bluuebunny/crossref_metadata_2025 huggingface dataset:
The Decimetre Wavelength Radiation Associated With Type IV Solar Radio Bursts
Authors: Krishnan T , Mullaly RF
Published: May 2011

Results are presented of high-resolution studies made with the Christiansen grating interferometer of eight 21-cm burst events known to coincide with type IV metrewavelength events. The decimetre wavelength sources remained in the lower corona in regions widely separated from the sources of simultaneous metre-wavelength emission. Physical measurements of the eight decimetre sources are also given: brightness temperatures (10' to 10� OK), apparent diameters (2 to 5' of arc) and heights (approximately 50,000 km above photosphere).
Ray Paths in Inhomogeneous Anisotropic Media
Authors: Mullaly RF
Published: May 2011

The paths of rays in inhomogeneous anisotropic media are studied, starting from Fermat's Principle of Stationary Time. The media considered have a refractive index which depends on the angle between the direction of propagation and an axis of symmetry in the medium, and on several scalar parameters; both these and the direction of the axis are functions of position. Expressions are developed for the curvature of a ray path and are applied to (a) radio rays in an ionized medium pervaded by a non-uniform magnetic field and (b) acoustical rays in a moving fluid.
The Ray Paths of Whistling Atmospherics: Differential Geometry
Authors: Mullaly F
Published: May 2011

Expressions are developed on the basis of geometrical optics for the curvature of a whistler ray path in terms of the gradients of electron density, magnetic field strength, and field direction, the analysis being restricted for simplicity to paths which are plane curves. It is shown that there is in general no tendency for the rays to follow the lines of force closely unless the wave-normal is very nearly at right angles to the direction of the ray.
Velocities of Shock Fronts in Solar Corona Generating Type II Radio Bursts at Metre Wavelengths
Authors: Krishnamurthi M , Sivarama Sastry G , Seshagiri Rao T
Published: May 2011

At the time of intense solar flares, various types of enhanced radio emission from the Sun have been observed. Using such techniques as the swept frequency technique first developed by Wild and his associates, these enhanced emissions have been classified into five types. Of particular interest to radio astronomy at metre wavelengths is the slow drift type II bursts. A comprehensive study of these bursts has been made by Roberts (1959). It is now supposed that at the start of a flare an explosion occurs in the lower regions of the solar atmosphere ejecting a column of gas which travels radially outward from the region of the flare. This column of gas is bounded by a shock front which moves forward relative to this gas. This shock front is assumed to excite plasma oscillations in the solar corona giving rise to type II radiation. Velocities of these shock fronts have been determined by various workers.
Carbon?Carbon Elastic Scattering
Authors: Bunyan PJ
Published: May 2011

Optical model analyses of elastic scattering of heavy ions have been carried out by Porter (1958) for nitrogen-nitrogen, and a preliminary study of the carbonnitrogen system has been made by Bassel, Melkanoff, and Drisko (Halbert, Hunting, and Zucker 1960). These analyses have shown that the optical model is capable of predicting, to a higher accuracy than the semiclassical models, the heavy ion elastic angular distributions.
Scattering of Alpha-particles by a Vibrational Nucleus
Authors: Tassie LJ
Published: May 2011

The elastic and inelastic scattering of cx-particles by a vibrational nucleus is calculated using plane-wave Born approximation. The excitation of both single-phonon and twophonon states is considered. The effect of the diffuseness of the nuclear surface is included. The result for elastic scattering and the excitation of the single-phonon 2+ and 3- states is in good agreement with experiment for .oNi. The approximations used are discussed, and it is suggested that excitation of 0+, 1-, and 5- states should provide the best experimental test of the theory of two-phonon excitation of nuclei. The energies of the vibrational states are also considered.
Floating Multiple Probe Systems for Plasma Measurements
Authors: Burrows KM
Published: May 2011

A new analysis of the current voltage characteristic of a floating double probe system is given, showing that the electron temperature must be estimated from measurements at the point of inflection of the characteristic if positive ion movement contributes to the probe circuit current. Temperature measurements will still be in error if the rates of variation of positive ion current to the two probes are not closely similar as the potential difference between them is varied. An alternative experimental technique is described which will yield correct temperature estimates in such circumstances, and is simpler and less perturbing to the plasma than the floating triple probe method.
Limiting Precision in a Scanning Optical Interferometer
Authors: Hill RM , Bruce CF
Published: May 2011

An examination of the limiting precision with which a scanning optical interferometer can be pointed on a fringe peak is described. The interferometer uses photoelectric detection and it is shown that the principal noise sources limiting the accuracy of detection are the shot noise in the vacuum photocell and the photon noise from the light source.
Joule Heating of the Upper Atmosphere
Authors: Cole KD
Published: May 2011

The joule heating and motion of uniform ionized gas is discussed, on the assumption that uniform electric and mechanical force fields are orthogonal to the (homogeneous) magnetic field.
Correlation Between Sporadic E Ionization and the Strength of the Horizontal Component of the Earth's Magnetic Field
Authors: Wilkie JR , McNicol RWE
Published: May 2011

By analysis of geomagnetic and ionospheric data recorded at Brisbane it has been found that the horizontal component of the Earth's magnetic field is decreased in strength by a few gammas during the appearance on ionograms of short-duration echoes, normally interpreted as coming from isolated patches of Es ionization.
Distribution of Auroras in the Southern Hemisphere. II. Nightly Probability of Overhead Aurora
Authors: Bond FR , Jacka F
Published: May 2011

