Influence of pions on the hadron-quark phase transition

In this work we present the features of the hadron-quark phase transition diagrams in which the pions are included in the system. To construct such diagrams we use two different models in the description of the hadronic and quark sectors. At the quark level, we consider two distinct parametrizations of the Polyakov-Nambu-Jona-Lasinio (PNJL) models. In the hadronic side, we use a well known relativistic mean-field (RMF) nonlinear Walecka model. We show that the effect of the pions on the hadron-quark phase diagrams is to move the critical end point (CEP) of the transitions lines. Such an effect also depends on the value of the critical temperature (T_0) in the pure gauge sector used to parametrize the PNJL models. Here we treat the phase transitions using two values for T_0, namely, T_0 = 270 MeV and T_0 = 190 MeV. The last value is used to reproduce lattice QCD data for the transition temperature at zero chemical potential.Comment: 3 pages. Proceedings of XXXV Reuni\~ao de Trabalhos sobre F\'isica Nuclear no Brasil 201

Point-Coupling Models from Mesonic Hypermassive Limit and Mean-Field Approaches

In this work we show how nonlinear point-coupling models, described by a Lagrangian density that presents only terms up to fourth order in the fermion condensate $(\bar{\psi}\psi)$, are derived from a modified meson-exchange nonlinear Walecka model. The derivation can be done through two distinct methods, namely, the hypermassive meson limit within a functional integral approach, and the mean-field approximation in which equations of state at zero temperature of the nonlinear point-coupling models are directly obtained.Comment: 18 pages. Accepted for publication in Braz. J. Phy

Cobertura da sala do relicário do mosteiro de Santa Cruz : da inspecção e diagnóstico ao projecto

A existência e difusão de diversas tipologias estruturais encontradas não só em todo o país, mas um pouco por toda a Europa, faz com que a sua conservação, inspecção e utilização sejam de vital importância para a manutenção do património enquanto símbolo de identidade e orgulho nacional. No presente artigo são apresentadas as conclusões obtidas no diagnóstico e inspecção da estrutura existente, com recurso a técnicas não destrutivas (nomeadamente o Pilodyn e o Resistógrafo), referindo-se o seu potencial campo de aplicação, vantagens e limitações, fundamentadas na experiência da sua utilização noutros casos reais. Finalmente, é apresentada a solução proposta para a realização de uma nova cobertura. Precedida e fundamentada no diagnóstico e inspecção realizados, a apresentação da metodologia a adoptar no projecto da nova cobertura tem como objectivo primeiro a manutenção da traça original da antiga cobertura (cota da cumeeira e geometria da antiga cobertura) respeitando diversos condicionalismos estruturais e técnicos existentes

Innovative structural systems for industrial buildings using fiber reinforced concrete and material nonlinear FEM-Based models

Fibre Reinforced Concrete (FRC) can be very effective in precast pre-stressed high strength concrete structures, since shear reinforcement and passive longitudinal bars can be totally replaced by fibre reinforcement. To simulate adequately the fibre reinforcement benefits, material constitutive models, able of capturing the crack initiation and crack propagation need to be used, under the frame-work of FEM-based analysis. In the present work, the use of FRC was explored for the development of innovative structural systems for industrial buildings. The connections between structural precast elements were also simulated. The numerical simulations are described and the results are analyzed and discussed

Canonical Analysis of the Jackiw-Teitelboim Model in the Temporal Gauge. I. The Classical Theory

As a preparation for its quantization in the loop formalism, the 2-dimensional gravitation model of Jackiw and Teitelboim is analysed in the classical canonical formalism. The dynamics is of pure constraints as it is well-known. A partial gauge fixing of the temporal type being performed, the resulting second class constraints are sorted out and the corresponding Dirac bracket algebra is worked out. Dirac observables of this classical theory are then calculated.Comment: 15 pages, Latex. Misprint correction