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In this study, the influence of UVC radiation and the influence of ozone on the surface energy of specimens made of polycarbonate were investigated. In an additional step, the peeling resistance of silicone flaps, which were overmolded, onto pre-treated PC plates of multicomponent specimens were analyzed. For this purpose, the samples were exposed to UVC radiation for different lengths of time, ranging from 5 s to 3 600 s. To further evaluate the influence of the ozone created by the UVC in the presence of oxygen, treatments were also performed in pure oxygen and nitrogen atmospheres. Contact angle measurements as well as analyses of the surface roughness were carried out to evaluate the effect of the treatment. Two phenomena were identified during the investigations. In room air and oxygen atmospheres, a short-term effect of UVC radiation was observed, which led to an increase in the surface energy, and, therefore, also to an increase in the wettability after an exposure time of only 10 s. In addition, a long-term effect was also found when tests were performed in a nitrogen atmosphere. This effect became visible after at least 60 s, and increased over the course of the duration exposure. The surface roughness of the polycarbonate plates increased up to about 60 % after 10 s of UVC exposure time in an air atmosphere, after 300 s of exposure to UVC radiation the roughness values had more than doubled. A modular injection molding tool was designed for the production of multi-component specimens. In this tool, a thermoplastic plate is molded on the one side, and is then automatically transferred by a robot system to be overmolded with silicone on the other side. The employed injection molding technique makes an intermediate treatment, such as surface activation of the thermoplastic plate, possible before it is overmolded. Also, the short-term and long-term effects of UVC treatment were able to be verified again for the peeling resistance of the material. These tests were only carried out for specimens treated in air.

Internal heat exchangers are often employed in solar thermal applications as well as in many other applications that involve heat, and, for the most part, consist of metallic materials (copper, stainless steel). Corrugated stainless steel tubes are easy to assemble, and are commonly used in various storage geometries. In order to significantly reduce costs, alternative materials, such as plastics, can function as excellent substitutes. Alternative heat exchangers for the following examinations using various materials and an extrusion process were produced. Subsequently, the heat exchangers were examined in regards to the heat they transfer. The heat transfer coefficient and the thermal conductivity of all materials were determined.

Multi-component injection moulding of liquid silicone rubbers (LSRs) in combination with thermoplastics is becoming increasingly important in plastics processing. This is also increasing the need to combine previously incompatible materials economically. This article shows how materials available on the market can be quickly combined in an injection-moulding process using a relatively simple pretreatment method – UV irradiation. In addition, this article discusses how long the activity of the pretreatment method persists and what effect this has on the adhesive bond. Finally, it is shown how partial adhesion of LSR to polycarbonates can be achieved.

Gef��rdert im Rahmen des Projekts DEAL, Federal Ministry for Economics and Technology (BMWi). Grant Number: 03THW10K14

A novel neutron spin-echo spectrometer with superconducting main coils enabling enclosure by a double walled mu-metal magnetic shielding chamber has been built and set into operation at the spallation neutron source in Oak Ridge. The layout of the spectrometer is described. Performance with emphasis on the superconducting main solenoids and the time-of-flight operation is described. Data on resolution, stability and first experiments are shown. (C) 2012 Elsevier B.V. All rights reserved.

Ultra-short proton pulses originating from laser-plasma accelerators can provide instantaneous dose rates at least 107-fold in excess of conventional, continuous proton beams. The impact of such extremely high proton dose rates on A549 human lung cancer cells was compared with conventionally accelerated protons and 90 keV X-rays. Between 0.2 and 2 Gy, the yield of DNA double strand breaks (foci of phosphorylated histone H2AX) was not significantly different between the two proton sources or proton irradiation and X-rays. Protein nitroxidation after 1 h judged by 3-nitrotyrosine generation was 2.5 and 5-fold higher in response to conventionally accelerated protons compared to laser-driven protons and X-rays, respectively. This difference was significant (p

In order to investigate the polarization degree of laser-accelerated \(^3\mathrm{He}\) ions from a polarized \(^3\mathrm{He}\) gas–jet target, several challenges have to be overcome. One of these is the development of an appropriate polarized \(^3\mathrm{He}\) gas–jet target. Since our experiments are carried out at the PHELIX Petawatt Laser Facility, GSI Darmstadt, the layout of the setup has to cope with the available space within the PHELIX target chamber. The essential components of such a layout are a magnetic holding field for storing polarized \(^3\mathrm{He}\) gas inside the vacuum chamber for many hours, the gas–jet source for providing the desired laser target, and finally, a polarimeter for measuring the spin-polarization degree of laser-accelerated \(^3\mathrm{He}^{2+}\) ions.