The probability P of overhead occurrence of aurora during a night is estimated for 22 southern hemisphere stations during the I.G.Y. The distribution of probability of occurrence is represented in terms of three measures of colatitude: 81 is defined in terms of the eccentric dipole representation of the geomagnetic field; 82 is defined in terms of projections from circles in the equatorial plane, along the geomagnetic lines of force, onto the Earth; 83 is defined in terms of the integral invariant f; (I-F IF m)!dl of charged particle motion in the geomagnetic field.
Source Functions for Diffusion in Uniform Shear Flow
Authors: Elrick DE
Published: May 2011

The problem of molecular diffusion in a fluid simultaneously undergoing shear flow is analysed for the simple case of uniform shear. Solutions for instantaneous point and line sources are obtained using Fourier transform methods and the results are presented in some detail. The solutions also describe the diffusion of heat from an instantaneously heated source in a fluid undergoing a similar shear pattern.
The Cold Cathode Arc
Authors: Eather RH
Published: May 2011

Many theories have been proposed in the last 15 years to explain the observed high current densities associated with the cold cathode arcs. All of these theories are somewhat inadequate in themselves, but a combination of some of the more recent theories gives a satisfactory explanation of these high current densities.
Motions in the Chromosphere Near Sunspots
Authors: Beckers JM
Published: May 2011

The Evershed velocities in the chromosphere have been studied from Hex filtergrams. Inward motions are found in the region extending from the outer boundary of the penumbra out to two sunspot radii; the moving matter is not evenly distributed around the spot but flows in along channels. These have lifetimes of about 9 hr, very long as� compared with the time of passage at inflow velocities of 45 km/sec. The velocity vector makes an angle of about 13� with the solar surface, suggesting that the matter is constrained to flow along lines of magnetic force. If so, the high velocities of inflow appear to be purely gravitational.
Cyclotron Radiation From Jupiter
Authors: Ellis GRA
Published: May 2011

Cyclotron radiation from bunches of electrons trapped in ,a planetary magnetic field is discussed as a possible cause of the decametric wavelength radio emissions of Jupiter. By assuming the existence of an exospheric ionized medium, similar to that of the Earth, many of the observed properties of the radiation may be obtained by this process.
A Radio Survey of the Southern Milky Way at a Frequency of 1440 Mc/s. I. The Isophotes and the Discrete Sources
Authors: Mathewson DS , Healey JR , Rome JM
Published: May 2011

The 1440 Mc/s isophotes of the Southern Milky Way are presented which were obtained with an aerial beam 50' of arc at half-power points. The positions and intensities of the discrete sources resolved from the background emission are listed together with their spectral characteristics determined by comparison with the 85 -5 Mc/s Mills-Cross survey. Of 74 sources, 54 are found to have spectral indices consistent with the assumption that they radiate thermally_ Twelve new identifications of these thermal radio sources haye been made with emission nebulae by comparison with the Stromlo Atlas of Hex emission. The remaining twenty sources have nonthermal spectral indices and no new optical identifications have been made_ The continuum background emission from the galactic disk is discussed in a second paper.
A Radio Survey of the Southern Milky Way at a Frequency of 1440 Mc/s. II. The Continuum Emission from the Galactic Disk
Authors: Mathewson DS , Healey JR , Rome JM
Published: May 2011

The 1440 Mcls survey (Part I of this series) has been used in conjunction with the 85�5Mc/s survey of Hill, Slee, and Mills (1958) to delineate the distribution of the thermal and nonthermal radiation from the disk component of the Southern Milky Way and so complete an investigation commenced by the Northern Hemisphere observers Westerhout (Leiden) and Large, Mathewson, and Haslam (Jodrell Bank). Results of the analysis show an intense concent,ration of ionized hydrogen in an irregular spiral structure in the inner regions of the Galaxy. From lII=256� to 88�, good agreement was obtained between the longitudes at which concentrations of neutral hydrogen were found to occur from H-line studies and the longitudes at which the ionized hydrogen was concentrated. The steps in the longitude distribution of the 85�5 Mcls radiation which Mills used to delineate the spiral arms of the Galaxy were not all visible in the longitude distribution of the nonthermal component obtained from this present analysis. It is believed that three of Mills's steps are thermal in origin.
Sea-level Momentum Spectra of Muons
Authors: Coates DW , Nash WF
Published: May 2011

The sea-level muon momentum spectrum in t,he range 0'7-30 GeV/c has been measured at Nottingham, England, at zenith angles of 0�,30� W., and 45 oW., based on 1052, 1010, and 1033 particles respectively. Agreement is found at 0� with the results of Owen and Wilson (1955) and disagreement with those of Caro, Parry, and Rathgeber (1951). The same form of disagreement occurs with the results of Moroney and Parry (1954) at 30� obtained using the same instrument as Caro, Parry, and Rathgeber. Within the statistical accuracy of the experi~ent satisfactory agreement is found with the theories based on either single level or extended production of the muons.
Source Corrections to the Sydney Radio Source Survey Catalogue
Authors: Hill ER , Mills BY
Published: May 2011

