Astrophysics and Astronomy Commons^™

Neutron And Proton Measurements Of Oso-6 Near The South Atlantic Radiation Anomaly., Philip Jay Cooper

Physics & Astronomy ETDs

The University of New Mexico High-Energy Neutron Experiment flown aboard NASA Satellite OS0-6 in 1969 was designed and built to study neutrons at an altitude of 􀀄500 km, above the earth's dense atmosphere. The detector was a proton recoil telescope with directional discrimination and was sensitive to protons as well as neutrons. Neutron data from August, 1969 to January, 1971 was analyzed in the energy range 40-120 Mev. Proton data in the energy range 60-170 Mev obtained during October and November of 1969 was also analyzed. Analysis was limited to the region of space known as the South Atlantic Radiation …

Calculation Of Potential Functions For Pseudorotation In Five Membered Rings Using Energy Gradients In Extended HüCkel Theory, Thomas Robert Ferguson

Physics & Astronomy ETDs

The gradient of the energy in extended Hückel theory (EHT) was used in a variable metric algorithm to predict the energy along the pseudorotational path for several five membered ring molecules. The molecules studied were cyclopentane, tetrahydrofuran (THF), cyclopentanol, 4-tetrahydrofuranol, and cis- and trans-3,4-tetrahydrofurandiols. Comparisons of predictions for these molecules to experimental results were made to determine the capabilities of EHT prior to an intended study of sugar rings. A background chapter discusses the recent literature on nucleic acid constituents with emphasis on the geometries of five membered sugar rings. In crystals, these geometries are found to lie mostly in …

A Method For Measuring The Electrical Conductivity Of A Shocked Liquid, Richard James Hassman

Physics & Astronomy ETDs

Development of a simple technique for the measurement of the gross electrical conductivity of a shock compressed liquid is attempted. A cell containing the sample is constructed from glass cylinders and aluminum foil. The foil is sandwiched between two cylinders of the same diameter to form a two compartment cylinder. The cylinder is mounted on a metal target plate. With both chambers of the system full of liquid, only insignificant reflections can arise from the sample-foil interface. A voltage is placed across the cell between the foil and the target plate, and the change in voltage as the shock front …

A Photographic Study Of The Infrared Oh Airglow, G. C. Loos

Physics & Astronomy ETDs

OH airglow is due to the rotational-vibrational transitions of the hydroxyl radical. Previous efforts to find the airglow's emission height in the atmosphere are discussed. Photography of the infrared airglow with a fast 35mm camera and Eastman Kodak high speed infrared film is described and a method for triangulating emission heights by two station photography is explained. The techniques for reduction of film data to height measurements and velocity measurements are presented. Observations are reported concerning the frequency of occurrence of bright spots and other features on the OH background and the intensity of the airglow as a function of …

Intensity Correlation Spectroscopy Of Heme Proteins And Motile Microorganisms, Gordon E. Banks

Physics & Astronomy ETDs

The recently developed technique of autocorrelation of intensity fluctuations of Rayleigh (quasi-elastically) scattered light allows measurement of some dynamic properties of particles in solution. The origin of the intensity fluctuations and the form of the correlation spectra for various situations are discussed. The apparatus and methods are described along with methods of data reduction and sources of error. Measurements were made using a Spectra-Physics Model 125 (50mW) He-Ne laser (6328Å) in conjunction with a Saicor 43A 400 channel correlation and probability analyzer. The diffusion coefficient of cyanometmyoglobin was found to be D_{20, w} = (9.47 ± 0.28) x 10 …

Dynamic Impulse Calibration Of Sheet Loaded Explosive, William James Johnson

Physics & Astronomy ETDs

In the past, experimenters have used Sheet Loaded Explosive (SLE) to simulate the damage caused by x-rays to an ICBM as the result of a nuclear burst from an ABM. One of the attractive features of SLE is that it can also provide high impul3e levels for structural damage studies. Previous measurements of the usual shock parameters such as peak overpressure, ietonation velocity, and shock front definition with short time interval pressure transducers were not suitable for total impulse measurements. The High Explosive Impulse Responder (HEIR) was developed to fill the need for a simple, reliable and economical total impulse …

