bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Energy Level in 20Ne at 10·31 MeV
Authors: Sargood DG , Putt GD
Published: May 2011

Neutron-gamma-ray coincidence measurements have been made in the reaction 19F(d,ny),oNe at bombarding energies between 500 and 700 keV. Time offlight determination of neutron energy indicates a new energy level in .oNe at lO� 31 �O' 07 MeV. From angular distributions of the neutrons, and observation of the gamma -decay spectrum of the 10.31 MeV state, spin and parity of 1 + are inferred for this state.
A Study of Whistling Atmospherics. IV. Comparison of Observations at Widely Spaced Stations
Authors: Crouchley J
Published: May 2011

Whistlers observed at stations separated from one another by up to 3000 km are examined statistically and by comparing simultaneous whistlers. It is shown that whistlers are not commonly observed further than 1000 km away from their "ionospheric source", i.e. the limited region through which they emerge from the ionosphere, and that a lightning stroke may produce whistlers with different dispersions at stations with a separation of this order of magnitude. Ionospheric sources are most common around (geomagnetic) latitude 44-46� in winter and around latitude 50-52� in summer (southern hemisphere). It is suggested that this change is related to changes in the electron density of the ionosphere.
A Study of Whistling Atmospherics. V. Dispersion
Authors: Crouchley J
Published: May 2011

The dispersion characteristics of whistlers recorded at Brisbane, Adelaide, and Hobart, mainly during the lGY, are examined. The dispersion recorded at each station shows a wide range of values. Diurnal (10-15 st) and annual variations (20-25 si) are observed and correlations between dispersion and F. critical frequency and dispersion and magnetic disturbance are discussed. No association between dispersion and sunspot number was detected. The position of the "ionospheric sources" of the whistlers is of prime importance as dispersion varies with geomagnetic latitude. Much of the variation in dispersion observed by individual stations is believed to be due to their being able to "see" ionospheric sources up to 100 away.
Extended Radio Sources. I.
Authors: Milne DK , Scheuer PAG
Published: May 2011

Twenty�one "extended sources" from the catalogues of Mills, Slee, and Hill have been observed with a 14' arc pencil beam at 1400 Mc/s. Some appear to be irregularities in the galactic radio emission, but most, especially those at high galactic latitudes, are resolved into groups of sources of small angular diameter. Maps of the regions are shown, and so far as possible radio spectra of the component sources have been assembled. An optical identification is given for the principal component of MSH 00-017 (3C29), and tentative identifications are suggested for some other sources.
Complex Singularities in Production Amplitudes
Authors: Cunningham J
Published: May 2011

Complex singularities in the ",+N --? "'+ ",+N amplitude corresponding to vertex contractions of the single-loop Feynman diagram exist on the physical sheet of the amplitude irrespective of whether the theory is formulated in terms of timeordered or retarded products_
The Evolution of Massive Stars Initially Composed of Pure Hydrogen
Authors: Van Der Borght R
Published: May 2011

The object of the present paper is to investigate the influence of carbon abundance on the evolution of the massive stars, initially composed of pure hydrogen, during the pre-main-sequence contraction and the hydrogen burning phase of these stars_
Collision Broadening in the Inversion Spectrum of Methyl Chloride at Pressures up to Two Atmospheres
Authors: Burton CH , Lasich WB , Noon JH , Parsons RW
Published: May 2011

The power absorption coefficient a of microwaves of wave number v = 0� 333cm-1 by methyl chloride at 33� 7�C has been studied at pressures up to 2 atm, and the results are compared with theoretical predictions. Discrepancies which have previously been attributed to the effect of transitions between low.lying rotational states are shown to be due to three� body collisions. The collision diameter for pressure broadening of theinversion transition in methyl chloride is found to be 8�6 A; this is significantly larger an the figure of 7 . 2 A reported by earlier workerswho neglected the effect of three-body ollisions.
The Effect of Wave-damping on the Surface Velocity of Water in a Wind Tunnel
Authors: Fitzgerald LM
Published: May 2011

A laboratory wind tunnel has been used to study the movement of the surface of a body of water over which a wind is blowing. The ratio of the surface velocity Us to the wind velocity V has been measured for both smooth and wavy surfaces at wind speeds between 350 and 750 cm/s. It has been found that this ratio is markedly affected by the damping-out of surface waves. For a wavy surface, as obtained with clean water, us/V has a constant value of about 0�03. The damping of the surface waves is achieved by the addition of detergent solution to the water. There is a particular concentration of detergent, and a corresponding surface pressure, at which u s/ V ceases to have this constant value and begins to rise to' values around 0�045. For a fully damped surface us/V rises linearly with V for low wind speeds and tends to a constant value of 0�045 for wind speeds greater than 550 cm/s. These findings are, to some extent, in conflict with the observations and theories of previous workers.
Quiet Day Solar Daily Magnetic Variations at Toolangi, Victoria
Authors: Winch DE , Slaucitajs L
Published: May 2011

The results of analysis of the quiet day solar daily magnetic variations (Sq) are given in the form 1: Cn sin(nt+.pn), for n = 1,2,3,4, of all magnetic elements as recorded at oolangi Observatory, Victoria, during the years 1949--1958, as well as the times of ccurrence of extrema and the percentage contributions of each harmonic to each extrema.
Anharmonic Contributions to the Vibratory Free Energy of a Lattice
Authors: Lloyd P
Published: May 2011

