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Atomic beam devices are frequently equipped with sextupole magnets to focus the beam or to act as spin filters in combination with RF-transitions for manipulating the hyperfine population within the atomic beam. A useful tool for the analysis of sextupole systems, the application of time-of-flight (TOF) measurements is presented. TOF measurements are enabled without mechanical beam chopper by utilizing adiabatic radio frequency transitions to select atoms within a certain time interval. This method is especially interesting for the use in atomic beam devices that are already equipped with RF-transitions and sextupole magnets and where space limitations or the required quality of the vacuum do not allow the installation of a mechanical chopper. The measurements presented here were performed with the atomic beam polarimeter of the HERMES polarized deuterium target and the results have been used to optimize the sextupole system of the polarimeter.

An atomic beam polarimeter for measurement of the hyperfine population numbers and the absolute polarization of thermal atomic hydrogen (H) and deuterium (D) beams is described. The principle of measurement and the method of calibration are given. The polarimeter measures the 4 (6) relative hyperfine population numbers of a thermal H (D) beam in the region of 10 13 atoms s −1 to an absolute error of less than 0.01. The polarimeter has been in continuous operation with the internal polarized hydrogen and deuterium gas target used in the HERMES experiment at DESY since 1996.

A single-spin asymmetry in the azimuthal distribution of neutral pions relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off longitudinally polarized protons. The analysing power in the sin(phi) moment of the cross section is 0.019 +/- 0.007(stat.) +/- 0.003(syst.). This result is compared to single-spin asymmetries for charged pion production measured in the same kinematic range. The pi^0 asymmetry is of the same size as the pi^+ asymmetry and shows a similar dependence on the relevant kinematic variables. The asymmetry is described by a phenomenological calculation based on a fragmentation function that represents sensitivity to the transverse polarization of the struck quark., Comment: 4 pages, 1 figure, replaced to correct eprint author field, 2nd replacement to correct figure; upper limit of model predictions are corrected. No correction to data or conclusions

The nuclear polarization of H(2) molecules formed by recombination of polarized H atoms on a Cu surface was measured as a function of external magnetic field and of temperature of the surface. The proton polarization of the molecules was determined by scattering of a longitudinally polarized 203-MeV proton beam in the Indiana University Cyclotron Facility storage ring. The nuclear polarization of the molecules, relative to the polarization of the atoms before recombination, increased from near zero in a weak magnetic field to 0.42 +/- 0.02 in a 0.66 T field. A simple model of the relaxation accounts quantitatively for the observations.

A single-spin asymmetry in the distribution of exclusively produced pi^+ mesons azimuthally around the virtual photon direction relative to the lepton scattering plane has been measured for the first time in deep-inelastic scattering of positrons off longitudinally polarized protons. Integrated over the experimental acceptance, the sin \phi moment of the polarization asymmetry of the cross section is measured to be -0.18 +/- 0.05 (stat.) +/- 0.02 (syst.). The asymmetry is also studied as a function of the relevant kinematic variables, and its magnitude is found to grow with decreasing x and increasing -t and vanish at t -> t_min (where x is the Bjorken scaling variable and t is the squared four-momentum transferred to the nucleon)., Comment: PLB accepted version, 6 pages, 4 figures, LaTex (revtex4), corrected typo

The beam-spin asymmetry in hard electroproduction of photons has been measured for the first time. The data have been accumulated by the HERMES experiment at DESY using the HERA 27.6 GeV longitudinally polarized positron beam and an unpolarized hydrogen gas target. The asymmetry in the azimuthal distribution of the produced photons in the angle phi relative to the lepton scattering plane was determined with respect to the helicity state of the incoming positron beam. The beam-spin analyzing power in the sin(phi) moment was measured to be -0.23 +/- 0.04(stat) +/- 0.03(syst) in the missing-mass range below 1.7 GeV. The observed asymmetry is attributed to the interference of the Bethe-Heitler and deeply-virtual Compton scattering processes., Comment: 6 pages, 5 figures, revised experimental description

The spin correlation coefficent combinations A{sub xx}+A{sub yy} and A{sub xx}-A{sub yy}, the spin correlation coefficients A{sub xz} and A{sub zz}, and the analyzing power were measured for p(vector sign)p(vector sign){yields}d{pi}{sup +} between center-of-mass angles 25 degree sign {

