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Articles 7021 - 7050 of 8870

Full-Text Articles in Astrophysics and Astronomy

Search For Gravitational Waves From Binary Black Hole Inspirals In Ligo Data, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres Jan 2006

Search For Gravitational Waves From Binary Black Hole Inspirals In Ligo Data, B. P. Abbott, R. Abbott, W. G. Anderson, Mario C. Diaz, Wm. R. Johnston, Soumya Mohanty, Soma Mukherjee, Cristina V. Torres

Physics & Astronomy Faculty Publications

We report on a search for gravitational waves from binary black hole inspirals in the data from the second science run of the LIGO interferometers. The search focused on binary systems with component masses between 3 and 20M⊙. Optimally oriented binaries with distances up to 1 Mpc could be detected with efficiency of at least 90%. We found no events that could be identified as gravitational waves in the 385.6 hours of data that we searched.

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Ferromagnetic Resonance Investigations On Ga0.965mn0.035as Film, S. Balascuta, X. Liu, D. V. Baxter, J. Carini, T. Wojtowicz, Y. Sasaki, J. Furdyna, Mircea Chipara Jan 2006

Ferromagnetic Resonance Investigations On Ga0.965mn0.035as Film, S. Balascuta, X. Liu, D. V. Baxter, J. Carini, T. Wojtowicz, Y. Sasaki, J. Furdyna, Mircea Chipara

Physics & Astronomy Faculty Publications

Ferromagnetic resonance studies of the temperature dependence of magnetic anisotropies in a Ga0.965Mn0.035As film between 5 and 40K are reported. The in-plane and out-of-the-plane angular dependences of the resonance field were analyzed within the Landau-Lifshitz-Gilbert approach. The second- and fourth-order magnetic anisotropy energies were derived. The temperature dependence of magnetization and of magnetic anisotropy were studied by superconducting quantum interference device and ferromagnetic resonance.

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Electrical Pulse Formation During High Temperature Reaction Between Ni And Al, Mona Setoodeh, Karen S. Martirosyan, Dan Luss Jan 2006

Electrical Pulse Formation During High Temperature Reaction Between Ni And Al, Mona Setoodeh, Karen S. Martirosyan, Dan Luss

Physics & Astronomy Faculty Publications

An electric voltage pulse (duration of about 2ms) with an amplitude of up to 0.6V was generated during the reaction between nickel and aluminum powders by a high temperature moving reaction front. The electrical signal formed during the initial stages of the combustion was annihilated before the moving front attained its maximum temperature. The voltage amplitude and combustion temperature depended on the particle size of the reactants as well as the Al to Ni ratio in the reactant mixture, and their largest values were attained for a mixture containing 27–31.5wt% Al. The combustion temperature increased when smaller Al particles were …

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The Lazarus Project. Ii. Spacelike Extraction With The Quasi-Kinnersley Tetrad, Manuela Campanelli, Bernard Kelly, Carlos O. Lousto Jan 2006

The Lazarus Project. Ii. Spacelike Extraction With The Quasi-Kinnersley Tetrad, Manuela Campanelli, Bernard Kelly, Carlos O. Lousto

Physics & Astronomy Faculty Publications

The Lazarus project was designed to make the most of limited 3D binary black-hole simulations, through the identification of perturbations at late times, and subsequent evolution of the Weyl scalar Ψ4 via the Teukolsky formulation. Here we report on new developments, employing the concept of the “quasi-Kinnersley” (transverse) frame, valid in the full nonlinear regime, to analyze late-time numerical space-times that should differ only slightly from Kerr. This allows us to extract the essential information about the background Kerr solution, and through this, to identify the radiation present. We explicitly test this procedure with full-numerical evolutions of Bowen-York data for …

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Relativistic Three-Body Effects In Black Hole Coalescence, Manuela Campanelli, Miranda Dettwyler, Mark Hannam, Carlos O. Lousto Jan 2006

Relativistic Three-Body Effects In Black Hole Coalescence, Manuela Campanelli, Miranda Dettwyler, Mark Hannam, Carlos O. Lousto

Physics & Astronomy Faculty Publications

Three-body interactions are expected to be common in globular clusters and in galactic cores hosting supermassive black holes. We consider an equal-mass binary black hole system in the presence of a third black hole. Using numerically generated binary black hole initial data sets, and first and second-order post-Newtonian (1PN and 2PN) techniques, we find that the presence of the third black hole has nonnegligible relativistic effects on the location of the binary’s innermost stable circular orbit (ISCO), and that these effects arise at 2PN order. For a stellar-mass black hole binary in orbit about a supermassive black hole, the massive …

