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Articles 7711 - 7740 of 9207

Full-Text Articles in Physical Sciences and Mathematics

Some Notes On Multiplicative Congruential Random Number Generators With Mersenne Prime Modulus 261-1., James Harris Jan 2003

Some Notes On Multiplicative Congruential Random Number Generators With Mersenne Prime Modulus 261-1., James Harris

Journal of the South Carolina Academy of Science

No abstract provided.


Embryogenesis In The Japanese Medaka, Oryzias Latipes, Laura Harris Harris, Lisa Sims, Roxann Stachiw Jan 2003

Embryogenesis In The Japanese Medaka, Oryzias Latipes, Laura Harris Harris, Lisa Sims, Roxann Stachiw

Journal of the South Carolina Academy of Science

No abstract provided.


Critical Thinking And Biology Instruction., David J. Stroup, John L. Frola Jan 2003

Critical Thinking And Biology Instruction., David J. Stroup, John L. Frola

Journal of the South Carolina Academy of Science

No abstract provided.


Intergalactic Globular Clusters, Michael J. West, Ted Von Hippel, Patrick Cote, Henry C. Ferguson, Michael D. Gregg, Andres Jordan, Ronald O. Marzke, Nial R. Tanvir Jan 2003

Intergalactic Globular Clusters, Michael J. West, Ted Von Hippel, Patrick Cote, Henry C. Ferguson, Michael D. Gregg, Andres Jordan, Ronald O. Marzke, Nial R. Tanvir

Publications

We confirm and extend our previous detection of a popula- tion of intergalactic globular clusters in Abell 1185, and report the first discovery of an intergalactic globular cluster in the nearby Virgo cluster of galaxies. The numbers, colors and luminosities of these objects can place constraints on their origin, which in turn may yield new insights to the evolution of galaxies in dense environments.


Sedimentological And Plant Taphonomic Evaluation Of The Early Middle Devonian Trout Valley Formation, Jonathan Allen Jan 2003

Sedimentological And Plant Taphonomic Evaluation Of The Early Middle Devonian Trout Valley Formation, Jonathan Allen

Honors Theses

The Trout Valley Formation of Emsian-Eifelian age, outcropped in Baxter State Park, Maine, consists offluvial and coastal deposits preserving early land plants. Massive, crudely bedded conglomerate represents deposits of proximal braided channels on an alluvial fan complex. Lithic sandstone bodies in channel-form geometries represent deposits of river channels draining the Acadian highlands whereas associated siltstones represent overbank deposits, intertidal flats, and tidal channels. Localized lenticular quartz arenites represent nearshore shelf bar deposits that were storm influenced. The majority of plant assemblages preserved mainly in siltstone lithologies are allochthonous and parautochthonous, with only one autochthonous assemblage identified in the sequence. Plant …


The Everchanging Pulsating White Dwarf Gd358, Souza Oliveira Kepler, Matt A. Wood, Nicole M. Silvestri, Thomas J. Ahrens Jan 2003

The Everchanging Pulsating White Dwarf Gd358, Souza Oliveira Kepler, Matt A. Wood, Nicole M. Silvestri, Thomas J. Ahrens

Aerospace, Physics, and Space Science Faculty Publications

We report 323 hours of nearly uninterrupted time series photometric observations of the DBV star GD 358 acquired with the Whole Earth Telescope (WET) during May 23rd to June 8th, 2000. We acquired more than 232 000 independent measurements. We also report on 48 hours of time-series photometric observations in Aug 1996. We detected the non-radial g-modes consistent with degree ℓ = 1 and radial order 8 to 20 and their linear combinations up to 6th order. We also detect, for the first time, a high amplitude ℓ = 2 mode, with a period of 796 s. In the 2000 …


Ulysses Cospin Observations Of Cosmic Rays And Solar Energetic Particles From The South Pole To The North Pole Of The Sun During Solar Maximum, Robert Bruce Mckibben, Ming Zhang Jan 2003

