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Articles 6811 - 6840 of 8870

Full-Text Articles in Astrophysics and Astronomy

Mosaicking With Cosmic Microwave Background Interferometers, Emory F. Bunn, Martin White Jan 2007

Mosaicking With Cosmic Microwave Background Interferometers, Emory F. Bunn, Martin White

Physics Faculty Publications

Measurements of cosmic microwave background (CMB) anisotropies by interferometers offer several advantages over single-dish observations. The formalism for analyzing interferometer CMB data is well developed in the flat-sky approximation, which is valid for small fields of view. As the area of sky is increased to obtain finer spectral resolution, this approximation needs to be relaxed. We extend the formalism for CMB interferometry, including both temperature and polarization, to mosaics of observations covering arbitrarily large areas of the sky, with each individual pointing lying within the flat-sky approximation. We present a method for computing the correlation between visibilities with arbitrary pointing …

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A Dyad Theory Of Hydrodynamics And Electrodynamics, Preston Jones Jan 2007

A Dyad Theory Of Hydrodynamics And Electrodynamics, Preston Jones

Publications

The dyadic calculus is developed in a form suitable for the description of physical relations in curved space. The 4-space equations of hydrodynamics and electrodynamics are constructed using this dyadic calculus. As a demonstration of the relationship between gravity and electrodynamics a time varying metric is shown to generate electromagnetic radiation.

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Virgo’S Intracluster Globular Clusters As Seen By The Advanced Camera For Surveys, Benjamin F. Williams, Robin Ciardullo, Ted Von Hippel, Et Al. Jan 2007

Virgo’S Intracluster Globular Clusters As Seen By The Advanced Camera For Surveys, Benjamin F. Williams, Robin Ciardullo, Ted Von Hippel, Et Al.

Publications

We report the discovery of four candidate intracluster globular clusters (IGCs) in a single deepHST ACS field of the Virgo Cluster. We show that each cluster is roughly spherical, has a magnitude near the peak of the Virgo globular cluster luminosity function, has a radial profile that is best fitted by a King model, and is surrounded by an excess of point sources that have the colors and magnitudes of cluster red giant stars. Despite the fact that two of our IGC candidates have integrated colors redder than the mean of the M87 globular cluster system, we propose that …

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Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty Jan 2007

Strain-Based Electrical Properties Of Systems Of Carbon Nanotubes Embedded In Parylene, David D. Allred, Jon Brame, Johnathan Goodsell, Stephanie Getty

Faculty Publications

We have fabricated flexible electronic devices to test the strain-based change in resistance of a network of single-walled carbon nanotubes (SWCNTs) for use in microscale, high resolution magnetometry. To do this, we first develop a simple, reliable method to obtain catalyst nanoparticles for carbon nanotube growth through indirect, thin-film evaporation. Next we fabricate a two-terminal SWCNT device on a rigid substrate. We then transfer the device, intact, to a flexible substrate for strain testing. Herein, we report progress in growth and measurement techniques.

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Purification By Fire : 2 Peter 3 And The Stoic Cosmos, Peter G. Speiser Jan 2007

Purification By Fire : 2 Peter 3 And The Stoic Cosmos, Peter G. Speiser

Master of Arts Theses

No abstract provided.

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Reissner–Nordstrom¨ Expansion, Emil Prodanov, Rossen Ivanov, V.G. Gueorguiev Jan 2007

Reissner–Nordstrom¨ Expansion, Emil Prodanov, Rossen Ivanov, V.G. Gueorguiev

Conference papers

We propose a classical mechanism for the cosmic expansion during the radiation-dominated era, assuming the Universe as a two-component gas. The first component is the ultra-relativistic “standard” fraction described by an equation of state of an ideal quantum gas of massless particles. The second component consist of superheavy charged particles and their interaction with the “standard” fraction drives the expansion. This interaction is described by the Reissner–Nordstr¨om metric purely geometrically — the superheavy charged particles are modeled as zero-dimensional naked singularities which exhibit gravitational repulsion. The radius of a repulsive sphere, surrounding a naked singularity of charge Q, is inversely …