The primary purpose of this' communication is to report some modifications to two of the three radio source catalogues based on the Mills Cross pencil beam survey of sources at 85�5 Mc/s (Mills, Slee, and Hill 1958, 1960, 1961). These catalogues will subsequently be referred to as MSH.
On the Swarm Method for Determining the Ratio of Electron Drift Velocity to Diffusion Coefficient
Authors: Crompton RW , Jory RL
Published: May 2011

The use of data from swarm experiments for electron energies approaching those corresponding to thermal equilibrium demands results of greater precision than has hitherto been available. In order to examine the possibility of producing such data, the swarm method for detennining W / D has been extensively examined over a range of values of the parameter E / p where the agreement between the results of recent investigations is not good. A number of factors influencing the accuracy of measurements of this type are discussed. The results for hydrogen which are presented are considered to be subject to an error of less than 1 %.
A Study of Whistling Atmospherics. III. Observations at Closely Spaced Stations
Authors: Crouchley J , Duff KJ
Published: May 2011

Whistling atmospherics were recorded simultaneously at four stations with separations of about 150 km during the winter of 1960. Individual whistlers showed the same dispersions at all stations but significant differences in strength were sometimes observed. These features and the diffuseness of the whistlers are consistent with the idea of the energy emerging from the ionosphere through localized regions of size of the order of 100 km or less. A method has been developed of obtaining amplitude-frequency profiles. These were sometimes fairly flat but the less diffuse whistlers tended to show abrupt (up to 100 dB (kc/s)-') changes of amplitude of up to more than 20 dB for frequency ranges of about half a kilocycle per second. Such changes were, on occasions, dissimilar at the four stations.
Resonant Behaviour of an Acoustical Transmission Line
Authors: Pollard HF
Published: May 2011

In the passage of elastic waves through a cylindrical rod, phenomena are exhibited that closely resemble those occurring in an electromagnetic waveguide. Following a discussion of the classical Pochhammer-Chree theory for an infinite cylinder, elastic wave propagation in a finite rod is considered under conditions ~hen the rod may be regarded as analogous to an electrical transmission line. In the case of a resonant system, normal mode analysis provides a simplified treatment and it is shown that the results are in agreement with transmission-line theory. A brief discussion is given regarding the identity of the pulse response of a system and its response to continuous waves.
New Spectrographic Lens System
Authors: Feuerriegel T
Published: May 2011

The performance of a three�prism stellar spectrograph of the Mount Stromlo Observatory is discussed. A new spectrographic objective (relative aperture fl3�5) has been designed for the largest practicable extension of the spectral image field perpendicular to the optical axis-considering stellar spectra in the wavelength region 3900-4900 A to be recorded in good definition. The complete system specifications are indicated and the design of the spectrographic objective is described.
The New South Wales Earthquake of May 22, 1961
Authors: Cooney GH
Published: May 2011

The earthquake of May 21, 1961 is investigated. The finally revised epicenter 1.S 34� 36' S. (geographic)., 150� 24' E., and the adopted origin time 21h 40m 01s (G.M.T.). 'The five near stations with a < 1 � . 5 give a PI velocity of 6� 06 � 0 . 17 km/s, and the �eight stations with 2�<;a<;9� give a Pn velocity of S�OO�O�OS km/s. The distribution of the residuals contains no evidence of appreciable focal depth. Using the PI and Pn phases, a crustal thickness (on the assumption of a uniform crust) of 40 � 5 km is formally indicated.
High Field Polarization Reversals in Liquid Electroded Barium Titanate Crystals
Authors: Taylor GW
Published: May 2011

The study of the polarization reversal in liquid electroded crystals of barium titanate has previously been mainly restricted to switching fields less than 1� 2 k V fcm. This paper studies the reversal in the field range 1� 5-6 kV fcm. For these higher fields, it is concluded, from switching current transients and " static" domain patterns, that the reversal is achieved by a small number of parallel. sided domains expanding radially sidewise at a constant velocity. All the domains appear to begin growing when the field is first applied. The cross-sectional shape of the domains varies from circular at fields greater than 3 kVfcm to square at fields less than 3 kVfcm. The number and distribution of the domain centres is determined by the surface conditions of the crystal, where the electrodes are situated, and not by the applied field.
Solar Decimetre Radio Bursts
Authors: Mullaly RF , Krishnan T
Published: May 2011

High resolution studies (2' of arc beam) were made with the east�west arm of the Christiansen radio interferometer for about 50 21�cm solar burst events during 1958-1961. The burst sources were always closely associated in position with already existing radio plage regions of the Sun's slowly varying decimetre radiation. They had sizes of from 2 to 5' of arc, never exceeded but often approached in size their parent plage region, and showed no major movements during their development. Brightness temperatures ranged up to 2 X 109 OK (mostly between 107 and 108 OK). More bursts were observed near the Sun's centre than near the limb, and more on the western than on the eastern half. There was also a curious "gap" of 30� longitude on the eastern half of the Sun with virtually no burst activity.
Properties of the Lunar Surface as Revealed by Thermal Radiation
Authors: Muncey RW
Published: May 2011

Thermal radiation from the moon has been previously measured by both optical and microwave techniques, and this has led several workers to estimate the thermal properties of the lunar surface. Using the assumption that the thermal properties are proportional to the temperature, the uniform surface corresponding to the observed optical values is calculated. Possible mixed surfaces are also evaluated. These are examined to estimate the likely variation in microwave radiation, and by comparison with observed results it is shown that the most probable surface consists partly of rock or gravel overlain by a thin layer of fine dust, and partly of areas with dust extending to beyond the depth from which the microwave radiation emanates.
The Directions of Auroral Rays
Authors: Cole KD
Published: May 2011

