Stellar Synthesis of the Proton-Rich Heavy Elements

The heavy elements mixture and the stellar cluster age

Recent analyses of solar spectroscopic data (see Asplund, Grevesse & Sauval 2004 and references therein) suggest a significative variation of the heavy elements abundance. We discuss the effects of updating the metal distribution on theoretical evolutionary tracks and isochrones for metallicities suitable for the galactic globular and open clusters and for the bulk population of the Large Magel...

comparison of catalytic activity of heteropoly compounds in the synthesis of bis(indolyl)alkanes.

heteropoly acids (hpa) and their salts have advantages as catalysts which make them both economically and environmentally attractive, strong br?nsted acidity, exhibiting fast reversible multi-electron redox transformations under rather mild conditions, very high solubility in polar solvents, fairly high thermal stability in the solid states, and efficient oxidizing ability, so that they are imp...

Chemical Evolution of Heavy Elements in the Early Galaxy: Implications for Stellar Sources

An overview of the sources for heavy elements in the early Galaxy is given. It is shown that observations of abundances in metal-poor stars can be used along with a basic understanding of stellar models to guide the search for the source of the heavy r-process nuclei (r-nuclei). Observations show that this source produces very little of the elements from C through Zn including Fe. This strongly...

Fission barriers in the neutron-proton isospin plane for heavy neutron-rich nuclei

The dipole response of proton-rich nuclei

We propose to search for proton dipole pygmy resonances in nuclei near the proton drip line. Experimental evidence only exists for neutron pygmy resonances, but calculations infer the occurrence of proton pygmy resonances in proton-rich nuclei in the mass region A = 30 – 50. According to recent RQRPA calculations, low-lying E1 transitions, well below the giant dipole resonance, reveal the dynam...