Isospin Constraints on the Parametric Coupling Model for Nuclear Matter

We make use of isospin constraints to study the parametric coupling model and the properties of asymmetric nuclear matter. Besides the usual constraints for nuclear matter - effective nucleon mass and the incompressibility at saturation density - and the neutron star constraints - maximum mass and radius - we have studied the properties related with the symmetry energy. These properties have constrained to a small range the parameters of the model. We have applied our results to study the thermodynamic instabilities in the liquid-gas phase transition as well as the neutron star configurations.Comment: 11 pages, 10 figure

O planetário da Unipampa e a divulgação da ciência na região da campanha sulriograndense

Este trabalho apresenta um estudo sobre a contribuição de um programa de extensão para a divulgação da ciência, desenvolvido na região da campanha sulriograndense e que culminou na construção do Planetário da Unipampa. Trazemos aqui um breve histórico do surgimento, da implantação e do desenvolvimento dos planetários no Brasil e no mundo, sobre o qual pautamos algumas reflexões críticas sobre o desenvolvimento do programa de extensão Astronomia para Todos (desde 2009). Por fim, apresentamos o trabalho executado atualmente no planetário juntamente com as perspectivas futuras para a divulgação da ciência em uma região carente destes espaços. Estas reflexões apontam para a importância da ampliação destes espaços museológicos, voltados para a divulgação da ciência em todo o Brasil

Status report of the Schenberg gravitational wave antenna

Here we present a status report of the Schenberg antenna. In the past three years it has gone to a radical upgrading operation, in which we have been installing a 1K pot dilution refrigerator, cabling and amplifiers for nine transducer circuits, designing a new suspension and vibration isolation system for the microstrip antennas, and developing a full set of new transducers, microstrip antennas, and oscillators. We are also studying an innovative approach, which could transform Schenberg into a broadband gravitational wave detector

The Schenberg spherical gravitational wave detector: the first commissioning runs

Here we present a status report of the first spherical antenna project equipped with a set of parametric transducers for gravitational detection. The Mario Schenberg, as it is called, started its commissioning phase at the Physics Institute of the University of Sao Paulo, in September 2006, under the full support of FAPESP. We have been testing the three preliminary parametric transducer systems in order to prepare the detector for the next cryogenic run, when it will be calibrated. We are also developing sapphire oscillators that will replace the current ones thereby providing better performance. We also plan to install eight transducers in the near future, six of which are of the two-mode type and arranged according to the truncated icosahedron configuration. The other two, which will be placed close to the sphere equator, will be mechanically non-resonant. In doing so, we want to verify that if the Schenberg antenna can become a wideband gravitational wave detector through the use of an ultra-high sensitivity non-resonant transducer constructed using the recent achievements of nanotechnology