Isomery of SU3 states in the strictly restricted dynamics model

Employing the general principles of classification of SU3 states, we have found 285 quantum number isomers (QNI), i.e. nuclei for which there are two possible SU3 quantum number sets, characterized by the maximal eigenvalue of the SU3 group Casimir operator, at the minimal value N-0(min) for the quantum number N-0 of the group U3(A-1) symmetric representation, allowed by the Pauli principle. 41 of these QNI can be attributed to the nun-excited, ground SU3 configurations of realistic nuclei. Two examples of QNI: Si-28 and Zn-60, have been studied in detail in the framework of the strictly restricted dynamics model (SRDM).

Search for a heavy resonance decaying into a Z plus jet final state in p(p)over-bar collisions at root s=1.96 TeV using the D0 detector

We have searched for a heavy resonance decaying into a Z+jet final state in p (p) over bar collisions at a center of mass energy of 1.96 TeV at the Fermilab Tevatron collider using the D0 detector. No indication for such a resonance was found in a data sample corresponding to an integrated luminosity of 370 pb(-1). We set upper limits on the cross section times branching fraction for heavy resonance production at the 95% C.L. as a function of the resonance mass and width. The limits are interpreted within the framework of a specific model of excited quark production.

Dynamics of Bose-Einstein condensates in cigar-shaped traps

The Gross-Pitaevskii equation for a Bose-Einstein condensate confined in an elongated cigar-shaped trap is reduced to an effective system of nonlinear equations depending on only one space coordinate along the trap axis. The radial distribution of the condensate density and its radial velocity are approximated by Gaussian functions with real and imaginary exponents, respectively, with parameters depending on the axial coordinate and time. The effective one-dimensional system is applied to a description of the ground state of the condensate, to dark and bright solitons, to the sound and radial compression waves propagating in a dense condensate, and to weakly nonlinear waves in repulsive condensate. In the low-density limit our results reproduce the known formulas. In the high-density case our description of solitons goes beyond the standard approach based on the nonlinear Schrodinger equation. The dispersion relations for the sound and radial compression waves are obtained in a wide region of values of the condensate density. The Korteweg-de Vries equation for weakly nonlinear waves is derived and the existence of bright solitons on a constant background is predicted for a dense enough condensate with a repulsive interaction between the atoms.

Relativistic dynamics of Qqq systems

The bound state of constituent quarks forming a Qqq composite baryon is investigated in a QCD-inspired effective light-front model. The light-front Faddeev equations are derived and solved numerically. The masses of the spin 1/2 low-lying states of the nucleon, Lambda(0), Lambda(c)(+) and Lambda(b)(0), are found and compared to the experimental data. The data are qualitatively described with a flavor independent effective interaction.

Short-time dynamics of percolation observables

We consider the critical short-time evolution of magnetic and droplet-percolation order parameters for the Ising model in two and three dimensions, through Monte Carlo simulations with the (local) heat-bath method. We find qualitatively different dynamic behaviors for the two types of order parameters. More precisely, we find that the percolation order parameter does not have a power-law behavior as encountered for the magnetization, but develops a scale (related to the relaxation time to equilibrium) in the Monte Carlo time. We argue that this difference is due to the difficulty in forming large clusters at the early stages of the evolution. Our results show that, although the descriptions in terms of magnetic and percolation order parameters may be equivalent in the equilibrium regime, greater care must be taken to interpret percolation observables at short times. In particular, this concerns the attempts to describe the dynamics of the deconfinement phase transition in QCD using cluster observables.

Dynamics of Bose-Einstein condensates with atomic pumping and dissipative processes

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

PRODUCTION of THERMAL PHOTONS IN VISCOUS FLUID DYNAMICS WITH TEMPERATURE-DEPENDENT SHEAR VISCOSITY

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

A search for excited leptons in pp collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Neutron-C-19 scattering near an Efimov state

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

Soliton dynamics at an interface between a uniform medium and a nonlinear optical lattice

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

Observation and properties of the orbitally excited B-s2* meson

We report the direct observation of the excited L=1 state B-s2* in fully reconstructed decays to B+K-. The mass of the B-s2* meson is measured to be 5839.6 +/- 1.1(stat)+/- 0.7(syst) MeV/c(2), and its production rate relative to the B+ meson is measured to be [1.15 +/- 0.23(stat)+/- 0.13(syst)]%.

Kinetic energy sum spectra in nonmesonic weak decay of hypernuclei

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Indications of Suppression of Excited Upsilon States in Pb-Pb Collisions at root(NN)-N-s=2.76 TeV

A comparison of the relative yields of Upsilon resonances in the mu(+)mu(-) decay channel in Pb-Pb and pp collisions at a center-of-mass energy per nucleon pair of 2.76 TeV is performed with data collected with the CMS detector at the LHC. Using muons of transverse momentum above 4 GeV/c and pseudorapidity below 2.4, the double ratio of the Upsilon(2S) and Upsilon(3S) excited states to the Upsilon(1S) ground state in Pb-Pb and pp collisions, [Upsilon(2S + 3S)/Upsilon(1S)](Pb-Pb) /[Upsilon 2S + 3S)/Upsilon(1S)](pp), is found to be 0.31(-0.15)(+0.19) (stat_ +/- 0.03(syst). The probability to obtain the measured value, or lower, if the true double ratio is unity, is calculated to be less than 1%.

Optimal pest control problem in population dynamics

One of the main goals of the pest control is to maintain the density of the pest population in the equilibrium level below economic damages. For reaching this goal, the optimal pest control problem was divided in two parts. In the first part, the two optimal control functions were considered. These functions move the ecosystem pest-natural enemy at an equilibrium state below the economic injury level. In the second part, the one optimal control function stabilizes the ecosystem in this level, minimizing the functional that characterizes quadratic deviations of this level. The first problem was resolved through the application of the Maximum Principle of Pontryagin. The Dynamic Programming was used for the resolution of the second optimal pest control problem.

Comments on nonlinear dynamics of a non-ideal Duffing-Rayleigh oscillator: Numerical and analytical approaches

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