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A New Color-Magnitude Diagram For Palomar 11, Matthew S. Lewis, W. M. Liu, N. E. Q. Paust, Brian Chaboyer Jan 2006

A New Color-Magnitude Diagram For Palomar 11, Matthew S. Lewis, W. M. Liu, N. E. Q. Paust, Brian Chaboyer

Dartmouth Scholarship

We present new photometry for the Galactic thick-disk globular cluster Palomar 11 extending well past the main-sequence turnoff in the V and I bands. This photometry shows noticeable, but depleted, red giant and subgiant branches. The difference in magnitude between the red horizontal branch (red clump) and the subgiant branch is used to determine that Palomar 11 has an age of 10.4 ± 0.5 Gyr. The red clump is used to derive a distance d⊙ = 14.3 ± 0.4 kpc and a mean cluster reddening of E(V - I) = 0.40 ± 0.03. There is differential …

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Ubvi Ccd Photometry Of The Old Open Cluster Berkeley 17, Zosia A. C. Krusberg, Brian Chaboyer Jan 2006

Ubvi Ccd Photometry Of The Old Open Cluster Berkeley 17, Zosia A. C. Krusberg, Brian Chaboyer

Dartmouth Scholarship

Photometric UBVI CCD photometry is presented for NGC 188 and Berkeley 17. Color-magnitude diagrams (CMDs) are constructed and reach well past the main-sequence turnoff for both clusters. Cluster ages are determined by means of isochrone fitting to the cluster CMDs. These fits are constrained to agree with spectroscopic metallicity and reddening estimates. Cluster ages are determined to be 7.0 ± 0.5 Gyr for NGC 188 and 10.0 ± 1.0 Gyr for Berkeley 17, where the errors refer to uncertainties in the relative age determinations. These ages are compared to the ages of relatively metal-rich inner halo/thick-disk globular clusters and other …

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High-Temperature Calcium Vapor Cell For Spectroscopy On The 4s2 1s0-4s4p 3p1 Intercombination Line, Christopher J. Erickson, Brian Neyenhuis, Dallin S. Durfee Dec 2005

High-Temperature Calcium Vapor Cell For Spectroscopy On The 4s2 1s0-4s4p 3p1 Intercombination Line, Christopher J. Erickson, Brian Neyenhuis, Dallin S. Durfee

Faculty Publications

We have demonstrated a high-temperature vapor cell for absorption spectroscopy on the Ca intercombination line. The cell uses a dual-chamber design to achieve the high temperatures necessary for an optically dense vapor while avoiding the necessity of high-temperature vacuum valves and glass-to-metal seals. We have observed over 50% absorption in a single pass through the cell. Although pressure broadening in the cell prevented us from performing saturated-absorption spectroscopy, the broadening resulted in higher signal-to-noise ratios by allowing us to probe the atoms with intensities much greater than the 0.2µW/cm2 saturation intensity of the unbroadened transition. The techniques presented in this …

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The Dust Cloud Around The White Dwarf G29-38, William T. Reach, Ted Von Hippel, Et Al. Dec 2005

The Dust Cloud Around The White Dwarf G29-38, William T. Reach, Ted Von Hippel, Et Al.

Publications

We present new observations of the white dwarf G29-38 with the camera (4.5 and 8 μm), photometer (24 μm), and spectrograph (5.5-14 μm) of the Spitzer Space Telescope. This star has an exceptionally large infrared excess, amounting to 3% of the bolometric luminosity. The spectral energy distribution (SED) has a continuum peak around 4.5 μm and a 9-11 μm emission feature 1.25 times brighter than the continuum. A mixture of amorphous olivine and a small amount of forsterite in an emitting region 1-5 R☉ from the star can reproduce the shape of the 9-11 μm feature. The SED …

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Nonmetal Ordering In Tic1-Xnx: Ground-State Structure And The Effects Of Finite Temperature, Gus L. W. Hart, Brian Kolb Dec 2005

Nonmetal Ordering In Tic1-Xnx: Ground-State Structure And The Effects Of Finite Temperature, Gus L. W. Hart, Brian Kolb