The release fraction of implanted 12 keV 37 K ( T 1 / 2 =1.23 s) ions from a variety of catcher foils was measured. The temperature dependence was measured for V, Fe, Ni, Y, Zr, Nb, Mo, Hf, Ta, W, Re, C, and Pt foils. The release fraction was found empirically to be a reasonably universal function of the ratio of temperature to catcher melting point. Limits on diffusion parameters (ignoring desorption) and on desorption (ignoring diffusion) were deduced. The results were used to find the optimal neutralizing catcher foil to load a neutral atom trap, and can be used to help choose ISOL target production materials.

Laser trapping and cooling techniques are now being applied to the study of nuclear beta-decay at several labs. A magneto-optical trap (MOT) provides a localized source of atoms suspended in space, so the low-energy recoiling nuclei can freely escape and be detected in coincidence with the beta. This allows reconstruction of the neutrino momentum, and the deduction of the beta-nu correlation in a more direct fashion than previously possible. In addition, the nuclei can be polarized by atomic techniques, opening a new class of spin-correlation measurements to test the degree to which parity is maximally violated in the weak interaction. Our present experiment has detected several hundred thousand recoil-beta(+) coincidences from the 0(+) --> 0(+) pure Fermi decay of K-38m, produced at the on-line isotope separators TISOL and ISAC at TRIUMF. Our goal is to set constraints on non-Standard Model scalar bosons competitive with high-energy colliders and more conventional beta-nu correlation experiments.

A segmented neutron detector has been constructed and used for recoil neutron (6–13 MeV) measurements of the reaction γp→nπ+ very close to threshold. BC-505 liquid scintillator was used to allow pulse shape discrimination between neutrons and photons. A measurement of the absolute efficiency of the detector was performed using stopped pions in the reaction π−p→nγ. Results of the efficiency calibration are compared to a Monte Carlo simulation.

The α-particle energy loss method (AEL) has been implemented in situ to monitor film thickness and composition during growth of GaAs, InP and LaF 3 based materials by molecular beam epitaxy (MBE). In the AEL method, a 228 Th source is used to recoil implant a 5 mm diameter region of the surface of the wafers with the α-emitter daughter isotope 224 Ra prior to growth. The implanted nuclei decay with a half life of 3.7 days through a sequence of daughters which emit alpha particles at different energies. Deposition on the surface causes the emission lines to be shifted to lower energies due to energy loss in the film. For substrates marked with a low activity (∼ 30 kBq; similar to activity of smoke detectors) we are able to measure film thickness with ± 6 nm uncertainty and growth rate with ± 0.01 nm/s uncertainty in real time. By measuring the relative growth rates of the different materials, AEL also allows us to infer the composition of a ternary laver film as well as the sticking coefficients rates directly at different growth temperatures.

A thin 42 μCi 44 Ti (t 1/2 =62 yr ) target has been prepared for the study of the 44 Ti (p, γ ) 45 V reaction. The target areal density is 1.9×1016 44 Ti atoms cm−2. Naturally occurring Ti from the scandium source material contaminates the target at an areal density of 1.2×1019 atoms cm−2. The target consists most probably in the chemical form of the TiO2 deposited onto a Ta backing. The target area is 0.20 cm2. The chemical extraction and fabrication procedures used in the preparation of the target were of high efficiency. Overall, the target was prepared with an efficiency of 80%.

We have studied the $\ensuremath{\beta}$-delayed particle decay of ${}^{17}$Ne to test the feasibility of determining both the $E1$ and $E2$ components of the ${}^{12}$C$(\ensuremath{\alpha},\ensuremath{\gamma}{)}^{16}$O cross section at energies relevant to helium burning in stars. In this context we have observed the breakup of the isobaric analog state in ${}^{17}$F at 11.193 MeV into three particles via three channels: proton decay to the 9.59 MeV state in ${}^{16}$O; and $\ensuremath{\alpha}$ decay to the 2.365 and 3.502/3.547 MeV states in ${}^{13}$N. This is the first reported observation of the decay of the IAS to the ${1}^{\ensuremath{-}}$ state in ${}^{16}$O at 9.59 MeV and the first reported $\ensuremath{\beta}$-delayed proton-$\ensuremath{\alpha}$ decay. With straightforward improvements to our detection apparatus to improve angular resolution, $\ensuremath{\beta}$ suppression, and solid angle coverage, we should be able to proceed to the measurement of the effect of the tail of the subthreshold state at 7.117 MeV in ${}^{16}$O on the $\ensuremath{\alpha}$ spectrum from the breakup of the 9.59 MeV state.