The anharmonic contribution to the free energy of a lattice is evaluated by means of a Bethe approximation. The approximation is accurate to within 3% for the model valuated by Maradudin, Flinn, and Coldwell� Horsfall. The anharmonic contribution to the specific heat at constant volume of a model of sodium is evaluated.The specific heat is found to increase as the temperature rises but the rate of increase is lower than the observed value
Fan-beam Observations of Radio Sources at 21 cm Wavelength
Authors: Labrum NR , Krishnan T , Payten WJ , Harting E
Published: May 2011

The compound interferometer at Fleurs, N.S.W., has been used in observations of eight of the strongest radio sources, with a fan beam 1'� 53 wide at a wavelength of 21� 1 cm. Each of the sources was scanned from west to east; the brightness distributions in this direction have been observed, and the positions of the sources in right ascension have been determined with high absolute accuracy (probable error less than 1 s of time).
The Parkes Catalogue of Radio Sources Declination Zone ?20° to ?60°
Authors: Bolton JG , Gardner FF , Mackey MB
Published: May 2011

A catalogue of 297 radio sources between declinations -20� and -60�, has been compiled from observations with the Australian 210-ft telescope. The sources were selected from a survey at 75 cm wavelength as having flux densities in excess of 4 X 10-26 W m-2(cJs)-1. The survey did not cover a small area near the galactic plane. Additional measurements were made at wavelengths of 21 and 11 cm. Results on source identification, spectra, and polarization are discussed.
Sodium Chloride Sensitizing of Far Ultraviolet Spectrum Plates
Authors: Burrows KM , Kelly JC , Ellis DE
Published: May 2011

It is well known that the absorption spectra of some crystals may be permanently changed if the crystals are exposed to photons with energies of tens or hundreds of electron-volts. It is therefore desirable, when studying absorption of far ultraviolet radiation in an ionic crystal, to expose it only to radiation of the wavelength for which its absorption is to be determined, rather than to a wide range of wavelengths. The usual techniques do, in fact, expose the crystal to the whole spectrum over which absorption measurements are equired - either simultaneously (before dispersion) or sequentially (as with a scanning monochromator).
Gauge-independent Theory of Symmetry. I.
Authors: Tassie LJ , Buchdahl HA
Published: May 2011

The invariance of a system under a given transformation of coordinates is usually taken to mean that its Lagrangian is invariant under that transformation. Consequently, whether or not the system is invariant will depend on the gauge used in describing the system. By defining invariance of a system to mean the invariance of its equations of motion, a gauge-independent theory of symmetry properties is obtained for classical mechanics in both the Lagrangian and Hamiltonian forms. The conserved quantities associated with continuous symmetry transformations are obtained. The system of a single particle moving in a given electromagnetic field is considered in detail for various symmetries of the electromagnetic field, and the appropriate conserved quantities are found.
Integral Equations for Three-particle Interaction Amplitudes in the Non-Relativistic Case
Authors: Komarov VV , M Popova Anna
Published: May 2011

By using the technique of summing an i,"finite series of non-relativistic graphs, accurate integral equations are obtained for the three-particle interaction amplitudes.
Measurements of Townsend's Energy Factor k1 for Electrons in Carbon Dioxide
Authors: Rees JA
Published: May 2011

Values of Townsend's energy factor kl for electrons in carbon dioxide have been determined as a function of the parameter E/p for 0�1 .;;; E/p .;;; 50 at a temperature of 293�K. The results are compared with those of other investigators and are used in a recomparison of the cross sections for electron attachment deduced from swarm and beam types of experiments for swarms of electrons having mean energies of up to 5 eV.
Volcanic Particles in The Stratosphere
Authors: Harris Beverley
Published: May 2011

Measurements of intensities of sunlight reflected from a balloon during sunset indicate an above-average concentration of dust at stratospheric levels. Our results for May 1964 (combined with the results obtained by CSIRO from direct sampling of particles from aircraft) may be explained by the presence at 20-km altitude over Victoria of oncentrations of the order of either (i) 500 000 metallic Aitken nuclei per litre, or (ii) a few thousand large aerosols per litre of tl).e types observed in aircraft collections, but with thick coatings of dielectric material, or by the presence of both (i) and (ii).
Preliminary Results of Observations of Aspect-sensitive Reflections from Irregularities in the F Region
Authors: M Swenson Evelyn
Published: May 2011

Night-time radio reflections from irregularities in the F. region of the ionosphere have been studied at Brisbane (geomagnetic latitude - 35.8�), at a fr-equency of 16 Mc/s. The spatial limits and behaviour of the echoes were consistent with the hypothesis of specular reflections from field-aligned columns of ionization, with observational limitations imposed by echo surface configuration, aerial sensitivity, range attenuation, and absorption. The echoes, recorded with range-azimuth display, were of many shapes, but only a U-shape tended to recur. These U-echoes were preferentially observed under conditions of magnetic disturbace. Irregularity occurrence possibly increased with latitude from 45� to55� geomagnetic latitude. No definite relationship was found between the echoesand v.l.f. noise, radio-star scintillations, spread-F, or auroras.
Motion of a Charged Particle in a Non-uniform Magnetic Field
Authors: Mathams RF
Published: May 2011

