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Experimental information on fragment emissions is important in understanding the dynamics of nuclear collisions and in the development of transport model simulating heavy-ion collisions. The composition of complex fragments emitted in the heavy-ion collisions can be explained by statistical models, which assume that thermal equilibrium is achieved at collision energies below 100 MeV/u. Our new experimental data together with theoretical analyses for light particles from Sn+Sn collisions at 270 MeV/u, suggest that the hypothesis of thermal equilibrium breaks down for particles emitted with high transfer momentum. To inspect the system's properties in such limit, the scaling features of the yield ratios of particles from two systems, a neutron-rich system of ${}^{132}\mathrm{Sn}+{}^{124}\mathrm{Sn}$ and a nearly symmetric system of ${}^{108}\mathrm{Sn}+{}^{112}\mathrm{Sn}$, are examined in the framework of the statistical multifragmentation model and the antisymmetrized molecular dynamics model. The isoscaling from low energy particles agree with both models. However the observed breakdown of isoscaling for particles with high transverse momentum cannot be explained by the antisymmetrized molecular dynamics model.

The new isotope ^{39}Na, the most neutron-rich sodium nucleus observed so far, was discovered at the RIKEN Nishina Center Radioactive Isotope Beam Factory using the projectile fragmentation of an intense ^{48}Ca beam at 345 MeV/nucleon on a beryllium target. Projectile fragments were separated and identified in flight with the large-acceptance two-stage separator BigRIPS. Nine ^{39}Na events have been unambiguously observed in this work and clearly establish the particle stability of ^{39}Na. Furthermore, the lack of observation of ^{35,36}Ne isotopes in this experiment significantly improves the overall confidence that ^{34}Ne is the neutron dripline nucleus of neon. These results provide new key information to understand nuclear binding and nuclear structure under extremely neutron-rich conditions. The newly established stability of ^{39}Na has a significant impact on nuclear models and theories predicting the neutron dripline and also provides a key to understanding the nuclear shell property of ^{39}Na at the neutron number N=28, which is normally a magic number.

Aims Globular glial tauopathy (GGT) is a new category within the 4-repeat tauopathies that is characterised neuropathologically by tau-positive globular glial inclusions (GGIs), namely, globular oligodendrocytic and astrocytic inclusions (GOIs and GAIs). Occurrence of tau-positive neuronal cytoplasmic inclusions (NCIs) is also a feature. GGT is classified into three pathological subtypes (Types I, II and III). We studied the tau pathology in 6 cases of GGT (Type II, n = 3; Type III, n = 3), with special reference to GAIs and NCIs. Methods Neuropathological examinations were conducted, along with immunohistochemistry, morphometry and three-dimensional imaging, and biochemical and genetic analysis of tau. Results The cortical GAIs in Type II and those in Type III were distinguishable from each other. In the motor cortex, GAIs were much more numerous in Type III than in Type II. Prominent occurrence of perikaryal globular structures was a feature of GAIs in Type III. By contrast, prominent occurrence of radiating process-like structures was a feature of GAIs in Type II. Overall, the GAIs were significantly smaller in Type III than in Type II. NCIs were divisible into three subgroups in terms of shape: diffuse granular, thick cord-like, and round/horseshoe-shaped structures. In all cases, NCIs were a feature of the upper and lower motor neurons. Interestingly, the round/horseshoe-shaped NCIs were observed only in Type III cases. Conclusions These findings, which characterised GAIs and NCIs, indicated that Type II and Type III constitute two distinct pathological subtypes, and also further strengthen the concept of GGT as a distinct entity.

Excited states in 63,65,67Mn were studied via in-beam γ-ray spectroscopy following knockout reactions from 68Fe. Similar level schemes, consisting of the 11/2−, 9/2−, 7/2− and 5/2 g.s.− level sequence, connected by I→I−1 transitions, were established, the first time for 65,67Mn. Their level structures show features consistent with strongly-coupled rotational bands with K=5/2 . State-of-the-art shell-model calculations with the modified LNPS effective interaction reproduce the observed levels remarkably well and suggest the dominance of 4-particle-4-hole neutron configurations for all the states. The data on the low-lying excited states of odd-mass 53−67Mn provide a textbook example of nuclear structure evolution from weak coupling through decoupling to strong coupling along a single isotopic chain on the n-rich side of the β stability line. These results help to deepen our understanding of the N=40 “island of inversion”.

