The bound-state level structures of the ${}_{\\ensuremath{\\Lambda}}^{16}$O and ${}_{\\ensuremath{\\Lambda}}^{15}$N hypernuclei were studied by \\ensuremath{\\gamma}-ray spectroscopy using a germanium detector array (Hyperball) via the $^{16}\\mathrm{O}$ (${K}^{\\ensuremath{-}},{\\ensuremath{\\pi}}^{\\ensuremath{-}}\\ensuremath{\\gamma}$) reaction. A level scheme for ${}_{\\ensuremath{\\Lambda}}^{16}$O was determined from the observation of three \\ensuremath{\\gamma}-ray transitions from the doublet of states (${2}^{\\ensuremath{-}},{1}^{\\ensuremath{-}}$) at $~6.7$ MeV to the ground-state doublet (${1}^{\\ensuremath{-}},{0}^{\\ensuremath{-}}$). The ${}_{\\ensuremath{\\Lambda}}^{15}$N hypernuclei were produced via proton emission from unbound states in ${}_{\\ensuremath{\\Lambda}}^{16}$O. Three \\ensuremath{\\gamma} rays were observed, and the lifetime of the $1/{2}^{+};1$ state in ${}_{\\ensuremath{\\Lambda}}^{15}$N was measured by the Doppler shift attenuation method. By comparing the experimental results with shell-model calculations, the spin dependence of the $\\ensuremath{\\Lambda}N$ interaction is discussed. In particular, the measured ${}_{\\ensuremath{\\Lambda}}^{16}$O ground-state doublet spacing of $26.4\\ifmmode\\pm\\else\\textpm\\fi{}1.6\\ifmmode\\pm\\else\\textpm\\fi{}0.5$ keV determines a small but nonzero strength of the $\\ensuremath{\\Lambda}N$ tensor interaction.

Gamma rays from the decays of $^{50}\mathrm{Sc}$, $^{50}\mathrm{Sc}^{m}$, $^{50}\mathrm{Ca}$, and $^{47}\mathrm{K}$, produced by $^{48}\mathrm{Ca}$+t reactions at ${E}_{\mathrm{t}}=3.2$ MeV, were investigated with a Ge(Li) detector. A 3.5-MV Van de Graaff and a rabbit target-transfer system were used. Precision energy measurements resulted in the following $\ensuremath{\gamma}$-ray energies (in keV): $^{50}\mathrm{Sc}$, 523.792(18), 1121.124(5), and 1553.768(8); $^{50}\mathrm{Ca}$, 71.552(5), 256.894(10), 1519.300(20), and 1590.850(30). Relative $\ensuremath{\gamma}$-ray intensities were also measured and more accurate ${\ensuremath{\beta}}^{\ensuremath{-}}$ and $\ensuremath{\gamma}$-ray branches in the decay schemes of $^{50}\mathrm{Sc}$, $^{50}\mathrm{Ca}$, and $^{47}\mathrm{K}$ were obtained. Limits were set on unobserved branches and, in $^{50}\mathrm{Sc}$ decay, five new ${\ensuremath{\beta}}^{\ensuremath{-}}$ branches were found. By using a short timing cycle it was found that a possible ${\ensuremath{\beta}}^{\ensuremath{-}}$ branch from $^{50}\mathrm{Sc}^{m}$ to the ${2}^{+}$ 1554-keV state of $^{50}\mathrm{Ti}$ is 2.5%. An incidental result was a value of 520.436(15) keV for the lowest energy $\ensuremath{\gamma}$ ray in $^{83}\mathrm{Rb}$ decay. The ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of $^{50}\mathrm{Sc}$ is compared to shell-model predictions.

Gamma rays from the decays of /sup 50/Sc, /sup 50/Sc/sup m/, /sup 50/Ca, and /sup 47/K, produced by /sup 48/Ca+t reactions at E/sub t/ = 3.2 MeV, were investigated with a Ge(Li) detector. A 3.5-MV Van de Graaff and a ''rabbit'' target-transfer system were used. Precision energy measurements resulted in the following ..gamma..-ray energies (in keV): /sup 50/Sc, 523.792(18), 1121.124(5), and 1553.768(8); /sup 50/Ca, 71.552(5), 256.894(10), 1519.300(20), and 1590.850(30). Relative ..gamma..-ray intensities were also measured and more accurate ..beta../sup -/ and ..gamma..-ray branches in the decay schemes of /sup 50/Sc, /sup 50/Ca, and /sup 47/K were obtained. Limits were set on unobserved branches and, in /sup 50/Sc decay, five new ..beta../sup -/ branches were found. By using a short timing cycle it was found that a possible ..beta../sup -/ branch from /sup 50/Sc/sup m/ to the 2/sup +/ 1554-keV state of /sup 50/Ti is <2.5%. An incidental result was a value of 520.436(15) keV for the lowest energy ..gamma.. ray in /sup 83/Rb decay. The ..beta../sup -/ decay of /sup 50/Sc is compared to shell-model predictions.

trench water from West Valley, New York, may be associated with organic molecules as species with molecular weight less than 700, and that it is unlikely an EDTA complex.