The motion of an electron in a magnetic field of constant gradient has been analysed by Seymour (1959), who derives expressions for the x and y coordinates of the electron in terms of elliptic integrals.
Inelastic Collisions for Small Momentum Transfers
Authors: Cunningham J
Published: May 2011

Let us denote by Pi> i = 1, 2, ... , 5, the four-momenta of the internal lines of the five-point single-loop graph (p~ = fLi). Each vertex may then be labeled by two suffices and we shall denote the four-momenta of the external particles (measured formally as incoming) by P12 = PI' P23 = P2, ... ,P51 = P5 (P~ = M~). Scalar product variables may be constructed as follows
Electric Dipole Photon Absorption in 32S
Authors: Spicer BM
Published: May 2011

The particle-hole model has been applied to the calculation of E1 photon absorption by 32S. A plausible unperturbed spectrum was obtained from investigation of the results of the 32S(d, p)32S and 32S(d, 2p)31P reactions. The results of the calculation are compared with experiment, and suggestions are made with reference to the shortcomings of the calculation.
The Photonuclear Giant Resonance in Silicon?28
Authors: Parker AW , Whitehead RR , Shute GG
Published: May 2011

The 90� yields of ?-rays from the reaction 27Al(p,?)28Si have been obtained at intervals of 40 keV for proton energies between 8�02 and 10�42 MeV. The ground state y-ray (?o) and the first excited state y-ray (?l) were adequately resolved. The two yield curves show considerable structure and, with the present resolution, there is a strong one-way correspondence between them. The gross structure of the ?o yield curve is compared with data from the 28Si(?,n)27Si reaction and fair agreement is found.
A Spectroscopic Study of a Decaying Hydrogen Plasma
Authors: Irons FE , Millar DD
Published: May 2011

A study has been made of the decay of a hydrogen plasma of ion density ~3���1015 cm?3 and temperature ~104�K. Details are presented of the experimental methods used to determine density and temperature distributions in the decaying plasma. The plasma decays by three-body recombination mainly and the experimental values of the recombination coefficient agree with those expected for a plasma opaque to Lyman radiation.
The Behaviour of Free and Attached Electrons in Oxygen
Authors: Rees JA
Published: May 2011

The behaviour in oxygen of swarms of electrons having mean energies of up to 2 eV has been studied. Confirmation of the occurrence in oxygen of a three-body attachment process has been obtained, and the attachment coefficient has been measured for 0.04 < E/p < 6 V cm?1 torr?1. Values of the Townsend energy factor k1 have also been obtained over the same range of values of E/p. It was observed that at least three species of negative ions were formed either directly by the electron attachment processes or through secondary collisions between these primary ions and the gas molecules. The mobilities of the various ion species were determined over the range 0�<�E/p�=�20. The ions were found to have zero-field mobilities of 3.01 �0.04, 2.52���0.04, and 2.39���0.04�cm2 V?1 s?1. The results obtained for the ion mobilities, the attachment coefficient, and the Townsend energy factor have been compared with those obtained in other investigations.
Extended Radio Sources. II.
Authors: Scheuer PAG
Published: May 2011

Detailed observations of "extended radio sources" were reported in a previous communication. Some of these sources are probably irregularities in the galactic radio emission, but at high galactic latitudes the typical extended source consists of a group of sources of small angular diameter.
Some Observations at 6 cm Wavelength with the Australian 210?FT Radio Telescope
Authors: Broten NW , Cooper BFC , Gardner FF , Minnett HC , Price RM , Tonking FG , Yabsley DE
Published: May 2011

Recent research in radio astronomy has shown the desirability of making observations at shorter and shorter wavelengths. Although designed originally for operation at a wavelength of 21 cm, the Australian 210-ft telescope has given satisfactory performances at 11 cm, and operation at still shorter wavelengths appeared possible (Bowen and Minnett 1963).
A Distant HII Region In The Galaxy
Authors: Akabane K , Kerr FJ
Published: May 2011

It has long been realized that 21 cm absorption studies can provide information about the distance of unidentified radio sources. When the radiation from a continuum source is absorbed by neutral hydrogen clouds in the foreground, an observation of the radial velocity range over which the absorption occurs indicates the position of the source in relation to the various hydrogen features along the line of sight. Whenever absorption effects can be seen, we can immediately tell whether the source concerned is galactic or extragalactic; if it is galactic, we can then place limits on its distance.
A Note on a Soluble Three?Body Problem
Authors: Delves LM
Published: May 2011

A class of soluble three-body systems suggested by Pluvinage is studied. The Hamiltonian Ho of these systems is not Hermitian, and the energy spectrum contains a continuum of bound states. The use of H 0 as a reference Hamiltonian in calculations of the helium atom ground state, as suggested by Pluvinage and Walsh, is discussed in the light of these results.
A Transmission Electron Microscope Study of Amethyst and Citrine
Authors: McLaren AC , Phakey PP
Published: May 2011

Thin crystals of amethyst and citrine were examined by transmission elflf'troJl microscopy. It was found that all crystals became damaged during observflti"ll. The diffraction contrast from the damage centres indicated that these were RmfLll amorphous regions. Electron spin resonance observations of these crystals show that the amorphous regions are associated with Fe3+ ions; the damage centres provide, therefore, a measure of the distribution of this impurity in the crystals. Brazil twin boundaries, generally of the order of 1000 A apart, were observed directly. Radiation damage occurred preferentially at the twin boundaries suggesting that there was a concentration of impurities along them. The relevance of these observations to the optical properties of the crystals is discussed briefly.
Solar Radio Bursts of Spectral Type V
Authors: Late AA Weiss The , Stewart RT
Published: May 2011

