Search for WW gamma and WZ gamma production and constraints on anomalous quartic gauge couplings in pp collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

VSR symmetries in the DKP algebra: The interplay between Dirac and Elko spinor fields

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On symmetries of singular implicit ODEs

We study implicit ODEs, cubic in derivative, with infinitesimal symmetry at singular points. Cartan showed that even at regular points the existence of nontrivial symmetry imposes restrictions on the ODE. Namely, this algebra has the maximal possible dimension 3 iff the web of solutions is flat. For cubic ODEs with flat 3-web of solutions we establish sufficient conditions for the existence of nontrivial symmetries at singular points and show that under natural assumptions such a symmetry is semi-simple, i.e. is a scaling is some coordinates. We use this symmetry to find first integrals of the ODE.

Local classification of singular hexagonal 3-webs with holomorphic Chern connection form and infinitesimal symmetries

Implicit ODE, cubic in derivative, generically has no infinitesimal symmetries even at regular points with distinct roots. Cartan showed that at regular points, ODEs with hexagonal 3-web of solutions have symmetry algebras of the maximal possible dimension 3. At singular points such a web can lose all its symmetries. In this paper we study hexagonal 3-webs having at least one infinitesimal symmetry at singular points. In particular, we establish sufficient conditions for the existence of non-trivial symmetries and show that under natural assumptions such a symmetry is semi-simple, i.e. is a scaling in some coordinates. Using the obtained results, we provide a complete classification of hexagonal singular 3-web germs in the complex plane, satisfying the following two conditions: 1) the Chern connection form is holomorphic at the singular point, 2) the web admits at least one infinitesimal symmetry at this point. As a by-product, a classification of hexagonal weighted homogeneous 3-webs is obtained.

Measurement of the pp → ZZ production cross section and constraints on anomalous triple gauge couplings in four-lepton final states at √s = 8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Pseudospin and spin symmetries in 1+1 dimensions: the case of the Coulomb potential

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Measurement of the Z gamma production cross section in pp collisions at 8 TeV and search for anomalous triple gauge boson couplings

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Limits on anomalous top-quark gauge couplings from Tevatron and LHC data

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Search for anomalous production of events with three or more leptons in pp collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Quartic anomalous couplings in eγ colliders

We study the production of gauge-boson pairs at the next generation of linear e+e- colliders operating in the eγ mode. The processes eγ → VV′F (V,V′ = W,Z, or γ and F = e or ν) can give valuable information on possible deviations of the quartic vector-boson couplings from the Standard Model predictions. We establish the range of the new couplings that can be explored in these colliders based on a 3σ effect in the total cross section. We also present several kinematical distributions of the final state particles that could manifest the underlying new dynamics. Our results show that an eγ collider can extend considerably the bounds on anomalous interactions coming from oblique radiative corrections and from direct searches in e+e- colliders.

Anomalous couplings of the third generation in rare B decays

We study the potential effects of anomalous couplings of the third generation quarks to gauge bosons in rare B decays. We focus on the constraints from flavor changing neutral current processes such as b→sγ and b →sl+l-. We consider both dimension-four and dimension-five operators and show that the latter can give large deviations from the standard model in the still unobserved dilepton modes, even after the bounds from b→sγ and precision electroweak observables are taken into account. ©2000 The American Physical Society.

Anomalous couplings in e(+)e(-)->W+W- gamma at CERN LEP 2 and NLC

We present sensitivity limits on the coefficients of a dimension-6 effective Lagrangian that parametrizes the possible effects of new physics beyond the standard model. Our results are based on the study of the process e(+)e(-)-->W+W- y at CERN LEP 2 and NLC energies. In our calculations, we include all the new anomalous interactions, involving vectors and Higgs bosons, and take into account the standard model irreducible background. We analyze the impact of these new interactions on the total cross section. including the effects of the initial electron and final W polarizations. We then focus on the operators that will not be constrained by the e(+)e(-)-->W+W- process, obtaining limits based on the photon energy distribution.

Anomalous Higgs boson contribution to e(+)e(-)->b(b)over-bar gamma at CERN LEP 2

We study the effect of anomalous Hγγ and HZγ couplings, described by a general effective Lagrangian, on the process e+e-→bb̄γ at CERN LEP 2 energies. We include the relevant irreducible standard model background to this process, and from the photon energy spectrum, we determine the reach of LEP 2 to unravel the anomalous couplings by analyzing the significance of the signal for a Higgs boson with a mass up to 150 GeV.