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Articles 6601 - 6630 of 8865

Full-Text Articles in Astrophysics and Astronomy

Multi-Channel Digital Receiver Data Acquisition System For The Arecibo Radar System, Ryan Seal Jan 2008

Multi-Channel Digital Receiver Data Acquisition System For The Arecibo Radar System, Ryan Seal

Theses and Dissertations

Digital Receivers are commercially available, cost effective solutions that are becoming commonplace in modern data acquisition systems (MDAS). The digital receiver has the ability to be reconfigured via software, making MDAS flexible for a variety of applications. This thesis describes the design and implementation of a complete MDAS using a general purpose computer (GPC) equipped with a digital receiver card. This system will replace the older DAS (baseband sampling) used by the Space and Atmospheric Science (SAS) group at the Arecibo Observatory (AO). Emphasis is placed on a generic system easily adaptable to a specific application with minimal effort. A …

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Quantitative Constraints On The Transport Properties Of Hot Partonic Matter From Semi-Inclusive Single High Transverse Momentum Pion Suppression In Au+Au Collisions At √Snn = 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Quantitative Constraints On The Transport Properties Of Hot Partonic Matter From Semi-Inclusive Single High Transverse Momentum Pion Suppression In Au+Au Collisions At √Snn = 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

The PHENIX experiment has measured the suppression of semi-inclusive single high-transverse-momentum π0's in Au+Au collisions at √sNN = 200 GeV. The present understanding of this suppression is in terms of energy loss of the parent (fragmenting) parton in a dense color-charge medium. We have performed a quantitative comparison between various parton energy-loss models and our experimental data. The statistical point-to-point uncorrelated as well as correlated systematic uncertainties are taken into account in the comparison. We detail this methodology and the resulting constraint on the model parameters, such as the initial color-charge density dNg/dy, the medium transport coefficient q, or the …

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High-Energy Electron Beams Launched Into Space By Thunderstorms, Joseph R. Dwyer, Brian W. Grefenstette, David M. Smith Jan 2008

High-Energy Electron Beams Launched Into Space By Thunderstorms, Joseph R. Dwyer, Brian W. Grefenstette, David M. Smith

Aerospace, Physics, and Space Science Faculty Publications

Using CGRO/BATSE data, a possible new source of high-energy electrons and positrons in the earth's inner magnetosphere is presented. These particles are generated within the upper atmosphere by Compton scattering and pair-production of gamma-rays originating from near the tropopause as Terrestrial Gamma-ray Flashes (TGFs). Once created, these energetic electrons and positrons follow the geomagnetic field into the inner magnetosphere where they can be detected in low-earth orbit, either near the TGF magnetic foot point or at the conjugate point several thousand kilometers away. Approximately 17% of CGRO/BATSE events previously identified as terrestrial gamma-ray flashes are, in fact, such electrons and …

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The Warps Survey. Vii. The Warps-Ii Cluster Catalog, Donald J. Horner, Eric S. Perlman, Harald Ebeling, Laurence R. Jones, Caleb A. Scharf, Gary Wegner, Matthew Malkan, Ben Maughan Jan 2008

The Warps Survey. Vii. The Warps-Ii Cluster Catalog, Donald J. Horner, Eric S. Perlman, Harald Ebeling, Laurence R. Jones, Caleb A. Scharf, Gary Wegner, Matthew Malkan, Ben Maughan

Aerospace, Physics, and Space Science Faculty Publications

We present the galaxy cluster catalog from the second, larger phase of the Wide Angle ROSAT Pointed Survey (WARPS), an X-ray selected survey for high-redshift galaxy clusters. WARPS is among the largest deep X-ray cluster surveys and is being used to study the properties and evolution of galaxy clusters. The WARPS-II sample contains 125 clusters serendipitously detected in a survey of 301 ROSAT PSPC pointed observations and covers a sky area of 56.7 deg2. Of these 125 clusters, 53 have not been previously reported in the literature. We have nearly complete spectroscopic follow-up of the clusters, which range in redshift …