A polarized proton beam with a large longitudinal polarization component of $0.545\ifmmode\pm\else\textpm\fi{}0.005$ (96% of the total polarization) was prepared in a storage ring (IUCF--Cooler). This was achieved by means of spin precession solenoids in two of the six straight sections of the ring. A polarized hydrogen storage cell target internal to the ring was used to measure the longitudinal spin correlation coefficient ${A}_{\mathrm{zz}}$ in $\mathrm{pp}$ elastic scattering over the laboratory angular range $5.5\ifmmode^\circ\else\textdegree\fi{}$--$43.5\ifmmode^\circ\else\textdegree\fi{} ({\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=11.5\ifmmode^\circ\else\textdegree\fi{}$--$90\ifmmode^\circ\else\textdegree\fi{})$ with statistical errors of typically 0.025. The absolute normalization was determined to an accuracy of 2.0% by use of the identity ${A}_{\mathrm{yy}}\ensuremath{-}{A}_{\mathrm{xx}}\ensuremath{-}{A}_{\mathrm{zz}}\ensuremath{\equiv}1$ at ${\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=90\ifmmode^\circ\else\textdegree\fi{}.$ The identity also allows a reduction of the scale factor uncertainty of the previously published analyzing powers and spin correlation coefficients. The results are compared to recent $\mathrm{pp}$ partial wave analyses and $\mathrm{NN}$ potential models.

A planned experiment to measure the nuclear polarization of H2 molecules formed by recombination of polarized H atoms is described. Polarization will be measured with a longitudinally polarized 200 MeV proton beam and a longitudinally polarized storage cell gas target at the IUCF cooler ring.

The dependence on Q^2 (the negative square of the 4-momentum of the exchanged virtual photon) of the generalised Gerasimov-Drell-Hearn integral for the proton has been measured in the range 1.2 GeV^2 < Q^2 < 12 GeV^2 by scattering longitudinally polarised positrons on a longitudinally polarised hydrogen gas target. The contributions of the nucleon-resonance and deep-inelastic regions to this integral have been evaluated separately. The latter has been found to dominate for Q^2 > 3 GeV^2, while both contributions are important at low Q^2. The total integral shows no significant deviation from a 1/Q^2 behaviour in the measured Q^2 range, and thus no sign of large effects due to either nucleon-resonance excitations or non-leading twist., 9 pages, 3 figures, 1 table

A new facility for particle physics has been installed at the spallation source SINQ. An experimental area has been constructed for a series of experiments fed by a high intensity, polarized cold neutron beam. The physics program for this new facility will focus on free neutron decay studies addressing mainly the questions of fundamental symmetries (time reversal and parity) in the weak interactions.

To aid fundamental studies on the polarization of electrons in beta decay, measurements were made of the spin dependence in the scattering of 14 MeV electrons from Pb as a function of scattering angle and foil thickness. The experiment made use of a beam of polarized electrons from a strained GaAsP cathode. A simple theoretical model based on plural scattering explains the observed dependence of the analyzing power on foil thickness. The results extrapolated to infinitely thin targets are in excellent agreement with theory if the finite nuclear size is taken into account.

Polarization effects were studied in the elastic scattering of 14 MeV electrons from lead nuclei. The left/right asymmetry was measured at eight scattering angles between 126° and 172°. For each angle the effective analyzing power for scattering foils of various thicknesses was measured. The determined analyzing powers for thin targets are in good agreement with the Mott theory. Effects of the finite size of the lead nuclei are observed. This is the first polarization test of the Mott scattering theory for electrons with energies above 1 MeV.

The virtual photon absorption cross section differences [sigma_1/2-sigma_3/2] for the proton and neutron have been determined from measurements of polarised cross section asymmetries in deep inelastic scattering of 27.5 GeV longitudinally polarised positrons from polarised 1H and 3He internal gas targets. The data were collected in the region above the nucleon resonances in the kinematic range nu < 23.5 GeV and 0.8 GeV**2 < Q**2 < 12 GeV**2. For the proton the contribution to the generalised Gerasimov-Drell-Hearn integral was found to be substantial and must be included for an accurate determination of the full integral. Furthermore the data are consistent with a QCD next-to-leading order fit based on previous deep inelastic scattering data. Therefore higher twist effects do not appear significant., 6 pages, 3 figures, 1 table, revtex

The flavor asymmetry of the light quark sea of the nucleon is determined in the kinematic range 0.02, Comment: 7 Pages, 2 figures, RevTeX format; slight revision in text, small change in extraction of dbar-ubar and comparison with a high q2 parameterization

Theoretical and experimental work seeking to understand the phenomenon of parity violation within the nucleon-nucleon system is reviewed.