The ground-state nuclear pair decay branch from the 7.65-MeV ${0}^{+}$ level in $^{12}\mathrm{C}$ has been measured using the reaction $^{12}\mathrm{C}(p,{p}^{\ensuremath{'}})^{12}\mathrm{C}$ on a 3.5-mg/${\mathrm{cm}}^{2}$ thick carbon target at ${E}_{p}=10.5$ MeV together with a magnetic pair spectrometer. For normalization the internal pair line due to the 4.44-MeV $E2$ transition from the first-excited state of $^{12}\mathrm{C}$ was used. In separate measurements the corresponding relative populations of the 7.65- and 4.44-MeV states were determined. The angular distribution of the 4.44-MeV $\ensuremath{\gamma}$ rays was also measured in order to obtain the correction to the spectrometer efficiency due to nuclear alignment. A pair decay branch of (7.1 \ifmmode\pm\else\textpm\fi{} 0.8) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}6}$ was obtained for the 7.65-MeV level in agreement with, but somewhat more accurate than previous measurements.NUCLEAR STRUCTURE $^{12}\mathrm{C}$, 7.65-MeV state; measured $\frac{{\ensuremath{\Gamma}}_{\ensuremath{\pi}}}{\ensuremath{\Gamma}}$; deduced ${\ensuremath{\Gamma}}_{\mathrm{rad}}$.

$^{54}\mathrm{V}$ and the previously unreported $^{55}\mathrm{V}$ have been produced in the $^{48}\mathrm{Ca}(^{9}\mathrm{Be},2np)^{54}\mathrm{V}$ and $^{48}\mathrm{Ca}(^{9}\mathrm{Be},np)^{55}\mathrm{V}$ reactions at 20-MeV beam energy, and the subsequent $\ensuremath{\beta}$ decays to $^{54}\mathrm{Cr}$ and $^{55}\mathrm{Cr}$ have been studied via delayed $\ensuremath{\gamma}$-ray singles and $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ and $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ coincidence techniques. We measure the half-lives of $^{54\ensuremath{-}55}\mathrm{V}$ to be 49.82 \ifmmode\pm\else\textpm\fi{} 0.46 and 6.54 \ifmmode\pm\else\textpm\fi{} 0.15 sec, respectively. From analysis of the $\ensuremath{\beta}$-ray energy spectrum, a mass excess of -49152 \ifmmode\pm\else\textpm\fi{} 100 keV is determined for $^{55}\mathrm{V}$. Comparison with theoretical mass predictions is made.RADIOACTIVITY $^{54\ensuremath{-}55}\mathrm{V}$: measured delayed ${E}_{\ensuremath{\gamma}}$, ${I}_{\ensuremath{\gamma}}$, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidences; deduced ${T}_{\frac{1}{2}}$, decay scheme; measured $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ coincidences; deduced ${E}_{0}$, mass excess, $log\mathrm{ft}$; compared with theory. Enriched targets, Ge(Li) detectors.

$^{34}\mathrm{Si}$ has been produced via the $^{18}\mathrm{O}(^{18}\mathrm{O}, 2p)^{34}\mathrm{Si}$ reaction at 32 MeV beam energy. Identification is made from the observed $\ensuremath{\gamma}$ rays of energies 429.07(13) and 1607.56(50) keV, which agree with the known excitation energies of the first two excited states of $^{34}\mathrm{P}$, and from the cascade 1178.52(16)-keV transition. The three $\ensuremath{\gamma}$ rays decay with a common half-life of 2.77 \ifmmode\pm\else\textpm\fi{} 0.20 sec. Relative $\ensuremath{\gamma}$-ray intensities indicate a 100% $\ensuremath{\beta}$-ray branch to the 1608-keV level, and the $\ensuremath{\gamma}$-ray branches of that level are determined. No information is obtained on a possible $^{34}\mathrm{Si}$ ground-state $\ensuremath{\beta}$-ray branch. From analysis of the $\ensuremath{\beta}$-ray energy spectrum, a mass excess of - 19850 \ifmmode\pm\else\textpm\fi{} 300 keV is determined for $^{34}\mathrm{Si}$. Comparison with theoretical mass predictions is made.RADIOACTIVITY $^{34}\mathrm{Si}$: measured ${T}_{\frac{1}{2}}$, ${I}_{\ensuremath{\gamma}}$ deduced decay scheme; measured $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ coincidences; deduced ${E}_{0}$,, mass excess, $log\mathrm{ft}$; compared with theory.

$^{17}\mathrm{F}$ was made in the $^{16}\mathrm{O}(d,n)^{17}\mathrm{F}$ reaction, using a target of ${\mathrm{Ta}}_{2}$${\mathrm{O}}_{5}$ enriched in $^{16}\mathrm{O}$, and its half-life was measured by detecting $\ensuremath{\beta}$ rays in a plastic scintillator. A value of 64.80 \ifmmode\pm\else\textpm\fi{} 0.12 sec was obtained in agreement with an earlier but less accurate measurement.RADIOACTIVITY $^{17}\mathrm{F}$: measured ${T}_{\frac{1}{2}}$.