Magneto optical traps (MOT) allow the cooling and storing of neutral atoms in a volume of a few cubic millimeters by use of laser beams and a magnetic field. Such devices offer new and exciting opportunities for precision measurements of radioactive isotopes. Here we present experiments performed with a double-MOT system coupled to the on-line separator TISOL at TRIUMF/Vancouver, Canada. For the first time, the Β-decay of free atoms stored in such a device could be observed. We report on coincidence measurements between beta-particles and the argon recoils in the decay of 37K and 38rm{m}}K. The charge state ratios of the recoil-ions were deduced by Time-Of-Flight separation in an acceleration field. The final goal of those investigations is a precision test of the Standard Model by measuring the –nu-correlation parameter a.

A high-angle neutron fibre diffraction study of the hydration of A-DNA has been performed using the single-crystal diffractometer D19 at the Institut Laue-Langevin (Grenoble, France). The sample was prepared using deuterated DNA extracted from E. Coli cells cultured on deuterated nutrients. In common with our previous neutron fibre diffraction studies of DNA, this work exploits the ability to isotopically replace H2O around the DNA by D2O. However this study benefitted additionally from the fact that the hydrogen atoms which are covalently bonded to carbon atoms in the DNA sugars and bases were replaced by deuterium so that incoherent scattering and absorption effects were minimised. Successive cycles of Fourier synthesis and Fourier difference synthesis allowed water peaks to be identified and their positional and occupancy parameters to be refined against the observed diffraction data. The results confirm the main hydration features noted in our earlier studies with a clear network of water running along the inside edge of the major groove linking successive O1 phosphate oxygen atoms. The central core of water running along the axis of the double helix is very much clearer in this work. Additionally this study shows chains of ordered water lying in the centre of the major groove.

The α-particle energy loss method has been implemented in situ to monitor film thickness during growth by molecular beam epitaxy. For InP and GaAs substrates dosed with 500–1500 Bq of α-particle emitters, we have been able to measure thickness in situ of deposited GaAs and InP, to an accuracy of 6 nm in 180 s of counting time. The corresponding growth rate accuracy for growth rates on the order of 0.3 nm/s was ±0.01 nm/s. The accuracy and counting time improvements expected with the use of a stronger marking source are also discussed.

The β-delayed α-particle decay of 36K has been measured in order to search for natural parity states near the proton threshold in 36Ar. Such states could correspond to resonances in the reaction 35Cl(p,α)32S and might influence mass flows in explosive hydrogen burning scenarios appreciably. We have found evidence for a new α-particle emitting state, corresponding to a resonance energy of ERlab=351 keV. Possible implications for the nucleosynthesis during neon nova outbursts are discussed. Properties of the proton drip line nuclei 65As, 69Br and 73Rb are important for the prediction of the nucleosynthesis in very high-temperature hydrogen-burning scenarios, such as x-ray bursts. We describe an experimental program at TRIUMF which is designed to measure the quantities of astrophysical interest.

We have determined the branching ratios for the β-delayed proton decay of excited states in 17 F to excited states in 16 O by measuring proton-γ-ray coincidences. We have observed transitions to the 2 + state at 6.917 MeV in 16 O from 17 F states at 11.193, 10.0, 9.45, 8.83 and 8.44 MeV. In particular, the transition from the 9.45 MeV state is an order of magnitude stronger than the accompanying transitions to the 1 − state at 7.117 MeV and the 3 − state at 6.130 MeV, and seems a favourable case for the observation of 16 O break-up into α + 12 C .