The properties of the metre-wave type V burst have been-observed by interferometry in the frequency range 40-70 Mc/s, and by dynamic spectroscopy in the frequency range 5-210 Mc/s. Our investigations cover positions, movements, and angular sizes of the sources, and the spectrum and polarization of the emission.
A Preliminary Radio Survey of Planetary Nebulae South of Declination 24 Degrees
Authors: Slee OB , Orchiston DW
Published: May 2011

This paper presents the preliminary results of a survey intended to measure the radio emission of about 70 of the brighter planetary nebulae accessible to the 64 m reflector operated by the Division of Radio physics, CSIRO, at Parkes, N.S.W.
Electrical Breakdown in Polycrystalline Sodium Chloride at 350°C
Authors: Butler LA , Hanscomb JR
Published: May 2011

Previous work (cf. Hanscomb 1962) provided strong evidence that in single crystals of sodium chloride, the mechanism of electrical breakdown is "thermal" at 350�C under conditions in which the specimens were subjected to linearly rising fields resulting in breakdown in the time range 3�5 ms-lO s. The thermal mechanism invoked in that study attributed breakdown to Joule heating from ionic current. No evidence of an electronic contribution to the pre-breakdown current with a consequent "intrinsic" type mechanism of breakdown was found.
Pre-breakdown Ionization in Molecular Nitrogen in E x B Fields
Authors: Bagnall FT , Haydon SC
Published: May 2011

Pre-breakdown ionization measurements in molecular nitrogen are examined to establish whether the influence of a transverse magnetic field is equivalent to an increase in the gas pressure from p to Pe = p(l+w2/v2 )<, where w is the electron cyclotron frequency, and v is a constant, effective, electron-molecule collision frequency. When the value of E/Pe lies within the range 150 < E/Pe < 250 V cm-1 torr-I, v has a constant value equal to 8�3 X 10�p s-" but when E/Pe < 150, vip must decrease with decreasing E/Pe for satisfactory agreement to be maintained. The possibility of extending the concept to account for the changes in secondary ionization and the breakdown potential in nitrogen are also discussed.
Gross Discontinuities in the Magnetization of Type II Superconductors
Authors: Carden PO
Published: May 2011

Continuous records of magnetization as functions of field strength have been obtained for specimens of type II superconductors. The records show gross discontinuities which are attributed to an instability mechanism involving macroscopic induced currents. The supposed mechanism is described and certain theoretical redictions are shown to agree reasonably with the observations.
Elastic and Electromagnetic Proton Interactions at 3 TeV
Authors: McCusker CBA , Peak LS , Woolcott RLS
Published: May 2011

In the present paper we present the results of a line scan, in nuclear emulsion, of protons of average energy 3 TeV. No elastic scatters were detected in the scanned length of 594 cm. We calculate the probability of detecting an elastic scatter in emulsion, and hence that the proton-proton elastic cross section at 3 TeV is :$ 5 mbn.
Energy and Dispersion in Electromagnetic Systems
Authors: Smith WE
Published: May 2011

The total average electromagnetic energy of a loss-free system is expressed in terms of the frequency dependence of the fields on an arbitrary mathematical surface enclosing the system. By introducing scattering, admittance, and impedance matrices the surface integral is reduced and the energy written as quadratic forms involving the frequency derivatives of these matrices. The arguments are of sufficient generality to apply in the presence of inhomogeneous, dispersive, and anisotropic or gyrotropic media. The requirement that the total energy be positive leads to important restrictions on the frequency dependence of the parameter matrices. The application to extensions of Foster's reactance theorem is discussed.
Models of Massive Stars in Homologous Gravitational Contraction
Authors: Meggitt SMA
Published: May 2011

Nine models of homologously contracting, uniform composition stars have been constructed for p,2M/Mo in the range 10-80. Apart from the two smallest models, all models have convective cores, the size of core increasing with the mass. The rate of contraction increases with mass up to p,2M/Mo = 32 and decreases thereafter. One set of models covers all compositions.
Vector Tetrad in Cosmological Red Shift
Authors: Gehlot GL , Durgapal MC
Published: May 2011

The tetrad formalism is applied to certain cosmological models and it is found that the vector 0. has the time component associated with Hubble's expansion.
Backscatter of 16 Mc/s Radio Waves From Land and Sea
Authors: Steele JG
Published: May 2011

Relative backscatter coefficients for 16 Mc/s backscatter from land and sea at elevation angles between 5 and 30� were obtained using a large ground-based sounder at Brisbane. For both land and sea, as the angle of elevation decreases, the backscatter coefficient at first increases smoothly and then decreases suddenly at a certain angle which has been called the knee angle. This angle is about 13� for land, and smaller for sea. For a given angle of elevation above 13�, backscatter from sea is about 10 dB stronger than from land.
A New Kinetic Energy Correction for Capillary Tube Viscometers
Authors: Tanner RI
Published: May 2011