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The Extreme Outburst Of Ex Lup In 2008: Optical Spectra And Light Curve, Ágnes Kóspál, P. Németh, Péter Ábrahám, Mária Kun, Arne A. Henden, Albert F. Jones Jan 2008

The Extreme Outburst Of Ex Lup In 2008: Optical Spectra And Light Curve, Ágnes Kóspál, P. Németh, Péter Ábrahám, Mária Kun, Arne A. Henden, Albert F. Jones

Aerospace, Physics, and Space Science Faculty Publications

EX Lup is the prototype of EXors, a class of pre-main sequence eruptive variables, exhibiting unpredictable brightenings lasting some months (Herbig, 1977; Herbig et al., 2001; Herbig, 2007). According to the current picture, eruptions of pre-main sequence stars are caused by enhanced accretion (Hartmann & Kenyon, 1996). In quiescent phase, EX Lup has typically V 13 mag, while in outburst, it may brighten by 1{4 mag. The last known are-up happened in 2002 (Herbig, 2007). As was announced by Jones (2008), EX Lup has been in outburst again since at least 2008 January 15. Based on visual estimates, the star …

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The Pulsation Modes Of The Pre-White Dwarf Pg 1159-035, Jörge E.S. Costa, Matt A. Wood, Thomas J. Ahrens Jan 2008

The Pulsation Modes Of The Pre-White Dwarf Pg 1159-035, Jörge E.S. Costa, Matt A. Wood, Thomas J. Ahrens

Aerospace, Physics, and Space Science Faculty Publications

Context. PG 1159-035 , a pre-white dwarf with Teff ≃ 140 000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to measure the stellar mass, the rotational period and the inclination of the rotation axis, to estimate an upper limit for the magnetic field, and even to obtain information about the inner stratification of the star. …

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Study Of The Solar Anisotropy Of Cosmic Ray Primaries Of About 200 Gev Energy With The L3+C Muon Detector, G Baksay, L Baksay, K Dehmelt, M Hohlmann, Z Szillasi, I Vodopianov, The L3 Collaboration Jan 2008

Study Of The Solar Anisotropy Of Cosmic Ray Primaries Of About 200 Gev Energy With The L3+C Muon Detector, G Baksay, L Baksay, K Dehmelt, M Hohlmann, Z Szillasi, I Vodopianov, The L3 Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Context. Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims. A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods. The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the angular distribution of atmospheric muons with energies above 20 GeV. This distribution is used to investigate the isotropy of the time-dependent intensity of the primary cosmic-ray flux with a Fourier analysis. Results. A small deviation from isotropy at energies around …

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Charged Hadron Multiplicity Fluctuations In Au+Au And Cu+Cu Collisions From √Snn=22.5 To 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Charged Hadron Multiplicity Fluctuations In Au+Au And Cu+Cu Collisions From √Snn=22.5 To 200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

A comprehensive survey of event-by-event fluctuations of charged hadron multiplicity in relativistic heavy ions is presented. The survey covers Au+Au collisions at √sNN=62.4 and 200 GeV, and Cu+Cu collisions at √sNN=22.5,62.4, and 200 GeV. Fluctuations are measured as a function of collision centrality, transverse momentum range, and charge sign. After correcting for nondynamical fluctuations due to fluctuations in the collision geometry within a centrality bin, the remaining dynamical fluctuations expressed as the variance normalized by the mean tend to decrease with increasing centrality. The dynamical fluctuations are consistent with or below the expectation from a superposition of participant nucleon-nucleon collisions …

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Dihadron Azimuthal Correlations In Au+Au Collisions At √Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Dihadron Azimuthal Correlations In Au+Au Collisions At √Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Azimuthal angle (Δϕ) correlations are presented for a broad range of transverse momentum (0.4

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Transverse Momentum And Centrality Dependence Of Dihadron Correlations In Au+Au Collisions At Snn=200 Gev: Jet Quenching And The Response Of Partonic Matter, Andrew Marshall Adare, Gyöngyi Baksay, László Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Transverse Momentum And Centrality Dependence Of Dihadron Correlations In Au+Au Collisions At Snn=200 Gev: Jet Quenching And The Response Of Partonic Matter, Andrew Marshall Adare, Gyöngyi Baksay, László Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

