S-process studies with improved cross sections

New experimental techniques for the determination of neutron capture cross sections, e.g. the Karlsruhe 4 pi Barium Fluoride Detector, have reduced the respective uncertainties by a factor five compared to previous methods. With these improved data, detailed analyses of branchings in the s-process path allow the authors to derive constraints on the physical parameters during the s-process. As first examples, the neutron capture cross sections of the s-only isotopes of tellurium and samarium have been determined. The authors discuss the results in the framework of the classical s-process approach and with a stellar model describing the s-process during helium shell burning in low mass stars. The results for tellurium confirm the prediction of the classical approach of a 'local approximation' within the experimental uncertainty of 1%.