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Algorithm Refinement For Fluctuating Hydrodynamics, Alejandro Garcia, S. Williams, J. B. Bell Jan 2007

Algorithm Refinement For Fluctuating Hydrodynamics, Alejandro Garcia, S. Williams, J. B. Bell

Faculty Publications

This paper introduces an adaptive mesh and algorithm refinement method for fluctuating hydrodynamics. This particle-continuum hybrid simulates the dynamics of a compressible fluid with thermal fluctuations. The particle algorithm is direct simulation Monte Carlo (DSMC), a molecular-level scheme based on the Boltzmann equation. The continuum algorithm is based on the Landau–Lifshitz Navier–Stokes (LLNS) equations, which incorporate thermal fluctuations into macroscopic hydrodynamics by using stochastic fluxes. It uses a recently developed solver for the LLNS equations based on third-order Runge–Kutta. We present numerical tests of systems in and out of equilibrium, including time-dependent systems, and demonstrate dynamic adaptive refinement by the …

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Infrared Spectroscopy Of Symbiotic Stars. V. First Orbits For Three S-Type Systems: Henize 2-173, Cl Scorpii, And As 270, Francis C. Fekel, Kenneth H. Hinkle, Richard R. Joyce, Peter R. Wood, Thomas Lebzelter Jan 2007

Infrared Spectroscopy Of Symbiotic Stars. V. First Orbits For Three S-Type Systems: Henize 2-173, Cl Scorpii, And As 270, Francis C. Fekel, Kenneth H. Hinkle, Richard R. Joyce, Peter R. Wood, Thomas Lebzelter

Information Systems and Engineering Management Research Publications

Infrared radial velocities have been used to compute first orbits of the M giants in three southern S-type symbiotic systems. Of the three, Hen 2-173 has the longest orbital period, 911 days, and also has a noncircular orbit with an eccentricity of 0.21. The large value of its mass function suggests that Hen 2-173 may be an eclipsing system. For CL Sco our spectroscopic orbital period of 626 days is essentially identical to the previously determined light variability period of 625 days, and we have adopted the latter. AS 270 has an orbital period of similar length, 671 days, and …

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The Record-Breaking Rotational Braking Of The He Strong Cp Star Hd 37776, Zdeněk Mikulášek, Jiří Krtička, Juraj Zverko, Gregory W. Henry, Jan Janik, Iosif I. Romanyuk, Jozef Ziznovsky, Hrvoje Božić, Miloslav Zejda, Thomas Graf, Martin Netolický Jan 2007

The Record-Breaking Rotational Braking Of The He Strong Cp Star Hd 37776, Zdeněk Mikulášek, Jiří Krtička, Juraj Zverko, Gregory W. Henry, Jan Janik, Iosif I. Romanyuk, Jozef Ziznovsky, Hrvoje Božić, Miloslav Zejda, Thomas Graf, Martin Netolický

Information Systems and Engineering Management Research Publications

We study the long-term light and spectral variations in the He-strong magnetic chemically peculiar star HD 37776 (V901 Ori) to search for changes of its 1.5387 d period in 1976-2007. We analyze all published photometric observations and spectrophotometry in the HeI 4026 A line. The data were supplmented with 506 new (U)VB observations obtained during the last 2 observing seasons, 66 estimates of HeI equivalent widths on 23 CFHT spectrograms and 35 of the 6-m Zeeman spectrograms. All the 1895 particular observations heve been processed simultaneously. We confirm the previously suspected increase of the period in HD 37776 which is …

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Maya Eclipses: Modern Data, The Triple Tritos And The Double Tzolkin, William Earl Beck Jan 2007

Maya Eclipses: Modern Data, The Triple Tritos And The Double Tzolkin, William Earl Beck

