The photoneutron cross section of S³² was observed up to 22 MeV with good energy resolution, together with the photoneutron spectrum using a stilbene scintillation spectrometer. Fine structures were observed in either of the two measurements. Taking into account the threshold energy and the excitation energies of the residual nucleus, these structures have been shown to be consistently related with each other.
Experimental results were discussed using the statistical model calculation, assuming that the emitted particles were only p-wave and f-wave particles. The integrated cross section ratio for S³² (γ, n) to P³¹ (γ, n) reaction and the same ratio for S³² (γ, p) to S³² (γ, n) reaction were well explained by the calculations. The difference between the energy spectrum of the photoprotons from P³¹ and that from Si²⁸ also seemed to be well explained qualitatively. In the appendix, the contributions of the f-wave protons for the energy spectrum of photoprotons were shown.
Summarizing the discussions, the photodisintegration of nuclei in these mass number region was concluded to occur mainly through the compound process in the giant resonance energy region.

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The neutron total cross sections of silicon, phosphor, sulfur, and chlorine in the energy range from 3 to 5 MeV have been measured with an energy resolution of 20 to 50 keV, and the variations of the cross sections with energy have been analyzed statistically under the assumption that the variations arise from the fluctuation of the neutron widths and spacings of the resonances which are covered by the energy resolution. The average spacings D, which are obtained by the present analysis, are 1.3, 0.13, 0.54, and 0.04 keV for silicon, phosphor, sulfur, and chlorine, respectively. These values agree well with those calculated by Cameron’s semi-empirical formula. The neutron strength functions ⟨Γ_n⁰⟩⁄D, which are obtaind also by the present analysis, are 2.9, 3.9, 3.8, and 4.7×10⁻⁴ for the respective elements, and are consistent with those obtained by the low-energy-neutron experiments. The correlation between the fluctuation of the total cross sections and the energy are obtained, and it is pointed out that there appear no signs of the fluctuations due to the existence of the large resonances, the width of which are comparable with or larger than the energy interval of about 100 keV.

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Using ∼22–MeV alpha particles the angular distributions of protons from (α, p) reactions on B¹⁰, C¹², N¹⁴, Na²³, Mg²⁴, P³¹, S³², Ca⁴⁰, Sc⁴⁵, Mn⁵⁵, Fe⁵⁴, Fe⁵⁶ and Co⁵⁹ were measured. The angular distributions on the light nuclei show diffraction-like patterns, but those on the medium-weight nuclei are peaked at forward angle and decrease monotonically with angle. These angular distributions are fitted with theories of a stripping reaction. At first they are compared with a theory obtained by using plane-wave approximation for wave functions of incoming alpha particles and outgoing protons. They are also compared with a theory using a simple distorted-wave approximation which fits better with the experimental results. The values of parameters in the theoretical formula show systematic differences in cases that tritons are captured by target nuclei with angular momenta 0 and 2. Some results on spectroscopic investigations of the target or residual nuclei are also discussed. The (α, p), (α, n) and (p, α) reactions have a strong energy dependence near 20–MeV excitations (the giant resonance region), and above this region their energy dependences become smaller.

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The yield of photodeuterons has been investigated by using an improved method of grain counting developed by the present author. Grain density distributions of photodeuterons and photoprotons were clearly separated by density ratios 1.25–1.30 being in good accord with the value predicted for deuterons and protons by a former work.
In the case of antimony, ratio of the yield of photodeuterons to that of photoprotons were determined to be as high as 0.13±0.05 measured at the maximum bremsstrahlung energy of 24.0 MeV, which is in agreement with a value reported by Medicus. An energy spectrum of photodeuterons from antimony exhibited a peak in an energy region 8–9 MeV. The ratio for copper at an X-ray energy of 25.5 MeV were 0.06±0.04 and 0.04±0.02 measured at 90° and 126° to the X-ray beam, respectively. These values are the same order of magnitude as a value determined recently by Hamburger using a method of magnetic field and plates, but are inconsistent with values hitherto reported by all the other investigators. For nickel and tin, values of approximately 0.02 for 25.5 MeV X-rays and 0.04 for 24.0 MeV X-rays, respectively, were obtained for the ratio.

