Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- South Carolina (20)
- United States (15)
- Stars: abundances (6)
- Community leadership (4)
- Economic conditions (4)
-
- Special Report (4)
- Working Paper Series (4)
- Abundances (2)
- Binaries: spectroscopic (2)
- Duncan (S.C.) (2)
- Globular clusters: individual (M92) (2)
- Lyman (S.C.) (2)
- Nuclear reactions (2)
- Nucleosynthesis (2)
- STARS: EVOLUTION (2)
- Stars: Evolution (2)
- Stars: evolution (2)
- Supernovae: general (2)
- Wellford (S.C.) (2)
- African Americans (1)
- Agriculture (1)
- Aiken County (S.C.) (1)
- Amphidiploid (1)
- Berkeley County (S.C.) (1)
- Bosnia and Herzegovina (Bosnia and Herzegovina : Federation) (1)
- Central Pacolet (S.C.) (1)
- Chaetotaxy (1)
- China (1)
- Chromosome doubling (1)
- Cities and towns--Growth (1)
Articles 1 - 30 of 71
Full-Text Articles in Entire DC Network
Impact Of Business Incentives On General Revenue: Projected Fiscal Costs, 1998 December 31, Daniel V. Rainey
Impact Of Business Incentives On General Revenue: Projected Fiscal Costs, 1998 December 31, Daniel V. Rainey
Publications
No abstract provided.
State Revenue: Projections To 2010, 1998 December 31, Holley Hewitt Ulbrich
State Revenue: Projections To 2010, 1998 December 31, Holley Hewitt Ulbrich
Publications
No abstract provided.
State Expenditures: Projections To 2010, 1998 December 31, Daniel V. Rainey
State Expenditures: Projections To 2010, 1998 December 31, Daniel V. Rainey
Publications
No abstract provided.
Long-Wavelength Collective Excitations In A Two-Dimensional Spin-Polarized Electron Gas: A Phenomenological Theory, D C. Marinescu, J J. Quinn
Long-Wavelength Collective Excitations In A Two-Dimensional Spin-Polarized Electron Gas: A Phenomenological Theory, D C. Marinescu, J J. Quinn
Publications
The dispersion relations of the collective excitations induced in a 2D spin-polarized electron gas are derived within the framework of the Landau-Silin theory applied to a two-component Fermi liquid. The quasiparticle interaction is described by spin-dependent coefficients, which are parametric functions of the initial degree of polarization. The motion of the low-energy excitations satisfies a semiclassical transport equation solved consistently with the Maxwell equations for the electromagnetic field produced by spin and charge fluctuations. The long-wavelength limit of the self-sustained oscillations is analyzed as a function of the initial degree of polarization of the system, preset by a dc magnetic …
The Economic Situation, 1998 December, Bruce Yandle
The Economic Situation, 1998 December, Bruce Yandle
Publications
Quarterly report on the economic situation of the United States and South Carolina.
Challenges Of Managing A Rapidly Growing And Changing County, 1998 November 19, Jim Rozier
Challenges Of Managing A Rapidly Growing And Changing County, 1998 November 19, Jim Rozier
Publications
Presented at the Tenth Annual Harris Page Smith Lecture in Local Government.
The Diffuse Gamma-Ray Background From Supernovae, Dieter H. Hartmann, K. Watanabe, M. D. Leising, L.-S. The
The Diffuse Gamma-Ray Background From Supernovae, Dieter H. Hartmann, K. Watanabe, M. D. Leising, L.-S. The
Publications
The diffuse extragalactic γ-ray background in the MeV region is believed to be due to photons from radioactivity produced in supernovae throughout the history of galaxies in the universe. In particular, γ-ray line emission from the decay chain 56Ni → 56Co → 56Fe provides the dominant photon source (Clayton & Silk 1969). Although iron synthesis occurs in all types of supernovae, the contribution to the background is dominated by Type Ia events due to their higher photon escape probabilities. Estimates of the star formation history in the universe suggest a rapid increase by a factor ∼ 10 from the present …
Collective Excitations In An Asymmetrically Spin-Polarized Quantum Well, D C. Marinescu, J J. Quinn
Collective Excitations In An Asymmetrically Spin-Polarized Quantum Well, D C. Marinescu, J J. Quinn
Publications
We present a phenomenological picture for the many-body excitations of a two-dimensional electron gas in a quantum well spin polarized by a dc magnetic field at an angle with the axis of the well. In the framework of the Landau theory of charged Fermi liquids, we determine the frequencies of collective modes by solving a transport equation for quasiparticles in the local electromagnetic field associated with the charge- and spin-density fluctuations. In the long-wavelength limit, analytic solutions for (qជ) are obtained as functions of the degree of spin polarization and of the angle .