Ulysses Cospin Observations Of Cosmic Rays And Solar Energetic Particles From The South Pole To The North Pole Of The Sun During Solar Maximum, Robert Bruce Mckibben, Ming Zhang

Aerospace, Physics, and Space Science Faculty Publications

In 2000–2001 Ulysses passed from the south to the north polar regions of the Sun in the inner heliosphere, providing a snapshot of the latitudinal structure of cosmic ray modulation and solar energetic particle populations during a period near solar maximum. Observations from the COSPIN suite of energetic charged particle telescopes show that latitude variations in the cosmic ray intensity in the inner heliosphere are nearly non-existent near solar maximum, whereas small but clear latitude gradients were observed during the similar phase of Ulysses’ orbit near the 1994–95 solar minimum. At proton energies above ∼10 MeV and extending up to …


Lisa, Binary Stars, And The Mass Of The Graviton, Curt Cutler, William A. Hiscock, Shane L. Larson Jan 2003

Lisa, Binary Stars, And The Mass Of The Graviton, Curt Cutler, William A. Hiscock, Shane L. Larson

All Physics Faculty Publications

We extend and improve earlier estimates of the ability of the proposed LISA (Laser Interferometer Space Antenna) gravitational wave detector to place upper bounds on the graviton mass mg by comparing the arrival times of gravitational and electromagnetic signals from binary star systems. We show that the best possible limit on mg obtainable this way is ∼50 times better than the current limit set by solar system measurements. Among currently known, well-understood binaries, 4U1820-30 is the best for this purpose; LISA observations of 4U1820-30 should yield a limit ≈3-4 times better than the present solar system bound. AM …


Lisa Data Analysis: Source Identification And Subtraction, Neil J. Cornish, Shane L. Larson Jan 2003

Lisa Data Analysis: Source Identification And Subtraction, Neil J. Cornish, Shane L. Larson

All Physics Faculty Publications

The Laser Interferometer Space Antenna will operate as an AM-FM receiver for gravitational waves. For binary systems, the source location, orientation and orbital phase are encoded in the amplitude and frequency modulation. The same modulations spread a monochromatic signal over a range of frequencies, making it difficult to identify individual sources. We present a method for detecting and subtracting individual binary signals from a data stream with many overlapping signals.


Low-Flow Helmholtz Resonator For Molar Mass Detection, Brackman Amy, Amanda Kea, Kenneth Mcgill Jan 2003

Low-Flow Helmholtz Resonator For Molar Mass Detection, Brackman Amy, Amanda Kea, Kenneth Mcgill

The Corinthian

A simple apparatus was constructed for an undergraduate physical chemistry laboratory to determine a mathematical model of wavelike motion. The apparatus was assembled by attaching an airflow valve connected to a tank of argon gas to a GC column, thus creating regulated airflow. The air was manipulated to gently flow over a small sensitive microphone that was attached to an inexpensive resonator. A model will be developed to measure the speed of sound that will lead to the measurement of the molar mass.


Precision Measurement Of The Proton And Deuteron Spin Structure Functions G2 And Asymmetries A2, P. L. Anthony, R. G. Arnold, T. Averett, H. R. Band, N. Benmouna, W. Boeglin, H. Borel, P. E. Bosted, S. L. Bültmann, G. R. Court, C. E. Hyde-Wright, S. E. Kuhn, F. Sabatie, F. R. Wesselmann Jan 2003

Precision Measurement Of The Proton And Deuteron Spin Structure Functions G2 And Asymmetries A2, P. L. Anthony, R. G. Arnold, T. Averett, H. R. Band, N. Benmouna, W. Boeglin, H. Borel, P. E. Bosted, S. L. Bültmann, G. R. Court, C. E. Hyde-Wright, S. E. Kuhn, F. Sabatie, F. R. Wesselmann