Effects Of Pressure On The Rotational Phase Transitions And Dielectric Properties Of Solid Cyclopentanol, David Nason Glidden

Physics & Astronomy ETDs

The dielectric constant and loss for solid cyclopentanol have been measured at hydrostatic pressures up to 2.5 Kbar for frequencies of 1 KHz to 5 MHz from 258 °K to 200 °K. Activation parameters have been calculated from the experimental data. In addition, activation parameters have also been calcuated from a fluctuation-barrier model for dipole reorientation and compare favorably with the experimental quantities. The dielectric constant shows that the phase transition from form I, with sperically symetric orientational freedom, to form II, with restricted orientational freedom, is readily brought about at these pressures. This phase transition was elucidated by an …

First Measurements Of Earth Albedo Neutrons In Space, James R. Place

Physics & Astronomy ETDs

NASA satellite OSO-6 carried as part of its payload a proton recoil telescope capable of detecting neutrons between 40 and 200 MeV with directional discrimination. Sixteen months of data from this instrument were analyzed with a view to determining properties of the earth albedo neutron flux above the atmosphere.

The variation of albedo neutron flux with geomagnetic latitude was found to be 1:4 between 0° and 40°. The angular distribution shows that about 40% fewer neutrons come upward from directly beneath the satellite compared to the number coming from a direction tangential to the top of the atmosphere. These results …

Light Scattering From Mammalian Cells., Albert Brunsting

Physics & Astronomy ETDs

Light scattering intensity functions for concentrically coated spheres (core diameter 7 mu and total sphere diameter 10 mu, approximately) have been computed. The coated spheres model many types of nearly spherical mammalian cells whose nuclei have a low relative refractive index (~1.05) and cytoplasm with a slightly lower relative refractive index (~1.03). Studies are made on the relationships between the scattering coefficients for nonadsorbing, spherically symmetric scatterers. The physical origin of these coefficients is examined for absorbing scatterers. Diffraction accounts for most of the light scattered in the forwards lobe, whereas at larger angles the coated sphere scattering patterns are …

Development Of The Oso-6 High-Energy Neutron Detector And Correlation Of Measured Solar Neutron Fluxes To Solar Flares, Frederick Young

Physics & Astronomy ETDs

In an attempt to understand certain of the high energy processes that occur in the solar and terrestrial atmospheres and the interplanetary medium a detector of 20 to 160 MeV neutrons had been designed and constructed for inclusion in the NASA Orbiting Solar Observatory, Satellite OSO-G, which was launched into a near circular orbit at approximately 500 km altitude in August 1969. Both the angle of incidence and the energy of the neutron are determined by a telescopic arrangement of four scintillation plastic counters (Pilot B; hydrogen to carbon ratio 1:1) which generates proton recoils and provides pulse heights for …

Cellular Absorbed Dose Spectrometer (Cads) Data Reduction And Analysis., John T. Cervini

Physics & Astronomy ETDs

A detailed description of a space qualified linear energy transfer (LET) spectrometer is presented. The Cellular Absorbed Dose Spectrometer (CADS) is a prototype instrument which was launched on March 17, 1969 into an elliptical orbit. Its purpose was to obtain the first successful LET measurements in space; and, thereby provide additional data to assess the biological hazards of the near earth space environment, especially during periods of in­creased solar activity.

The physical processes that take place in the CADS in­strument are discussed, and a definition of linear energy transfer is given, as well as its relation to dE/dx. The performance …

Measurement Of The Average Solar Neutron Flux And Its Correlation With Solar Activity, Pyung Syk Ro

Physics & Astronomy ETDs

Data from the University of New Mexico High Energy Neutron Detector flown on NASA satellite OSO-VI arc analyzed with the aim of detecting neutrons from the sun. The detector is a proton recoil telescope capable of directional discrimination and responsive to neutrons of energies between 20 and 200 MeV with an effective average efficiency for this analysis of 10^-4 and an effective area of 80cm². The detector was located in a wheel compartment of OSO-VI and scanned the sun once per revolution of the wheel at a rate of 30 rpm. The satellite was launched on August …