A Statistical Treatment Of The Gamma-Ray Burst "No Host Galaxy" Problem: Ii. Energies Of Standard Candle Bursts, Dieter H. Hartmann, David L. Band, Bradley E. Schaefer
A Statistical Treatment Of The Gamma-Ray Burst "No Host Galaxy" Problem: Ii. Energies Of Standard Candle Bursts, Dieter H. Hartmann, David L. Band, Bradley E. Schaefer
Publications
With the discovery that the afterglows after some bursts are coincident with faint galaxies, the search for host galaxies is no longer a test of whether bursts are at cosmological distances, but rather a test of particular cosmological models. The methodology we developed to investigate the original “no host galaxy” problem is equally valid for testing different cosmological models, and is applicable to the galaxies coincident with optical transients. We apply this methodology to a family of models where we vary the total energy of standard candle bursts. We find that total isotropic energies of E < 2 ×10^52 erg are ruled out while E ∼ 10^53 erg is favored.
Detection Of Silver In Metal-Poor Stars, James L. Crawford, Christopher Sneden, Jeremy R. King, Ann M. Boesgaard, Contantine P. Deliyannis
Detection Of Silver In Metal-Poor Stars, James L. Crawford, Christopher Sneden, Jeremy R. King, Ann M. Boesgaard, Contantine P. Deliyannis
Publications
The resonance lines of neutral silver appearing at 3280, 3382 Å in the near-ultraviolet spectral region have been identified on Keck I HIRES spectra of four halo stars with metallicities -1.3 ≥ [Fe/H] ≥ -2.2. This represents the first detection in metal-poor stars of an element in the atomic number range 41 ≤ Z ≤ 55. The mean relative silver abundance is [Ag/Fe] +0.2, with little star-to-star variation. Silver abundance upper limits in three other metal-poor stars are consistent with this mean value. The modest overabundance of silver is similar to the overabundances in this metallicity range exhibited by other …
Scots-Irish In The Carolinas, 1998 October 8, Billy Kennedy
Scots-Irish In The Carolinas, 1998 October 8, Billy Kennedy
Publications
No abstract provided.
Does South Carolina Hold The Moral Ground In Lawsuits Against Tobacco Companies?, 1998 October, Clinton H. Whitehurst Jr.
Does South Carolina Hold The Moral Ground In Lawsuits Against Tobacco Companies?, 1998 October, Clinton H. Whitehurst Jr.
Publications
No abstract provided.
The Economic Situation, 1998 October, Bruce Yandle
The Economic Situation, 1998 October, Bruce Yandle
Publications
Quarterly report on the economic situation of the United States and South Carolina.
The Problem Of Hipparcos Distances To Open Clusters. Ii. Constraints From Nearby Field Stars, David R. Soderblom, Jeremy R. King, Robert B. Hanson, Burton F. Jones, Debra Fischer, John R. Stauffer, Marc H. Pisonneault
The Problem Of Hipparcos Distances To Open Clusters. Ii. Constraints From Nearby Field Stars, David R. Soderblom, Jeremy R. King, Robert B. Hanson, Burton F. Jones, Debra Fischer, John R. Stauffer, Marc H. Pisonneault
Publications
This paper examines the discrepancy between distances to nearby open clusters as determined by parallaxes from Hipparcos compared to traditional main-sequence fitting. The biggest difference is seen for the Pleiades, and our hypothesis is that if the Hipparcos distance to the Pleiades is correct, then similar subluminous zero-age main-sequence (ZAMS) stars should exist elsewhere, including in the immediate solar neighborhood. We examine a color-magnitude diagram of very young and nearby solar-type stars and show that none of them lie below the traditional ZAMS, despite the fact that the Hipparcos Pleiades parallax would place its members 0.3 mag below that ZAMS. …
The Problem Of Hipparcos Distances To Open Clusters. I. Constraints From Multicolor Main-Sequence Fitting, Marc H. Pinsonneault, John Stauffer, David Soderblom, Jeremy R. King, Robert B. Hanson
The Problem Of Hipparcos Distances To Open Clusters. I. Constraints From Multicolor Main-Sequence Fitting, Marc H. Pinsonneault, John Stauffer, David Soderblom, Jeremy R. King, Robert B. Hanson
Publications
Parallax data from the Hipparcos mission allow the direct distance to open clusters to be compared with the distance inferred from main-sequence (MS) Ðtting. There are surprising differences between the two distance measurements, indicating either the need for changes in the cluster compositions or reddening, underlying problems with the technique of MS Ðtting, or systematic errors in the Hipparcos parallaxes at the 1 mas level. We examine the di†erent possibilities, focusing on MS fitting in both metallicity-sensitive B[V and metallicity-insensitive V [I for five well-studied systems (the Hyades, Pleiades, a Per, Praesepe, and Coma Ber). The Hipparcos distances to the …