Spectroscopic factors of neutron-hole and proton-hole states in ^{131}Sn and ^{131}In, respectively, were measured using one-nucleon removal reactions from doubly magic ^{132}Sn at relativistic energies. For ^{131}In, a 2910(50)-keV γ ray was observed for the first time and tentatively assigned to a decay from a 5/2^{-} state at 3275(50) keV to the known 1/2^{-} level at 365 keV. The spectroscopic factors determined for this new excited state and three other single-hole states provide first evidence for a strong fragmentation of single-hole strength in ^{131}Sn and ^{131}In. The experimental results are compared to theoretical calculations based on the relativistic particle-vibration coupling model and to experimental information for single-hole states in the stable doubly magic nucleus ^{208}Pb.

We have combined the low-energy neutron detector WINDS (Wide-angle Inverse-kinematics Neutron Detectors for SHARAQ) and the SAMURAI spectrometer at RIKEN Nishina Center RI Beam Factory (RIBF) in order to perform ( p , n ) reactions in inverse kinematics for unstable nuclei in the mass region around A ∼ 100 . In this setup, WINDS is used for detecting recoil neutrons and the SAMURAI spectrometer is used for tagging decay channel of heavy residue. The first experiment by using the setup was performed to study Gamow–Teller transitions from 132 Sn in April 2014. The atomic number Z and mass-to-charge ratio A / Q of the beam residues were determined from the measurements of time of flight, magnetic rigidity and energy loss. The obtained A / Q and Z resolutions were σ A / Q = 0.14 % and σ Z = 0.22 , respectively. Furthermore, owing to the large momentum acceptance ( 50 % ) of SAMURAI, the beam residues associated with the γ , 1n and 2n decay channel were measured in the same magnetic field setting. The kinematic loci of the measured recoil neutron energy and laboratory angle are clearly seen. It shows that the excitation energy up to about 20 MeV can be reconstructed.

The key parameter to discuss the possibility of the pion condensation in nuclear matter, i.e., the so-called Landau-Migdal parameter g^{'}, was extracted by measuring the double-differential cross sections for the (p,n) reaction at 216 MeV/u on a neutron-rich doubly magic unstable nucleus, ^{132}Sn with the quality comparable to data taken with stable nuclei. The extracted strengths for Gamow-Teller (GT) transitions from ^{132}Sn leading to ^{132}Sb exhibit the GT giant resonance (GTR) at the excitation energy of 16.3±0.4(stat)±0.4(syst) MeV with the width of Γ=4.7±0.8 MeV. The integrated GT strength up to E_{x}=25 MeV is S_{GT}^{-}=53±5(stat)_{-10}^{+11}(syst), corresponding to 56% of Ikeda's sum rule of 3(N-Z)=96. The present result accurately constrains the Landau-Migdal parameter as g^{'}=0.68±0.07, thanks to the high sensitivity of the GTR energy to g^{'}. In combination with previous studies on the GTR for ^{90}Zr and ^{208}Pb, the result of this work shows the constancy of this parameter in the nuclear chart region with (N-Z)/A=0.11 to 0.24 and A=90 to 208.

This corrects the article DOI: 10.1103/PhysRevLett.119.192501.

The discovery of the important neutron-rich nucleus _{20}^{60}Ca_{40} and seven others near the limits of nuclear stability is reported from the fragmentation of a 345 MeV/u ^{70}Zn projectile beam on ^{9}Be targets at the radioactive ion-beam factory of the RIKEN Nishina Center. The produced fragments were analyzed and unambiguously identified using the BigRIPS two-stage in-flight separator. The eight new neutron-rich nuclei discovered, ^{47}P, ^{49}S, ^{52}Cl, ^{54}Ar, ^{57}K, ^{59,60}Ca, and ^{62}Sc, are the most neutron-rich isotopes of the respective elements. In addition, one event consistent with ^{59}K was registered. The results are compared with the drip lines predicted by a variety of mass models and it is found that the models in best agreement with the observed limits of existence in the explored region tend to predict the even-mass Ca isotopes to be bound out to at least ^{70}Ca.