Azimuthal angle (Δ) correlations are presented for charged hadrons from dijets for 0.4

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Hubble Space Telescope Near-Infrared Snapshot Survey Of 3cr Radio Source Counterparts. Ii. An Atlas And Inventory Of The Host Galaxies, Mergers, And Companions, David J. E. Floyd, Eric Perlman Jan 2008

Hubble Space Telescope Near-Infrared Snapshot Survey Of 3cr Radio Source Counterparts. Ii. An Atlas And Inventory Of The Host Galaxies, Mergers, And Companions, David J. E. Floyd, Eric Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present the second part of an H-band (1.6 μm) "atlas" of z < 0.3 3CR radio galaxies, using the Hubble Space Telescope Near Infrared Camera and Multi-Object Spectrometer (HST NICMOS2). We present new imaging for 21 recently acquired sources and host galaxy modeling for the full sample of 101 (including 11 archival) - an 87% completion rate. Two different modeling techniques are applied, following those adopted by the galaxy morphology and the quasar host galaxy communities. Results are compared and found to be in excellent agreement, although the former breaks down in the case of sources with strong active galactic nuclei (AGNs). Companion sources are tabulated, and the presence of mergers, tidal features, dust disks, and jets are cataloged. The tables form a catalog for those interested in the structural and morphological dust-free host galaxy properties of the 3CR sample, and for comparison with morphological studies of quiescent galaxies and quasar host galaxies. Host galaxy masses are estimated and found to typically lie at around 2 × 1011 M⊙. In general, the population is found to be consistent with the local population of quiescent elliptical galaxies, but with a longer tail to low Sérsic index, mainly consisting of low-redshift (z < 0.1) and low-radio-power (FR I) sources. A few unusually disky FR II host galaxies are picked out for further discussion. Nearby external sources are identified in the majority of our images, many of which we argue are likely to be companion galaxies or merger remnants. The reduced NICMOS data are now publicly available from our Web site.

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The Warps Survey. Vii. The Warps‐Ii Cluster Catalog, Donald J. Horner, Eric S. Perlman, Harald Ebeling, Laurence Jones, Caleb A. Scharf, Gary Wegner, Matthew Malkan, Ben Maughan Jan 2008

The Warps Survey. Vii. The Warps‐Ii Cluster Catalog, Donald J. Horner, Eric S. Perlman, Harald Ebeling, Laurence Jones, Caleb A. Scharf, Gary Wegner, Matthew Malkan, Ben Maughan

Dartmouth Scholarship

We present the galaxy cluster catalog from the second, larger phase of the Wide Angle ROSAT Pointed Survey (WARPS), an X-ray selected survey for high-redshift galaxy clusters. WARPS is among the largest deep X-ray cluster surveys and is being used to study the properties and evolution of galaxy clusters. The WARPS-II sample contains 125 clusters serendipitously detected in a survey of 301 ROSAT PSPC pointed observations and covers a sky area of 56.7 deg2. Of these 125 clusters, 53 have not been previously reported in the literature. We have nearly complete spectroscopic follow-up of the clusters, which range …

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Beating The Spin-Down Limit On Gravitational Wave Emission From The Crab Pulsar, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, I. A. Bilenko, Tiffany Z. Summerscales Jan 2008

Beating The Spin-Down Limit On Gravitational Wave Emission From The Crab Pulsar, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, I. A. Bilenko, Tiffany Z. Summerscales

Faculty Publications

We present direct upper limits on gravitational wave emission from the Crab pulsar using data from the first 9 months of the fifth science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). These limits are based on two searches. In the first we assume that the gravitational wave emission follows the observed radio timing, giving an upper limit on gravitational wave emission that beats indirect limits inferred from the spin-down and braking index of the pulsar and the energetics of the nebula. In the second we allow for a small mismatch between the gravitational and radio signal frequencies and interpret …

