Showing papers in "Canadian Journal of Physics in 1966"
TL;DR: In this paper, a detailed discussion of the best straight line calculation by the method of least squares is given, and the most general solution is found and the conditions under which certain previously de...
Abstract: A detailed discussion of the calculation of the "best straight line" by the method of least squares is given. The most general solution is found and the conditions under which certain previously de...
1,561 citations
TL;DR: In this article, the screening function of an interacting electron gas at high and metallic densities is investigated by many-body perturbation theory, guided by a fundamental relation between the c...
Abstract: The screening function of an interacting electron gas at high and metallic densities is investigated by many-body perturbation theory. The analysis is guided by a fundamental relation between the c...
332 citations
TL;DR: In this article, the cold neutron scattering cross section for a system of homonuclear diatomic molecules with arbitrary nuclear spin and an arbitrary ortho-para ratio is calculated in first Born approximation, assuming that the molecular rotation is unhindered.
Abstract: The cold neutron scattering cross section for a system of homonuclear diatomic molecules with arbitrary nuclear spin and an arbitrary ortho–para ratio is calculated in first Born approximation, assuming that the molecular rotation is unhindered. The cross section is expressed in the form of an expansion in terms of the angular momentum transfer. This expansion is shown to be rapidly convergent for all the permanent homonuclear diatomic liquids. To the extent that the intermolecular forces are described by an isotropic Lennard-Jones potential, the terms in the expansion can be calculated with the help of the law of corresponding states and the observed scattering functions for the condensed inert gases. The problem of neutron diffraction by homonuclear diatomic liquids is also investigated.
175 citations
TL;DR: In this paper, the dependence of heterogeneous nucleation of supercooled water drops on temperature and on the duration of super cooling has been studied, where rain-sized drops were placed on an oiled aluminium surface.
Abstract: The dependence of heterogeneous nucleation of supercooled water drops on temperature and on the duration of supercooling has been studied. The rain-sized drops were placed on an oiled aluminium sur...
148 citations
TL;DR: In this article, single-crystal specimens or polycrystalline sinters of cubic NaCl, KCl and KBr were examined by reflection electron diffraction for radiation damage in the form of a phase change from the crystalline to a quasi-amorphous state (metamictization).
Abstract: Single-crystal specimens or polycrystalline sinters of cubic NaCl, KCl, KBr, KI, MgO, CaO, NiO, UC, CaF2, BaF2, UO2, and ThO2 as well as anisotropic TiO2, Al2O3, and U3O8 were bombarded with 40-keV xenon or krypton ions to give integrated ion doses of up to 2 × 1016 ions/cm2. The specimens were examined by reflection electron diffraction for radiation damage in the form of a phase change from the crystalline to a quasi-amorphous state (metamictization). Damage of this kind was observed in all anisotropic crystals; observable lattice disorder without phase change was obtained for MgO. None of the other cubic materials showed any appreciable change in their diffraction pattern, even at the highest dose. The annealing of the disorder in the lattice was correlated with release of the gas at low temperatures for all damaged substances. Significant gas releases at low temperatures were also obtained when much of the gas was in close proximity to the surface. Some other experimental conditions that cause gas rel...
137 citations
TL;DR: In this article, the behavior of a massive star during its final catastrophic stages of evolution has been investigated theoretically, with particular emphasis upon the effect of electron-type neutrino interactions.
Abstract: The behavior of a massive star during its final catastrophic stages of evolution has been investigated theoretically, with particular emphasis upon the effect of electron-type neutrino interactions...
136 citations
TL;DR: The impact theory of Raman line broadening is applied to the broadening of the rotational Raman lines of diatomic molecules arising from electric multipole and anisotropic dispersion forces.
Abstract: The impact theory of Raman line broadening is applied to the broadening of the rotational Raman lines of diatomic molecules arising from electric multipole and anisotropic dispersion forces. Expres...
117 citations
TL;DR: In this paper, self-broadening of the rotational Raman lines of O2, N2, CO2, and CO 2 were measured in the pressure range from 7 to 43'atm at room temperature.
Abstract: Self-broadening of the rotational Raman lines of O2, N2, CO2, and CO, and foreign-gas broadening of O2 and N2 by He and Ar were measured in the pressure range from 7 to 43 atm at room temperature. ...
