Nuclear Level Density and the Determination of Thermonuclear Rates for Astrophysics

The prediction of cross sections for nuclei far off stability is crucial in the field of nuclear astrophysics. We discuss the model mostly employed for such calculations: the statistical model (Hauser-Feshbach). Special emphasis is put on the uncertainties arising from nuclear level density descriptions and an improved global description is presented. Furthermore, criteria for the applicability of the statistical model are investigated and a "map" for the applicability of the model to reactions of stable and unstable nuclei with neutral and charged particles is given.Comment: REVTeX paper + 7 B/W figures + 2 color figures; PRC, in press. Also available at http://quasar.physik.unibas.ch/preps.htm

SEMICLASSICAL QCD-LAGRANGIAN FOR NUCLEAR PHYSICS

Le Lagrangien QCD semiclassique donne correctement les limites du confinement et de la liberté asymptotique - contrairement à la limite classique du QCD. On discute l'application de la méthode sur la physique nucléaire en comparaison avec d'autres approximations de QCD.The semiclassical QCD-Lagrangian yields the correct limits of Confinement and asymptotic freedom in contrast to the Classical Limit. The applicability of the method to Nuclear Physics is discussed in comparison to other QCD-approximations

COMPUTER SIMULATION OF THE HIID FROM LANGMUIR-BLODGETT FILMS

Les processus de désorption en HIID (Heavy Ion Induced Desorption) sont simulés à l'aide d'une évaluation numérique directe des équations de mouvement des molécules. Ceci permet une meilleure comparaison des résultats expérimentaux aux modèles qui décrivent comment les forces effectives sur les molécules sont produites à partir d'une excitation électronique initiale. Nos calculs reproduisent sans ajustement de paramètres quelques aspects caractéristiques de HIID qui ont été trouvés dans des expériences avec des cibles Langmuir-Blodgett, telles que la dépendance des rendements avec les épaisseurs de films et l'énergie électronique perdue.The desorption process in HIID is simulated by direct numerical evaluation of the molecular equations of motion. This allows a better comparison of experimental data to models which describe how effective forces on the molecules are produced from an initial electronic excitation. Our calculations reproduce without parameter fitting some characteristic features of HIID which have been found in experiments with Langmuir-Blodgett targets, such as the dependence of yields from layer thickness or from electronic energy loss

Pertinent Strategy Issues in Scientific Information and Communication in 2004

In this article we will discuss some broader developments in the field of scientific information with the aim to determine and analyse some of the pertinent strategic issues that the stakeholders will face at present time. The stakeholders in the value chain of scientific information are: the user as author, reader and reviewer; the institution with which these users are affiliated; the publisher and the library as the main intermediaries; and other intermediaries such as subscription agents, providers and so on. We will look at these strategic issues from different stakeholder perspectives and we will attempt to make a comparison of these perspectives under the premise that these issues are relevant to further developments in library science