The work of Caw and Wylie (1961) on viscometers with special capillary tubes of slowly varying radius has enabled the usual kinetic energy corrections to be reduced to a very small fraction of those with abrupt-ended capillaries. Thus one of the uncertainties in the use of such tubes is eliminated; also, the remaining small effect is rendered amenable to calculation (Tanner and Linnett 1965). It has been shown theoretically that the relation between viscosity and flow time is expected to be of the form
Precision Measurements of the Townsend Energy Ratio for Electron Swarms in Highly Uniform Electric Fields
Authors: Crompton RW , Elford MT , Gascoigne J
Published: May 2011

A detailed account is given of the solution to the problems associated with the use of the Townsend–Huxley method of measuring the ratio of drift speed to diffusion coefficient for very low energy electron swarms. The elimination of radial components of the electric field within the diffusion chamber is shown to be the major experimental problem, especially in the case of the comparatively weak electric fields which must be used for some of the measurements in the near� thermal region. The experimental techniques and procedures, which are described in some detail, enable measurements to be made in this region with an accuracy comparable to that which has been achieved at higher electron energies.
Some Experimental Observations of the Attenuation of Alfven Waves in a Laboratory Plasma
Authors: Brown IG
Published: May 2011

An experiment is described in which the velocity and attenuation of torsional, azimuthally symmetric, hydromagnetic waves are measured in a hydrogenous plasma, from low frequencies where ion-neutral collisions are unimportant to the wave damping, to frequencies where such collisions profoundly affect the damping. A theory including both ion-electron and ion-neutral collisions is outlined, and the attenuation results are compared with the theoretical values. An estimate is made, from the frequency dependence of the attenuation, of the hydrogen ion-atom collision cross section for momentum transfer.
Diffusion of Heat From a Sphere to a Surrounding Medium
Authors: Brown A
Published: May 2011

In a recent paper, Philip (1964) discussed a heat flow problem in which, as an idealization, spherical symmetry is assumed and the medium is regarded as composite, with a spherical core of one material embedded in a larger mass of a second material. One application in mind was to laccoliths, where an intrusion of igneous rock in sedimentary material can produce dome-shaped bulging at the surface. The idea of treating this as a problem involving spherical symmetry was put forward by Lovering (1935), who gave a solution for the case where the core and its surroundings are taken as uniform. In a subsequent paper, Lovering (1936) considered in more detail what variations in the thermal conductivity and diffusivity are to be expected. From the figures he quotes, a composite model should give a better approximation, though remaining a considerable simplification of the physical problem.
On Bowen's Hypothesis
Authors: Visvanathan TR
Published: May 2011

Bowen (1953) examined daily rainfall at Sydney for January for the years 1859-1940, and found exceptional peaks to occur on the 12th and 22nd days of that month. He extended his investigations to other months and other stations, and concluded that there is a marked tendency for heavy falls of rain to occur on certain dates rather than on others and the pattern to be repeated year after year. He argued that if the feature is noticed in rainfall at a large number of stations over the globe the influence should be extraterrestrial. He put forward the now well-known hypothesis that on some calendar dates the Earth crosses a meteoric stream, and the meteoric dust entering the top of the atmosphere reaches the troposphere about 30 days later, to induce heavy rainfall, the influx of meteoric dust being supposed to provide the necessary condensation nuclei. He further strengthened his hypothesis by showing that such other occurrences as concentration of freezing nuclei counts, cirrus clouds, noctilucent clouds, and the dates on which snow first covered the ground at Tokyo all showed a tendency for maxima to fall on the preferred dates of singularity in a in all.
A Theoretical Analysis of the Townsend - Huxley Swarm Technique for Electrons
Authors: Hurst CA , Liley BS
Published: May 2011

The Townsend–Huxley swarm technique for electrons is analysed in detail. Particular emphasis is placed on boundary conditions, and those conditions appropriate to the Huxley–Crompton empirical relationship are derived and explained. Secondary emission at the electrodes due to both positive ion and photon bombardment is also taken into account. The principal result is an integral expression for the current ratio received at the circumferentially split anode. From this may be deduced the energy factor kl And the secondary emission coefficients. It is shown that it is possible to distinguish between positive ion and photon secondary emission and to determine the associated coefficients simultaneously in the stationary state. Highly accurate conditions for electrical breakdown are also obtained, secondary emission at the anode being taken into account.
The Diffusion and Attachment of Electrons in Water Vapour
Authors: Crompton RW , Rees JA , Jory RL
Published: May 2011

The energy ratio and attachment coefficient for electrons in water vapour have been determined in the range 20 E/p −l torr−l. The results for the attachment coefficient are in general agreement with other recent determinations, but those for the energy ratio differ significantly from the results of Bailey and Duncanson. The use of these new data, in conjunction with values of the drift velocity determined by Pack, Voshall, and Phelps, is shown to remove the serious discrepancy which previously existed between the results of single-collision and swarm experiments.
A Study of the Decimetric Emission and Polarization of Centaurus A
Authors: Cooper BFC , Price RM , Cole DJ
Published: May 2011

The results of a study of Centaurus A in the wavelength range 6-74 cm are presented. From observations at 11, 21, and 31 cm the intrinsic polarization and Faraday rotation have been determined for much of the source.
The 16O(g, p0)15N Cross Section Between 14 and 16 MeV
Authors: Stewart RJJ , Cannington PH , Spicer BM
Published: May 2011