Electronic Theses and Dissertations

The Eclipse Table, on pages 51-58, of the Dresden Codex has long fascinated Maya scholars. Researchers use the mean-value method of 173.3 days to determine nodal passage that is the place where eclipses can occur. These studies rely on Oppolzer's Eclipse Canon and Schram's Moon Phase Tables to verify eclipse occurrences. The newer canons of Jean Meeus and Bao-Lin Liu use decimal accuracy. What would be the effect of modern astronomical data on the previous studies and the Maya Eclipse Table? The study utilizes a general view of eclipses that includes eclipses not visible to the Maya. Lunar eclipses are …

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Scientists Are Urged To Look For Extraterrestrial Life Forms, Aldemaro Romero Jr., David Gilmore Jan 2007

Scientists Are Urged To Look For Extraterrestrial Life Forms, Aldemaro Romero Jr., David Gilmore

Publications and Research

No abstract provided.

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Thermal Properties Of Cubic Kta 1 X Nb X O 3 Crystals, X. P. Wang, J. Y. Wang, H. J. Zhang, Y. G. Yu, J. Wu, W. L. Gao, Robert I. Boughton Jan 2007

Thermal Properties Of Cubic Kta 1 X Nb X O 3 Crystals, X. P. Wang, J. Y. Wang, H. J. Zhang, Y. G. Yu, J. Wu, W. L. Gao, Robert I. Boughton

Physics and Astronomy Faculty Publications

Cubic potassium tantalite niobate KTa1−xNbxO3 KTN crystals of large size, good quality, and varying Nb concentration have been grown by the Czochralski method and their thermal properties have been systematically studied. The melting point, molar enthalpy of fusion, and molar entropy of fusion of the crystals were determined to be: 1536.9 K, 12 068.521 J mol−1, and 7.85 J K−1 mol−1 for KTa0.67Nb0.33O3; and 1520.61 K, 15 352.511 J mol−1, and 10.098 J K−1 mol−1 for KTa0.67Nb0.33O3, respectively. Based on the data, the Jackson factor was calculated to be 0.994f and 1.214f for KTa0.67Nb0.33O3 and KTa0.63Nb0.37O3, respectively. The thermal expansion …

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The Star Pile In Abell 545, R. Salinas, T. Richtler, M. J. West, Aaron J. Romanowsky, Y. Schuberth Jan 2007

The Star Pile In Abell 545, R. Salinas, T. Richtler, M. J. West, Aaron J. Romanowsky, Y. Schuberth

Faculty Publications

Context.Struble (1988, ApJ, 330, L25) found what appeared to be a cD halo without cD galaxy in the center of the galaxy cluster Abell 545. This remarkable feature has been passed almost unnoticed for nearly twenty years. Aims.Our goal is to review Struble's claim by providing a first (preliminary) photometric and spectroscopic analysis of this "star pile". Methods.Based on archival VLT-images and long-slit spectra obtained with Gemini-GMOS, we describe the photometric structure and measure the redshift of the star pile and of the central galaxy. Results.The star pile is indeed associated with Abell 545. Its velocity is higher by about …

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Numerical Methods For The Stochastic Landau-Lifshitz Navier-Stokes Equations, Alejandro Garcia, J. B. Bell, S. Williams Jan 2007

Numerical Methods For The Stochastic Landau-Lifshitz Navier-Stokes Equations, Alejandro Garcia, J. B. Bell, S. Williams

Faculty Publications

The Landau-Lifshitz Navier-Stokes (LLNS) equations incorporate thermal fluctuations into macroscopic hydrodynamics by using stochastic fluxes. This paper examines explicit Eulerian discretizations of the full LLNS equations. Several computational fluid dynamics approaches are considered (including MacCormack’s two-step Lax-Wendroff scheme and the piecewise parabolic method) and are found to give good results for the variance of momentum fluctuations. However, neither of these schemes accurately reproduces the fluctuations in energy or density. We introduce a conservative centered scheme with a third-order Runge-Kutta temporal integrator that does accurately produce fluctuations in density, energy, and momentum. A variety of numerical tests, including the random walk …