The measurement of low energy fusion reactions of importance to nuclear astrophysics scenarios are a prime objective of the physics program of the new ISAC facility, located at TRIUMF in Vancouver, Canada. Intense radioactive beams of 19 Ne, 14,15 O, 20,21 Na, 17,18 F and other low Z species with energies in the range of 0.15 to 1.5 MeV/mass unit will be available to measure cross sections and resonance strengths of alpha and proton induced reactions. An important component of the experimental configuration will be a new Reaction Products Detection Facility (RPDF) consisting of a windowless gas target, surrounded by a gamma array, while the recoils are separated from the intense radioactive beam using a Recoil Mass Spectrometer (RMS). The RMS will be based on a Wien filter. The recoiling reaction products will then be detected using either a Si μ-strip array or a gas filled detector. Using these devices along with coincidence requirements and time of flight conditions a background reduction factor of the order of 10 +15 is the present goal.

A magneto-optic trap (MOT) can provide a well-polarized, backing-free, localized source of radioactive atoms for $\ensuremath{\beta}$-decay experiments. We have trapped approximately 6000 atoms of ${}^{38}{\mathrm{K}}^{m}$ ( ${t}_{1/2}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.925\mathrm{s}$) and 2000 atoms of ${}^{37}\mathrm{K}$ (1.226 s) produced at the TRIUMF on-line separator TISOL in a vapor-cell MOT. We have measured optical isotope shifts and deduced the nuclear charge radii, which show an unusual lack of change at the neutron number $N\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}20$ shell closure. Plans include a search for scalar contributions to the ${\ensuremath{\beta}}^{+}$- $\ensuremath{\nu}$ correlation in the ${0}^{+}\ensuremath{\rightarrow}{0}^{+}$ decay of ${}^{38}{\mathrm{K}}^{m}$.

The measurement of low energy fusion reactions of importance to nuclear astrophysics scenarios are a prime objective of the physics program of the new ISAC facility, located at TRIUMF in Vancouver, Canada. Intense radioactive beams of 19 Ne, 14,15 O, 20,21 Na, 17,18 F and other low Z species with energies in the range of 0.15 to 1.5 MeV/mass unit will be available to measure cross sections and resonance strengths of alpha and proton induced reactions. An important component of the experimental configuration will be a new Recoil Product Detection Facility (RPDF) consisting of a windowless gas target, surrounded by a gamma array, while the recoils are separated from the intense radioactive beam using a Electro-Magnetic Separator (EMS) employing Wien filters. The recoiling reaction products will then be detected using either a Si μ-strip array or a gas filled detector. Using these devices along with coincidence requirements and time-of-flight conditions a background reduction factor of the order of 10 +15 is the present goal.

A method for determining both the thickness and the average stoichiometry of thin films is presented. The method is based on implanting radioactive -sources in the substrate prior to layer growth and measuring the energy loss of the -particles as they traverse the layer. Information about the stoichiometry is obtained through the comparison of the energy loss of -particles of different initial energies. Experimental examples for the utilization of this method are presented, in which Sb was grown on Si substrates, GaAs, InAs and AlAs on GaAs and YBCO on YSZ. The experimental precision which can be expected using the method is discussed, together with specific scenarios in which it could be advantageously applied.

The track structure of ionizing radiation predominantly determines the biological effects after irradiation. A new detector to register 3D track structure segments in low pressure gas was proposed in a previous work. The device combines the operational principle of thick gas electron multipliers (THGEM), working in reverse polarity, and resistive plate chambers. In this work, the detector was further developed. Optimization of THGEM thickness, hole pitch and cathode resistivity were studied. A new detector prototype was built and tested with a microbeam providing different radiation qualities. The detector rate capability and ion collection efficiency were also investigated. Results show that the detector efficiency increases with increasing THGEM thickness and decreasing cathode resistivity. Preliminary results show that the ion collection efficiency is low and that the detector performance is limited by a long dead time. The detector is able to register single ions with a low dark rate. However, further development is needed in order to obtain the efficiency necessary to reconstruct 3D track structure.

The excitation energies of the proton unbound states in [sup 32]Cl have been measured in the [sup 32]S([sup 3]He,[ital t])[sup 32]Cl charge exchange reaction with high accuracy. The partial widths of the unbound levels have been calculated to derive the resonance strengths of these states in the [sup 31]S([ital p],[gamma])[sup 32]Cl reaction channel. The reaction rate for the [sup 31]S([ital p],[gamma])[sup 32]Cl reaction has been calculated and is compared with previous estimates. The role of this reaction for the closure of the SiP cycle is discussed in terms of the temperature and density conditions in hot stellar hydrogen burning.