Results of the first two experiments that use polarized hydrogen targets in proton storage rings are discussed. Both experiments used storage cell targets, i.e., long, narrow, windowless target cells into which polarized hydrogen atoms from an atomic‐beam source are injected and through which the circulating beam passes. In the first experiment, carried out at the test storage ring of the Max Planck Institut in Heidelberg, a 27 MeV beam of alpha particles was passed through the target cell to measure the target polarization and the target thickness, and to investigate possible problems arising from background and from target depolarization by the beam. The target was used for a test of principle of the spin filter (spin‐selective attenuation) as a means to polarize the circulating beam. The second experiment, currently in progress at the IUCF proton storage ring, has demonstrated the feasibility of spin correlation experiments at 200 MeV by detecting recoil protons in coincidence with scattered protons at...

A polarized internal H gas storage cell target has been successfully operated in the IUCF cooler ring. A target thickness for atomic hydrogen has been measured to be 3.5±0.3×1013/cm2 in a single spin state. Target polarization (0.75±0.01) showed no sign of deterioration after two weeks of operation with an average beam current of 100 μA. Detection of p‐p elastic events at 200 MeV bombarding energy has been demonstrated by use of coincidences between silicon detectors near the beam and a forward detector array. This target is presently being used to measure p‐p elastic scattering spin correlation coefficients at 200 MeV.

A storage cell target of polarized hydrogen gas was installed in a storage ring to study the target characteristics (nuclear polarization, target thickness, radiation resistance). The density of the target gas was enhanced by cooling the cell. Using a weak transverse guide field (5 G), the nuclear polarization of the target was measured to be 0.80±0.02 when atoms in a single hyperfine state were selected. The areal density of the target under these conditions was 5.5⋅1013 H↘/cm2 (T=115 K), while for two spin states (applicable to experiments in high energy rings, where a strong magnetic field can be applied to the target) the target thickness was found to be 8.2⋅1013 H↘/cm2.

The first experiment to be performed an the internal target facility of NIKHEF-K will be a study of eleclron-induced quasi-elastic proton knock-out from tensor-polarized deuterium. Here, we present the first results from the experimental tests as well as the results of a Monte Carlo simulation, which show the feasibility of the proposed experiment, even at modest luminosities.

Polarized gas targets of atomic hydrogen and deuterium have significant advantages over conventional polarized targets, e.g. chemical and isotopic purity, large polarization including deuteron tensor polarization, absence of strong magnetic fields, rapid polarization reversal. While in principle the beam of polarized atoms from an atomic beam source (Stern-Gerlach spin separation) can be used as a polarized target, the target thickness achieved is too small for most applications. We propose to increase the target thickness by injecting the polarized atoms into a storage cell. Provided the atoms survive several hundred wall collisions without losing their polarization, it will be possible to achieve a target thickness of 10{sup 13} to 10{sup 14} atoms/cm{sup 2} by injection of polarized atoms from an atomic-beam source into suitable cells. Such targets are very attractive as internal targets in storage rings.

A storage cell has been constructed for use as an internal target at the IUCF electron‐cooled storage ring (Cooler). We report on nuclear polarization measurements of hydrogen, produced by an atomic beam source (ABS), in this storage cell. The results indicate a target polarization in excess of 0.70 for atoms in a single spin state.

Physical review letters 71(9), 1379 - 1382 (1993). doi:10.1103/PhysRevLett.71.1379, A feasibility test of a new method to polarize beams of strongly interacting charged particles circulating in a storage ring is described. The stored particles, here protons, pass through a polarized hydrogen gas target (thickness 6×1013 H/cm2) in the ring some 1010 times and become partially polarized because one spin state is attenuated faster than the other. The polarization buildup is clearly demonstrated in the present experiment., Published by APS, College Park, Md.

To provide an accurately calibrated polarization analyzer, the analyzing power for elastic scattering of protons from natural carbon at ${\mathit{E}}_{\mathrm{lab}}$=50.24 MeV and ${\mathrm{\ensuremath{\theta}}}_{\mathrm{lab}}$=50.0\ifmmode^\circ\else\textdegree\fi{} was measured by scattering protons of very high and precisely known polarization (0.9965\ifmmode\pm\else\textpm\fi{}0.0007) from a graphite target. The result of the calibration is A=0.9277\ifmmode\pm\else\textpm\fi{}0.0036, where the error is the quadratic sum of the statistical error \ifmmode\pm\else\textpm\fi{}0.0033 and systematic uncertainties which total \ifmmode\pm\else\textpm\fi{}0.0016.