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The Pn.S Elliptical Galaxy Survey: Data Reduction, Planetary Nebula Catalog, And Basic Dynamics For Ngc 3379, N. G. Douglas, N. R. Napolitano, Aaron J. Romanowsky, L. Coccato, K. Kuijken, M. R. Merrifield, M. Arnaboldi, O. Gerhard, K. C. Freeman, H. R. Merrett, E. Noordermeer, M. Capaccioli Jan 2007

The Pn.S Elliptical Galaxy Survey: Data Reduction, Planetary Nebula Catalog, And Basic Dynamics For Ngc 3379, N. G. Douglas, N. R. Napolitano, Aaron J. Romanowsky, L. Coccato, K. Kuijken, M. R. Merrifield, M. Arnaboldi, O. Gerhard, K. C. Freeman, H. R. Merrett, E. Noordermeer, M. Capaccioli

Faculty Publications

We present results from Planetary Nebula Spectrograph (PN.S) observations of the elliptical galaxy NGC 3379 and a description of the data reduction pipeline. We detected 214 planetary nebulae, of which 191 are ascribed to NGC 3379 and 23 to the companion galaxy NGC 3384. Comparison with data from the literature shows that the PN.S velocities have an internal error of lesssim20 km s-1 and a possible offset of similar magnitude. We present the results of kinematic modeling and show that the PN kinematics is consistent with absorption-line data in the region where they overlap. The resulting combined kinematic data set, …

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Bianchi Identities And Weak Gravitational Lensing, Brian Keith Jan 2007

Bianchi Identities And Weak Gravitational Lensing, Brian Keith

Undergraduate Review

No abstract provided.

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Discovery Of Atomic And Molecular Mid-Infrared Emission Lines In Off-Nuclear Regions Of Ngc 1275 And Ngc 4696 With The Spitzer Space Telescope, R. M. Johnstone, N. A. Hatch, Gary J. Ferland, A. C. Fabian, C. S. Crawford, R. J. Wilman Jan 2007

Discovery Of Atomic And Molecular Mid-Infrared Emission Lines In Off-Nuclear Regions Of Ngc 1275 And Ngc 4696 With The Spitzer Space Telescope, R. M. Johnstone, N. A. Hatch, Gary J. Ferland, A. C. Fabian, C. S. Crawford, R. J. Wilman

Physics and Astronomy Faculty Publications

We present Spitzer high-resolution spectra of off-nuclear regions in the central cluster galaxies NGC 1275 and NGC 4696 in the Perseus and Centaurus clusters, respectively. Both objects are surrounded by extensive optical emission-line filamentary nebulae, bright outer parts of which are the targets of our observations. The 10–37 μm spectra show strong pure-rotational lines from molecular hydrogen revealing a molecular component to the filaments which has an excitation temperature of ∼300−400 K. The flux in the 0−0 S(1) molecular hydrogen line correlates well with the strength of the optical lines, having about 3 per cent of the Hα+[N II] emission. …

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Searches For Periodic Gravitational Waves From Unknown Isolated Sources And Scorpius X-1: Results From The Second Ligo Science Run, B. P. Abbott, R. Abbott, Mario C. Diaz, R. Grosso, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres Jan 2007

Searches For Periodic Gravitational Waves From Unknown Isolated Sources And Scorpius X-1: Results From The Second Ligo Science Run, B. P. Abbott, R. Abbott, Mario C. Diaz, R. Grosso, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

We carry out two searches for periodic gravitational waves using the most sensitive few hours of data from the second LIGO science run. Both searches exploit fully coherent matched filtering and cover wide areas of parameter space, an innovation over previous analyses which requires considerable algorithm development and computational power. The first search is targeted at isolated, previously unknown neutron stars, covers the entire sky in the frequency band 160–728.8 Hz, and assumes a frequency derivative of less than 4×10−10  Hz/s. The second search targets the accreting neutron star in the low-mass x-ray binary Scorpius X-1 and covers the frequency …