We have developed a simple one-dimensional scintillating fiber detector (SFD) for momentum tagging high-energy (a few hundred MeV per u) and high-intensity ( ∼ 10 6 particles per second, pps) beams of light ( Z ≤ 10 ) ions in the momentum-dispersive focal plane of a fragment separator. This SFD consists of 60 rows of scintillating fibers that have 2 mm square cross-sections. The detection efficiency is constant for beam intensities between 103 and 106 pps and a position detection efficiency of 100% is achieved by injecting ions obliquely. The position resolution is less than 1 mm (rms). In addition, the SFD is demonstrated to be effective for identifying particles in cocktail beams. These results show that the application of scintillating fibers is found to be one of the most suitable methods to tag the light radioactive ion beams.

We have developed a large, thin solid hydrogen target (SHT) that is 30 mm in diameter and 1 mm thick for elastic scattering of protons from unstable nuclei. By using para-H 2 that has a high thermal conductivity at low temperatures, we could prevent sublimation at the target center due to radiation from the higher temperature surroundings. The uniform SHT was used during long-term scattering experiments and it maintained its shape and thickness.

A Gamow–Teller (GT) transition from the drip-line nucleus 14Be to 14B was studied via the ( p , n ) reaction in inverse kinematics using a secondary 14Be beam at 69 MeV/nucleon. The invariant mass method is employed to reconstruct the energy spectrum. A peak is observed at an excitation energy of 1.27(2) MeV in 14B, together with bumps at 2.08 and 4.06(5) MeV. The observed forward peaking of the state at 1.27 MeV and a good description for the differential cross section, obtained with a DWBA calculation provide support for the 1 + assignment to this state. By extrapolating the cross section to zero momentum transfer the GT-transition strength is deduced. The value is found to compare well with that reported in a β-delayed neutron emission study.

An experimental study for the unbound nucleus 13Be has been performed by means of the invariant mass method via the one-neutron removal reaction H 1 ( Be 14 , Be 12 + n ) . A resonance has been observed at 0.51(1) MeV in the relative energy ( E rel ) spectrum of the Be 12 + n system. The transverse momentum distribution of the Be 12 + n system as well as the resonance width of 0.45(3) MeV gives evidence for the p-wave nature of the resonance. A d-wave resonance has also been observed at 2.39(5) MeV in the E rel spectrum. The observation of the low-lying p-wave resonance indicates the disappearance of the N = 8 magicity in the vicinity of the neutron drip line region.

Recoiled proton tagged knockout reaction experiments were carried-out for He-8 at 82.5 MeV/u in RIKEN and for He-6 at 65 MeV/u in Lanzhou. The very preliminary results for the distinguish of the reaction mechanism are presented and compared to the kinematics calculation.

Proton knockout reactions on carbon isotopes p( 9–16 C,2p) 8–15 B at 250 MeV/A were performed for systematic information on weakly- to strongly-bound 1p valence protons and deeply-bound 1s inner-shell protons. Various information such as the s-hole distributions, excitation energy of the s-hole states, momentum widths for 1s and 1p orbits, and relative (p,2p) yields are obtained.

The neutron-rich carbon isotopes 19,17C have been investigated via proton inelastic scattering on a liquid hydrogen target at 70 MeV/nucleon. The invariant mass method in inverse kinematics was employed to reconstruct the energy spectrum, in which fast neutrons and charged fragments were detected in coincidence using a neutron hodoscope and a dipole magnet system. A peak has been observed with an excitation energy of 1.46(10) MeV in 19C, while three peaks with energies of 2.20(3), 3.05(3), and 6.13(9) MeV have been observed in 17C. Deduced cross sections are compared with microscopic DWBA calculations based on p-sd shell model wave functions and modern nucleon-nucleus optical potentials. Jpi assignments are made for the four observed states as well as the ground states of both nuclei., 20 pages