Faculty Publications

The TiC1-xNx system has long been prized in industry because of its desirable thermodynamic and hardness characteristics. Previous studies have not produced comprehensive results describing the ordering tendencies of TiC1-xNx at any temperature. We apply the mixed-basis cluster expansion and Monte Carlo methods to the problem and find a fascinating array of ground-state structures occurring at precise nitrogen-concentration intervals of ∆x=1/16 and related to each other by simple (201) quasisuperlattice motifs. Thermodynamic Monte Carlo results indicate that the critical ordering temperatures at all concentrations are well below room temperature. short-range ordering develops at T ≈ 800 K and exhibits the …

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Electromagnetism In Gravitational Collapse, Craig Ernest Skinfill Dec 2005

Electromagnetism In Gravitational Collapse, Craig Ernest Skinfill

Theses and Dissertations

A numerical approach to including electromagnetism with general relativity is developed using GRAXI as a starting point. We develop a mathematical model describing electromagnetism coupled to a scalar field in an evolving axisymmetric spacetime. As there are numerous formulations of electromagnetism, we evalute different formulations in a limited flat space case. The full curved space system is then developed, using the flat case as a guide to implementing electromagnetism. This model is then implemented using GRAXI as a code base.

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A Multisite Photometric Campaign On The Pre-Main-Sequence ₰ Delta Scuti Pulsator Ip Per, V. Ripepi, T. D. Oswalt, S. Bernabei, M. Marconi, Et Al. Dec 2005

A Multisite Photometric Campaign On The Pre-Main-Sequence ₰ Delta Scuti Pulsator Ip Per, V. Ripepi, T. D. Oswalt, S. Bernabei, M. Marconi, Et Al.

Publications

We present the results of a photometric multisite campaign on the δ Scuti Pre-Main-Sequence star IP Per. Nine telescopes have been involved in the observations, with a total of about 190 h of observations over 38 nights. Present data confirms the multiperiodic nature of this star and leads to the identification of at least nine pulsational frequencies. Comparison with the predictions of linear non-adiabatic radial pulsation models allowed us to identify only five of the nine observed frequencies, and to constrain the position of IP Per in the HR diagram. The latter is in good agreement with the empirical determination …

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Ultracold Neutral Plasma Expansion In Two Dimensions, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson Dec 2005

Ultracold Neutral Plasma Expansion In Two Dimensions, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson

Faculty Publications

An isothermal model of ultracold neutral plasma expansion is extended to systems without spherical symmetry. It is used to interpret new fluorescence measurements on ultracold neutral calcium plasmas. For a self-similar expansion, the fluid equations are solved both analytically and numerically. The density and velocity solutions are used to predict fluorescence signals induced by a laser beam weakly focused into the plasma. Despite the simplicity of the model, predicted fluorescence signals reproduce major features of the experimental data

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Longitudinal Magnetic Field Changes Accompanying Solar Flares, Jeffrey J. Sudol, J. W. Harvey Dec 2005

Longitudinal Magnetic Field Changes Accompanying Solar Flares, Jeffrey J. Sudol, J. W. Harvey

Physics & Engineering Faculty Publications

No abstract provided.

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Iso Observations Of The Interacting Galaxy Markarian 297 - With The Powerful Supernova Remnant 1982aa, Niall Smith, Et. Al. Dec 2005

Iso Observations Of The Interacting Galaxy Markarian 297 - With The Powerful Supernova Remnant 1982aa, Niall Smith, Et. Al.

Blackrock Castle Observatory Publications

Markarian (Mkn) 297 is a complex system comprised of two interacting galaxies that has been modelled with a variety of scenarios. Observations of this system were made with the Infrared Space Observatory (ISO) using the ISOCAM, ISOPHOT and LWS instruments. ISOCAM maps at 6.7 µm, 7.7 µm, 12 µm and 14.3 µm are presented which, together with PHT-S spectrometry of the central interacting region, probe the dust obscured star formation and the properties of the organic dust. The ISOCAM observations reveal that the strongest emission in the four bands is at a location completely unremarkable at visible and near-IR (e.g. …

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Numerical Modeling Of Hohlraum Radiation Conditions: Spatial And Spectral Variations Due To Sample Position, Beam Pointing, And Hohlraum Geometry, David H. Cohen, O. L. Landen, J. J. Macfarlane Dec 2005