The transverse polarization in a plane perpendicular to the nuclear spin has been measured for electrons emitted in the beta decay of polarized {sup 8}Li nuclei. The amplitude {ital R} of the time-reversal violating triple correlation between nuclear spin, momentum, and spin of the electron has been determined. Our result, {ital R}=0.004{plus minus}0.014, is consistent with time-reversal invariance and provides a first direct limit on the imaginary charged weak tensor interaction {minus}0.03{lt}Im({ital C}{sub {ital T}}+{ital C}{sub {ital T}}{sup {prime}})/{ital C}{sub {ital A}}{lt}0.05.

The exploration of spin degrees of freedom in nuclear and high-energy interactions requires the use of spin-polarized projectiles and/or spin-polarized targets. During the last two decades, the use of external beams from cyclotrons has to a large extent been supplanted by use of circulating beams stored in storage rings. In these experiments, the circulating particles pass millions of times through targets internal to the ring. Thus the targets need to be very thin to avoid beam loss by scattering out of the acceptance aperture of the ring.

The transverse polarization of the electrons emitted in the decay of polarized 8Li has been measured. The magnitude R of the T‐odd correlation J↘⋅(p↘e×s↘e) between the directions of the nuclear spin J↘, the momentum p↘e, and the spin s↘e of the electrons has been determined. The present result R=0.004±0.014 is consistent with time reversal invariance.

The time reversal violating R-coefficient has been measured for the beta decay of 8U. The result, R = −0.024 ± 0.044, is the most accurate limit on this coefficient in nuclear beta decay to date.

We report here a measurement of the analyzing power Ay in 185 MeV elastic proton-proton (pp) scattering at forward angles (2.5°–10.5° in the laboratory). In this angular range the Coulomb and nuclear amplitudes are of similar magnitude and measurements of polarization observables allow separation of the real and imaginary components of the nuclear amplitudes by their interference with the known Coulomb amplitude.[1] Precise measurements at such small angles can be difficult due to the presence of beam halo or scattering from target materials other than hydrogen. In the present experiment we have used both a windowless gas jet target and coincident detection of the low energy proton at large angles to eliminate these backgrounds.

This paper describes recent wall depolarization studies, in which the degree of polarization of hydrogen atoms in a storage cell was measured for different wall coatings as a function of wall temperature. For the cells tested, the average number of wall collisions of atoms in the cell varied between 40 and 380. It is found that cells coated with a thin film of fluorinated polymers tolerate 380 wall collisions for wall temperatures between 120K and 300K without significant loss in polarization.

The Time Reversal Violating R-parameter in the decay of 8Li has been measured with the result R = -0.024 ± 0.044. This quantity is sensitive to imaginary parts of the tensor coupling constants that might be present in the non-standard models of the weak interaction.

This review describes the development and present performance of nuclear polarized gas targets in nuclear or particle physics experiments. After a brief account of the various development steps, the design principles for the relevant light nucleon targets, hydrogen, deuterium and 3He, for storage rings, are discussed. Most of these targets make use of so-called storage cells in order to enhance the target thickness. The performance of targets used in medium and high-energy ion and electron storage rings is reviewed. Finally, future trends and possible improvements are discussed.

Spin transfer in deep-inelastic Lambda electroproduction has been studied with the HERMES detector using the 27.6 GeV polarized positron beam in the HERA storage ring. For an average fractional energy transfer = 0.45, the longitudinal spin transfer from the virtual photon to the Lambda has been extracted. The spin transfer along the Lambda momentum direction is found to be 0.11 +/- 0.17 (stat) +/- 0.03 (sys); similar values are found for other possible choices for the longitudinal spin direction of the Lambda. This result is the most precise value obtained to date from deep-inelastic scattering with charged lepton beams, and is sensitive to polarized up quark fragmentation to hyperon states. The experimental result is found to be in general agreement with various models of the Lambda spin content, and is consistent with the assumption of helicity conservation in the fragmentation process., Comment: 8 pages, 3 figures; new version has an expanded discussion and small format changes

Parity nonconservation in $p\ensuremath{-}p$ scattering has been studied by comparing the cross sections ${\ensuremath{\sigma}}^{+}$, and ${\ensuremath{\sigma}}^{\ensuremath{-}}$ for longitudinally polarized 45-MeV protons of positive and negative helicity. The longitudinal analyzing power is found to be ${A}_{z}=\ensuremath{-}(3.2\ifmmode\pm\else\textpm\fi{}1.1)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$. The quoted uncertainty includes the statistical error, the uncertainties of corrections applied, and estimates of systematic effects.