This paper reports an investigation of the 90� differential cross section for the 160(Y,PO)15N reaction from 14 to 16 MeV.
On Wind-induced Flows in Closed Channels
Authors: Johnson CHJ
Published: May 2011

The mean velocity and shear-stress profiles for a wind-induced flow in a closed channel with constant surface slope are first derived using a turbulent viscosity constructed by dimensional arguments. Using a perturbation analysis based on the fact that the surface slope is small, these results are extended to the case where the surface slope, and hence flow conditions generally, are allowed to vary in a downwind direction. Explicit results are obtained for the velocity and shear-stress profiles and also for the surface slope as a function of distance downwind. The results agree quite well with experiment, although better agreement would probably be obtained by using a more elaborate turbulent iscosity_
Dielectric Saturation in Ionic Crystals. I. Rigid Ion Model
Authors: Oitmaa J
Published: May 2011

The higher-order term in the static dielectric constant of an ionic crystal, which is proportional to the square of the applied field, is calculated using a rigid ion model. An explicit expression is obtained for this term, involving anharmonic coefficients, and is evaluated for NaCI.
A Study of the Magneto?Kerr and Other Effects at a Plasma Surface
Authors: Robinson LC
Published: May 2011

The role of microwave reflection observations and particularly the magneto. microwave Kerr effect in the study of plasma surface phenomena is discussed. The method makes possible the absolute measurement of high electron surface densities in a density region not readily accessible to other experimental techniques, and it gives an indication of the collision frequency for momentum transfer.
Proper Ties of a Laboratory Plasma Prepared with Combined Transverse and Longitudinal Currents
Authors: Brown IG , Lehane JA , Potter IC , Watson-Munro CN
Published: May 2011

For some laboratory plasma physics experiments it is necessary to have a plasma of high fractional ionization that is confined in a relatively low magnetic field and for which the charged particle densities and kinetic temperatures do not change too rapidly in space or time. It has been found that a plasma prepared by a "hybrid" method with ionizing currents, both transverse and parallel to the steady magnetic field, has distinct advantages for such experiments.
Night-time Sferic Propagation at Frequencies Below 10 KHz
Authors: Lynn KJW , Crouchley J
Published: May 2011

Results of a study at Brisbane of individual night-time sferics of known origin are described. A propagation attenuation minimum was observed in the 3-6 kHz range. The geographic distribution of sferic types was also examined. Apparent propagation asynunetries were observed, since sferics were detected at greater ranges to the west than to the east at 10 kHz, whilst the number of tweek-sferics arising from the east was about four times that arising from the west. Comparison with European studies suggest that these asymmetries are general. These results are then " interpreted in terms of an ionospheric reflection cgefficient which is a function of the effective angle of incidence of the wave on the ionosphere and of orientation with respect to the Earth's magnetic field within the ionosphere.
Short Communications Crystal Field Theory and Magnetic Groups: Spin?Orbit Coupling
Authors: Cracknell AP
Published: May 2011

Some initial work has recently been done (Cracknell 1966a) on the applicationof the theory of the corepresentations of non-unitary groups to the consideration ofthe splitting of atomic energy levels in a crystalline field possessing the mmetryof one of the magnetic point groups, or Shubnikov point groups. In that work onlythe situation of a strong rystalline field in the complete absence of spin
The Angular Distribution of Atoms Sputtered from Monocrystalline Gold
Authors: Chapman GE , Kelly JC
Published: May 2011

The angular distribution of atoms sputtered from metal single crystals has been used to study atom ejection processes. By analysing this distribution into the sum of a Gaussian and a cosine contribution it is shown that the isotropic background can be removed and considerably improved agreement obtained between theory and experiment. This is applied to the temperature variation of the width of Wehner spots. New experimental results are presented for gold sputtered by 10 keY argon ions over a wide range of temperatures.
Interference Between Levels in Nuclear Reactions
Authors: Barker FC
Published: May 2011

In this note we consider the cross section for a nuclear reaction in which one of the product nuclei is unstable, with two or more levels contributing to its decay. Previously a formula had been derived from R-matrix theory for the case where contributions come from only a single level of the nucleus with a given spin and parity.
Electron Binding Energies in Transition Metals
Authors: Lynch MJ , Swan JB
Published: May 2011

It has been suggested (Fahlman et al. 1965) that electron binding energies measured by X-ray methods may in some cases be in error by as much as 50%. The electron pectroscopic method (e.g. Hagstrom 1964; Siegbahn 1965) is claimed to be capable of yielding more accurate values of electron binding energies, and many measurements have been made using this technique, though the majority have been of the binding energies in the inner electronic shells.
A Theory of Solar Type IV Emission on Centimetre and Decimetre Wavelengths
Authors: Yip WK
Published: May 2011

Assuming models for electron density and magnetic field configuration in the lower solar active corona, it is proposed that type IV bursts on centimeter and decimetre wavelengths are the results of cyclotron radiation from helical electron streams. In order to explain the observed polarization features and spectral variabilities, the characteristics of cyclotron radiation from electron streams and the propagation of electromagnetic waves in the active corona are investigated. Adopting the current model for flare evolution, most of the properties of type IV bursts on centimetre and decimetre wavelengths are well interpreted by the present theory.
Short Communications: A Method of Obtaining the Mean Electron Collision Frequencies in the F2 Layer from Cosmic Noise Absorption Studies
Authors: Krishnamurthi M , Subrahmanya Sarma SBS
Published: May 2011