Physics Faculty Publications

We have measured the spin struction functions g2(p) and g(2)(d) and the virtual photon asymmetries A(2)(p) and A(2)(d) over the kinetmatic range 0.02 less than or equal to x less than or equal to 0.8 and 0.7 less than or equal to Q2 less than or equal to 20 GeV2 by scattering 29.1 and 32.3 GeV longitudinally polarized electrons from transversely polarized NH3 and (LiD)-Li-6 targets. Our measured g2 approximately follows the twist-2 Wandzura-Wilczek calculation. The twist-3 reduced matrix elements d(2)(p) and d(2)(n) are less than two standard deviations from zero. The data are inconsistent with the Burkhardt-Cottingham …


The Neutron Charge Form Factor And Target Analyzing Powers From 3He (E→, E 'N) Scattering, J. Bermuth, P. Merle, C. Carasco, D. Baumann, R. Böhm, D. Bosnar, M. Ding, M. O. Distler, J. Friedrich, A. Klein Jan 2003

The Neutron Charge Form Factor And Target Analyzing Powers From 3He (E→, E 'N) Scattering, J. Bermuth, P. Merle, C. Carasco, D. Baumann, R. Böhm, D. Bosnar, M. Ding, M. O. Distler, J. Friedrich, A. Klein

Physics Faculty Publications

The charge form factor of the neutron has been determined from asymmetries measured in quasi-elastic 3He(e→, e 'n) at a momentum transfer of 0.67 (GeV/c)2. In addition, the target analyzing power, Ayo has been measured to study effects of final state interactions and mespn exchange currents.


Final State Interaction Effects In 3He (E→, E' P), C. Carasco, J. Bermuth, P. Merle, P. Bartsch, D. Baumann, R. Böhm, D. Bosnar, M. Ding, M. O. Distler, A. Klein Jan 2003

Final State Interaction Effects In 3He (E→, E' P), C. Carasco, J. Bermuth, P. Merle, P. Bartsch, D. Baumann, R. Böhm, D. Bosnar, M. Ding, M. O. Distler, A. Klein

Physics Faculty Publications

Asymmetries in quasi-elastic 3He(e→, e 'p) have been measured at a momentum transfer of 0.67 (GeV/c)2 and are compared to a calculation which takes into account relativistic kinematics in the final state and a relativistic one-body current operator. With an exact solution of the Faddeev equation for the 3He-ground state and an approximate treatment offinal state interactions in the continuum good agreement is found with the experimental data.


The Impact Of Pollution On Stellar Evolution Models, Aaron Dotter, Brian Chaboyer Jan 2003

The Impact Of Pollution On Stellar Evolution Models, Aaron Dotter, Brian Chaboyer

Dartmouth Scholarship

An approach is introduced for incorporating the concept of stellar pollution into stellar evolution models. The approach involves enhancing the metal content of the surface layers of stellar models. In addition, the surface layers of stars in the mass range of 0.5-2.0 M are mixed to an artificial depth motivated by observations of lithium abundance. The behavior of polluted stellar evolution models is explored assuming the pollution occurs after the star has left the fully convective pre-main-sequence phase. Stellar models polluted with a few Earth masses (M) of iron are significantly hotter than stars of the …


Histological Effect Of Ascocotyle Tenuicollis (Digenea: Heterophyidae) Metacercarial Infection On The Heart Of Fundulus Heteroclitus (Teleostei: Cyprinodontidae), Toni Hicks, Edna Steele Jan 2003

Histological Effect Of Ascocotyle Tenuicollis (Digenea: Heterophyidae) Metacercarial Infection On The Heart Of Fundulus Heteroclitus (Teleostei: Cyprinodontidae), Toni Hicks, Edna Steele

Journal of the South Carolina Academy of Science

No abstract provided.


South Carolina Statewide Science Safety Project., Linda Sinclair, Jack Gerlovich, Rahul A. Parsa Jan 2003

South Carolina Statewide Science Safety Project., Linda Sinclair, Jack Gerlovich, Rahul A. Parsa

Journal of the South Carolina Academy of Science

No abstract provided.


