Seminar Details

Nuclear Astrophysics Constraining Cosmology

Rene Reifarth, University of Frankfurt
Monday, February 24, 12:30 PM - JINA Pizza Lunch
Biomedical & Physical Sciences Bldg., Rm. 1400

The destiny of the Universe is strongly coupled to the history of space and time. In particular the age of the Universe allows to constrain our models about the future. If the expansion of the Universe is accelerated it is currently older than if it would collapse again at some point in the distant future. Nuclear astrophysics provides tools to determine the age of the Universe independent from astronomical observations. This history of the Universe is imprinted in the isotopic abundance pattern of stable and, in particular, long-lived unstable nuclei. If the half-life of such isotopes is comparable to the Hubble time, they can be interpreted as cosmo-chronometers. A promising isotope is 87Rb, which decays on a time scale of 50 Gyr to 87Sr. The interpretation of this isotope as a cosmo-chronometer is currently hampered by the unknown neutron capture cross section of 85Kr, which decays with a half-life of 10 yr. The measurement of this cross section will soon be possible at the FRANZ facility at the Goethe University Frankfurt/Germany, which is currently under construction.