Search for pair produced fourth-generation up-type quarks in pp collisions at root s=7 TeV with a lepton in the final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for pair production of doubly charged Higgs bosons in the H(++)H(--)->mu(+)mu(+)mu(-)mu(-) final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for first generation leptoquark pair production in the electron plus missing energy plus jets final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for New Physics in the Multijet and Missing Transverse Momentum Final State in Proton-Proton Collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for large extra dimensions in the diphoton final state at the Large Hadron Collider

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for anomalous t(t)over-bar production in the highly-boosted all-hadronic final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Final state and thermodynamics of a dark energy universe

As it follows from the classical analysis, the typical final state of a dark energy universe where a dominant energy condition is violated is a finite-time, sudden future singularity (a big rip). For a number of dark energy universes (including scalar phantom and effective phantom theories as well as specific quintessence models) we demonstrate that quantum effects play the dominant role near a big rip, driving the universe out of a future singularity (or, at least, moderating it). As a consequence, the entropy bounds with quantum corrections become well defined near a big rip. Similarly, black hole mass loss due to phantom accretion is not so dramatic as was expected: masses do not vanish to zero due to the transient character of the phantom evolution stage. Some examples of cosmological evolution for a negative, time-dependent equation of state are also considered with the same conclusions. The application of negative entropy (or negative temperature) occurrence in the phantom thermodynamics is briefly discussed.

Search for a narrow, spin-2 resonance decaying to a pair of Z bosons in the qq̄ℓ+ℓ- final state

Results are presented from a search for a narrow, spin-2 resonance decaying into a pair of Z bosons, with one Z-boson decaying into leptons (e+e- or μ+μ-) and the other into jets. An example of such a resonance is the Kaluza-Klein graviton, GKK, predicted in Randall-Sundrum models. The analysis is based on a 4.9 fb-1 sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected with the CMS detector at the LHC. Kinematic and topological properties including decay angular distributions are used to discriminate between signal and background. No evidence for a resonance is observed, and upper limits on the production cross sections times branching fractions are set. In two models that predict Z-boson spin correlations in graviton decays, graviton masses are excluded lower than a value which varies between 610 and 945 GeV, depending on the model and the strength of the graviton couplings. © 2012 CERN.

Measurement of the t̄t production cross section in the all-jet final state in pp collisions at √s=7 TeV

A measurement is presented of the t̄t production cross section σt̄t in proton-proton collisions at a centre-of-mass energy of 7 TeV, in the all-jet final state that contains at least six jets, two of which are tagged as originating from b quarks. The data correspond to an integrated luminosity of 3.54 fb-1, collected with the CMS detector at the LHC. The cross section is determined through an unbinned maximum likelihood fit of background and t̄t signal to the reconstructed mass spectrum of t̄t candidates in the data, in which events are subjected to a kinematic fit assuming a t̄t → W+bW-̄b → 6 jets hypothesis. The measurement yields σt̄t = 139±10(stat.)±26(syst.)±3(lum.)pb, a result consistent with those obtained in other t̄t decay channels, as well as with predictions of the standard model. © 2013 CERN for the benefit of the CMS collaboration.

Search for top-squark pair production in the single-lepton final state in pp collisions at

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for Top-Quark Partners with Charge 5/3 in the Same-Sign Dilepton Final State

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the properties of a Higgs boson in the four-lepton final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for new physics in the multijet and missing transverse momentum final state in proton-proton collisions at root s=8 Tev

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for W ' -> tb decays in the lepton plus jets final state in pp collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for pair production of excited top quarks in the lepton plus jets final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)