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Determining The Refractive Index In The Extreme Ultraviolet Using Kramers-Kronig On Thin-Film Scandium Oxide Transmission Data, David D. Allred, Jacqualine J. Butterfield Jan 2008

Determining The Refractive Index In The Extreme Ultraviolet Using Kramers-Kronig On Thin-Film Scandium Oxide Transmission Data, David D. Allred, Jacqualine J. Butterfield

Faculty Publications

Whereas the real part of the refractive index is dependent on both transmittance and reflectance, the imaginary part can be determined from transmittance data alone. It is possible to use Kramers-Kronig analysis to calculate the real part if the imaginary part is known over a sufficiently broad range. We show that the delta calculated from reflection and transmission data without taking into account roughness may underestimate the real part of the refractive index of the scandium oxide samples we are studying by up to 40% near 270 eV.

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Next-To-Leading Order Evolution Of Color Dipoles, Ian Balitsky, Giovanni A. Chirilli Jan 2008

Next-To-Leading Order Evolution Of Color Dipoles, Ian Balitsky, Giovanni A. Chirilli

Physics Faculty Publications

The small-x deep inelastic scattering in the saturation region is governed by the nonlinear evolution of Wilson-line operators. In the leading logarithmic approximation it is given by the Balitsky-Kovchegov equation for the evolution of color dipoles. In the next-to-leading order the Balitsky-Kovchegov equation gets contributions from quark and gluon loops as well as from the tree gluon diagrams with quadratic and cubic nonlinearities. We calculate the gluon contribution to the small-x evolution of Wilson lines (the quark part was obtained earlier).

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Dielectronic Recombination And Stability Of Warm Gas In Active Galactic Nuclei, Susmita Chakravorty, Ajit K. Kembhavi, Martin Elvis, Gary J. Ferland, N. R. Badnell Jan 2008

Dielectronic Recombination And Stability Of Warm Gas In Active Galactic Nuclei, Susmita Chakravorty, Ajit K. Kembhavi, Martin Elvis, Gary J. Ferland, N. R. Badnell

Physics and Astronomy Faculty Publications

Understanding the thermal equilibrium (stability) curve may offer insights into the nature of the warm absorbers often found in active galactic nuclei. Its shape is determined by factors such as the spectrum of the ionizing continuum and the chemical composition of the gas. We find that the stability curves obtained under the same set of the above-mentioned physical factors, but using recently derived dielectronic recombination rates, give significantly different results, especially in the regions corresponding to warm absorbers, leading to different physical predictions. Using the current rates we find a larger probability of having a thermally stable warm absorber at …

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First Results From Ideal 2-D Mhd Reconstruction: Magnetopause Reconnection Event Seen By Cluster, W. L. Teh, B. U. O. Sonnerup Jan 2008

First Results From Ideal 2-D Mhd Reconstruction: Magnetopause Reconnection Event Seen By Cluster, W. L. Teh, B. U. O. Sonnerup

Dartmouth Scholarship

We have applied a new reconstruction method (Sonnerup and Teh, 2008), based on the ideal single-fluid MHD equations in a steady-state, two-dimensional geometry, to a reconnection event observed by the Cluster-3 (C3) space- craft on 5 July 2001, 06:23 UT, at the dawn-side Northern- Hemisphere magnetopause. The event has been previously studied by use of Grad-Shafranov (GS) reconstruction, per- formed in the deHoffmann-Teller frame, and using the as- sumption that the flow effects were either negligible or the flow was aligned with the magnetic field. Our new method allows the reconstruction to be performed in the frame of reference moving …

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The Crab Nebula's Dynamical Age As Measured From Its Northern Filamentary Jet, G. C. Rudie, R. A. Fesen, T. Yamada Jan 2008

The Crab Nebula's Dynamical Age As Measured From Its Northern Filamentary Jet, G. C. Rudie, R. A. Fesen, T. Yamada