115 citations
TL;DR: A long progression of absorption bands appearing in the region 5'500 -8'200'A has been observed in the flash photolysis of dibromochloromethane, HCClBr2 as discussed by the authors.
Abstract: A long progression of absorption bands appearing in the region 5 500–8 200 A has been observed in the flash photolysis of dibromochloromethane, HCClBr2. Observation of chlorine and deuterium isotop...
95 citations
TL;DR: In this paper, the collision-induced rotation of the fundamental and first overtone bands of oxygen and nitrogen has been observed in the pure gas at pressures of a few atmospheres, and in mixtures of these gases with argon at a few tens of atmospheres.
Abstract: The collision-induced rotation–vibration fundamental and first overtone bands of oxygen and nitrogen have been observed in the pure gas at pressures of a few atmospheres, and in mixtures of these gases with argon at pressures of a few tens of atmospheres. From the integrated intensities of the bands it is possible to deduce a value for the first derivative of the quadrupole moment with respect to internuclear distance; we find that |Q′| = 1.6ea0 for oxygen, and |Q′| = 0.95ea0 for nitrogen.
95 citations
TL;DR: In this paper, a new transient absorption spectrum belonging to the HCF free radical was discovered in the flash photolysis of dibromofluoromethane, HCFBr2.
Abstract: A new transient absorption spectrum, belonging to the HCF free radical, has been discovered in the flash photolysis of dibromofluoromethane, HCFBr2. The spectrum consists of a single progression of complex bands in the region 4 300–6 000 A. Rotational analysis of the less severely perturbed bands shows them to be type-C bands of a molecule that is nonlinear in both upper and lower states of the transition, with bond angles of ~ 127° and ~ 102° respectively. Axis-switching effects, due to the large change of bond angle in the transition, cause the appearance of prominent gQ, qQ, and °Q branches, in addition to those obeying the ordinary type-C selection rules.The principal molecular constants of HCF (in cm−1) are:
TL;DR: In this paper, the surface properties, temperature effects, cooling behavior, and observability of neutron stars have been studied, and the opacity of the surface layers is calculated both for a pure iridium and a pure neutron star.
Abstract: Surface properties, temperature effects, cooling behavior, and observability of neutron stars have been studied. For this purpose, the opacity of the surface layers is calculated both for a pure ir...
TL;DR: In this paper, the density of states and momentum distribution of conduction electrons in liquid metals are calculated for Al, Zn, and Bi. The theory used is a perturbation expansion of the Green function in the...
Abstract: The density of states and momentum distribution of conduction electrons in liquid metals are calculated for Al, Zn, and Bi. The theory used is a perturbation expansion of the Green function in the ...
TL;DR: The proton total reaction cross sections of 41 elements have been measured at 99 MeV, using a double Faraday cup to measure the proton-beam attenuation.
Abstract: The proton total reaction cross sections of 41 elements have been measured at 99 MeV, using a double Faraday cup to measure the proton-beam attenuation. The results are consistent with the semiclas...
TL;DR: In this article, the absorption spectrum of the NO molecule has been continued on plates taken in the fourth order of a 10.5m vacuum spectrograph, where the spectra of 14N16O, 15N 16O, 14N18O, and 15N 18O gases, each kept at liquidoxygen temperature, were photographed separately.
Abstract: The study of the absorption spectrum of the NO molecule has been continued on plates taken in the fourth order of a 10.5-m vacuum spectrograph. The spectra of 14N16O, 15N16O, 14N18O, and 15N18O gases, each kept at liquid-oxygen temperature, were photographed separately. Rotational analyses were carried out for many bands observed below 1 600 A. Constants for levels of the Rydberg complexes 3p, 4s, 4p, and 5s have been derived. These levels include ν = 5 and ν = 6 of the C2Π state, levels that interact with the levels ν = 21 and 24 respectively of the configurationally different B2Π state. It is shown that the vibrational levels, now well established above the energy where the potential curves of the C and B states cross, are to be attributed to "crossing" curves.The level ν = 4 of the L2Π state, which was discerned in the spectra of the heavier isotopes only, coincides in 14N16O with the level ν = 6 of C2Π and produces a strong three-level perturbation. The level, perturbed in this way, has the appearance...
TL;DR: In this article, the emission spectrum of NO between 1'600 and 1'400'A was studied with a 1m vacuum spectrograph, consisting of the two types of mutually perturbing 2Δ-X2Π bands already known from the much m...
