on Montecarlo simulations, which may induce potential biases. For these reasons we develop two simple unsupervised algorithms based performing Bayesian inference mixture model. In one them use...