Dartmouth Scholarship

We present a deep [O III] 4959,5007 image of the northern filamentary jet in the Crab Nebula taken with the 8.2m Subaru telescope. Using this image and an image taken with the KPNO 4m in 1988 (Fesen & Staker 1993), we have computed proper motions for 35 locations in the jet. The results suggest that when compared to the main body of the remnant, the jet experienced less outward acceleration from the central pulsar's rapidly expanding synchrotron nebula. The jet's apparent expansion rate yields an undecelerated explosion date for the Crab Nebula of 1055 plus or minus 24 C.E., a …

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Kinetics And Thermodynamics Of Salt-Dependent T7 Gene 2.5 Protein Binding To Single- And Double-Stranded Dna., Leila Shokri, Boriana Marintcheva, Mootaz Eldib, Andreas Hanke, Ioulia Rouzina, Mark C. Williams Jan 2008

Kinetics And Thermodynamics Of Salt-Dependent T7 Gene 2.5 Protein Binding To Single- And Double-Stranded Dna., Leila Shokri, Boriana Marintcheva, Mootaz Eldib, Andreas Hanke, Ioulia Rouzina, Mark C. Williams

Physics & Astronomy Faculty Publications

Bacteriophage T7 gene 2.5 protein (gp2.5) is a single-stranded DNA (ssDNA)-binding protein that has essential roles in DNA replication, recombination and repair. However, it differs from other ssDNA-binding proteins by its weaker binding to ssDNA and lack of cooperative ssDNA binding. By studying the rate-dependent DNA melting force in the presence of gp2.5 and its deletion mutant lacking 26 C-terminal residues, we probe the kinetics and thermodynamics of gp2.5 binding to ssDNA and double-stranded DNA (dsDNA). These force measurements allow us to determine the binding rate of both proteins to ssDNA, as well as their equilibrium association constants to dsDNA. …

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Editorial, First Science And Policy Issue, Jscas Jan 2008

Editorial, First Science And Policy Issue, Jscas

Journal of the South Carolina Academy of Science

No abstract provided.

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With The Help Of South Carolina Research Universities, Scra Demonstrates Leadership In Applied Research And Commercialization Within Sc, Bill Mahoney Jan 2008

With The Help Of South Carolina Research Universities, Scra Demonstrates Leadership In Applied Research And Commercialization Within Sc, Bill Mahoney

Journal of the South Carolina Academy of Science

No abstract provided.

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Sc Inbre: A Catalyst For Biomedical Research Development In South Carolina, Lucia A. Pirisi-Creek M.D, Scott Little, Ph.D. Jan 2008

Sc Inbre: A Catalyst For Biomedical Research Development In South Carolina, Lucia A. Pirisi-Creek M.D, Scott Little, Ph.D.

Journal of the South Carolina Academy of Science

No abstract provided.

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Cold Nuclear Matter Effects On J/Ψ Production As Constrained By Deuteron-Gold Measurements At Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration Jan 2008

Cold Nuclear Matter Effects On J/Ψ Production As Constrained By Deuteron-Gold Measurements At Snn=200 Gev, Andrew Marshall Adare, Gyöngyi Baksay, László A. Baksay, Klaus Dehmelt, Marcus Hohlmann, S. Rembeczki, Phenix Collaboration

Aerospace, Physics, and Space Science Faculty Publications

We present a new analysis of J/ψ production yields in deuteron-gold collisions at √sNN=200 GeV using data taken from the PHENIX experiment in 2003 and previously published in S. S. Adler et al. [Phys. Rev. Lett 96, 012304 (2006)]. The high statistics proton-proton J/ψ data taken in 2005 are used to improve the baseline measurement and thus construct updated cold nuclear matter modification factors (RdAu). A suppression of J/ψ in cold nuclear matter is observed as one goes forward in rapidity (in the deuteron-going direction), corresponding to a region more sensitive to initial-state low-ₓ gluons in the gold nucleus. The …

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Constraining Convection Parameters From The Light Curve Shapes Of Pulsating White Dwarf Stars: The Cases Of Ec 14012-1446 And Wd 1524-0030, Gerald Handler, Judith L. Provençal, Michael H. Montgomery, Encarni Romero-Colmenero, Kaushar Sanchawala, Monika A. Lendl, Matt A. Wood, Isaac M. Silver, Paul G. Beck, Wenping Chen Jan 2008

