ρ\rho - nucleus bound states in Walecka model

Possible formation of $\rho$ nucleus bound state is studied in the framework of Walecka model. The bound states are found in different nuclei ranging from $^3He$ to $^{208}Pb$. These bound states may have a direct bearing on the recent experiments on the photoproduction of $\rho$ meson in the nuclear medium.Comment: RevTeX fil

Many-body approach to proton emission and the role of spectroscopic factors

The process of proton emission from nuclei is studied by utilizing the two-potential approach of Gurvitz and Kalbermann in the context of the full many-body problem. A time-dependent approach is used for calculating the decay width. Starting from an initial many-body quasi-stationary state, we employ the Feshbach projection operator approach and reduce the formalism to an effective one-body problem. We show that the decay width can be expressed in terms of a one-body matrix element multiplied by a normalization factor. We demonstrate that the traditional interpretation of this normalization as the square root of a spectroscopic factor is only valid for one particular choice of projection operator. This causes no problem for the calculation of the decay width in a consistent microscopic approach, but it leads to ambiguities in the interpretation of experimental results. In particular, spectroscopic factors extracted from a comparison of the measured decay width with a calculated single-particle width may be affected.Comment: 17 pages, Revte

Z^* Resonances: Phenomenology and Models

We explore the phenomenology of, and models for, the Z^* resonances, the lowest of which is now well established, and called the Theta. We provide an overview of three models which have been proposed to explain its existence and/or its small width, and point out other relevant predictions, and potential problems, for each. The relation to what is known about KN scattering, including possible resonance signals in other channels, is also discussed.Comment: 29 pages, uses RevTeX4; expanded version (published form

Otherism in discourses, integration in policies?

In this study of educational policies aimed at migrants in France and Denmark, we examine how both countries display the same mixture of integration policies and of discourses of hostility portraying migrants as scapegoats. Educational policies are seen as a fundamental tool to speed up the integration of migrants, yet these are seen as a potential threat to national equilibrium and cohesion. This contradiction results from specific forms of policy construction and patterns of discursive spaces. This led us to argue, using the Foucauldian concept of governmentality, against a unified conception of the power yielded by the state on migrants