Existing phase shift solutions for p- 4 He elastic scattering have been tested experimentally. The angle where the proton analyzing power crosses zero has been measured at several energies between 3.5 and 8.9 MeV. In a separate experiment, the ratio of the cross sections at 169° and 104° c.m. has been measured with an accuracy of ± 1.0 % for energies between 2.2 and 5.9 MeV. Of the four energy-dependent phase shift solutions recently reported in the literature, two show large discrepancies with the measurements.

In the study of parity violation by the scattering of longitudinally polarized spin 1 2 particles, systematic errors arise from the presence of small polarization components perpendicular to the beam. A quantitative treatment of these errors is presented. It is shown that non-uniform polarization distributions over the beam profile give sizeable effects even if the average transverse polarization vanishes. Methods are presented which permit accurate correction of the parity measurements for the presence of transverse polarization components. It is shown that the necessary information can be obtained by measuring four suitably chosen one-dimensional intensity and polarization distributions within the beam. Finally, possible origins of the non-uniform polarization distributions are outlined.

A polarimeter which simultaneously measures the vector and tensor moments Re(i t 11 ), t 20 , Re( t 21 ) and Re( t 22 ) of a 5–12 MeV deuteron beam is described. The polarimeter uses the 3 He(d, p) 4 He reaction as the polarization analyzer. The polarimeter analyzing powers T 20 and T 22 are calibrated against the 16 O(d, α 1 ) 14 N reaction and the i T 11 and analyzing powers are calibrated against the 16 O(d, α 3 ) 14 N reaction. With the present calibration, the beam polarization moments may be measured to 2% for beam energies from 5–10 MeV.

Vector analyzing powers, tensor analyzing powers, and relative differential cross sections have been measured for the /sup 2/H(d-arrow-right,..gamma..) /sup 4/He reaction at an incident energy of 10 MeV. Multipole decomposition and partial-wave analysis reveal that about 15% of the cross section involves processes in which the tensor force plays a role, either in the entrance or exit channel. Contrary to earlier claims, the reaction cannot be used to determine the D-state admixture in the /sup 4/He wave function unless the D state of the deuteron and other tensor-force effects in the entrance channel are taken into account.

The cross section, vector analyzing power, and proton polarization have been measured for the ln = 0 reaction 116Sn(d, p)117Sn(g.s.) at 8.22 MeV. In addition, cross section and analyzing power data have been obtained at 8.22 MeV for 116 Sn ( d , d ) 116 Sn and for 116Sn(d, p)117Sn leading to excited states of 117Sn at 0.159, 0.317, 1.020, 1.179, 1.308 and 1.497 MeV. The cross section and analyzing power for 117 Sn ( p , p ) Sn and for 117 Sn ( p , d ) 116 Sn leading to the 1.294 MeV state of 116Sn have also been measured at 12.91 MeV. The data for 116Sn(d, p)117Sn(g.s.) have been used to separate the contributions to the analyzing power arising from spin-dependent forces in the proton and deuteron channels. A similar analysis is presented for an l n = 0 90 Zr ( d, p ) 91 Zr transition at 11 MeV. Optical-model analyses have been performed for the elastic scattering data. The reaction data have been compared with distorted-wave calculations in order to investigate the validity of various deuteron potentials, as well as to extract spectroscopic information.

Angular distributions of the vector analyzing power and the absolute cross section were measured for ( d , p ) reactions on the odd- A nuclei 53 Cr and 57 Fe at a deuteron energy of 10 MeV and on 117 Sn and 119 Sn at 12 MeV. It is shown that the separate cross section contributions for the different allowed total angular momenta j n of the captured neutron can be determined from the measurements. For transitions which are dominated by a single value of j n , the measurements are compared with distorted-wave Born approximation calculations. The energies of the 2 p 3 2 and 2 p 1 2 neutron single-particle states in 54 Cr and 58 Fe were determined, and the strength of the nuclear spin-orbit interaction was calculated. The vector analyzing power and the cross section were also measured for deuteron elastic scattering from each target nucleus in order to determine optical-model parameters for the DWBA calculations.