The 18 O( 6 Li,d) 22 Ne α-transfer reaction has been used to study the level structure of 22 Ne around the α-threshold and to identify natural-parity states in that excitation range. The 18 O(α, γ) 22 Ne reaction has been studied in the energy range between 340 and 800 keV to determine the existence of possible resonances and to investigate their influence on the reaction rate of 18 O(α, γ) 22 Ne.

The new DRAGON facility at TRIUMF is designed to measure alpha and proton capture reactions with radioactive ion beams in inverse kinematics. For nucleo-synthesis in astrophysical scenarios, the relevant energies lie in the 0.15–1 MeV/u range, where very low cross sections are expected. Therefore the separation of the recoil products from the beam particles will be a difficult task. This paper focuses on the end detectors, which will be used to distinguish recoils from beam particles at the end of the DRAGON separator.

Proton-activation reactions on natural and enriched palladium samples were investigated via the activation technique in the energy range of E_p=2.75 MeV to 9 MeV, close to the upper end of the respective Gamow window of the gamma process. We have determined cross sections for 102Pd(p,gamma)103Ag, 104Pd(p,gamma)105Ag, and 105Pd(p,n)105Ag, as well as partial cross sections of 104Pd(p,n)104Ag^g, 105Pd(p,gamma)106Ag^m, 106Pd(p,n)106Ag^m, and 110Pd(p,n)110Ag^m with uncertainties between 3% and 15% for constraining theoretical Hauser-Feshbach rates and for direct use in gamma-process calculations., Comment: 12 pages, accepted for publication in Phys. Rev. C (2011)

The 22 Ne( 6 Li, d) α-transfer reaction has been used to search for α-unbound levels in 26 Mg of importance for resonant α-capture on 22 Ne in stellar helium burning. To determine the resonance strengths of the observed states the 22 Ne(α, n) 25 Mg reaction was investigated in the energy range between 600 and 900 keV. One resonance was identified and its strength determined. The astrophysical implications of the present results are discussed.

The low energy part of the beta delayed, alpha spectrum of ^(16)N can be used to determine the p-wave capture amplitude of the astrophysically important reaction ^(12)C(α ;y)^(16)O. Experimental details of a measurement of the emitted a spectrum in coincidence with the ^(12)C recoil nuclei, performed at the TRIUMF isotope separator, TISOL is presented.

The α spectrum following the β decay of 16N from the isotope separator TISOL has been measured by detecting 106 α particles in coincidence with 12C nuclei. These data, which show a low-energy interference anomaly accompanying the main α peak, permit a more precise determination of the p-wave amplitude of the astrophysically important reaction 12C(α,γ)16O. The α spectrum and previous γ-ray data have been fitted simultaneously by a K-matrix parametrization; a value of S(E=0.3 MeV)=57±13 keV b has been obtained for the E1 part of the 12C(α,γ)16O reaction.

The ^(32)S(p,γ)^(33)Cl reaction has been measured in the proton-energy range E_p = 0.4–2.0 MeV. Non-resonant γ-transitions were observed to the final states in ^(33)Cl at E_x = 0,811 and 2846 keV. The corresponding spectroscopic factors have been extracted from fits to the excitation functions and are compared to values from stripping data as well as theoretical model calculations. The astrophysical aspects of the ^(32)S(p,γ)^(33)Cl reaction are also discussed.

The s process synthesizes the elements between Fe and Sr in massive stars during two major evolutionary stages, convective core He burning and C shell burning. This scenario implies fascinating consequences for the chemical evolution of the star. For instance, the neutron capture rate at each isotope can have a big influence on the production of many of the subsequent higher mass isotopes. Correspondingly, one needs to know the (n,γ) cross sections of the involved isotopes with high accuracy in order to determine the abundance pattern reliably and to obtain a consistent picture of this stage. This contribution gives an overview on recent and future experiments for the Fe/Ni nucleosynthesis in massive stars. New results on 60Fe, 62Ni and 64Ni are reported. 60Fe is mostly produced during the short convective C shell burning phase, where peak densities of ∼1011 cm−3 are reached, prior to the SN explosion. The stellar (n,γ) cross section of 60Fe could be measured with a 1 μg sample obtained at PSI (Switzerlan...