Single-phase rare-earth gallium garnets were obtained by the reaction of stoichiometric mixtures of gallium acetylacetonate and rare-earth (Nd-Lu) acetates in 1,4-butanediol at 300°C (glycothermal reaction). Particles of gadolinium gallium garnet (GGG) and other gallium garnets with rare-earth elements larger than Gd were spherical with diameters of 0.5-2 μm, while particles of garnets with smaller rare-earth ions (Tb-Lu and Y) were much smaller (100-300 nm) with particle size distributed in a quite narrow range. TEM observation revealed that each particle was essentially a single crystal grown from one nucleus, but that defects frequently occurred during the crystal growth. Cerium and praseodymium gallium garnets were also formed when the reaction was carried out in the presence of GGG seed crystals. Hydrothermal reactions of the same starting materials under identical conditions yielded mixtures of gamma-Ga2O3 and the garnet phase.

There are various angiographic and runoff scoring systems for evaluating stenosis and arterial occlusion in patients with peripheral artery disease (PAD). The report from the BASIL trial revealed that the Bollinger scoring system, originally designed to classify intra-arterial digital subtraction angiography (IADSA), was sensitive to differences in PAD. The purpose of the present study was to evaluate the application of the Bollinger scoring system to a 64-low multidetector computed tomography (MDCT) in PAD patients.Patients with PAD who underwent both a 64-MDCT and DSA within a 4-year period were enrolled in the study. Two observers analyzed the MDCT and DSA images for each patient. We divided the arterial tree from the common iliac artery to the plantar arch into 16 segments and scored 0-15 points for each segment as reported by Bollinger, according to the severity and extent of disease. We analyzed the reliability of differences in scores between the DSA and MDCT by the intraclass correlation coefficients (ICCs).We reviewed 100 consecutive patients (127 limbs) and assessed a total of 1929 segments. The Bollinger score of the 2 tests were same in 39.6% of all segments. The difference between the 2 tests were within 2 points in 77.3% of the above-knee segments (70.1-91.6% in each segments), 58.8% of the below-knee segments with the exception of plantar arch (42-74%). The ICC values showed relatively good reliability, but in the CFA the ICC values showed poor reliability.The Bollinger scoring method is a useful tool to evaluate peripheral artery angiography with 64-low CT in patients with PAD.

Data related to radioactivity released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident on 15 March 2011 gathered by residents of Miharu, Fukushima Prefecture, and by Tohoku University are presented. These data sets consist of (1) the earliest radiation monitoring by a Geiger counter in the town, (2) ratios of radioactivity between 132Te and 137Cs for a wide area between Fukushima and Tokyo, (3) radiation measurement of soil samples collected from 18 school grounds, and (4) external radiation exposure of 1400 students using OSL badges. By combining and analysing these various data sets, a curve for the cumulative total external exposure as a function of time, with 16 : 00 h on 15 March 2011 being time zero, is obtained. The average cumulative external dosage is estimated to be 10 mSv (σ = 4.2 mSv) over 10 years. In addition, the initiative that the residents of Miharu took in response to the FDNPP accident, which became known as The Misho Project (MP), is documented; in particular, the time at which the municipality instructed the immediate ingestion of iodine tablets by those under the age of 40, 13 : 00 h on 15 March 2011, is assessed.

The deuteron single and double spin-flip probabilities, S1 and S2, have been measured for the 12C(pol{d},pol{d}') reaction at Ed = 270 MeV for an excitation energy range between 4 and 24 MeV and a scattering angular range between Theta_lab = 2.5 and 7.5 deg. The extracted S1 exhibits characteristic values depending on the structure of the excited state. The S2 is close to zero over the measured excitation energy range. The SFP angular distribution data for the 2+ (4.44 MeV) and 1+ (12.71 MeV) states are well described by the microscopic DWIA calculations.

A new approach to study the high momentum component of deuteron D-state wave function by measuring the polarization correlation coefficient, C// [ =1+ 1 4 A yy +A xx + 3 4 C y,y +C x,x ], for the 3 He → ( d → ,p )4He reaction is proposed. The first measurement of C// has been carried out at Ed=270 MeV by using a newly constructed spin-exchange-type polarized 3He target. The obtained value is 0.223±0.044(statistical)±0.037(systematic). DWBA calculations are unable to reproduce the present results. Each component of C// is compared with data for the d+p backward scattering and the deuteron inclusive breakup. A similarity in polarization observables is found among these reactions.