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External Control Of Electron Temperature In Ultra-Cold Plasmas, Roy O. Wilson Jan 2007

External Control Of Electron Temperature In Ultra-Cold Plasmas, Roy O. Wilson

Honors Theses

This thesis discusses progress towards achieving external control of the electron temperature and the Coulomb coupling parameter of ultra-cold plasmas. Using a Littman dye laser, we create the plasma by partially photoionizing a dense, cold sample of rubidium atoms in a magneto-optical trap (MOT). At a controllable time delay, we excite neutral atoms in the plasma to a specific Rydberg state using a narrow bandwidth pulsed dye laser. We have made progress towards optimizing and quantifying the achievable Rydberg atom density by using mm-wave spectroscopy to control the evolution of a cold dense Rydberg sample to plasma and have also …

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Reissner–Nordstrom Expansion, Emil Prodanov, Rossen Ivanov, Vesselin Gueorguiev Jan 2007

Reissner–Nordstrom Expansion, Emil Prodanov, Rossen Ivanov, Vesselin Gueorguiev

Articles

We propose a classical mechanism for the cosmic expansion during the radiation-dominated era, assuming the Universe as a two-component gas. The first component is the ultra-relativistic “standard” fraction described by an equation of state of an ideal quantum gas of massless particles. The second component consist of superheavy charged particles and their interaction with the “standard” fraction drives the expansion. This interaction is described by the Reissner–Nordstr¨om metric purely geometrically — the superheavy charged particles are modeled as zero-dimensional naked singularities which exhibit gravitational repulsion. The radius of a repulsive sphere, surrounding a naked singularity of charge Q, is inversely …

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Predicting Magnetopause Crossings At Geosynchronous Orbit During The Halloween Storms, Ramon E. Lopez, S. Hernandez, Michael J. Wiltberger, C.-L. Huang, E. I. Kepko, H. Spence, C. C. Goodrich, J. G. Lyon Jan 2007

Predicting Magnetopause Crossings At Geosynchronous Orbit During The Halloween Storms, Ramon E. Lopez, S. Hernandez, Michael J. Wiltberger, C.-L. Huang, E. I. Kepko, H. Spence, C. C. Goodrich, J. G. Lyon

Aerospace, Physics, and Space Science Faculty Publications

In late October and early November of 2003, the Sun unleashed a powerful series of events known as the Halloween storms. The coronal mass ejections launched by the Sun produced several severe compressions of the magnetosphere that moved the magnetopause inside of geosynchronous orbit. Such events are of interest to satellite operators, and the ability to predict magnetopause crossings along a given orbit is an important space weather capability. In this paper we compare geosynchronous observations of magnetopause crossings during the Halloween storms to crossings determined from the Lyon-Fedder-Mobarry global magnetohydrodynamic simulation of the magnetosphere as well to predictions of …

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Ion Escape From The High Latitude Magnetopause: Analysis Of Oxygen And Proton Dynamics In The Presence Of Magnetic Turbulence, Alexander L. Taktakishvili, G Zimbardo, Ermanno Amata, Sergey P. Savin, Antonella Greco, Pierluigi Veltri, Ramon E. Lopez Jan 2007

Ion Escape From The High Latitude Magnetopause: Analysis Of Oxygen And Proton Dynamics In The Presence Of Magnetic Turbulence, Alexander L. Taktakishvili, G Zimbardo, Ermanno Amata, Sergey P. Savin, Antonella Greco, Pierluigi Veltri, Ramon E. Lopez