The reactions ^(31)P(p, γ)^(32)S and ^(31)P(p, α)^(28)Si have been studied in the energy range 280–620 keV to investigate the influence of low-energy resonances on the stellar reaction rates. Several new resonances have been observed and the resonance strengths for both reaction channels have been determined. The reaction rates have been calculated from the present results and are compared with the results of Hauser-Feshbach calculations.

The α-particle energy loss method (AEL) has been implemented in situ to monitor film thickness during growth by molecular beam epitaxy. For InP and GaAs substrates recoil implanted with α-particle emitters, we have been able to measure thickness and composition of deposited GaAs, AlGaAs and InGaAs in real time. The AEL method yields in situ real time results comparable in accuracy to those obtained by ex situ scanning electron microscope and high-resolution x-ray diffraction measurements.

We have set limits on contributions of scalar interactions to nuclear beta decay. A magneto-optical trap (MOT) provides a localized source of atoms suspended in space, so the low-energy recoiling nuclei can freely escape and be detected in coincidence with the beta. This allows reconstruction of the neutrino momentum, and the measurement of the beta-neutrino correlation, in a more direct fashion than previously possible. The beta-neutrino correlation parameter of the 0+ to 0+ pure Fermi decay of 38mK is $\tilde{a}$=0.9981+-0.0030+-0.0037, consistent with the standard model prediction a=1. Comment: 4 pages, 3 figures, accepted by Phys. Rev. Lett., centroid changed

Techniques for recording and analysing fibre diffraction data from DNA using the instrument D19 at the Institut Laue-Langevin Reactor Source and the instrument SXD at the Rutherford Appleton Laboratory ISIS Spallation Source are described and compared. Data recorded from a specially prepared sample of deuterated DNA in the A conformation using SXD are compared with previously analysed data from a normally hydrogenated DNA in the same conformation recorded on D19. A preliminary Fourier difference analysis of these two datasets has allowed their consistency to be established.

A new technique, full neutrino momentum reconstruction, is used to set limits on the admixture of heavy neutrinos into the electron neutrino. We measure coincidences between nuclear recoils and positrons from the beta decay of trapped radioactive atoms and deduce the neutrino momentum. A search for peaks in the reconstructed recoil time-of-flight spectrum as a function of positron energy is performed. The admixture upper limits range from 4x10(-3) to 2x10(-2) and are the best direct limits for neutrinos (as opposed to antineutrinos) for the mass region of 0.7 to 3.5 MeV.

A new technique, full neutrino momentum reconstruction, is used to set limits on the admixture of heavy neutrinos into the electron neutrino. We measure coincidences between nuclear recoils and positrons from the beta decay of trapped radioactive atoms and deduce the neutrino momentum. A search for peaks in the reconstructed recoil time-of-flight spectrum as a function of positron energy is performed. The admixture upper limits range from 4 x 10(-3) to 2 x 10(-2) and are the best direct limits for neutrinos (as opposed to antineutrinos) for the mass region of 0.7 to 3.5 MeV.

The \ensuremath{\beta} delayed deuteron decay of ${}^{6}\mathrm{He}$ has been measured at the TISOL facility at TRIUMF. For the \ensuremath{\beta}-particle measurement a silicon-germanium telescope array has been used. To separate deuterons from $\ensuremath{\alpha}$ particles and to obtain the spectral form of the deuteron decay, a $d\ensuremath{-}\ensuremath{\alpha}$ coincidence technique has been employed using two opposite silicon detectors. The \ensuremath{\beta} branch has been determined from the geometry of the experiment and also by comparison with the well-known $\ensuremath{\beta}\ensuremath{-}\ensuremath{\alpha}$ decay modes of ${}^{16}\mathrm{N}$ and ${}^{8}\mathrm{Li}.$ A branching ratio of $(1.8\ifmmode\pm\else\textpm\fi{}0.9)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ above the $\ensuremath{\beta}$ cutoff (350-keV deuteron laboratory energy) and $(2.6\ifmmode\pm\else\textpm\fi{}1.3)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ for the entire spectrum has been determined for this decay. In the course of the measurement the half-life of ${}^{6}\mathrm{He}$ has been remeasured to be ${T}_{1/2}=0.810\ifmmode\pm\else\textpm\fi{}0.008 \mathrm{s}.$ High statistical accuracy in the deuteron spectrum has been obtained that allowed a comparison of the shape of the deuteron spectrum to theoretical predictions.