A complete set of polarization transfer coefficients has been measured for quasielastic $(\stackrel{\ensuremath{\rightarrow}}{p},\stackrel{\ensuremath{\rightarrow}}{n})$ reactions on ${}^{2}\mathrm{H},$ ${}^{6}\mathrm{Li},$ ${}^{12}\mathrm{C},$ ${}^{40}\mathrm{Ca},$ and ${}^{208}\mathrm{Pb}$ at a bombarding energy of 346 MeV and a laboratory scattering angle of $22\ifmmode^\circ\else\textdegree\fi{}$ ${(q}_{\mathrm{lab}}\ensuremath{\approx}1.7 {\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}).$ The spin-longitudinal ${R}_{L}$ and spin-transverse ${R}_{T}$ response functions are extracted within a framework of a plane-wave impulse approximation with eikonal and optimal factorization approximations. The theoretically expected enhancement of ${R}_{L}{/R}_{T}$ is not observed. The observed ${R}_{L}$ is consistent with the pionic enhanced ${R}_{L}$ expected by random-phase approximation (RPA) calculations. On the contrary, a large excess of the observed ${R}_{T}$ is found in comparison with ${R}_{T}$ of the quasielastic electron scattering as well as of RPA calculations. This excess masks the effect of pionic correlations in ${R}_{L}{/R}_{T}.$ The theoretical calculations are performed in a distorted-wave impulse approximation with RPA correlations, which indicates that the nuclear absorption effect depends on the spin direction. This spin-direction dependence is responsible in part for the excess of ${R}_{T}.$

The damage evolution in α-Al2O3 single crystals during He+ or H2+ ion irradiation was studied in an electron microscope. The irradiations were performed with 10 keV He+ions at a flux of 1 × 1013 ions/cm2 s and 15 keV H2+ ions at a flux of 1 × 1014 ions/cm2 s over the temperature range of room temperature to 1273 K. Dislocation loops and bubbles became larger in the specimens irradiated with hydrogen ions compared to those irradiated with helium ions. At higher temperature, bubbles were formed preferentially inside the planes of dislocation loops. This is observed at lower temperature under hydrogen ion irradiation than under helium ion irradiation. These differences may be caused by strong trapping of helium atoms at radiation-induced vacancies which retard the growth of loops or bubbles. In the case of hydrogen ion irradiation, enhanced point defect mobility due to hydrogen ions leads to the formation of large loops or bubbles.

The effect of He+ ion irradiation after H+2 ion pre-injection and of simultaneous 25 keV H+2 and 20 keV He+ ion irradiation at RT to 1423 K on the formation of bubbles in TiC crystals were examined. No amorphization occurred under these irradiation conditions. The formation and growth of bubbles produced by He+ ion irradiation is not enhanced by pre-injection of hydrogen atoms at RT. Bubbles are formed but do not grow appreciably by He+ ion, H+2 pre-injection and H+2+He+ dual-ion irradiation at room temperature. Remarkable growth and coalescence occurred during irradiation at high temperature of 1423 K.

The elastic breakup of the deuteron has been measured in a kinematical condition of ${\ensuremath{\theta}}_{p}={\ensuremath{\theta}}_{n}=0\ifmmode^\circ\else\textdegree\fi{}$ at ${E}_{d}=140\mathrm{MeV}$ and 270 MeV on seven targets ranging from $Z=6$ to 82. A double-peaked structure with its minimum at ${E}_{p}\ensuremath{\simeq}{E}_{n}$ is observed for all the measured triple-differential cross sections, which indicates a large contribution from Coulomb breakup. While a symmetric shape is expected for an $E1$ transition, the observed proton-energy distribution is asymmetric, showing considerable dependence on both the target and the incident energy. These data and previous data at 56 MeV have been analyzed using the post-form of the distorted-wave Born approximation (DWBA) theory. Although the calculations account reasonably well for the asymmetric shape, by including the nuclear potential, they consistently overestimate the magnitudes of the cross sections over the whole measured region. Limitations of the post-form DWBA are discussed.