Increasing The Efficiency Of A Surface Ionization Mass Spectrometer, Thomas Curtis Adams

Physics & Astronomy ETDs

An Avco surface ionization mass spectrometer (model 90,000) was installed at the Los Alamos Scientific Laboratory in February, 1968. Since that date this machine has been used as a production instrument for the isotopic analysis of uranium and plutonium samples. During 1969, it was realized that a problem inherent in the ionization mechanism of the instrument was degrading the accuracy of results, and that the number of man-hours expended in reducing data had become excessive. As soon as this situation became apparent, corrective action was initiated to reduce the effect of the ionization problem and to decrease the amount of …

Intensity Ratios For Polarized Refracted Light Near The Critical Angle., Stephanie Layne Moore

Physics & Astronomy ETDs

It was undertaken to investigate the intensity ratio of refracted light polarized parallel and perpendicular to the plane of incidence. The primary object of the experiment was to obtain this ratio for light incident at very nearly the critical angle on a water-air interface, the light having first passed through the water. A laser was used to produce the light beam and the experimental results were compared with the theory propounded by Fresnel for infinite plane waves and elsewhere asserted to hold for bound plane waves. As this theory predicted a ratio of the square of the refractive index (n) …

Dielectric And Phase Behavior In Solid Cyclopentanol., Stephen John Dalich

Physics & Astronomy ETDs

The dielectric and phase properties of cyclopenthanol have been investigated using dielectric constant measurements and visual observations. As a result of these studies a model has been constructed which accounts for the observed dielectric and phase behavior in solid cyclopentanol.

From the dielectric studies three distinct solid forms have been identified in a region from the melting point at -17.5 C to -80 C. Two of these, forms I and II, are rotational phases, the third is nonrotational. The studies have concentrated on the two rotational forms and the transition between them.

The previously reported dielectric anomalies have been investigated …

Linear Pulsation Analysis Of Cluster Cepheid Variables, Charles E. Needham

Physics & Astronomy ETDs

Models for thirteen classical Cepheids found in galactic clusters or associations are analyzed. The models are calculated using the most recently published photometric data and theoretical evolutionary tracks. The linearized equations of mass, momentum and energy conservation are solved subject to an infinitesimal radial perturbation of each equilibrium model. The equations are first solved in the adiabatic approximation. This solution is then used as the initial value for the iterative solution of the non-adiabatic equations. The linearized analysis provides information on pulsation periods of fundamental and harmonic modes, stability against pulsations and phase differences between various physical parameters, such as …

A Vibrational And Rotational Analysis Of Eight Simple Models Of The Hydrogen Molecule In The Ground State., Stuart Fleming Hayes

Physics & Astronomy ETDs

The object of this dissertation was the investigation of the influence on the delta G curve for H2 of polarization, enhancement of charge between the nuclei, and variation of the screening parameter. A better understanding of the influence of these factors could lead to progress in estimating more accurately the dissociation energies of diatomic molecules. Also to be investigated was the correlation between these factors and the vibrational and rotational spectroscopic constants, particularly Bv.

The Heitler-London combination of atomic orbitals (referred to as phi 1) was used in every wave function The atomic orbital 2pz was used in phi 2 …

A New Method In The Wkb Approximation, Raymond Pierce Engelke

Physics & Astronomy ETDs

A new WKB-like quantization rule is developed by means of a transformation method. This method makes use of a combination of a Liouville-like substitution and the Prüfer transformation. The only quality required of the potential is that it be twice differentiable on the real axis. The new quantization rule is an exact rule. However, some terms in the rule must be approximated before it can be evaluated for any particular potential function. An interesting feature of the derivation is that no asymptotic expansions are used -- unlike the usual development of the 1st order WKB quantization rule (FWKBQR). The terms …

Molecular Orbital Calculations To Determine Stable Conformations Of The Nucleotide Deoxycytidine-3'-Monophosphate., Marvin Lawrence Chatkoff

Physics & Astronomy ETDs

Extended Huckel, semi-empirical, molecular orbital analyses were performed for deoxycytidine-31 -monophosphate and cytidine-3'-monoohosphate corresponding to single nucleotides of double helical DNA and RNA to determine whether the experimentally derived models correspond to theoretically stable configurations. The A, B, and C models of DNA, and linearly interpolated intermediate con­figurations were investigated. For RNA, the experimental A configuration, a pseudo RNA nucleotide formed from the B configuration of DNA, and intermediate conformations were used.