Numerical Modeling Of Hohlraum Radiation Conditions: Spatial And Spectral Variations Due To Sample Position, Beam Pointing, And Hohlraum Geometry, David H. Cohen, O. L. Landen, J. J. Macfarlane

Physics & Astronomy Faculty Works

View-factor simulations are presented of the spatially varying radiation conditions inside double-ended gold Hohlraums and single-ended gold Hohlraums ('' halfraums '') used in inertial confinement fusion and high-energy density physics experiments [J. Lindl, Phys. Plasmas 11, 339 (2004); M. D. Rosen, Phys. Plasmas 3, 1803 (1996)]. It is shown that in many circumstances, the common assumption that the Hohlraum '' drive '' can be characterized by a single temperature is too simplistic. Specifically, the radiation conditions seen by an experimental package can differ significantly from the wall reemission measured through diagnostic holes or laser entrance holes (LEHs) by absolutely calibrated …

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Galactic Cosmic-Ray Modulation Using A Solar Minimum Mhd Heliosphere: A Stochastic Particle Approach, Bryan M. Ball, Ming Zhang, Hamid K. Rassoul, Timur J. Linde Dec 2005

Galactic Cosmic-Ray Modulation Using A Solar Minimum Mhd Heliosphere: A Stochastic Particle Approach, Bryan M. Ball, Ming Zhang, Hamid K. Rassoul, Timur J. Linde

Aerospace, Physics, and Space Science Faculty Publications

An example of Galactic cosmic-ray modulation in a fully three-dimensional heliosphere is presented here. We use a stochastic particle method to solve for modulation without requiring symmetric boundaries or fields. We include all typical modulation terms, including full three-dimensional drift. We have applied this to an MHD heliosphere appropriate for solar minimum conditions. This field includes nonradial solar wind velocity components, as well as a built-in nonspherical termination shock. Parameters that are of interest in modulation can be analyzed in detail, particularly the momentum change of cosmic rays during their transport through the heliosphere. We show radial profiles of modulation …

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Neutrosophic Methods In General Relativity, Florentin Smarandache, Dmitri Rabounski, Larissa Borissova Dec 2005

Neutrosophic Methods In General Relativity, Florentin Smarandache, Dmitri Rabounski, Larissa Borissova

Branch Mathematics and Statistics Faculty and Staff Publications

In this work the authors apply concepts of Neutrosophic Logic to the General Theory of Relativity to obtain a generalisation of Einstein’s fourdimensional pseudo-Riemannian differentiable manifold in terms of Smarandache Geometry (Smarandache manifolds), by which new classes of relativistic particles and non-quantum teleportation are developed. Fundamental features of Neutrosophic Logic are its denial of the Law of Excluded Middle, and open (or estimated) levels of truth, falsity and indeterminancy. Both Neutrosophic Logic and Smarandache Geometry were invented some years ago by one of the authors (F. Smarandache). The application of these purely mathematical theories to General Relativity reveals hitherto unknown …

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Multivalued Logic, Neutrosophy And Schrodinger Equation, Florentin Smarandache, Victor Christianto Dec 2005

Multivalued Logic, Neutrosophy And Schrodinger Equation, Florentin Smarandache, Victor Christianto

Branch Mathematics and Statistics Faculty and Staff Publications

This book was intended to discuss some paradoxes in Quantum Mechanics from the viewpoint of Multi-Valued-logic pioneered by Lukasiewicz, and a recent concept Neutrosophic Logic. Essentially, this new concept offers new insights on the idea of ‘identity’, which too often it has been accepted as given. Neutrosophy itself was developed in attempt to generalize Fuzzy-Logic introduced by L. Zadeh. While some aspects of theoretical foundations of logic are discussed, this book is not intended solely for pure mathematicians, but instead for physicists in the hope that some of ideas presented herein will be found useful. The book is motivated by …

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The Opacity Of Spiral Galaxy Disks. V. Dust Opacity, Hi Distributions And Sub-Mm Emission., Benne W. Holwerda, R. A. Gonzalez, Ronald J. Allen, P. C. Van Der Kruit Dec 2005

The Opacity Of Spiral Galaxy Disks. V. Dust Opacity, Hi Distributions And Sub-Mm Emission., Benne W. Holwerda, R. A. Gonzalez, Ronald J. Allen, P. C. Van Der Kruit