Aerospace, Physics, and Space Science Faculty Publications

Recent Cluster observations of the vicinity of the high latitude magnetopause indicate the presence of beams of singly charged oxygen ions, which are of ionospheric origin. In this paper we examine the role of magnetic turbulence combined with a dc electric field across the magnetopause in causing the cross field transport of protons and of singly charged oxygen ions, by means of a kinetic test particle simulation. We find that the observed values of magnetosheath turbulence and electric fields can produce a substantial escape of the oxygen ions relative to protons. By varying the magnetic turbulence level in the simulation, …

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Asteroseismology Of The Pg 1159 Star Pg 0122+200, Jianning Fu, Matt A. Wood Jan 2007

Asteroseismology Of The Pg 1159 Star Pg 0122+200, Jianning Fu, Matt A. Wood

Aerospace, Physics, and Space Science Faculty Publications

Context. The variable pre-white dwarf PG 1159 stars (GW Vir) are g-mode non-radial pulsators. Asteroseismology puts strong constraints on their global parameters and internal structure. PG 0122+200 defines the red edge of the instability strip and its evolutionary timescale is predicted to be dominated by neutrino emission. Its study offers the opportunity to better understand the instability mechanism and to validate the physics of the neutrino production in dense plasma. Aims. To achieve such a goal requires determining precisely its fundamental parameters. This is the goal of this paper. Methods. We present new multi-site photometric observations obtained in 2001 and …

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Spectropolarimetric Survey Of Hydrogen-Rich White Dwarf Stars, Adéla Kawka, Stéphane Vennes, Gary D. Schmidt, Dayal T. Wickramasinghe, Rolf Koch Jan 2007

Spectropolarimetric Survey Of Hydrogen-Rich White Dwarf Stars, Adéla Kawka, Stéphane Vennes, Gary D. Schmidt, Dayal T. Wickramasinghe, Rolf Koch

Aerospace, Physics, and Space Science Faculty Publications

We have conducted a survey of 61 southern white dwarfs searching for magnetic fields using Zeeman spectropolarimetry. Our objective is to obtain a magnetic field distribution for these objects and, in particular, to find white dwarfs with weak fields. We found one possible candidate (WD 0310-688) that may have a weak magnetic field of -6.1 ±2.2 kG. Next, we determine the fraction and distribution of magnetic white dwarfs in the solar neighborhood and investigate the probability of finding more of these objects based on the current incidence of magnetism in white dwarfs within 20 pc of the Sun. We have …

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World Bank -Cpa Conflict: The Struggle To Define Human Rights And Development In The Philippines, Adam B. Robbins Jan 2007

World Bank -Cpa Conflict: The Struggle To Define Human Rights And Development In The Philippines, Adam B. Robbins

Honors Theses

This thesis analyzes the interactions between the World Bank (hereafter, the Bank) and the Cordillera Peoples Alliance (CPA), an indigenous and environmental advocacy group based in the Cordillera region of Luzon, in the Philippines. Using data gathered through both text-based and participatory research methods, I analyze the discursive relationship and violent confrontations between the two organizations. Conflicting development and human rights values cause the majority of these conflicts. I focus on how each organization enacts development and human rights, and how this leads to conflict. Ultimately, I intend for this thesis to offer practical guidance for the reader involved in …

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Mid-Infrared Galaxy Classification Based On Silicate Obscuration And Pah Equivalent Width, H. W. W. Spoon, J. A. Marshall, J. R. Houck, Moshe Elitzur, L. Hao, L. Armus, B. R. Brandl, V. Charmandaris Jan 2007

Mid-Infrared Galaxy Classification Based On Silicate Obscuration And Pah Equivalent Width, H. W. W. Spoon, J. A. Marshall, J. R. Houck, Moshe Elitzur, L. Hao, L. Armus, B. R. Brandl, V. Charmandaris

Physics and Astronomy Faculty Publications

We present a new diagnostic diagram for mid-infrared spectra of infrared galaxies based on the equivalent width of the 6.2 μm PAH emission feature and the strength of the 9.7 μm silicate feature. Based on the positions in this diagram, we classify galaxies into nine classes ranging from continuum-dominated AGN hot dust spectra and PAH-dominated starburst spectra to absorption-dominated spectra of deeply obscured galactic nuclei. We find that galaxies are systematically distributed along two distinct branches: one of AGN and starburst-dominated spectra and one of deeply obscured nuclei and starburst-dominated spectra. The separation into two branches likely reflects …