From the B model of DNA the base was displaced and angles adjusted until close coordinate fits were obtained at the A and C configurations. Intermediate points were …

Propagation Of Ultrasound In Plastic Crystals, Carl E. Scheie

Physics & Astronomy ETDs

The study of the organic solid state, and in particular of plastic crystals, is a relatively new branch of physics (1,2). Timmermans first surmised the existence of these solids from the anomalous values of the entropies of fusion. The solids possess many of the characteristics of liquids. They are easily deformed by pressure and they show dielectric properties that can be described on the basis of rotation of the molecules in their lattice positions. Still they have a definite crystal structure. Thus, even though the molecules are not symmetric, they appear to be to some degree because of the rotation. …

Measurement Of Cyclohexane Ultrasonic Velocity Using Photon-Phonon Scattering Interactions, Edward W. Taylor Jr.

Physics & Astronomy ETDs

The construction of a frequency modulated optic cell and its operation for studying the ultrasonic velocities of cyclohexane, acetone and ethyl alcohol as a function of temperature is described. A description of photon-phonon scattering interactions is presented. The appearance of the intensity distribution of the scattered light is treated, and an analysis of the experimental results is included. The special scattering case of Bragg diffraction of coherent light was used for determining the ultrasonic velocities of cyclohexane as a function of temperature. Ramifications of the Raman-Nath and Bragg diffraction effects are discussed. The relationship v_T = 1376.78 - 5.25 …

Fission Barriers And Transition-State Spectra For 232th, 234th, 238u, 240u, 242pu, And 244pu From 9t, Pf0 Reactions., James D. Cramer

Physics & Astronomy ETDs

Joliot and Curie’s discovery of artificially induced radio-activity in several nuclei by a-particle bombardment encouraged Fermi and his collaborators in 1934 to attempt similar experiments using neutron bombardment of various target elements/ Using natural uranium as a target material they discovered at least four radioactive products, assumed to be elements in the transuranium region. These experiments were repeated in 1937 by Meitner, Hahn and Strassman in Germany where they found that some of these radioactive elements produced by neutron bombardment of uranium had barium-like chemistry, and were assumed to be isotopes of radium. Further investigation proved that these products could …

The Monte Carlo Method Applied To An Estimation Of Delayed Neutron Response, Garland David Turner

Physics & Astronomy ETDs

An experimental program has been undertaken at Los Alamos Scientific Laboratory to study delayed neutron effects. As a part of this program, experiments were conducted with thin disks of various fissionable materials to measure the delayed neutron response to a pulse of high-energy neutrons. In support of the experiments, calculations were made with a computer program which solves the Boltzmann transport equation by finite difference methods. Difficulties with the calculations led to an analysis showing that correct treatment of neutrons moving parallel to the faces of the disk was vital to the success of the calculation. As an extension of …

Cosmic Ray Anisotropy In Interplanetary Space, Jacqueline Hope Ericksen

Physics & Astronomy ETDs

The solar diurnal variation of cosmic ray intensity results from an interaction of cosmic rays with the co-rotating spiral interplanetary magnetic field. Changing interplanetary conditions might therefore be reflected in the diurnal variation. In this dissertation, the dependences of the quiet-day solar diurnal variation on the general level of solar activity and on the interplanetary sector structure are investigated. It is found that the amplitude of the solar diurnal variation as recorded by the Embudo and Bolivia multidirectional underground muon telescopes is significantly smaller near solar minimum (1965) as compared to solar maximum (1968). This amplitude dependence is associated with …

Theoretical Determination Of The Spectroscopic Constants Of The H₂ Ground State, Fun-Min Wu

