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The relative abundances of the isotopes of zirconium, determined from the isotopic splitting of the /sup 1/Pi-/sup 1/..sigma.. (0,1) band head of ZrO, have been found for the two S stars R Cygni and V Cancri to be /sup 90/Zr:/sup 91/Zr:/sup 92/Zr:/sup 93/Zr:/sup 94/Zr:/sup 96/Zr = 0.47:0.10: 0.17:0.06:0.20:0.00. The nonzero abundance of /sup 93/Zr indicates that nucleosynthesis has taken place in these two stars within the recent past. Assuming that all of the above isotopes with the exception of /sup 96/Zr have been synthesized in the s-process, these abundances are consistent with all of the most common scenarios of s-process nucleosynthesis. Subject headings: nucleosynthesis--stars: abundances--stars: individual--stars: S-type

New measurements of the energies and the intensity ratio of the two $\ensuremath{\gamma}$ rays which are emitted following the $\ensuremath{\beta}$ decay of $^{37}\mathrm{S}$ to $^{37}\mathrm{Cl}$ are reported. The more accurate energies are 3102.7 (\ifmmode\pm\else\textpm\fi{}0.3) keV and 3706(\ifmmode\pm\else\textpm\fi{}2) keV, and the revised intensity of the 3706-keV radiation relative to the 3102.7-keV radiation is 0.012(\ifmmode\pm\else\textpm\fi{}0.003). The revised $log\mathrm{ft}$ value for the $\ensuremath{\beta}$ transition to the 3706-keV level of $^{37}\mathrm{Cl}$ is now in better agreement with a recent shell-model calculation.

A detailed investigation of the beta decay of 134Cs was made by means of a magnetic spectrometer employing an energy selection technique which provides a high degree of discrimination against scattering and background. A careful analysis of the beta groups populating the 1401 and 1643 keV levels in 134Ba reveals that each of them has an essentially statistical shape. The endpoint energies, intensities, and log10ft values for the five beta groups are: 89 keV (27±2%, 6.4), 415 keV (3.0±0.5%, 9.5), 658.0±0.4 keV (70±2%, 8.8), 891 keV (0.045±0.015%, 11.7±0.2), and 1454 keV (0.008±0.004%, 13.3±0.3). The Qβ value is 2058.5±0.4 keV.

Neutron capture cross sections were measured for seven tin isotopes (116 to 120, 122, and 124) with 30-kev neutrons. The abundances of the tin isotopes due to giantstar and supernovae nucleosynthesis are calculated, and the product of the abundance and cross section is ap proximately constant for all the isotopes, in agreement with the predicted inverse proportionality. The increased importance of the r-process (supernovae neutron capture) relative to the s- process (giant star neutron capture) is shown.