2002 & 2003 Annual Meeting Extended Abstracts Jan 2003

2002 & 2003 Annual Meeting Extended Abstracts

Journal of the South Carolina Academy of Science

No abstract provided.


Maternal And Sibling Influences On Seed Germination Of Aegilops Triuncialis Erin, Erin Scott, Andrew R. Dyer Jan 2003

Maternal And Sibling Influences On Seed Germination Of Aegilops Triuncialis Erin, Erin Scott, Andrew R. Dyer

Journal of the South Carolina Academy of Science

No abstract provided.


Scas Officers And Council Members 2003 - 2004 Jan 2003

Scas Officers And Council Members 2003 - 2004

Journal of the South Carolina Academy of Science

No abstract provided.


Measurement Of The Stochasticity Of Low-Latitude Geomagnetic Temporal Variations, Mark Anthony Reynolds, James A. Wanliss Jan 2003

Measurement Of The Stochasticity Of Low-Latitude Geomagnetic Temporal Variations, Mark Anthony Reynolds, James A. Wanliss

Publications

Ground magnetometer measurements of total magnetic field strength from 6 stations at low latitudes were analyzed using power spectrum and Hurst range scaling techniques. The Hurst exponents for most of these time-series were near 0.5, which indicates stochasticity, with the highest latitude stations exhibiting some persistence with Hurst exponents greater than 0.6. Although no definite correlations are evident, the relative increase of the Hurst exponent with latitude suggests the possibility that the underlying dynamics of the magnetosphere change with latitude. This result may help quantify the dynamics of the inner magnetosphere itself without the direct presence of the solar wind …


Spontaneous Magnetization Generated By Spin, Pulsating, And Planar Combustion Synthesis, Karen S. Martirosyan, J. R. Claycomb, G. Gogoshin, R. A. Yarbrough, J. H. Miller Jr., D. Luss Jan 2003

Spontaneous Magnetization Generated By Spin, Pulsating, And Planar Combustion Synthesis, Karen S. Martirosyan, J. R. Claycomb, G. Gogoshin, R. A. Yarbrough, J. H. Miller Jr., D. Luss

Physics and Astronomy Faculty Publications and Presentations

The motion of the high temperature front during combustion synthesis of ferrite materials generates residual magnetization in cylindrical product samples. The combustion wave created a current density of up to 10 A/cm2, which influenced the magnetization distribution. The measured peak magnetic field intensity was up to 8 mT. Qualitatively different magnetic field maps were generated in ferrite samples synthesized by different combustion modes. The average magnetization vector generated by either planar or pulsating combustion was oriented at a smaller angle with respect to the pellet axis ~f<45°! than those generated by spin combustion ~60°


Mode-Cleaning And Injection Optics Of The Gravitational-Wave Detector Geo600, S. Goßler, M. M. Casey, A. Grant, H. Grote, Volker Quetschke Jan 2003

Mode-Cleaning And Injection Optics Of The Gravitational-Wave Detector Geo600, S. Goßler, M. M. Casey, A. Grant, H. Grote, Volker Quetschke

Physics and Astronomy Faculty Publications and Presentations

The British–German interferometric gravitational-wave detector GEO600 uses two high-finesse triangular ring cavities of 8 m optical pathlength each, as an optical mode-cleaning system. The modecleaner system is housed in an ultrahigh-vacuum environment to avoid contamination of the optics and to minimize both the influence of refractive index variations of the air and acoustic coupling to the optics. To isolate the cavities from seismic noise, all optical components are suspended as double pendulums. These pendulums are damped at their resonance frequencies at the upper pendulum stage with magnet-coil actuators. A suspended reaction mass supports three coils matching magnets bonded onto the …


He Ii Reverberation In Active Galactic Nucleus Spectra, Mark C. Bottorff, Jack A. Baldwin, Gary J. Ferland, Jason W. Ferguson, Kirk T. Korista Dec 2002

He Ii Reverberation In Active Galactic Nucleus Spectra, Mark C. Bottorff, Jack A. Baldwin, Gary J. Ferland, Jason W. Ferguson, Kirk T. Korista