Physics & Astronomy ETDs

Recently the h2 ground state potential E was calculated in double precision by Kolos and Wolniewicz using a 1oo-term wave function. For this kw potential the coefficients in a power series expansion about the potential minimum re are here determined by using the pure electronic potential and central differences. Resulting Dunham potential coefficients Ao, A1, A2, A3, A4, A5, and A6 are 79703 cm-1, -1.6031, 1.865, -1.999, 2.048, -2.02 and 2.0, respectively. From these coefficients the spectroscopic constants are found to be yoo = 8.36, y10 = 4406.6, y20 = -122.6, y3o = 1.2, y40 = -0.04, yo1, = 60.838, …

A Study Of The Sidereal Diurnal Variations Of Cosmic Rays Underground., Albert Brunsting

Physics & Astronomy ETDs

The sidereal diurnal variation of cosmic rays has been measured using underground (40 m.w.e.) meson telescopes located near Albuquerque, New Mexico (35.20°N, 106.41°w) and at Chacaltaya, Bolivia (16.31°s, 68.15°w). Each ofthe two locations has telescopes which scan the vertical and four inclined directions.

Two and three complete years were used for the tele­scopes at the Bolivia and New Mexico locations respectively. The average solar diurnal variations were calculated for each telescope for each month. Based on these monthly averages, the sidereal diurnal variations were computed. A correction was made in the analysis for any yearly modulation of the solar diunal …

A Shock Tube Study Of Recombination In The Lean Hydrogen-Oxygen Reaction Based On The Infrared Emission From Water Vapor, Larry S. Blair

Physics & Astronomy ETDs

ABSTRACT

Recombination in the hydrogen-oxygen reaction has been studied by monitoring the growth of infrared emission at 2.7 microns from water vapor as it is formed behind incident shock waves. Experiments were carried out in gas mixtures with hydrogen-to-oxygen ratios between 1.0 and 0.33 and temperatures between 1435° and 1868°K. Reactants were diluted with 92-98% argon. The validity of the transparent gas approxi­mation (emission intensity proportional to (H20]) and the relationship between emission intensity and temperature were established by cali­bration experiments in which mixtures of water vapor and argon were shock-heated to temperatures between 1328° and 1982°K. Analysis of H20-emission …

Meteorological Effects On Cosmic Rays At Albuquerque, New Mexico., David Nason Glidden

Physics & Astronomy ETDs

Ground-based observations of cosmic-ray intensity have the disadvantage of being more sensitive to variations of atmospheric temperature and pressure than to the more interesting variations in the primary cosmic radiation. It is, therefore, imperative to correct the recorded cosmic-ray intensity for variations of atmospheric origin before studies can be made of the smaller variations of the primary cosmic ray intensity.

In this thesis an attempt has been made to remove the variations of atmospheric origin from the cosmic-ray intensity recorded simultaneously by a neutron monitor and a meson telescope located at Albuquerque, New Mexico. It was found that the neutron …

Theoretical Analysis Of The Vibrations And Rotations Of The B¹[Sigma][Mu] State Of The Hydrogen Molecule, Sandra Zink Moody

Physics & Astronomy ETDs

Theoretical calculations of the rotational-vibrational constants of the B¹Σ⁺_u state of H₂ were made using the Dunham analysis and by fitting equations to energy eigenvalues. The potential energy function for the nuclei used in the calculations was computed by W. Kolos and L. Wolniewicz using the variational technique. The power series used in the Dunham analysis made use of Stirling's central difference interpolation polynomial. The equilibrium separation R_e found from the Born-Oppenheimer potential is 2. 42916₅ atomic units, differing from the Kolos-Wolniewicz value of 2.4288. Adiabatic corrections were taken into account through a …

Response Prediction For The Oso-G Satellite Solar Neutron Instrument By Matrix Methods., John Coalmer Conklin

Physics & Astronomy ETDs

Properties of the University of New Mexico’s solar neutron instrument for use on the NASA 0S0-C satellite were investigated. A sensor model was developed by use of two computer codes. First, the total efficiency of the converters was calculated by a simulation code with a resulting total efficiency at 100 Mev of approximately two per cent of which four-fifths was carbon recoil contribution.

Second, geometry properties of the instrument were provided by a Monte Carlo program, with maximum geometry efficiency equaling about fourteen per cent. These were combined to give a total response profile for the instrument which was expressed …