DPG Phi
Verhandlungen
Verhandlungen
DPG

Bochum 1998 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

HK: Hadronen und Kerne

HK 53: Nuclear Astrophysics IV

HK 53.3: Vortrag

Mittwoch, 18. März 1998, 14:45–15:00, G

R-Process Abundances and Cosmochronometers in Old Metal-Poor Halo Stars — •B. Pfeiffer1, K.-L. Kratz1, F.-K. Thielemann2, and J.J. Cowan31Inst. für Kernchemie, Universität Mainz, Germany — 2Inst. für Theoretische Physik, Universität Basel, Switzerland — 3Department of Physics and Astronomy, University of Oklahoma, USA

Recently, stellar abundances of neutron-capture elements (beyond iron) have been determined over a wide z-range in 4 very metal-poor Galactic halo stars using the GHR Spectrograph of the Hubble Telescope [1]. After adjustment to solar metallicity, the values for these first-generation stars are consistent with the global solar-system r-process abundances as well as with our recent ETFSI-Q predictions [2,3]. This agreement not only indicates a unique r-process scenario (at least beyond Z≃50), but also allows to make reliable extrapolations of the long-lived actinide cosmochronometers. With the measured Th and U abundances in the halo stars and our calculated values, lower limits for the decay age of the Galaxy can be derived independent of chemical-evolution models.

[1] C. Sneden et al., Ap.J. 467, 819 (1996), and Ap.J. in press

[2] B. Pfeiffer et al., Z. Phys. A357, 235 (1997)

[3] K.-L. Kratz et al., Proc. NN’97, Nucl. Phys. A, in press  work supported by BMBF (06MZ465)

100% | Mobil-Ansicht | English Version | Kontakt/Impressum/Datenschutz
DPG-Physik > DPG-Verhandlungen > 1998 > Bochum