Faculty and Staff Scholarship

The opacity of spiral galaxy disks, from counts of distant galaxies, is compared to HI column densities. The opacity measurements are calibrated using the “Synthetic Field Method” from González et al. (1998, ApJ, 506, 152), Holwerda et al. (2005a, AJ, 129, 1381). When compared for individual disks, the HI column density and dust opacity do not seem to be correlated as HI and opacity follow different radial profiles. To improve statistics, an average radial opacity profile is compared to an average HI profile. Compared to dust-to-HI estimates from the literature, more extinction is found in this profile. This difference may …

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The Opacity Of Spiral Galaxy Disks Vii. The Accuracy Of Galaxy Counts As An Extinction Probe., Benne W. Holwerda, R. A. Gonzalez, Ronald J. Allen, P. C. Van Der Kruit Dec 2005

The Opacity Of Spiral Galaxy Disks Vii. The Accuracy Of Galaxy Counts As An Extinction Probe., Benne W. Holwerda, R. A. Gonzalez, Ronald J. Allen, P. C. Van Der Kruit

Faculty and Staff Scholarship

The "Synthetic Field Method" (SFM) was introduced by González et al. (1998, ApJ, 506, 152) to calibrate numbers of distant galaxies as a probe of extinction in a foreground spiral disk. González et al. (2003, AJ, 125, 1182) studied the effect of the foreground disk on these numbers using simulations of current and future instruments for fields in the LMC, M 31 and NGC 4536, a galaxy in Virgo. They concluded that: (1) the brighter centers of disks were unsuitable; (2) the granularity of the disk at a fixed surface brightness is the limiting factor in the detection of distant …

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The Opacity Of Spiral Galaxy Disks. Vi. Extinction, Stellar Light And Color., Benne W. Holwerda, R. A. Gonzalez, P. C. Van Der Kruit, R. J. Allen Dec 2005

The Opacity Of Spiral Galaxy Disks. Vi. Extinction, Stellar Light And Color., Benne W. Holwerda, R. A. Gonzalez, P. C. Van Der Kruit, R. J. Allen

Faculty and Staff Scholarship

In this paper we explore the relation between dust extinction and stellar light distribution in disks of spiral galaxies. Extinction influences our dynamical and photometric perception of disks, since it can distort our measurement of the contribution of the stellar component. To characterize the total extinction by a foreground disk, González et al. (1998, ApJ, 506, 152) proposed the "Synthetic Field Method" (SFM), which uses the calibrated number of distant galaxies seen through the foreground disk as a direct indication of extinction. The method is described in González et al. (1998, ApJ, 506, 152) and Holwerda et al. (2005a, AJ, …

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Measuring The Evolution Of The Most Stable Optical Clock G 117-B15a, S. O. Kepler, Ted Von Hippel, Et Al. Dec 2005

Measuring The Evolution Of The Most Stable Optical Clock G 117-B15a, S. O. Kepler, Ted Von Hippel, Et Al.

Publications

We report our measurement of the rate of change of period with time () for the 215 s periodicity in the pulsating white dwarf G 117-B15A, the most stable optical clock known. After 31 years of observations, we have finally obtained a 4 σ measurement observed = (4.27 ± 0.80) × 10-15 s s-1. Taking into account the proper-motion effect of proper = (7.0 ± 2.0) × 10-16s s-1, we obtain a rate of change of period with time of = (3.57 ± 0.82) × 10-15 s s-1. This value is consistent with the cooling rate in our white dwarf …

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Book Review: Stargazer: The Life And Times Of The Telescope, T. D. Oswalt Dec 2005

Book Review: Stargazer: The Life And Times Of The Telescope, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of Stargazer : the Life and Times of the Telescope by Fred Watson. Da Capo, 2004 342p, 0306814323 $24.95

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Fluorescence Measurements Of Expanding Strongly Coupled Neutral Plasmas, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson Nov 2005

Fluorescence Measurements Of Expanding Strongly Coupled Neutral Plasmas, E. A. Cummings, J. E. Daily, Dallin S. Durfee, Scott D. Bergeson

Faculty Publications

We report new detailed density profile measurements in expanding strongly coupled neutral calcium plasmas. Using laser-induced fluorescence techniques, we determine plasma densities in the range of 10^5 to 10^9 cm^-3 with a time resolution limit as small as 7 ns. Strong coupling in the plasma ions is inferred directly from the fluorescence signals. Evidence for strong coupling at late times is presented, confirming a recent theoretical result.