In the previous paper (pp. 455-62 of the present issue) the authors have shown that the total ionospheric absorption of cosmic noise at 28�6 MHz can be expressed as a sum of three contributions: from the F2 layer (including topside ionosphere), from the D and E layers, and from abnormal phenomena such as spread-F; and can be given by the expression
The Drift Velocity of Potassium Ions in Hydrogen at 293°K
Authors: Elford MT
Published: May 2011

Although there exists a large body of data for the drift velocity of positive ions in gases (Loeb 1955; McDaniel 1964), some of the data are conflicting or ambiguous due to uncertainty concerning the identity of the ion being studied (Dalgarno, McDowell, and Williams 1958; Davies et al. 1966). This ambiguity isparticularly serious in the case of atomic or molecular ions moving in the parent gas, since ion-molecule reactions may occur in the ion source or within the drift chamber. The necessity for simultaneous drift velocity measurements and ion identification has led a number of workers (e.g. Edelson and McAffee 1964; Keller, Martin, and McDaniel 1965; Madson, Oskam, and Chanin 1965; Saporoschenko 1965) to design experiments in which such identification is possible. In these experiments the gas pressure in the drift chamber is of the order of a few torr while that in the mass spectrometer is usually less than 10-5 torr.
Nuclear Level Densities in Intermediate and Heavy Nuclei
Authors: Cook JL , Ferguson H , de L Musgrove AR
Published: May 2011

The level densities of intermediate and heavy nuclei have been fitted to the free gas model formula with some improvement over previous fits. The predictions of tho model regarding cross section behaviour have been tested and found to lead to anomalous behaviour of the partial widths for incident neutron energies above 1�5 MeV.
The Semiclassical Model of Direct Reactions
Authors: Robertson I
Published: May 2011

The semiclassical model of direct reactions is reviewed and its predictions are presented for a reaction that exhibits the phenomenon of backward peaking, following the work of Pearson. The curve a(1800) against energy is fitted quite closely and the shape of the curve has a simple explanation in terms of the bound state radial wave functions.
Effects of Air Compression Between Parallel Plates in Interferometric and Capacitive Displacement Transducers
Authors: Goldberg JL
Published: May 2011

When one of two adjacent surfaces of a displacement transducer, such as a parallel plate capacitor or an optical interferometer, is moved towards the other the compression of air between the surfaces alters the dielectric constant and the refractive index of the air during the motion. In making a precise measurement of a transient displacement with one or other transducer not in vacuo, a correction to the measured value of capacitance or path difference may be necessary.
Space Charge Effects in the Townsend?Huxley Swarm Technique
Authors: Liley BS
Published: May 2011

An analytical treatment of space charge effects in the Townsend-Huxley swarm technique is given. The general case of a mixed swarm of equally charged ions and electrons drifting through a gas in which attachment is possible is considered. The case of a pure electron or pure ion swarm is treated as a particular case of the general one. The main result is an expression for R(r,z), this being the ratio of the current collected by a disk of radius r, in the plane z = z, to the total swarm current. This ratio is determined as an explicit function of DIp-, the total current, the electron (or ion) current, and the attachment coefficient. It is shown that space charge effects can be of importance for large currents, low E Ip, and low gas temperatures. Moreover, in practice such effects are only likely to be of interest in thermal swarms.
Frequency Splitting of Solar Radio Bursts
Authors: Ellis GRA , McCulloch PM
Published: May 2011

Solar radio bursts showing frequency splitting have been observed regularly below 60 MHz. The bursts have a duration of 1-2 sec and a frequency interval between their elements of 0�1-1�0 MHz. Their wave frequency generally decreases with time at about O� 1 MHz/sec. The bursts may occur either in isolation, in chains associated with type III bursts, or in large numbers during noise storms. Triple splitting is observed in about 10% of the bursts. The properties of the bursts are not inconsistent with those expected from magnetic splitting of the radiation.
A Survey of the Southern Sky at 85 MHz
Authors: Yates KW , Wielebinski R , Landecker TL
Published: May 2011

A survey at 85 MHz is presented of the sky south of declination 0 = _20�,and of the northern galactic spur region to 0 = +20�. The survey was made withthe 210 ft telescope at Parkes, New South Wales. At this frequency the observedbeamwidth was 3.5� by 3� 8� to half-power points. The radiation characteristics ofthe survey aerial and of scaled aerial models were studied to enable corrections to bemade for radiation received by the aerial from regions outside the main beam.Absolute beam temperatures derived from the observed aerial temperatures had anr.m.s. accuracy of better than 7%.
Inelastic Scattering of 3He from 6Li, 7Li, 10B, 19F, and 27Al at 10 MeV
Authors: Coop KL , Poate JM , Titterton EW
Published: May 2011

There have been no reports in the literature of 3He inelastic scattering below some 15 MeV bombarding energy. Because such inelastic scattering can provide useful information on both the compound and residual nuclei involved, it was decided to carry out some preliminary measurements on representative light nuclei to check the feasibility of undertaking a full-scale investigation. This note presents the results of these easurements.
The Influence of Diffusion on the Townsend Discharge in a Uniform Electric Field
Authors: Burch DS , Huxley LGH
Published: May 2011