In situ electron microscope observations were performed to investigate damage evolution in Al2O3 single crystals during H2+ ion irradiations in an electron microscope linked with an ion accelerator. The irradiations were made with 15 keV H2+ ions for 1 h at a flux of 1 × 1018 H/m2s at room temperature, 400°C, 650°C and 800°C. It was observed that there were two temperature ranges characteristic of behaviors of the formation and growth of defect clusters. In the lower temperature range below 400°C, dislocation loops and bubbles were formed uniformly. In the higher temperature range above 650°C, bubbles were formed with the dislocation loops almost at the same time, and they located preferentially inside the planes of the dislocation loops. As the irradiation proceeded, the number of bubbles inside the loops increased with the loop growth, but the size of bubbles hardly changed. These observation results seem to indicate that the formation and growth of the bubbles are promoted by the defects on loop planes in a high temperature range.

The double differential cross sections for θlab between 0.0° and 14.7° and the polarization transfer coefficient DNN(0°) for the 27 Al ( p → , n → ) reaction have been measured at a bombarding energy of 295 MeV. A multipole decomposition technique is applied for the cross section data to extract L = 0, 1, 2, and 3 contributions. The Gamow-Teller (GT) strength B(GT) deduced from the L = 0 contribution is compared with the B(GT) values calculated in a full sd shell-model space. The sum of B(GT) values up to 20 MeV excitation is Sβ− = 4.0 ± 0.1 ± 0.1. A fairly large L = 0 contribution is observed in the continuum region up to 50 MeV, which could be in part ascribed to the quenched GT strength. A limit on the effect that the Δ(1232)-isobar nucleon-hole admixture has upon the GT strength is estimated.

Single crystals of yttria-stabilized zirconia were irradiated with 60 keV Xe ions in an electron microscope at several temperatures in the range 300–1473 K and the process of damage evolution was studied. Amorphization did not occur in the zirconia irradiated with 60 keV Xe ions up to the fluence of 1.8×1016 Xe/cm2 at all irradiation temperatures. In the specimen irradiated with Xe ions below 1073 K, defect clusters are formed first and then bubbles are formed. On the contrary, in the specimen irradiated above 1073 K bubbles are formed first and then defect clusters are formed. From the observation of bubble sizes and densities, temperature and dose dependence of bubble swelling were estimated. With increase in fluence or irradiation temperature the average size of the bubble increased resulting in greater values of swelling.

Cross sections and complete polarization transfer coefficients D ij for the charge-exchange 2 H ( p , n )pp reaction have been measured at E p = 346 MeV and θ lab = 0° – 22°. In the forward angles the prominent narrow peak due to the strong 1 S 0 final state interaction (FSI) between the two residual protons is observed while at the large angles the broad bump due to the quasi-free scattering (QFS) becomes prominent. Characteristic features of FSI and QFS are well described by the simple plane-wave impulse approximation (PWIA) calculations.

A detector system of the first focal plane of SMART, the 135 MeV/u high-resolution spectrometer at RIKEN Accelerator Research Facility, is described. It consists of a pair of multi-wire drift chambers and a trigger scintillator hodoscope contained in a He-filled detector box. A major subject using this system is the measurement of the (d, 2 He) reaction making the most of its large angular and momentum acceptances. Without seriously sacrificing the detection efficiency, reasonably good energy and angular resolutions for 2 He, 460 keV and 9 mrad (FWHM), respectively, have been achieved after optimizing the optics property of the spectrometer.