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Acoustics Of The Salt Lake Tabernacle: Characterization And Study Of Spatial Variation, Sarah Rollins Nov 2005

Acoustics Of The Salt Lake Tabernacle: Characterization And Study Of Spatial Variation, Sarah Rollins

Theses and Dissertations

In order to preserve the acoustics of the Salt Lake Tabernacle after the seismic renovation of 2005-2006, it was necessary to characterize these acoustics immediately preceding the renovation. This thesis discusses the characterization process that began with the measurement of hundreds of impulse responses for five different source positions and several receiver locations throughout the hall seating areas. The acoustics were further characterized by deriving various parameters from these responses that correlate with subjective preferences for music and speech. Impulse responses were also generated by a CATT-Acoustic™ computer model of the Tabernacle for the same purpose. The parameter values were …

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Dq Herculis In Profile: Whole Earth Telescope Observations And Smoothed Particle Hydrodynamics Simulations Of An Edge-On Cataclysmic Variable System, Matt A. Wood Nov 2005

Dq Herculis In Profile: Whole Earth Telescope Observations And Smoothed Particle Hydrodynamics Simulations Of An Edge-On Cataclysmic Variable System, Matt A. Wood

Aerospace, Physics, and Space Science Faculty Publications

The old nova DQ Herculis was the Whole Earth Telescope Northern Hemisphere target for the 1997 July campaign and was observed on four nights with the SARA 0.9 m telescope during 2003 June. We present updated ephemerides for the eclipse and 71 s timings. The Fourier transform displays power at the presumed white dwarf spin period of 71.0655 s, but no significant power at either 142 or 35.5 s. The mean pulsed light curve is obtained by folding on the orbital period modulus the mean ephemeris of the 71 s period, and from this we calculate an O - C …

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The Compression Of Dark Matter Halos By Baryonic Infall, Stacy S. Mcgaugh Nov 2005

The Compression Of Dark Matter Halos By Baryonic Infall, Stacy S. Mcgaugh

Faculty Scholarship

The initial radial density profiles of dark matter halos are laid down by gravitational collapse in hierarchical structure formation scenarios and are subject to further compression as baryons cool and settle to the halo centers. Here we describe an explicit implementation of the algorithm, originally developed by Young, to calculate changes to the density profile as the result of adiabatic infall in a spherical halo model. Halos with random motion are more resistant to compression than are those in which random motions are neglected, which is a key weakness of the simple method widely employed. Young's algorithm results in density …

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Sun In The Spectroscopic Binary Im Pegasi, The Guide Star For The Gravity Probe B Mission, Stephen C. Marsden, Svetlana Berdyugina, Jean-Francois Donati, Joel A. Eaton, Michael H. Williamson, Ilya Ilyin, Debra A. Fischer, Melesio Muñoz, Howard Isaacson, M. I. Ratner, Meïr Semel, Pascal Petit, Brad D. Carter Nov 2005

Sun In The Spectroscopic Binary Im Pegasi, The Guide Star For The Gravity Probe B Mission, Stephen C. Marsden, Svetlana Berdyugina, Jean-Francois Donati, Joel A. Eaton, Michael H. Williamson, Ilya Ilyin, Debra A. Fischer, Melesio Muñoz, Howard Isaacson, M. I. Ratner, Meïr Semel, Pascal Petit, Brad D. Carter

Information Systems and Engineering Management Research Publications

We present the first detection of the secondary of the spectroscopic binary system IM Pegasi (HR 8703), the guide star for the NASA-Stanford relativity gyroscope mission Gravity Probe B. In support of this mission, high-resolution echelle spectra of IM Peg have been obtained on an almost nightly basis. Applying the technique of least-squares deconvolution, we achieve very high signal-to-noise ratio line profiles and detect the orbit of the secondary of the system. Combining almost 700 new radial velocity measurements of both the primary and secondary of the system with previous measurements, we derive improved orbital parameters of the IM Peg …

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Pumping Or Mixing System Using A Levitating Magnetic Element, Aexandre N. Terentiev Nov 2005

Pumping Or Mixing System Using A Levitating Magnetic Element, Aexandre N. Terentiev

Physics and Astronomy Faculty Patents

A system capable of pumping or mixing fluids using a rotating magnetic element or bearing levitated by a cold superconducting element is disclosed.

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