Nuclear Reactions Governing The Nucleosynthesis Of 44ti, L.-S. The, Donald D. Clayton, L Jin, Bradley S. Meyer
Nuclear Reactions Governing The Nucleosynthesis Of 44ti, L.-S. The, Donald D. Clayton, L Jin, Bradley S. Meyer
Publications
Large excesses of 44Ca in certain presolar graphite and silicon carbide grains give strong evidence for 44Ti production in supernovae. Furthermore, recent detection of the 44Ti c line from the Cas A super-nova remnant by the Compton Gamma Ray Observatory Compton Telescope shows that radioactive 44Ti is produced in supernovae. These make the 44Ti abundance an observable diagnostic of supernovae. Through use of a nuclear reaction network, we have systematically varied reaction rates and groups of reaction rates to experimentally identify those that govern 44Ti abundance in core-collapse supernova nucleosynthesis. We survey the nuclear-rate dependence by repeated calculations of the …
Evidence For A Galactic Γ-Ray Halo, Dieter H. Hartmann, D. D. Dixon, E. D. Kolaczyk, J. Samimi, R. Diehl, G. Kanbach, H. Mayer-Hasselwander, A. W. Strong
Evidence For A Galactic Γ-Ray Halo, Dieter H. Hartmann, D. D. Dixon, E. D. Kolaczyk, J. Samimi, R. Diehl, G. Kanbach, H. Mayer-Hasselwander, A. W. Strong
Publications
We present quantitative statistical evidence for a γ-ray emission halo surrounding the Galaxy. Maps of the emission are derived. EGRET data were analyzed in a wavelet-based non-parametric hypothesis testing framework, using a model of expected diffuse (Galactic + isotropic) emission as a null hypothesis. The results show a statistically significant large scale halo surrounding the center of the Milky Way as seen from Earth. The halo flux at high latitudes is somewhat smaller than the isotropic γ-ray flux at the same energy, though of the same order (O(10−7–10−6) ph cm−2 s−1 sr−1 above 1 GeV).
On The Association Of Gamma-Ray Bursts With Supernovae, Dieter H. Hartmann, R. M. Kippen, M. S. Briggs, J. M. Kommers, C. Kouveliotou, K. Hurley, C. R. Robinson, J. Van Paradijs, T. J. Galama, P. M. Vresswijk
On The Association Of Gamma-Ray Bursts With Supernovae, Dieter H. Hartmann, R. M. Kippen, M. S. Briggs, J. M. Kommers, C. Kouveliotou, K. Hurley, C. R. Robinson, J. Van Paradijs, T. J. Galama, P. M. Vresswijk
Publications
The recent discovery of a supernova (SN 1998bw) seemingly associated with GRB 980425 adds a new twist to the decades-old debate over the origin of gamma-ray bursts. To investigate the possibility that some (or all) bursts are associated with supernovae, we performed a systematic search for temporal/angular correlations using catalogs of BATSE and BATSE/Ulysses burst locations. We find no associations with any of the precise BATSE/Ulysses locations, which allows us to conclude that the fraction of high-fluence gamma-ray bursts from known supernovae is small (<0.2%). For the more numerous weaker bursts, the corresponding limiting fraction of 1.5% is less constraining due to the imprecise locations of these events. This limit (1.5% ≃ 18 bursts) allows that a large fraction of the recent supernovae used as a comparison data set (18 supernovae ≃ 20%) could have associated gamma-ray bursts. Thus, although we find no significant evidence to support a burst/supernova association, the possibility cannot be excluded for weak bursts.
The Forgotten Concepts Of Sovereignty, Independence And Nationhood As Criteria For Un Membership, 1998 July, Clinton H. Whitehurst Jr.
The Forgotten Concepts Of Sovereignty, Independence And Nationhood As Criteria For Un Membership, 1998 July, Clinton H. Whitehurst Jr.
Publications
No abstract provided.
African-American Travelers, 1998 July, Author Unknown
African-American Travelers, 1998 July, Author Unknown
Publications
No abstract provided.
Insight: Gambling In South Carolina: A Special Edition, 1998 July, Holley Hewitt Ulbrich
Insight: Gambling In South Carolina: A Special Edition, 1998 July, Holley Hewitt Ulbrich
Publications
No abstract provided.
The Economic Situation, 1998 July, Bruce Yandle
The Economic Situation, 1998 July, Bruce Yandle
Publications
Quarterly report on the economic situation of the United States and South Carolina.