The double differential cross sections at ${\ensuremath{\theta}}_{\mathrm{lab}}$ between $0.0\ifmmode^\circ\else\textdegree\fi{}$ and $12.3\ifmmode^\circ\else\textdegree\fi{}$ and the polarization transfer ${D}_{\mathrm{NN}}$ at $0\ifmmode^\circ\else\textdegree\fi{}$ for the ${}^{90}\mathrm{Zr}(p,n)$ reaction are measured at a bombarding energy of 295 MeV. A multipole decomposition technique is applied to the cross sections to extract $L=0$, $L=1$, $L=2$, and $L=3$ contributions. The Gamow-Teller (GT) strength $B(\mathrm{GT})$ in the continuum deduced from the $L=0$ cross section is compared both with the perturbative calculation by Bertsch and Hamamoto and with the second-order random phase approximation calculation by Dro\ifmmode \dot{z}\else \.{z}\fi{}d\ifmmode \dot{z}\else \.{z}\fi{} et al. The sum of $B(\mathrm{GT})$ values up to 50 MeV excitation becomes ${S}_{{\ensuremath{\beta}}^{\ensuremath{-}}}$=28.0\ifmmode\pm\else\textpm\fi{}1.6 after subtracting the contribution of the isovector spin-monopole strength. This ${S}_{{\ensuremath{\beta}}^{\ensuremath{-}}}$ value of 28.0$\ifmmode\pm\else\textpm\fi{}$1.6 corresponds to about (93 $\ifmmode\pm\else\textpm\fi{}$ 5)% of the minimum value of the sum rule $3(N\ensuremath{-}Z)$=30. The usefulness of the polarization transfer observable in the distorted wave impulse approximation is presented.

Damage evolution and amorphization in TiC due to He + , H 2 + and D 2 + ion irradiation at low temperature were examined by in-situ electron microscopy and EELS observation. He + ion irradiation at 20 K results in the production of a number of dislocation loops and bubbles but no amorphization. 10 keV H 2 + ion irradiation at 20 K causes amorphization at a fluence of about 4.5 × 10 17 (H + )/cm 2 , while 10 keV D 2 + ion irradiation at the same temperature produces amorphization at a fluence of about 9 × 10 17 (D + )/cm 2 . The difference in the fluences necessary for causing amorphization between H 2 + and D 2 + irradiation shows the isotope effect between H and D. H is more favorable for amorphization.

In situ observation of structural changes of Al2O3 and MgAl2O4 induced by Xe and He ion irradiations and successive annealing were performed in an electron microscope equipped with ion accelerator. By Xe ion irradiation amorphization occurred in both the materials and bubbles were formed in MgAl2O4. By He ion irradiation bubbles were formed in both the materials, but amorphization was not observed to a fluence of 1.8 × 1021/m2 (11 dpa). By annealing after the irradiation, bubbles began to grow large by coalescence at 1000°C in Al2O3, and at 900°C in MgAl2O4, respectively. Amorphization began to recover in both materials at these temperatures. In the case of MgAl2O4 amorphous region recovers completely to polycrystalline state at 1000°C, and in the case of Al2O3 to original single crystal, respectively. Pit formation and exfoliation also occur in both materials at about 1100°C.

The processes of damage evolution in TiC crystals irradiated with 25 keV H2+ ions at 12 K and 28 K and 25 keV D2+ ions at 18 K and the effect of annealing after the irradiation were examined by in situ observation with an electron microscope equipped with an ion accelerator. Amorphization was confirmed in TiC irradiated with H2+ ions to a fluence of about 1 × 1021 H2+/m2 at 12 K, while no amorphization occurred in TiC irradiated with D2+ ions to a fluence of 4.5 × 1021 D2+/m2 at 18 K. No amorphization in D2+ irradiation is considered to be due to the difficulty of producing chemical bonding species which suppress the recovery of irradiation induced defects in comparison to H2+ irradiation.

Structural and compositional changes in SiC crystal due to helium ion irradiation were examined by an electron microscope equipped with a thermal field-emission gun and electron energy-loss spectroscope. Amorphization was confirmed both by the shift of the plasmon loss peaks and the change of the carbon core loss peaks in EELS as well as by the change of electron diffraction patterns in SiC irradiated with 12 keV helium ions to a fluence above 6 × 10 19 ions/m 2 at 22 K. He 1s–2p transition peak (21.8–23.8 eV) was observed for SiC irradiated to a fluence above 1.8 × 10 21 ions/m 2 at 22 K. Recrystallization was found to occur during annealing above 1173 K after the irradiation.