The geometry of the radiation point of an auroral corona is examined. The radiation point of two rays is the antidirection of the point within the Earth at which the rays meet or appear to meet. It is therefore incorrect to identify the radiant point of a corona with local auroral zenith. Their difference in direction is commonly 0.5� of zenith distance. The importance of rays as magnetic disturbance indicators in the height range 100-1000 km is stressed, particularly in view of possible deformations of the magnetosphere whose full effects may not be estimated from groundbased observations of the geomagnetic field.
The Change in Colour of a Silver-Gold Alloy on Plastic Deformation
Authors: Yates EL
Published: May 2011

The colour change when deformed samples of the alloy AgAu are annealed has been confInned and an attempt has been made to measure it in terms of the movement of the spectral absorption edge. It is found that on annealing the absorption edge of a heavily deformed sample moves about 5�4 mp, toward shorter wavelengths. No such effect was observed in the pure metals, silver and gold. It is suggested that the effect may be connected with the presence of short-range order and/or with a migration of silver atoms to the surface in the annealing process.
The Specific Heat of Metals Between 1200°K and 2400°K
Authors: Lowentha GC
Published: May 2011

Specific heat measurements have been made on niobium (from 1471 to 22600K), molybdenum (from 1288 to 2015�K), tantalum (from 1256 to 23000K), and tungsten (from 1267 to 24100K). The experiments were based on a theory first proposed by Corbino in 1911. It is demonstrated that methods based on this theory account for heat losses from the specimen under test to better than 0'5% even at 2400oK. The theory requires a knowledge of the temperature oscillations in thin a.c. heated filaments and this amplitude is here obtained from photoelectric measurements.
The Calibration of Linear Scales by the Method of Hansen-Perard
Authors: Thwaite EG , Leslie RT
Published: May 2011

The classical methods of scale calibration originally formulated by Hansen
(1873) and developed by Perard (1917) and referred to here, after Perard, as the
methods of "simple calibration" and "cross calibration", have an extensive literature
(Judson 1927; Platanov 1941). The rigorous least-squares solution in the linear case
is complicated, however, and the simplified method of Thiesen (1879), known as
"graphical squares" or the "method of means" (Johnson 1923) has generally
been used.e set of equations
The Drift Velocity of Electrons in Hydrogen and Nitrogen
Authors: Lowke JJ
Published: May 2011

Experimental results are given for the drift velocity of electrons in hydrogen and nitrogen at 293�K and 77�6�K over the range 0�001<Elp< 20 V cm-1 mmHg--I. The results were obtained using the method of Bradbury and Nielsen and have in general an accuracy of 1 % at 293�K and 2 % at 77� 6�K. The measurements were made over as wide a range of gas pressures as possible for each value of JiJlp and all results are presented in tabular form. In the final results that are presented corrections have been made for errors due to diffusion. Experiments are also discussed which were designed to investigate the extent of the� existence of errors due to factors such as distortion of the d.c. field from voltages on the shutter wires and the presence of gaseous impurities. It has been shown that measurements of the drift. yelocity are particularly sflDsitive to traces of water vapour as impurity.
A Sky Survey of Neutral Hydrogen at l 21 cm. II. The Detailed Distribution of Low Velocity Gas
Authors: McGee RX , Murray JD , A Milton Janice
Published: May 2011

The distributions of intensity and radial velocity of neutral hydrogen gas of low radial velocity are presented in the form of detailed diagrams of T max., the temperature at the peak of a hydrogen line profile, and of the radial velocity value at the Tmax .
Anomalous VHF Trans-equatorial Ionospheric Propagation Recorded at Townsville
Authors: Carman EH , Gibson-Wilde BC , Conway RJ
Published: May 2011

Since Ferrell (1951) first reported anomalous VHF propagation in equatorial regions, a number of workers have observed the phenomenon during the early afternoon and evening hours, especially the latter. Backscatter experiments in the neighbourhood of the Virgin Islands were carried out by Villard, Stein, and Yeh (1957) employing fixed-frequency radar sounders located at St. Croix and by Dueno (1960) from Mayagiiez. Villard, Stein, and Yeh observed backscatter signals,. at frequencies up to 46� 2 Mc/s, corresponding to slant ranges up to 8000 km between 1500 and 2100 hr local time. These results were attributed to successive reflections from a tilted F layer without intermediate ground reflections (n F propagation). Dueno investigated the long-range trans-equatorial (LRTE) echoes at frequencies up to 49�68 Mc/s over a two-year period. He found a marked seasonal variation in the occurrence, the maxima occurring during the equinoctial periods. Low angle of arrival of the signals was deduced.
The Angular Distribution of 1·79 MeV Neutrons Scattered from Helium
Authors: Young PG , Ohlsen GG , Okhuysen PL
Published: May 2011

The angular distribution of 1�79 �O� 05 Me V neutrons scattered from 'He has been measured in an effort to settle" a discrepancy in the phase shifts. The laboratory angular range 25� to 135� was covered. The results are compared with differential cross sections computed from the phase shifts of Dodder and Gammel (1952) and Demanins et al. (1962), and the data are seen to agree best with the former.
Remarks on the Transport Properties of a Fully Ionized Gas with Application to a Radially Constricted Gas Discharge
Authors: Seymour PW
Published: May 2011