Abstract: The emission spectrum of NO between 1 600 and 1 400 A has been studied with a 1-m vacuum spectrograph. It consists of the two types of mutually perturbing 2Δ–X2Π bands already known from the much m...
TL;DR: Composite equations of state for determining effects of nuclear forces on neutron star models were used in this paper for determining the effect of nuclear force on the neutron star model and its properties.
Abstract: Composite equations of state for determining effects of nuclear forces on neutron star models
TL;DR: In this paper, it was shown that the small penetrating component observed in the range distribution of keV projectiles in tungsten single crystals is caused by a diffusion process and not, as previously believed, by a "super-range" phenomenon.
Abstract: Experimental evidence is presented to show that the small penetrating component observed in the range distribution of keV projectiles in tungsten single crystals is caused by a diffusion process and not, as previously believed, by a "super-range" phenomenon. We suggest that a few of the injected atoms, probably the most perfectly channeled ones, come to rest interstitially. These interstitial atoms then diffuse rapidly, even at room temperature, until trapped by some defect or impurity atom in the lattice. The concentration of traps required to fit the experimental data is 1015-1016 per cm3. Various factors affecting such an interstitial diffusion mechanism are discussed.
TL;DR: In this paper, the degenerate ν10 and ν11 Raman bands of C2H6 have been photographed at a spectral resolution of ~0.4 cm−1 and a gas pressure of 1 ǫ atm.
Abstract: The degenerate ν10 and ν11 Raman bands of C2H6 have been photographed at a spectral resolution of ~0.4 cm−1 and a gas pressure of 1 atm. The rotational structures of both bands were analyzed. The analysis of the ν10 band gave A0 = 2.671 ± 0.005 cm−1 for the ground-state rotational constant A0. Although this value is between 3 and 4% higher than previous determinations, the method of analysis indicates that it must be considered the most reliable yet obtained. This new value of A0 has been used, with other data, to recalculate the ground-state geometrical structure of ethane.
TL;DR: The ultraviolet spectrum of the free CNC radical has been discovered in the flash photolysis of diazoacetonitrile, HC(CN)N2 as discussed by the authors.
Abstract: The ultraviolet absorption spectrum of the free CNC radical has been discovered in the flash photolysis of diazoacetonitrile, HC(CN)N2. The identity of the radical has been proved from isotopic evi...
TL;DR: Hall effect and electrical conductivity measurements were performed on Cu2O single crystals both before and after heating the samples in vacuo at temperatures ranging from 200 °C to 800 °C as mentioned in this paper.
Abstract: Hall-effect and electrical conductivity measurements were performed on Cu2O single crystals both before and after heating the samples in vacuo at temperatures ranging from 200 °C to 800 °C. Both th...
TL;DR: In this paper, a new system of diffuse bands in the region 2'900 to 3'450'A has been found during the flash photolysis of propargyl bromide, prop argyl chloride, methyl acetylene, allene, and other compounds.
Abstract: A new system of diffuse bands in the region 2 900 to 3 450 A has been found during the flash photolysis of propargyl bromide, propargyl chloride, methyl acetylene, allene, and other compounds. Isotopic studies have been carried out with five isotopically labeled parent compounds. The new bands are assigned to the propargyl radical, CH2—C≡CH. The diffuseness of the bands is attributed to predissociation of the radical in the excited state and gives an upper limit of 86.0 kcal/mole for the dissociation energy of the radical.
TL;DR: In this article, the vibrational and rotational constants of the b1Σ+−X3Σ− transition of the SO molecule have been determined: ωc′ = 1067.66 cm−1, Bc′
Abstract: The 0–0, 1–1, 2–2, and 0–1 bands of the b1Σ+–X3Σ− transition of the SO molecule have been observed in the afterglow produced when COS + O2 is pumped rapidly through a microwave discharge. The two strongest bands, 0–0 and 1–1, which lie respectively at 9549.08 and 9626.13 A, have been photographed at high resolution and have been analyzed. Using the known X3Σ− rotational constants, the vibrational and rotational constants of the 1Σ+ state (Tc = 10 509.97 cm−1) have been determined: ωc′ = 1067.66 cm−1, Bc′ = 0.70262 cm−1, and rc′ = 1.5005 A. Rotational intensity distributions for 1Σ+–3Σ− transitions are discussed. The a1Δ state of SO is predicted to lie at T ~ 6350 cm−1.