Physics and Astronomy Faculty Publications

This paper compares the observed reverberation response lags and the intensity ratios of the broad-line region (BLR) emission lines He II λ1640, He II λ4686, and C IV λ1549 with predictions. Published observations indicate that the He II λ1640 lag is 3 times shorter than the lags of He II λ4686 or C IV λ1549. Diverse models, however, do not reproduce this observation. Extensive improved numerical simulations of the hydrogenic isoelectronic sequence emission show that the He II spectrum remains especially simple, even in the central regions of a luminous quasar. Line trapping never builds up a significant population of …


A Planet At 5 Au Around 55 Cancri, Geoffrey W. Marcy, R. Paul Butler, Debra A. Fischer, Greg Laughlin, Steve S. Vogt, Gregory W. Henry, Dimitri Pourbaix Dec 2002

A Planet At 5 Au Around 55 Cancri, Geoffrey W. Marcy, R. Paul Butler, Debra A. Fischer, Greg Laughlin, Steve S. Vogt, Gregory W. Henry, Dimitri Pourbaix

Information Systems and Engineering Management Research Publications

We report precise Doppler-shift measurements of 55 Cancri (G8 V) obtained from 1989 to 2002 at Lick Observatory. The velocities reveal evidence for an outer planetary companion to 55 Cancri orbiting at 5.5 AU. The velocities also confirm a second, inner planet at 0.11 AU. The outer planet is the first extrasolar planet found that orbits near or beyond the orbit of Jupiter. It was drawn from a sample of ~50 stars observed with sufficient duration and quality to detect a giant planet at 5 AU, implying that such planets are not rare. The properties of this Jupiter analog may …


Controlling Laser High-Order Harmonic Generation Using Weak Counter-Propagating Light, Sergei Leonidovich Voronov Dec 2002

Controlling Laser High-Order Harmonic Generation Using Weak Counter-Propagating Light, Sergei Leonidovich Voronov

Theses and Dissertations

Laser high-order harmonic generation in the presence of relatively weak interfering light is investigated. The interfering pulses intersect the primary harmonic-generating laser pulse at the laser focus. The interfering light creates a standing intensity and phase modulation on the field, which disrupts microscopic phase matching and shuts down local high harmonic production. Suppression of the 23rd harmonic (by two orders of magnitude) is observed when a counter-propagating interfering pulse of light is introduced. A sequence of counter-propagating pulses can be used to shut down harmonic production in out-of-phase zones of the generating volume to achieve quasi phase matching. Harmonic emission …


The Morphology Of Nine Radio-Selected Faint Galaxies From Deep Hubble Space Telescope Imaging, Nathan D. Roche, James D. Lowenthal, David C. Koo Dec 2002

The Morphology Of Nine Radio-Selected Faint Galaxies From Deep Hubble Space Telescope Imaging, Nathan D. Roche, James D. Lowenthal, David C. Koo

Astronomy: Faculty Publications

Using the Hubble Space Telescope (HST) WFPC2 we perform deep I-band imaging of nine radio-selected [F(8.5 GHz) ≥ 14 μJy] faint galaxies from the Roche, Lowenthal & Koo (2002) sample. Two are also observed in V using HST STIS. Six of the galaxies have known redshifts, in the range 0.4 < z < 1.0. Radial intensity profiles indicate that seven are disc galaxies and two are bulge-dominated. Four of the six with redshifts have a high optical surface brightness in comparison with previous studies of disc galaxies at similar redshifts (e.g. Lilly et al. 1998). The HST imaging reveals that two of the nine galaxies are in close interacting pairs and another five show morphological evidence of recent interactions - two are very asymmetric (A ∼ 0.4) and three have large, luminous rings resembling the collisional starburst rings in the Cartwheel galaxy. For the two ring galaxies with redshifts, we measure ring radii of 7.05 and 10.0 h kpc, which suggest post-collision ages 0.1-0.2 Gyr. One has a fainter inner ring, like the original Cartwheel. The remaining two appear to be late-type barred galaxies and relatively undisturbed. Our HST imaging confirms the high incidence of interactions and dynamical disturbance in faint radio-selected galaxies, as reported by Windhorst et al. and Serjeant et al., for example. In the great majority of these galaxies the high radio luminosities are probably the result of interaction-triggered starbursts. However, one interacting galaxy is a very radio-luminous giant elliptical, with red V - I colours, a normal surface brightness and no evidence of star-forming regions, so its radio source is probably an obscured active galactic nucleus (AGN). The mixture of observed morphologies suggests that enhanced radio luminosities often persist to a late stage of interaction, i.e. at least ∼0.2 Gyr after the perigalactic encounter. asym 50 -1