An analysis is presented to elucidate the role of diffusion in a Townsend discharge between plane parallel electrodes. Spatial independence of the electron energy distribution function is postulated, and the development proceeds by solution of the appropriate continuity equations. It is shown that experiment may be expected to verify Townsend's law in all but extreme cases, but that diffusion corrections must be applied if measured values of the primary ionization coefficient exT are to be used for etermination of quantities such as the ionizing collision frequency. Further, Paschen's law is emonstrated to be unaffected by effects resulting from diffusion.
Structure of Polytropes in Magnetostatic Equilibrium
Authors: Van Der Borght R
Published: May 2011

This paper investigates the structure of a poly trope in which a magnetic field, having both poloidal and toroidal components, is present. The influence of the toroidal component on the oblateness of the configuration is also considered.
Angular Velocity Distribution in Rotating Massive Stars
Authors: Legg MPC
Published: May 2011

The angular velocity distribution in rotating massive stars with uniform composition and opacity due to electron scattering is calculated on the assumption that meridional circulation is neglible. The effects of radiation pressure are taken into account in the determination of the differential rotation and the angularvelocity is assumed to be ndependent of latitude.
On a Godel-type Nonstatic Cosmological Solution for Matter in an Electromagnetic Field
Authors: Raval HM
Published: May 2011

Some solutions of the Einstein-Maxwell equations for gravitational and electromagnetic fields against the background of a rotating and either a stationary or an expanding cosmological model have been obtained. The details of one of these solutions have been given. The solution describes a cosmological model with rotation and shear. The model is initially stationary and then expanding. It is filled with anisotropic fluid and is pervaded by the electromagnetic field, the net charge density being zero.
The Radiant Output of Grenade Glow Clouds in the Lower Thermosphere
Authors: Johnson ER , Lloyd KH , Low CH , Sheppard LM
Published: May 2011

Records of the behaviour of aluminized grenade glow clouds at twilight and at night were obtained using cameras and photometers. From these records the radiance, radiant p~wer, and radiant energy have been deduced for the altitude range 100-200 km. The twilight observations show that the absorption cross section of aluminium monoxide is about 3 X lO-14 cm2? From the night-time results it is concluded that the glow probably arises from a chemiluminescent reaction with atomic oxygen. A set of reactions consistent with the observations above 120 km altitude is
Source Flux Densities at 153 MHz
Authors: Hamilton PA , Haynes RF
Published: May 2011

This paper gives fiux density measurements of 312 sources at 153 MHz obtained from a general continuum survey made with the 210 ft radio telescope of the Australian National Radio Astronomy Observatory, Parkes, N.S.W. The beamwidth of the telescope at this frequency is 2� 18�. Some discussion of results for spectra is given and a comparison is made with other measurements of the same sources.
Radio Emission from Clusters of Galaxies
Authors: Tovmassian HM , Moiseev IG
Published: May 2011

From Abell's (1958) list of clusters of galaxies, 137 clusters of distance group 5 were observed at 1410 MHz with the 210 ft radio telescope of the Australian National Radio Astronomy Observatory at Parkes. The detected radio sources were further confirmed hy observations at 2650 MHz with the same telescope and at 408 MHz with the east-west arm of the Mills Cross at the Molonglo Radio Astronomical Observatory. A total of 25 radio sources was detected within 5' arc of the centres of corresponding clusters of galaxies, while the mathematical expectation of the number of random coincidences with clusters is about two or three
Observations of Some Radio Sources Previously Identified with Clusters of Galaxies
Authors: Tovmassian HM , Moiseev IG
Published: May 2011

The positions of 33 radio sources previously identified with distant clusters of galaxies were remeasured more accurately to check the identifications. Observations were made at 1410 and 2650 MHz with the 210 ft radio telescope of the Australian National Radio Astronomy Observatory at Parkes, and at 408 MHz with the east-west arm of the Mills Cross at the Molonglo Radio Astronomical Observatory of the University of Sydney. It was found that 21 sources are situated within 5 min of arc of the centres of the corresponding clusters.
The Measurement of Electron Drift Velocities
Authors: Blevin HA , Hasan MZ
Published: May 2011

Several methods (Loeb 1955; Breare and von Engel 1964; Raether 1964) have been devised to measure the drift velocity W of electrons moving under the influence of an electric field E through a gas at pressure p. The most accurate method is that of Bradbury and Nielsen (1936) (see also Lowke 1963), but for reasons discussed below this technique has been limited to low values of E/p. We have found that the useful range of this method can be greatly extended by some modification to the conventional form of the apparatus.
The Collision Broadening of Spectral Lines
Authors: Parsons RW , Metchnik VI , Dyne RJ
Published: May 2011

The shape of a collision-broadened spectral line depends on the assumptions made about the collision processes involved. If the collision cross section varies inversely as the relative speed of the colliding molecules, the half-width to the half-power points and to the points of steepest slope should be 1/27T1' and 1/(2";3)7T1' respectively, where l' is the mean interval between line-broadening collisions. It is shown that, in a gas of "hard-sphere" molecules, the shape of the line is modified and the above half-widths are reduced by' 6�4 and 9�7% respectively. While it is not suggested that gas molecules behave entirely as hard spheres, it is suggested that some deviations from the Van Vleck-Weisskopf-Lorentz shape may occur, and that it may be possible to detect these deviations experimentally