TL;DR: In this article, the fundamental absorption bands of deuterium and hydrogen deuteride have been observed in the solid at a temperature of 19 °K Features correspond to rotation-vibration transitions in single molecules, in pairs of molecules, and to molecular transitions accompanied by the creation of phonons.
Abstract: The fundamental absorption bands of deuterium and hydrogen deuteride have been observed in the solid at a temperature of 19 °K Features are observed that correspond to rotation–vibration transitions in single molecules, in pairs of molecules, and to molecular transitions accompanied by the creation of phonons Several features were observed in the HD spectrum that arise from the fact that HD is heteronuclear; one of these was a sharp absorption line due to ΔJ = 1 transitions in single molecules In addition, an unusual split-phonon branch was observed with a minimum of zero absorption a few wave numbers below the frequency of the ΔJ = 1 transition This split-phonon feature is apparently a result of strong interaction between the rotation of the molecule and its translational motion in the lattice The spectrum of a solid mixture of 10% HD and 90% H2 was also studied The phonon branch accompanying the Q1(0) line of HD and the phonon branch accompanying the Q1(0) line of H2 observed in the same crystal
TL;DR: In this paper, the fraction of the incident electrons reflected elastically from the (100, (211), (111), and (110) crystal faces of tungsten has been measured m the incident energy range 1 −28 eV.
Abstract: The fraction of the incident electrons reflected elastically from the (100), (211), (111), and (110) crystal faces of tungsten has been measured m the incident energy range 1–28 eV. The fraction reflected by the (100) and the (211) faces was changed dramatically by hydrogen adsorption. The size of this change and its variation with energy are comparable with the differential scattering of electrons by atomic hydrogen. The fraction reflected by the (111) surface was small and changed only slightly with hydrogen adsorption. No change was observed in the reflection of electrons from the clean (110) surface when it was exposed to hydrogen.The change in work function of the four faces on exposure to hydrogen has also been measured, and has been found to be large and positive for the (100) and the (211) surfaces, small and positive for the (111) face, and zero for the (110) surface.
TL;DR: The first evidence for the existence of iodine monofluoride (IF) was provided by Durie as mentioned in this paper, who observed a well-developed band system in the emission from an iodine-fluorine flame.
Abstract: Observation by the author (Durie 1951) of a well-developed band system in the emission from an iodine–fluorine flame provided the first evidence for the existence of iodine monofluoride (IF), the l...
TL;DR: A plane-wave analogue model for studying the effect that various geological structures have on the natural electromagnetic variations observed at the surface of the earth is discussed in this article, where the validity of the model is examined.
Abstract: A plane-wave analogue model for studying the effect that various geological structures have on the natural electromagnetic variations observed at the surface of the earth is discussed. The validity...
TL;DR: In this article, an alternative formulation of the method developed by Nogami to eliminate the effect of the number fluctuation in the superconductivity approximation for the nuclear pairing interaction is given.
Abstract: An alternative formulation of the method developed by Nogami to eliminate the effect of the number fluctuation in the superconductivity approximation for the nuclear pairing interaction is given. T...
TL;DR: In this article, the transformation of a region composed initially of 28Si to nuclei in the vicinity of the iron peak, which is thought to take place in the late stages of evolution of some stars, is considered.
Abstract: The transformation of a region composed initially of 28Si to nuclei in the vicinity of the iron peak, which is thought to take place in the late stages of evolution of some stars, is considered in ...
TL;DR: In this paper, a theoretical interpretation of homogeneous perturbations for the case of two electronic excited states that differ strongly in electron configuration is proposed, where the interaction parameter H can be expressed in terms of the vibrational overlap integral and the electrostatic interaction between the two states.
Abstract: A theoretical interpretation of homogeneous perturbations is proposed for the case of two electronic excited states that differ strongly in electron configuration. The interaction parameter H can be expressed in terms of the vibrational overlap integral and the electrostatic interaction between the two states. In the case of the Π–Π and Δ–Δ interactions in the spectrum of the NO molecule, a semi-empirical calculation of this parameter is made, using Morse functions for the vibrational part and the LCAO-MO SCF function for the electronic part. The comparison with the "experimental" values given by Lagerqvist and Miescher supports this interpretation.