Diverse Supernova Sources for the r-Process and Abundances in Metal-Poor Stars

The dispersion and mean trends of r-process abundances in metal-poor stars are discussed based on a model of diverse supernova sources for the r-process. This model is unique in that its key parameters are inferred from solar system data independent of stellar observations at low metallicities. It is shown that this model provides a good explanation for the observed dispersion and mean trend of Eu abundances over -3 < [Fe/H] < -1. It is also shown that this model provides a means to discuss r-abundances in general. For example, the Ag abundance in any metal-poor star with observed Eu and Fe abundances can be calculated from the model. This approach is demonstrated with success for two stars and can be further tested by future Ag data. The dispersion and mean trend of Ag abundances in metal-poor stars are also calculated for comparison with future observations.Comment: 4 pages, 2 figures, to appear in ApJL (submitted February 1, 2001

Diffractive Theorems for the Wave Equation with Inverse Square Potential

We first establish the presence of a diffractive front in the fundamental solution of the wave operator with a diract delta intial condition in two dimensional euclidean space caused by the potentials perturbation on the spherical laplacian. This motivates a result which restricts the propagation of singularities for the wave operator with a more general potential to precisely these diffractive fronts higher dimensional euclidean spaces. This is proven using microlocal energy estimates.Comment: 41 pages, 6 figure

Neutrino-Induced Fission and r-Process Nucleosynthesis

An r-process scenario with fission but no fission cycling is considered to account for the observed abundance patterns of neutron-capture elements in ultra-metal-poor stars. It is proposed that neutrino reactions play a crucial role in inducing the fission of the progenitor nuclei after the r-process freezes out in Type II Supernovae. To facilitate neutrino-induced fission, the proposed r-process scenario is restricted to occur in a low-density environment such as the neutrino-driven wind from the neutron star. Further studies to develop this scenario are emphasized.Comment: 11 pages, 2 figures, to appear in ApJ

Globalization and the Output-Inflation Tradeoff: New Time Series Evidence

Recent cross-country studies on the globalization and output-inflation tradeoff correlation find openness has no significant effect on OECD countries. Those studies assume parameter constancy across countries. In this paper, we argue that this assumption does not hold for major industrialized countries. Using individual time series analysis, we find the effect of openness on the output-inflation trade off differ in sign and size across countries. In contrast to previous cross-country studies, we find globalization has significantly changed some major industrialized countries’ output inflation tradeoff. This has important implications for future theoretical and empirical research.openness;output-inflation tradeoff;Phillips curve;time inconsistency theory