The correction of Vaughan-Williams and Haas to Marshall's l set of thermal conductivities for a fully ionized hydrogen isotope in the presence of a magnetic field is extended to thel?. and �q (or K) sets, and the high-field limits for the components perpendicular to the magnetic field are included.
The Silent and Hissing D.C. Electric Arc
Authors: Eather RH
Published: May 2011

The d.c. electric arcs between graphite, iron, and copper electrodes exhibit a sudden discontinuity in their volt� ampere curves. The acoustic noise emitted on the high current side of the discontinuity is much louder than on the low current side, and the two modes of arc operation are called the "silent" and "hissing" forms.
An Analytical Treatment of the Geometrical Properties of the Three-circle Goniometer
Authors: Sabine TM
Published: May 2011

The use of the three-circle goniometer for X-ray or neutron crystallography is described briefly. Equations are derived using vectorial methods for the computation of the angle settings of the instrument for three-dimensional data collection. These equations are derived for both procedures used in practice, namely, where the (h k 1) vector in reciprocal space is brought into coincidence with the scattering vector or when each zone a..-,;:is [u v w] is brought into coincidence with the axis of rotation of the diffractometer.
Moon Camera Values of ?T = ET? UT
Authors: Balfe JD
Published: May 2011

The ephemeris scale of time is based on the revolution of the Earth around the Sun. In 1956 the International Committee of Weights and Measures adopted a new definition of the second, the fundamental unit of time, in terms of ephemeris time. The second is the fraction 1/31556925� 9747 of the tropical year for 1900 January 0 at 12 hours, ephemeris time.
The Theory of Dispersal During Laminar Flow in Tubes. I.
Authors: Philip JR
Published: May 2011

This is the first of a series on dispersal under the combined influenoe of moleoular diffusion and convection in a fluid subject to steady Poiseuille flow in a straight oiroular tube.
The Theory of Dispersal During Laminar Flow in Tubes. II.
Authors: Philip JR
Published: May 2011

The solution of the problem introduced in Part I is found for the case of large diffusion P�clet number (Y). The work is carried out principally in the third approximation of the Galerkin method, and the results are presented in some detail.
A Theory Of Helium II
Authors: Macleod DB
Published: May 2011

In this paper, a new possible explanation of the properties of helium II is developed. The basis of the argument is that, due to the internal cohesion of a fluid, potential energy resides within the repulsive field of the atoms. This potential energy will tend to appear as kinetic energy if the fluid expands, but, under its own vapour pressure, the sum of the potential and kinetic energies will be a constant in the system and be intrinsic to it. Arguments based on this conception lead to an understanding of many of the peculiarities of helium II and also to a simple expression for the velocity of the "second sound wave".
Analysis of Overlapping Resonances in Proton?Carbon Scattering
Authors: Robson D , Toutenhoofd W
Published: May 2011

The R-matrix theory of nuclear reactions is discussed for the situation where distant levels must be included and is successfully applied to the elastic scattering of protons by l2C in the energy range ELAB = 10-11� 5 MeV, where the resonance levels are overlapping. Definite spin and parity assignments are made for three levels in this region by comparing the predicted excitation functions at several angles of scattering with experiment. Previously unexplained polarization data are explained by this analysis. The optical.model potential is found to be parity dependent for ELAB=8.5 MeV and yields a close fit to the available data at ELAB = 8�5 MeV.
The Decametric Radio Emissions of Jupiter
Authors: Ellis GRA , McCulloch PM
Published: May 2011

The cyclotron theory of the decametric radiations of Jupiter is examined in detail. Providing Jupiter is surrounded by an extensive ionized exosphere, it is shown that the theory accounts for the observed variation in the number of radiation bursts with planetary rotation, their polarization, and their spectra. It is found also that the average power of the bursts and their polarization are functions of the number of bursts.
The F2 Component of Cosmic Radio Noise Absorption
Authors: Ellis GRA
Published: May 2011

The attenuation of cosmic radio waves expected in the F region is calculated. It is shown that by using an F-region model obtained from electron backscatter measurements the attenuation obtained agrees well with observation. The amount of attenuation is generally less than 0�2 dB, providing the wave frequency is greater than twice f OF2 for wave frequencies less than 10 Mc/s.
Eccentric Dipole Coordinates
Authors: Cole KD
Published: May 2011

Recently, Bond and Jacka (1962) sought to order the average frequency of occurrence of visible auroras in eccentric dipole latitude. It is considered that eccentric dipole co-latitudes (q''), longitudes (f'), and times for places on the surface of the Earth (here assumed spherical) may be of interest to workers in various fields. Mapped grids of q'' and f' are reproduced here.
Microwave Interferometry for Plasma Studies
Authors: Robinson LC , Sharp LE
Published: May 2011

A beam of microwave radiation is a powerful and penetrating means of exploring the density and temperature of laboratory plasmas while causing minimal perturbation of the plasma. To a wave of frequency greater than the electron plasma frequency the plasma behaves like a dielectric, causing a change in the "optical" path which, when measured by interference techniques, yields the average electron density. The attenuation of the probing wave can give the collision frequency and hence the plasma temperature.
Wind-induced Stresses on Water Surfaces: A Wind-tunnel Study
Authors: Fitzgerald LM
Published: May 2011