Angular distributions of ${}^{12}\mathrm{C}(\ensuremath{\alpha},\ensuremath{\alpha}{)}^{12}\mathrm{C}$ have been measured for ${E}_{\ensuremath{\alpha}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2.6--8.2\mathrm{MeV}$, at angles from $24\ifmmode^\circ\else\textdegree\fi{}$ to $166\ifmmode^\circ\else\textdegree\fi{}$, yielding 12 864 data points. R-matrix analysis of the ratios of elastic scattering yields a reduced width amplitude of ${\ensuremath{\gamma}}_{12}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.47\ifmmode\pm\else\textpm\fi{}0.06{\mathrm{MeV}}^{1/2}$ for the ${E}_{x}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}6.917\mathrm{MeV}({2}^{+})$ state in ${}^{16}\mathrm{O}(a\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5.5\mathrm{fm})$. The dependence of the ${\ensuremath{\chi}}^{2}$ surface on the interaction radius $a$ has been investigated and a deep minimum is found at ${a\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}5.42}_{\ensuremath{-}0.27}^{+0.16}\mathrm{fm}$. Using this value of ${\ensuremath{\gamma}}_{12}$, radiative $\ensuremath{\alpha}$ capture and ${}^{16}\mathrm{N}$ $\ensuremath{\beta}$-delayed $\ensuremath{\alpha}$-decay data, the S factor is calculated at ${E}_{\mathrm{c}.\mathrm{m}.}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}300\mathrm{keV}$ to be ${S}_{E2}(300){\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}53}_{\ensuremath{-}18}^{+13}\mathrm{keV}\mathrm{b}$ for destructive interference between the subthreshold resonance tail and the ground state $E2$ direct capture.

Angular distributions of 12C(alpha,alpha)12C have been measured for E(alpha) = 2.6-8.2 MeV, at angles from 24 to 166, yielding 12 864 data points. R-matrix analysis of the ratios of elastic scattering yields a reduced width amplitude of gamma12 = 0.47 +/- 0.06 MeV(1/2) for the Ex = 6.917 MeV (2+) state in 16O(a = 5.5 fm). The dependence of the chi2 surface on the interaction radius a has been investigated and a deep minimum is found at a = 5.42(+0.16)(-0.27) fm. Using this value of gamma12, radiative alpha capture and 16N beta-delayed alpha-decay data, the S factor is calculated at E(c.m.) = 300 keV to be S(E2)(300) = 53(+13)(-18) keV b for destructive interference between the subthreshold resonance tail and the ground state E2 direct capture.

The strengths of low-energy resonances in ${}^{14}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma}{)}^{18}\mathrm{F}$ at 573 keV and 1136 keV have been measured using an activation method. In addition, their relative strength and the energy of the lower resonance have been determined in a prompt $\ensuremath{\gamma}$-ray experiment. The results of these measurements are used to reevaluate the stellar reaction rate of ${}^{14}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma}{)}^{18}\mathrm{F}.$ The present reaction rate at temperatures of astrophysical interest is a factor of 2 smaller than previously reported.

The $\ensuremath{\beta}$ decay of ${}^{9}\mathrm{C}$ ${(T}_{1/2}=126.5 \mathrm{ms})$ has been studied in two experiments observing about $15\ifmmode\times\else\texttimes\fi{}{10}^{7}$ and $8\ifmmode\times\else\texttimes\fi{}{10}^{7}$ decays, respectively, at the TISOL facility at TRIUMF; different detector configurations were employed in the two experiments. In this first of two papers, the two experimental setups are described, as well as data analysis and a phenomenological approach to deducing branching ratios to and from states in ${}^{9}\mathrm{B}.$ In the experiments single spectra, and double and triple coincidence spectra, were recorded. Several states in ${}^{9}\mathrm{B}$ were observed; $\ensuremath{\beta}$-branching ratios to these states, and particle decay channels from these states, are reported. In particular, secondary decays into the ${}^{5}\mathrm{Li}$ and ${}^{8}\mathrm{Be}$ ground states were observed. With the inclusion of a considerable continuum and additional states, fair agreement with the reported ${}^{9}\mathrm{Li}\mathrm{log}\mathrm{ft}$ values is found with a phenomenological approach for deducing the branching ratios. To extend the discussion, in a second, forthcoming paper, a multichannel, multistate R-matrix analysis of these data will be described.