Biaxial Strain-Modified Valence And Conduction Band Offsets Of Zinc-Blende Gan, Gap, Gaas, Inn, Inp, And Inas, And Optical Bowing Of Strained Epitaxial Ingan Alloys, Gus L. W. Hart, P. R. C. Kent, Alex Zunger Dec 2002

Biaxial Strain-Modified Valence And Conduction Band Offsets Of Zinc-Blende Gan, Gap, Gaas, Inn, Inp, And Inas, And Optical Bowing Of Strained Epitaxial Ingan Alloys, Gus L. W. Hart, P. R. C. Kent, Alex Zunger

Faculty Publications

Using density-functional calculations, we obtain the (001) biaxial strain dependence of the valence and conduction band energies of GaN, GaP, GaAs, InN, InP, and InAs. The results are fit to a convenient-to-use polynomial and the fits provided in tabular form. Using the calculated biaxial deformation potentials in large supercell empirical psuedopotential calculations, we demonstrate that epitaxial strain reduces the InGaN alloy bowing coefficient compared to relaxed bulk alloys.


An Observational Test Of The Spherical Model Atmospheres For The M Class Giants: The Case Of Δ2 Lyrae, Jeffrey J. Sudol, J. A. Benson, H. M. Dyck, M. Scholz Dec 2002

An Observational Test Of The Spherical Model Atmospheres For The M Class Giants: The Case Of Δ2 Lyrae, Jeffrey J. Sudol, J. A. Benson, H. M. Dyck, M. Scholz

Physics & Engineering Faculty Publications

No abstract provided.


Analysis Of Doppler-Broadened X-Ray Emission Line Profiles From Hot Stars, David H. Cohen, Roban Hultman Kramer , '03, S. P. Owocki Dec 2002

Analysis Of Doppler-Broadened X-Ray Emission Line Profiles From Hot Stars, David H. Cohen, Roban Hultman Kramer , '03, S. P. Owocki

Physics & Astronomy Faculty Works

We show how X-ray emission arising within an accelerating, expanding medium that also contains a source of continuum absorption generates line profiles of a characteristic shape. A simple, spherical wind model based on this picture provides good fits to the Chandra HETGS spectrum of the prototypical O star, Zeta Pup. We discuss the model, the fitting procedure and the determination of confidence limits on the model parameters, and our initial results for this star. The derived fit parameters are consistent with a generic wind-shock scenario for Zeta Pup, but there are several surprising aspects of the results, including a lower-than-expected …


The Tev Spectrum Of H1426+428, P. T. Reynolds, Et. Al. Nov 2002

The Tev Spectrum Of H1426+428, P. T. Reynolds, Et. Al.

Physical Sciences Publications

The BL Lac object H1426+428 was recently detected as a high-energy γ-ray source by the VERITAS collaboration (Horan et al.). We have reanalyzed the 2001 portion of the data used in the detection in order to examine the spectrum of H1426+428 above 250 GeV. We find that the time-averaged spectrum agrees with a power law of the shape






The statistical evidence from our data for emission above 2.5 TeV is 2.6 σ. At the 95% confidence level, the integral flux of H1426+428 above 2.5 TeV is larger than 3% of the corresponding flux from the Crab Nebula. The spectrum is …