$^{22}\mathrm{F}$ was produced in the $^{18}\mathrm{O}(^{6}\mathrm{Li},2p)^{22}\mathrm{F}$ reaction using 26-MeV $^{6}\mathrm{Li}^{3+}$ ions. Following transfer of the target in a shuttle system, delayed $\ensuremath{\gamma}$ and $\ensuremath{\beta}$ rays were observed with Ge(Li) and NE102 plastic detectors. Several $\ensuremath{\gamma}$ rays from $^{22}\mathrm{F}$ decay were observed, decaying with a half-life of 4.23 \ifmmode\pm\else\textpm\fi{} 0.04 sec. $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence measurements have established that a 1900.0-keV transition terminates on a level in $^{22}\mathrm{Ne}$ at 5523.4 keV, contrary to a previous study. The ground state of $^{22}\mathrm{F}$ is of ${J}^{\ensuremath{\pi}}={4}^{+}$ (with ${3}^{+}$ as a remote possibility) disagreeing with a previous assignment of ${5}^{+}$. Accurate excitation energies are presented for seven states in $^{22}\mathrm{Ne}$. Experimental results compare favorably with full $2s\ensuremath{-}1d$ basis shell-model calculations of the $A=22$ system.[RADIOACTIVITY $^{22}\mathrm{F}$; measured ${t}_{\frac{1}{2}}$, ${E}_{\ensuremath{\gamma}}$, ${I}_{\ensuremath{\gamma}}$, ${E}_{\ensuremath{\beta}}$, $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coin., $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\beta}$ coin., deduced decay scheme, $J$ of $^{22}\mathrm{F}$, $log\mathrm{ft}$, ${E}_{\mathrm{levels}}$; compared with theory.]

The first reported measurements of the $\ensuremath{\beta}$ decay, half-life, and mass of $^{31}\mathrm{Al}$ are presented. The new activity was produced by the $^{18}\mathrm{O}(^{18}\mathrm{O}, \ensuremath{\alpha}p)^{31}\mathrm{Al}$ reaction using 41-MeV incident $^{18}\mathrm{O}$ ions, and was transferred pneumatically to a remotely located station where delayed $\ensuremath{\gamma}$ rays and $\ensuremath{\beta}$ rays were counted with Ge(Li) and NE 102 detectors, respectively. $\ensuremath{\gamma}$-ray energies (in keV) and relative intensities for the $^{31}\mathrm{Si}$ daughter transitions are 621.81\ifmmode\pm\else\textpm\fi{}0.30 (9.94\ifmmode\pm\else\textpm\fi{}0.65), 752.23 \ifmmode\pm\else\textpm\fi{}0.30 (18.5\ifmmode\pm\else\textpm\fi{}0.8), 1564.49\ifmmode\pm\else\textpm\fi{}0.30 (17.3\ifmmode\pm\else\textpm\fi{}1.6), 1694.73\ifmmode\pm\else\textpm\fi{}0.30 (58.9\ifmmode\pm\else\textpm\fi{}1.6), and 2316.64\ifmmode\pm\else\textpm\fi{}0.40 (72.8\ifmmode\pm\else\textpm\fi{}1.8). The $^{31}\mathrm{Si}$ excitation energies (in keV) and relative $\ensuremath{\beta}$ branching intensities are 752.24\ifmmode\pm\else\textpm\fi{}0.30 (3.0), 1694.78\ifmmode\pm\else\textpm\fi{}0.30 (49.0\ifmmode\pm\else\textpm\fi{}1.7), and 2316.73\ifmmode\pm\else\textpm\fi{}0.40 (100\ifmmode\pm\else\textpm\fi{}2.5). A tentative $\ensuremath{\beta}$- ray transition to a state at ${E}_{x}=2787.7\ifmmode\pm\else\textpm\fi{}0.8$ keV is also observed. Upper limits on the strength of some possible $\ensuremath{\gamma}$-ray transitions following $\ensuremath{\beta}$ decay to higher levels are given. $^{31}\mathrm{Al}$ decays with a half-life of 644\ifmmode\pm\else\textpm\fi{}25 msec. By measuring the energy spectra of $\ensuremath{\beta}$ rays populating the second and third excited states of $^{31}\mathrm{Si}$ the mass excess of $^{31}\mathrm{Al}$ has been measured to be -15008\ifmmode\pm\else\textpm\fi{}100 keV. The mass excess of $^{34}\mathrm{P}$ has been remeasured by a similar technique to be -24 550\ifmmode\pm\else\textpm\fi{}90 keV, and this value has been used to revise previous predictions for the masses of $^{33}\mathrm{Si}$ and $^{35}\mathrm{P}$. The masses of several ${T}_{z}=\frac{5}{2}$ and ${T}_{z}=3$ nuclides in the $2s\ensuremath{-}1d$ shell are compared with theoretical estimates. The $\ensuremath{\beta}$-decay measurements for $^{31}\mathrm{Al}$ are shown to be in poor agreement with simple collective-model calculations, and in good agreement with recent detailed shell-model calculations.