Lithium In The Young Cluster Ngc 2264, Jeremy R. King
Lithium In The Young Cluster Ngc 2264, Jeremy R. King
Publications
We use moderate-resolution, moderate signal-to-noise ratio spectroscopy to derive Li abundances for six F and G stars in the young (few Myr) cluster NGC 2264. These are combined with consistently determined abundances of five NGC 2264 G and K stars having published Li data. The mean non-LTE abundance, calculated with photometric temperatures, is log N(Li) = 3.27 ± 0.05. This is essentially identical to the meteoritic value, providing no evidence of Galactic Li enrichment over the past 4.6 Gyr—at least to the extent that the meteoritic value represents a typical "cosmic" value at that time. The scatter of 0.16 dex …
High Resolution Spectroscopy Of Some Very Active Southern Stars, David R. Soderblom, Jeremy R. King, Todd J. Henry
High Resolution Spectroscopy Of Some Very Active Southern Stars, David R. Soderblom, Jeremy R. King, Todd J. Henry
Publications
We have obtained high-resolution echelle spectra of 18 solar-type stars that an earlier survey showed to have very high levels of Ca II H and K emission. Most of these stars belong to close binary systems, but five remain as probable single stars or well-separated binaries that are younger than the Pleiades on the basis of their lithium abundances and Hα emission. Three of these probable single stars also lie more than 1 mag above the main sequence in a color-magnitude diagram, and appear to have ages of 10 to 15 Myr. Two of them, HD 202917 and HD 222259, …
Criticizing India's Nuclear Weapons Program Bears A High Price, 1998 May 20, Clinton H. Whitehurst Jr.
Criticizing India's Nuclear Weapons Program Bears A High Price, 1998 May 20, Clinton H. Whitehurst Jr.
Publications
No abstract provided.
Theory Of Quasi-Equilibrium Nucelosynthesis And Applications To Matter Expanding From High Temperature And Density, Bradley S. Meyer, Tracy D. Krishnan, Donald D. Clayton
Theory Of Quasi-Equilibrium Nucelosynthesis And Applications To Matter Expanding From High Temperature And Density, Bradley S. Meyer, Tracy D. Krishnan, Donald D. Clayton
Publications
Our first purpose is construction of a formal theory of quasi-equilibrium. We define quasi-equilibrium, in its simplest form, as statistical equilibrium in the face of an extra constraint on the nuclear populations. We show that the extra constraint introduces a uniform translation of the chemical potentials for the heavy nuclei and derive the abundances in terms of it. We then generalize this theory to accommodate any number of constraints. For nucleosynthesis, the most important constraint occurs when the total number of heavy nuclei Yh within a system of nuclei differs from the number that would exist in nuclear statistical equilibrium …
Equivocal Notions Of Accuracy And Genetic Screening Of The General Population, Kelly C. Smith
Equivocal Notions Of Accuracy And Genetic Screening Of The General Population, Kelly C. Smith
Publications
The explosive growth in genetic technology will quickly make possible an unprecedented number of tests for genetically based conditions. A necessary condition for the use of such tests without risk of harm to the patient is that they are “accurate”. However, most discussions of test accuracy in the literature have equivocated between two importantly different meanings of the word. In particular, it must be kept in mind that a high analytical accuracy does not imply a high diagnostic accuracy. Questions about the diagnostic accuracy of genetic tests loom large at present given our limited knowledge of the complex etiology of …
Evaluation Report: Aiken/Edgefield/Saluda Counties Regional Sewer Line Infrastructure Demonstration Project, 1998 May, Bruce Ransom, Mark Colburn
Evaluation Report: Aiken/Edgefield/Saluda Counties Regional Sewer Line Infrastructure Demonstration Project, 1998 May, Bruce Ransom, Mark Colburn
Publications
No abstract provided.
Delivery Of Resource Information To Local Entities In Rural Areas And Small Towns, 1998 May, Bruce Ransom
Delivery Of Resource Information To Local Entities In Rural Areas And Small Towns, 1998 May, Bruce Ransom
Publications
No abstract provided.
Hd 98800: A Unique Stellar System Of Post-T Tauri Stars, David Soderblom, Jeremy R. King, Lionell Siess, Keith S. Noll, Diane M. Gilmore, Todd J. Henry, Edmund Nelan, Christopher J. Burrows, Robert A. Brown, M.A.C. Perryman
Hd 98800: A Unique Stellar System Of Post-T Tauri Stars, David Soderblom, Jeremy R. King, Lionell Siess, Keith S. Noll, Diane M. Gilmore, Todd J. Henry, Edmund Nelan, Christopher J. Burrows, Robert A. Brown, M.A.C. Perryman
Publications
HD 98800 is a system of four stars, and it has a large infrared excess that is thought to be due to a dust disk within the system. In this paper we present new astrometric observations made with Hipparcos, as well as photometry from Hubble Space Telescope WFPC2 images. Combining these observations and reanalyzing previous work allow us to estimate the age and masses of the stars in the system. Uncertainty in these ages and masses results from uncertainty in the temperatures of the stars and any reddening they may have. We find that HD 98800 is most probably about …