BEC-BCS crossover in a cold and magnetized two color NJL model

The BEC-BCS crossover for a NJL model with diquark interactions is studied in the presence of an external magnetic field. Particular attention is paid to different regularization schemes used in the literature. A thorough comparison of results is performed for the case of a cold and magnetized two-color NJL model. According to our results, the critical chemical potential for the BEC transition exhibits a clear inverse magnetic catalysis effect for magnetic fields in the range $1 \lesssim eB/m_\pi^2 \lesssim 20$. As for the BEC-BCS crossover, the corresponding critical chemical potential is very weakly sensitive to magnetic fields up to $eB \sim 9\ m_\pi^2$, showing a much smaller inverse magnetic catalysis as compared to the BEC transition, and displays a strong magnetic catalysis from this point on.Comment: 15 pages, 8 figures; v2 PRD versio

Insetos e ácaros pragas associados a cultura da mandioca no Brasil e meios de controle.

Inúmeros são os fatores que influenciam na produção da mandioca e, entre eles, as pragas podem acarretar grandes reduções. A planta e atacada por um grande número de artropodos, alguns dos quais causam danos econômicos consideráveis. Em função das características sócio-econômicas da cultura e seu período vegetativo longo, a aplicação continua de inseticidas para controlar as pragas torna-se bastante onerosa, razão pela qual o controle químico e uma pratica que raramente se justifica economicamente. E importante conhecer tanto as pragas principais como as de menor importância, o que varia de região para região, de modo que se possa estabelecer uma estratégia de controle adequada.bitstream/item/81556/1/insetos-acaros-Alba-Farias-Circular-Tecnica-14-1991.pdfMemória

Hamiltonian formulation of nonAbelian noncommutative gauge theories

We implement the Hamiltonian treatment of a nonAbelian noncommutative gauge theory, considering with some detail the algebraic structure of the noncommutative symmetry group. The first class constraints and Hamiltonian are obtained and their algebra derived, as well as the form of the gauge invariance they impose on the first order action.Comment: enlarged version, 7 pages, RevTe