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Deep Mid-Infrared Silicate Absorption As A Diagnostic Of Obscuring Geometry Toward Galactic Nuclei, N. A. Levenson, M. M. Sirocky, L. Hao, H. W. W. Spoon, J. A. Marshall, Moshe Elitzur, J. R. Houck Jan 2007

Deep Mid-Infrared Silicate Absorption As A Diagnostic Of Obscuring Geometry Toward Galactic Nuclei, N. A. Levenson, M. M. Sirocky, L. Hao, H. W. W. Spoon, J. A. Marshall, Moshe Elitzur, J. R. Houck

Physics and Astronomy Faculty Publications

The silicate cross section peak near 10 μm produces emission and absorption features in the spectra of dusty galactic nuclei observed with the Spitzer Space Telescope. Especially in ultraluminous infrared galaxies, the observed absorption feature can be extremely deep, as IRAS 08572+3915 illustrates. A foreground screen of obscuration cannot reproduce this observed feature, even at a large optical depth. Instead, the deep absorption requires a nuclear source to be deeply embedded in a smooth distribution of material that is both geometrically and optically thick. In contrast, a clumpy medium can produce only shallow absorption or emission, which are …

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Quantization In Astrophysics, Brownian Motion, And Supersymmetry, Florentin Smarandache, Victor Christianto Jan 2007

Quantization In Astrophysics, Brownian Motion, And Supersymmetry, Florentin Smarandache, Victor Christianto

Branch Mathematics and Statistics Faculty and Staff Publications

The present book discusses, among other things, various quantization phenomena found in Astrophysics and some related issues including Brownian Motion. With recent discoveries of exoplanets in our galaxy and beyond, this Astrophysics quantization issue has attracted numerous discussions in the past few years. Most chapters in this book come from published papers in various peer-reviewed journals, and they cover different methods to describe quantization, including Weyl geometry, Supersymmetry, generalized Schrödinger, and Cartan torsion method. In some chapters Navier-Stokes equations are also discussed, because it is likely that this theory will remain relevant in Astrophysics and Cosmology While much of the …

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In-Situ And Simultaneous Measurements Of Size And Charge Distributions Of Dust On Mars: Instrumentation And Analysis, Praveen Kumar Srirama Jan 2007

In-Situ And Simultaneous Measurements Of Size And Charge Distributions Of Dust On Mars: Instrumentation And Analysis, Praveen Kumar Srirama

Theses and Dissertations

Martian dust characterization is important for minimizing the effects of abrasion, adhesion, corrosion, and damage to mission hardware, and also to reduce the effect on human health during future robotic and human exploratory missions. Characterizing the particle size and charge on Mars dust will help in the development of techniques for dust mitigation. Presently there is no miniature instrument which is capable of in-situ and real time measurements on Mars. In order to simultaneously analyze the particle size and charge of Mars dust, a Dust Particle Analyzer (DPA) has been developed and tested which is based on a Laser Doppler …

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Video-Tutorials For Tech Sign Vocabulary In Astronomy, Judy Egelston-Dodd, Simon Ting Jan 2007

Video-Tutorials For Tech Sign Vocabulary In Astronomy, Judy Egelston-Dodd, Simon Ting

Journal of Science Education for Students with Disabilities

This article describes the mediated American Sing Language (ASL) presentation of technical vocabulary and definitions within the context of a web-based astronomy course for first year students at the National Technical Institute for the Deaf at Rochester Institute of Technology (Rochester, NY). Deaf students showed achievement gains with fewer astronomy misconceptions. Also, student ratings of instructor ASL skill, as reported on the student rating system, were higher after students used the ASL vocabulary videos.

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