A laboratory wind tunnel has been used to study the effect of wind on a water surface. The surface shearing stress 7'0 and the slope of the surface induced by wind have been measured. Values of the surface stress, in good agreement with each other, have been obtained from: (a) the velocity profile of the wind above the water surface, (b) the measured values of surface slope or set-up, and (c) the spreading characteristics of surface films. The drag coefficient, Cn = TO/ pu2n, was found to be constant for wind speeds up to about 412 cm/s and then to rise gradually for higher wind speeds.
The Type IV Solar Radio Burst at Metre Wavelengths
Authors: Weiss AA
Published: May 2011

Properties of 24 sources of type IV emission at metre wavelengths (including the long-lived continuum storms) have been observed by interferometry in the frequency range 40-70 Mc/s and by dynamic spectroscopy in the frequency range 15-210 Mc/s. The characteristics investigated are the positions, movements, and angular sizes of the sources, and the spectrum and polarization of the emission.
Observations of Galactic Radiation at 4·7 Mc/s
Authors: Ellis GRA , Green RJ , Hamilton PA
Published: May 2011

This paper describes observations of galactic radiation at 4� 7 Mcls using an antenna with a beam of 11 � by 3�. A range of declinations from -10� to -72� and of R.A. from 1200 h to 0500 h was surveyed. Brightness contours are given.
A Low Resolution Hydrogen-line Survey of the Magellanic System. II. Interpretation of Results
Authors: Hindman JV , Kerr FJ , McGee RX
Published: May 2011

A low resolution (202) survey of the neutral hydrogen in the Magellanic Clouds has produced two important additions to our knowledge of the system. (1) A bridge of gas between the Small and Large Cloud has been mapped. (2) The Small Cloud profiles show double peaks over a wide area, suggesting the possibility of two substantially separate masses of gas.
The Number of Independent Variables for an n-Particle Collision
Authors: Cunningham J
Published: May 2011

Suppose we have n vectors in a space of dimensionality v, n �v, and that we define scalar products 8ij between the vectors Pi as follows
Two-body Bound State and Scattering with Non-central Forces
Authors: Nicholson AF
Published: May 2011

A class of local potentials containing central, tensor, and L.S parts is con� sidered, for which the n-p coupled radial equations for the states of any J reduce to uncoupled equations over a region R of r. If R is finite all potentials may be of short range. The possibilities of describing the deuteron and n-p scattering by this model are considered. It is shown that the observed values of the high.-energy mixing parameters �4 may be fitted without solving the wave equations.
The Mechanical Impulse Method for Determining Dynamic Elastic Moduli and Internal Friction of Solids
Authors: Pollard HF
Published: May 2011

The theory governing the excitation of a linear mechanical system by delta function impulse is summarized. In the case of a finite elastic rod excited by an impulse, the Fourier transform of the output function enables the frequency spectrum of the rod to be obtained. A spectrometer for accomplishing this operation is described and a comparative study is made between the impulse and resonance responses of a cylindrical rod
Optimum Thermal Efficiency in Countercurrent Heat Exchangers
Authors: Bosworth RCL , Groden CM
Published: May 2011

When a heat exchanger operates on fixed hot and cold fluid streams and is.adjusted to give optimum efficiency, the measure of irreversibility produced by the.exchange process is a sum of two terms, one of which is proportional to the pivotal.temperature difference and the other to the terminal temperature difference.
Absolute Intensities of Characteristic Ka Radiation from an Inclined Copper Target
Authors: Metchnik V
Published: May 2011

Experimental results are given for the measurements of the absolute intensity of characteristic Ka radiation from a thick copper target when the normal to the target is inclined to the incident electron beam at an angle (I equal to 20�, 30�, 40�, and 50�. These measurements cover a range of electron energies between 20 and 50 kV, and take�off angles q, ranging from 1� to 50�. A comparison is made with the emission at normal incidence. The copper Ka radiation was isolated by means of balanced nickel and iron filters, and the intensity mllasurements were made with a scintillation counter with NaI(TI) crystal
A Sky Survey of Neutral Hydrogen at l 21 cm. III. Gas at Higher Radial Velocities
Authors: McGee RX , A Milton Janice
Published: May 2011

Information is presented concerning the distributions of the intensity and radial velocity of atomic hydrogen gas at radial velocities away from zero. The observations were made with an aerial beam of 2?2 between half-power points and a multichannel H-line receiver of channel spacing equivalent to 7 km/s and bandwidth 38 kc/s ( 8 km/s).
The Sextanid Meteor Stream
Authors: Nilsson CS
Published: May 2011

The Sextanid meteor shower was first reported by Weiss (1960), who matched theoretical envelopes to the echo range-time plot from a directive radar rate equipment to find the radiant = 155�8�, S = 0�1O�. The peak activity persisted from September 29 to October 3, but was noticeable only in 1957. No trace of activity due to this shower could be found in previous surveys.
Remarks on the Efficiencies of Geiger, Proportional, and Cintillation Counters with Application to the Absolute Intensity of Characteristic X-Radiation
Authors: Metchnik V
Published: May 2011