The role of immunological surveillance in carcinogenesis is still controversial. In our previous experiments, urethan-induced lung tumorigenesis in athymic (nu/nu) mice and euthymic (nu/+) littermates was examined, and it was concluded that immunosurveillance mediated by T cells could not be demonstrated. However, the reported enhancement of development of various tumors following ionizing radiation might be achieved through modulating the host immunological conditions. In the present experiment,nu/nu and littermatenu/+ mice were treated with 1–4 Gy γ-rays alone at 6 weeks of age or treated with urethan at 0.5 mg/g body weight when aged 14 days followed by 1–4 Gy γ-rays 4 weeks later. Lung tumors were assessed at 6.5 months of age. Ionizing radiation itself caused a very low incidence of these lesions. On the other hand, multiplicities and incidences of lung tumors after urethan treatment at 0.5 mg/g body weight were similar between the two phenotypically different groups of mice (1.66 and 1.84 tumors/mouse, 73% and 80% incidences, fornu/nu andnu/+ cases respectively). This urethan-induced lung tumorigenesis was significantly enhanced by γ-rays in bothnu/nu andnu/+ mice, and the magnitude of tumor enhancement was somewhat higher innu/+ mice than innu/nu mice, especially with a 2-Gy dose. In conclusion, it may be said that lung tumorigenicity of γ-ray irradiation itself and the enhancing effect of radiation on urethan-induced tumorigenesis are scarcely influenced by immunosurveillance mechanisms mediated by T cells

Differential cross sections at θ lab between 0° and 15° and the polarization transfer D NN at zero degrees for the 27 Al, 90 Zr, 208 Pb( p , n ) reactions are measured at a bombarding energy of 295 MeV. A multipole decomposition (MD) technique is applied to extract L = 0, L = 1, and L ≥ 2 contributions to the cross sections. The summed Gamow-Teller strength B (GT) is compared with shell-model calculations for the 27 Al( p , n ) and 90 Zr( p , n ) reactions. The usefulness of the polarization transfer observable in the MD analysis is discussed.

We have designed and constructed a facility to measure the complete polarization transfer coefficient Dij for the (p, n) reaction at intermediate energies. The facility consists of a beam swinger dipole magnet used for angular distribution measurements and a 100 m tunnel for the neutron energy measurement by the time-of-flight method. Typical neutron energy resolution is about 1.85 MeV for 290 MeV neutrons including a contribution of 1 MeV due to the target thickness. The background associated with this tunnel system was carefully investigated and found to be negligibly small. A dipole magnet for the neutron spin rotation is installed in the neutron flight path to measure the longitudinal polarization as well as the induced polarization. The neutron polarimeter which consists of 6 planes of the two-dimensional position-sensitive neutron detectors with a size of 1 m × 1 m × 0.1 m has been constructed. Its effective left-right analyzing power 〈Ayeff〉 has been calibrated at 194, 290 and 384 MeV. The figure-of-merit value defined by 〈Ayeff〉2 × eDS at 290 MeV is 4.05 × 10−4, where eDS is the double scattering efficiency.

Mixtures of aluminum isopropoxide and tetraethoxysilane in 1,4-butanediol were autoclaved at 300 °C for 2 h. The products were then calcined in air to yield silica-modified aluminas. These silica-modified aluminas had high α-alumina-transformation temperatures and maintained significantly large surface areas at elevated temperatures (1000−1300 °C). For example, the product prepared from a mixture of Al/Si ratio 8 transformed into α-alumina at around 1500 °C, and it possessed a surface area of 55 m2/g, even after calcination at 1300 °C for 30 min.

The differential cross sections and the vector and tensor analyzing powers Ay, Ayy, Axx, and Axz for the d-p elastic scattering were measured at Edlab = 270 MeV over the c.m. angular range from 57° to 138°. The data are compared with a Faddeev calculation. A good description is obtained for all components of the analyzing powers, while a discrepancy of about 30% is found in the cross section around θc.m. = 120°.

The reaction of a stoichiometric mixture of aluminium isopropoxide and yttrium acetate in 1,4-butanediol at 300 °C yielded crystalline yttrium aluminium garnet having an approximate particle size of 30 nm. No other phases were detected. Similarly, all the lanthanide elements from Nd to Lu gave essentially single-phase aluminium garnets. Samarium and europium aluminium garnets were also formed by this method, but the products contained corresponding lanthanide acetate oxide. The use of ethylene glycol instead of 1,4-butanediol afforded amorphous products.