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Oxygen 18 was bombarded with protons having energies over a range from 570 keV to 1500 keV, and proton capture gamma rays were studied. Four resonance levels were observed at proton energies 628, 847, 1167, and 1397 keV, and their widths were estimated to be 2.7, 44, 0.6 and 3.7 keV, respectively. From an analysis of angular distributions of gamma rays emitted from the resonance level at E_p=1167 keV, it was deduced that spin values of the 9.07–, 2.78–, and 1.35–MeV levels of F¹⁹ were 7/2, 9/2, and 5/2, respectively. The results were compared with the theoretical predictions based on shell model and collective model calculations.

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An evaluation is carried out for the renormalization constant Z of an interacting electron gas. It is shown that the lowest approximation with respect to effective interaction between electrons leads to Daniel and Vosko’s result for Z, while higher order correction for Z modifies their result appreciably and their result is not correct even in the limit of high density.

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The effects of magnetic field on the negative resistance characteristics of highly compensated P-type germanium at 4.2°K are presented. It is shown that the sustaining field strength, E_s, varies linearly with the magnetic field, H.
When the magnetic field strength is sufficiently high an oscillation phenomenon is observed in the sutaining region.
The value of E_c, the electric field strength at the critical point, shows an angular dependence on the transversal magnetic field. This angular dependence is different for different transversal magnetic field strength.

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The hardening of copper single crystals irradiated with about 10¹⁶ fast neutrons/cm² in a pile at about 90°K was investigated and the recovery of the hardening by annealing at up to room temperature was studied. A bump was always observed in the region of easy glide if the crystal had not been annealed by more than 30 minutes at 0°C, as Makin already observed. Small serrations were also observed in the region of easy glide before the bump, and they disappeared at the same annealing condition as the bump. A divacancy mechanism is proposed to explain these observations.

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The Brookhaven National Laboratory’s slow chopper was used to investigate the low frequency motions of hydrogen in KH₂PO₄ and KD₂PO₄ at room temperature and below the ferroelectric Curie temperature. The energy interval covered (8∼170×10⁻³ ev) corresponds to wave numbers of 25∼1300 cm⁻¹, a region which is difficult to be investigated by infrared absorption technique. The excitation modes associated with hydrogen are identified by the change in scattering intensity upon deuteration. It is found that a band of frequencies centered around 180 cm⁻¹ is associated with the hydrogen vibrations. A comparison with Reid’s semi-empirical theory for KH₂PO₄ is made.

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Measurements have been carried out on Ca_x Ba_1−x TiO₃ ceramics for which 0≤x≤0.19. The thermal diffusivity was measured from −60° to 230°C and the thermal conductivity was measured from 40° to 150°C. The electrical properties were also measured as a function of temperature. The velocities of dilatational elastic waves were measured for these ceramics at room temperature. The increase in the thermal resistance with increasing x-value is accounted for within the limits of error of the measurements by using a Debye distribution for the phonon spectrum and attributing the phonon scattering to the mass difference between the Ba atoms and the substitutional Ca atoms.

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Magnetocrystalline anisotropy was measured for Mn-Zn-Fe ternary ferrites from liquid oxygen temperature to the Curie point by means of torque magnetometer, using a number of monocrystals.
Anisotropy constant K₁ increases monotonically from that of the pure Mn ferrite with the increase of the content of ZnO. On the other hand, the introduction of a small amount of ferrous ions into Mn-Zn ferrites has a remarkable effect of increasing K₁ in positive sense. It was found that there is a region of exhibiting a positive K₁ at room temperature in the Mn-Zn-Fe ternary diagram.
A feature of the temperature dependence of permeability μ can be interpreted in terms of a thermal change of K₁. The origin of the second maximum in μ versus T curve which is often observed near room temperature for many Mn-Zn ferrites is considered to be corresponding to the point of K₁=0.
The compositional dependence of the permeability is interpreted from those of the magnetocrystalline constant and the Curie point.