The measurements of the absolute intensities of Ou Ka radiation, isolated by means of balanced nickel and iron filters,. necessitated the determination of the quantum counting efficiency of three types of detectors: an end� window argon-filled Geiger counter, a two side-window, xenon-filled proportional counter, and a scintillation counter with NaITI crystal. It is shown that, provided the necessary corrections are made, results of absolute intensity measurements obtained with these three detectors show good agreement.
A Southern Hemisphere Radio Survey of Meteor Streams
Authors: Nilsson CS
Published: May 2011

A radio survey of the orbits of 2200 meteors of radio magnitude + 6 was made at delaide (latitude 35� S.) during 1961. The analysis of the data is fully discussed, together with the accuracy of the results. A method of defining and separating the shower meteors from the sporadic background is given. More than 60 separate radiants were delineated during 13 months of part-time recording. Olose attention has been paid to the statistical reality and distinctness of the minor radiants.
Sodium Layer Heights Over Antarctica
Authors: Cresswell GR
Published: May 2011

Measurements of the twilight sky luminosity variations in Na D at Saskatoon, Canada, were found by Hunten and Shepherd (1954) to be consistent with a distribution of sodium atoms centred at a height of 85 km with a scale height of 7�5 km above and below the peak, the luminosity being due to resonance scattering of sunlight. By fitting Hunten's (1954) luminosity curve to experimental data obtained in Australia and Antarctica, O'Brien (1960) found a sodium layer height of90�5 km
Statistical Mechanics of Almost One-dimensional Systems. II.
Authors: Barker JA
Published: May 2011

Previous results on the statistical mechanics of almost one-dimensional systems of molecules or atoms are generalized to allow for the presence of a longitudinally varying external potential energy field. Methods for calculating the local density and higher order distribution functions are described. Equations valid for mixtures of molecules of different kinds are derived. Possible applications of the theor{jtical results are indicated and a detailed application to the twodimensional hard disk system is described.
The Motion of Charged Particles in the Vicinity of Magnetic Neutral Planes with Applications to Type III Solar Radio Bursts
Authors: Weiss AA , Wild JP
Published: May 2011

The equations of motion for a charged particle of constant energy injected into or near a neutral plane separating two opposing magnetic fields are integrated by approximate analytical methods. The simplest relevant field configuration, with an arbitrary intensity gradient in one direction, is chosen. The trajectories of particles injected at arbitrary angles and at points in or near to the neutral plane are discussed in detail.
Diffusion of Meteor Trails in the Earth's Magnetic Field
Authors: Francey JLA
Published: May 2011

The. diffusion equation is solved for isotropic diffusion in the absence of external forces. The asymmetry due to an external magnetic field is introduced and solutions of the diffusion equation are given for the two cases of magnetic field parallel and erpendicular to the diffusing coluIIlI!-'
Diurnal Variations in the Power Spectrum and Polarization of Telluric Currents at Conjugate Points, L = 2·6
Authors: Mather KB , Gauss EJ , Cresswell GR
Published: May 2011

The power spectrum of telluric currents, at the sub-auroral latitude where L = 2�6, shows a pronounced diurnal variation. The variation is contributed mainly by a strong peak at about 40 s, which shows a large cyclic fluctuation in amplitude and also a tendency to shift in frequency. The amplitude is larger and the period somewhat shorter during the day-time. The 40-s peak is also subject to appreciable random fluctuation in period. The spectrum shows shorter periods (7-14 s), and longer periods (several hundred seconds) in addition to the 40-s peak. There is a general shift to slightly longer periods at the time of auroral onset. The spectra are compared with those obtained at other latitudes. A period of about 40 s appears to have a wide distribution in latitude. It can be followed from mid latitudes to latitudes in the auroral zone and polewards of the auroral zone. The ignificant variation with geomagnetic latitude seems to be the relative amount of power associated ith anyone period rather than in the period itself. The observations are not readily econciled with theoretical estimates of magnetospheric oscillation in the transverse and compressional modes.
Average Radiation-pressure Forces Produced by Sound Fields
Authors: Smith WE
Published: May 2011

Radiation-pressure forces developed within an acoustic system may be calculated from a detailed knowledge of the fields. It is shown that the time average of a generalized radiation-pressure force may be expressed in terms of quantities on an arbitrary mathematical surface enclosing the system.
Radial Velocities Associated with Selected Emission Nebulae in the Small Magellanic Cloud
Authors: Bok BJ , Gollnow H , Hindman JV , Mowat M
Published: May 2011

Radial velocities for nine bright emission nebulae in the bar of the Small Cloud of Magellan are presented together with the corresponding profiles of 2l-cm line emission from neutral hydrogen.
Geomagnetic and Ionospheric Effects at Brisbane Following the Nuclear Explosion on July 9, 1962
Authors: Bowman GG , Mainstone JS
Published: May 2011

Ionospheric data and geomagnetic micropulsation records from Brisbane have revealed both short� term and delayed effects associated with the U.S. nuclear explosion on July 9, 1962 above Johnston I. The initial ionospheric effects, lasting about 30 s, appeared to be due to severe low�level (D-region) blanketing, probably arising from the dumping of neutron decay products. The micropulsations initiated by the explosion were detected for about 5 min; after an initial transient, they became suppressed during the time when the low-level blanketing ionization was present.
Dislocation Substructures in Deformed and Recovered Chromium
Authors: McLaren AC
Published: May 2011