Some observations which pertain to the interaction of ice and lake water in a high alpine environment and which were made in recent years in connection with hydroelectric projects and flood protection work are presented. In 1966, when the thin flat snout of Griesgletscher (Walliser Alpen) became submerged during the first filling of a newly constructed reservoir, waves of only very small amplitude were generated by the calving of a bout 150000 m3 of ice because most of the energy was dissipated by local turbulence. Far more spectacular waves have been experienced near steep ice cliffs in connection with work for flood control. For the design of an air bubbler system, air and water temperatures were measured in winter 1974–75 at Grimselsee, one of the largest reservoirs in the Bernese Alps. These measurements showed that the warmest water at the bottom of the lake was drained away during winter for the production of electricity. A strong temperature invenion forms in the air a bove the water behind the dam, as the lake level is lowered by several tens of metres.

The polarization in proton-proton scattering at an incident energy of 10.0±0.05 MeV has been measured at seven angles with an accuracy of ±0.02%. A gaseous hydrogen target (1–2 atm) was bombarded with polarized protons. The sign of the beam polarization was reversed with a spin-precession solenoid between the ion source and the accelerator. The beam polarization (75–80%) was monitored continuously with a p-α polarimeter which was calibrated in terms of a precision p-α measurement of Ohlsen, et.al.1).

The tensor analyzing powers T 20 , T 21 and T 22 have been measured at 13 MeV bombarding energy for three transitions in 64 Zn(d, t) 63 Zn and for the g.s. transition in 64 Zn(d, 3 He) 63 Cu. The measurements are compared to DWBA calculations which include the D-state component in the internal wave function of the outgoing tritons and 3 He, using the local-energy approximation. The parameter D 2 , which provides a measure of the D-state amplitude, is found to be larger for 3 He than for the triton by a factor 1.27±0.13.

Angular distributions of the cross section and vector analyzing power were measured for elastic scattering of 9, 11 and 13 MeV deuterons from 27Al, Si, 46Ti, 48Ti, 53Cr, 68Zn, 90Zr and 120Sn. The results were analyzed with the optical model. The analysis also included results from similar previous experiments on 18 nuclides for deuteron energies between 5 and 12.3 MeV. Good agreement with most of the measurements was obtained by adjusting only the parameters of the absorptive part of the potential from one nucleus to the next. All other parameters were held constant, except for the real potential depth which was assumed to depend on Z/A 1 3 . The volume integral of the imaginary potential seems to be correlated with the deformation parameter.

The vector analyzing power and differential cross section have been measured at a deuteron energy of 12.0 MeV for 118 Sn ( d , t ) transitions to six states of 117Sn (Ex = 0.0, 0.16, 0.31, 0.71, 1.02 and 1.18 MeV), for 98 Mo ( d , t ) transitions to eight states of 97Mo (Ex = 0.0, 0.68, 0.72, 0.89, 1.12, 1.28, 2.39 and 2.52 MeV), and for 118 Sn ( d , d ) and 98 Mo ( d , d ) . Deuteron optical model potentials were obtained from analysis of the elastic scattering measurements, and were used in a DWBA analysis of the ( d , t ) results. Comparison of the measurements and DWBA predictions for σ(θ) and for iT11(θ) allows unambiguous determination of tln and jn for all 118Sn(d, t) and most 98Mo(d, t) transitions. Differences in the triton energy relative to the Coulomb barrier cause marked qualitative differences in the measured cross sections and analyzing powers between 118 Sn ( d , t ) and 98 Mo ( d , t ) transitions of the same ln and jn.

Thermal polarized 6,7Li atoms, produced by an atomic-beam source, were bombarded by a beam of fast Cs0 atoms in order to form polarized negative 6,7Li ions for injection into a tandem accelerator. A beam intensity of 0.28 μA has been achieved. The measured tensor polarization of the 6Li beam was Pζζ = 0.88. The beam intensity agrees well with the value calculated using the known charge exchange cross section.

The vector analyzing power iT 11 ( θ ) and absolute cross section σ(θ) for 64 Zn ( d , t ) 63 Zn and 64 Zn ( d , 3 He ) 63 Cu have been measured at a deuteron energy of 13.0 MeV. Transitions to three states of 63 Zn ( E x = 0.0, 0.19 and 0.25 MeV), and to the g.s. of 63 Cu were studied. Measurements of σ(θ) and iT 11 ( θ ) were also made for deuteron elastic scattering from 64 Zn. The analysis of the elastic scattering data provided deuteron optical-model parameters that were used in DWBA calculations. Comparison of the data with DWBA predictions permits the unambiguous determination of J π for the four transitions studied.