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Broadening of infrared absorption lines due to localized modes of lattice vibrations of U-centers in alkali-halide crystals is investigated by taking into account vibration anharmonic terms. A model is assumed such that a vibration spectrum of an ionic crystal is modified by the presence of a U-center, thus giving rise to a few localized modes whose frequencies lie outside the continuous spectrum (about three times as large as the frequency of the optical mode), and general anharmonic parts are expanded in terms of these vibration normal coordinates. It is shown that third-order terms are ineffective because of an energy conservation relation, and that fourth-order terms each involving three optical modes and one localized mode are responsible for the broadening. The absorption line is of a Lorentzian shape. A simple expression for the damping constant is derived which yields a relation between the linewidths and the ratio, hω_op^*⁄kT, where ω_op^* is the optical-mode frequency for a given lattice, and is compared with the experimental results of Schaefer. A good agreement is obtained concerning both the temperature and the frequency (ω_op^*) dependences that confirms the proposed mechanism of the line-broadening, i.e. fourth-order anharmonic broadening considered in the present paper.

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The optical constants n and k of a germanium single crystal in the extreme ultraviolet region, from 10.2 to 23.4 eV, have been determined by the reflectance measurements. Energies of the plasma oscillation estimated from the real part of the dielectric constant, and the imaginary part of the reciprocal dielectric constant are 14.7 and 16.4 eV, respectively, suggesting that the characteristic energy loss of fast electrons observed at 16.4 eV is just caused by the collective excitation of electrons as expected from the free-electron approximation.
The tangential plasmon energy is also estimated at about 13 eV, corresponding to the value of subsidiary electronic loss observed by Powell at 11 eV.

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Simpler formulae have been derived for the second approximation to the thermal diffusion factor of a binary gas mixture starting from the rigorous expression given by Mason on the extended Kihara approximation scheme. These formulae have been further specialised for the particular cases when either of the two components is in trace. The new formulae are considerably simpler than the corresponding rigorous expressions and are therefore preferable for numerical computations. The accuracies of these formulae are demonstrated by performing numerical calculations for the systems Ar-Xe and He-Xe both as a function of temperature and composition.

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The self-pinch motion of a cylindrical plasma is analyzed by using the two-fluid model of electrons and ions. The Lorentz force caused by currents flowing through the plasma along the cylindrical axis acts only on the electrons, because most part of the current is carried by the electrons. Thus the charges are separated and the electric field is induced in the radial direction. The ions are accelerated secondarily by this electric field. As the initial rate of increase of the currents increases and the plasma density decreases, the charge separation becomes greater. Depending on the magnitudes of these quantities the motions are classified into two types, namely the thorough charge separation and the plasma oscillation after the separation. Numerical examples show that the behaviors of the plasma are different from the result obtained by the one-fluid model.

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Hydrodynamic theory of transient pinched plasma is presented. The study is concerned with the case in which a cylinder of a perfectly conducting plasma is compressed by an extremely strong magnetic pressure induced by an impulsively applied electric current and a converging shock wave propagates into the plasma.

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A general method for computing electronic energies and wave functions of diatomic molecules is described and arranged in such a way that the processes of the computation are carried through systematically and fully automatically by an electronic computor. The number of electrons in the molecule concerned, values of the nuclear charges and symmetry properties of the molecule are the necessary informations. Symmetry adapted basic functions made up from molecular orbitals are automatically generated and the energy matrix involving them is calculated by using representation matrices of permutation groups.

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It was concluded that the hyperfine structure observed on 1% Mn in Pd alloy should be attributed to Mn⁺⁺ ion in PdO which was produced on the surface of particles during the preparation of fine-powdered specimen. The existence of PdO was confirmed on these particles by X-ray diffraction, and no hyperfine structure was observed on newly prepared coarse specimens showing a metallic lustre.
Two kinds of resonance absorption lines have been observed on reliable specimens. One of them is observed on every alloy including pure Pd metal at temperatures lower than about 100°K, and has a large width of several thousand gauss. The other narrower line can be observed at room temperature, and the intensity increases with the concentration of Mn. Further details will be published in future.
The authors should like to express their thanks to Dr. D. Shaltiel in Bell Telephone Labs. who pointed out these mistakes and showed his results before publication.

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