In an attempt to correlate the degree of plastic deformation of chromium with the physical properties associated with its antiferromagnetism, a study has been made by thin-foil electron microscopy of the dislocation substructures in polycrystalline chromium sheet after deformation by rolling and subsequent annealing. The original hot-rolled sheet exhibited a typical cell structure.
Calculations of Intensities of Emission of Characteristic X-Radiation
Authors: Tomlin SG
Published: May 2011

Intensities of emission of characteristic X-radiation from thick targets of silver, copper, chromium, aluminium, carbon, boron, and beryllium have been calculate using the theory of Metchnik and Tomlin (1963) and the results have been compared with experimental data. The effect of the backscattering of electrons from the target has been examined in detail, and the correcting factor k, which allows for this and for the effects of luorescence yield and indirect excitation by the white radiation, has been tabulated.
Ionospheric Irregularities and High-multiple Reflections
Authors: Bowman GG
Published: May 2011

The occurrence of high� multiple reflections (10 hops and more) from the F. layer of the ionosphere at night is considered. Sunspot-cycle, annual, and diurnal variations are presented. The sunspot. cycle and annual variations are similar to those for the upper-atmosphere neutral particle density. Periodicities in occurrence of around 60 min are found. Associations are found between high-multiple trace occurrence and sunset and sunrise times at the 90 km level. Ionospheric irregularities which are present at the time of high.multiple reflections indicate that these reflec� tions are probably not due to focusing effects. Evidence is presented to support a mechanism involving the reduction of non�deviative absorption to explain these reflections. This reduction may be caused by acoustic waves propagating in the high atmosphere.
Vela?Puppis Meteor Shower Activity
Authors: Ellyett CD , Roth KW
Published: May 2011

It has become established from radar surveys at Christchurch, New Zealand, in 1953, 1956, and 1960 that very strong meteor shower activity occurs annually in December, with radiants in both the Vela and the Puppis constellations. The Velid group has a mean right ascension of about 134�, and the Puppid group is rather widely spread around llO�. The declination of both showers is about _45�.
The Allowed and Forbidden Transitions in the Paramagnetic Resonance of the Manganese Ion in Trigonal Sites in Apatite and Smithsonite
Authors: Burley SP
Published: May 2011

The allowed and forbidden paramagnetic resonance transitions of MnH ions in single crystals of apatite [CalO(PO.). (F, CI)] and smithsonite [ZnCO.] have been investigated. The spin Hamiltonian parameters, describing the spectra observedat 300oK, were found from a third-order perturbation-theory estimate of the eigenvalues, calculated for the cases in which the magnetic field was parallel and perpendicular to the trigonal axis. Since in the case of apatite the D term was not very small compared with the Zeeman term, it had to be included also in the zeroth-order Hamiltonian.
Paramagnetic Resonance of Cu2+ and Ti3+ Ions in Borax Beads
Authors: Burley SP
Published: May 2011

Paramagnetic resonance absorption has been observed in borax beads containing CuH and Ti3+ ions. In these cases broad lines were observed near g = 2, but hyperfine structure was also apparent in the case of the CuH ions, making it possible to estimate average values of the spin Hamiltonian parameters. Analysis of the results indicated that the CuH and Ti3+ ions occurred in octahedral complexes with very strong axial deformations.
Axial Ratio of the Projected Polarization Ellipse
Authors: Late S Ramu The
Published: May 2011

The axial ratio of the polarization ellipse of a radio wave is often evalp,ated using a crossed-dipole antenna system placed in a horizontal plane. The axial ratio of the ellipse as deduced from the responses of the two antennas should correspond to the axial ratio of the ellipse in the wave-front as projected onto the horizontal plane. When one of the two dipoles is situated in the plane of incidence of the radio wave, the axial ratio of the projected polarization ellipse is a function of the angle of incidence and the orientation of the polarization ellipse in the wave-front. A convenient parameter with which to relate axial ratio and orientation is the angle made by the major axis with the line of intersection of the wave-front with the horizontal plane. This line would actually correspond to the direction of one of the dipoles when the other is situated in the incident plane.
Variation of Proton Flux with Atmospheric Depth Between 10 and 50 g/cm2 at l = 47° S. Geomagnetic
Authors: Wu KKM , Chow BSK
Published: May 2011

Proton fluxes at atmospheric depths between 10 and 50 g/cm2 have been measured using nuclear emulsions during a series of balloon flights over Melbourne (A = 47� S. geomagnetic) in the period November 1961-April 1962. The proton flux J(x) decreases with increasing depth within this region. It can be represented by the relation log J(x) = (3�05�0�02)-(2�36�0�66)xlO-3x and, when extrapolated, gives the flux at the top of the atmosphere to be 1120�50 protons m-2 steradian-1 S-l.
The Speed and Acceleration of the Sources of Type III And Type V Solar Radio Bursts Over Large Distances in the Corona
Authors: Stewart RT
Published: May 2011

The outward velocity and acceleration through the solar corona of the disturbances responsible for the emission of 50 type III bursts recorded on the Dapto radio spectrograph are investigated by applying standard electron density models for the corona to the frequency drift of each burst. If current models for an active region are assumed, the velocities often remain unchanged from the lower corona out to heights of at least two solar radii above the photosphere. The mean velocity is about ie. Speeds of sources of type III bursts followed by type V continuum are similar to those for isolated type III bursts.