Constraining Convection Parameters From The Light Curve Shapes Of Pulsating White Dwarf Stars: The Cases Of Ec 14012-1446 And Wd 1524-0030, Gerald Handler, Judith L. Provençal, Michael H. Montgomery, Encarni Romero-Colmenero, Kaushar Sanchawala, Monika A. Lendl, Matt A. Wood, Isaac M. Silver, Paul G. Beck, Wenping Chen

Aerospace, Physics, and Space Science Faculty Publications

Montgomery [1] developed a method to probe convection in pulsating white dwarf stars which allows the recovery of the thermal response time of the convection zone by fitting observed non sinusoidal light curves. He applied this method to two objects; the Whole Earth Telescope (WET) observed the pulsating DB white dwarf GD 358 for just this purpose. Given this WET run's success, it is time to extend Montgomery's method to pulsating DA white dwarf (ZZ Ceti) stars. We present observations of two ZZ Ceti stars, WD 1524 - 0030 and EC 14012 - 1446, both observed from multiple sites. EC …

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Phase-Dependent X-Ray Observations Of The Beta Lyrae System: No Eclipse In The Soft Band., Richard Ignace, L. Oskinova, W. Waldron, J. Hoffman, W.-R. Hamann Jan 2008

Phase-Dependent X-Ray Observations Of The Beta Lyrae System: No Eclipse In The Soft Band., Richard Ignace, L. Oskinova, W. Waldron, J. Hoffman, W.-R. Hamann

ETSU Faculty Works

Aims.We report on observations of the eclipsing and interacting binary beta Lyrae from the Suzaku X-ray telescope. This system involves an early B star embedded in an optically and geometrically thick disk that is siphoning atmospheric gases from a less massive late B II companion. Methods.Motivated by an unpublished X-ray spectrum from the Einstein X-ray telescope suggesting unusually hard emission, we obtained time with Suzaku for pointings at three different phases within a single orbit. Results.From the XIS detectors, the softer X-ray emission appears typical of an early-type star. What is surprising is the remarkably unchanging character …

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A Photometric Redshift Of Z = 1.8+0.4 -.3 For The Agile Grb 080514b, A. Rossi, A. De Ugarte Postigo, P. Ferrero, D. A. Kann, S. Klose, S. Schulze, J. Greiner, P. Schady, R. Filgas, E. E. Gonsalves, A. Küpcü Yolda¸S, T. Krühler, G. Szokoly, A. Yolda¸S, P. M.J. Afonso, C. Clemens, J. S. Bloom, D. A. Perley, J. P.U. Fynbo, A. J. Castro-Tirado, J. Gorosabel, P. Kubánek, Adria Updike, D. H. Hartmann, A. Giuliani, S. T. Holland, L. Hanlon, M. Bremer, J. French, G. Melady, D. A. García-Hernández Jan 2008

A Photometric Redshift Of Z = 1.8+0.4 -.3 For The Agile Grb 080514b, A. Rossi, A. De Ugarte Postigo, P. Ferrero, D. A. Kann, S. Klose, S. Schulze, J. Greiner, P. Schady, R. Filgas, E. E. Gonsalves, A. Küpcü Yolda¸S, T. Krühler, G. Szokoly, A. Yolda¸S, P. M.J. Afonso, C. Clemens, J. S. Bloom, D. A. Perley, J. P.U. Fynbo, A. J. Castro-Tirado, J. Gorosabel, P. Kubánek, Adria Updike, D. H. Hartmann, A. Giuliani, S. T. Holland, L. Hanlon, M. Bremer, J. French, G. Melady, D. A. García-Hernández

Arts & Sciences Faculty Publications

The AGILE gamma-ray burst GRB 080514B is the first detected to have emission above 30 MeV and an optical afterglow. However, no spectroscopic redshift for this burst is known.We report on our ground-based optical/NIR and millimeter follow-up observations of this event at several observatories, including the multi-channel imager GROND on La Silla, supplemented by Swift UVOT and Swift XRT data. The spectral energy distribution (SED) of the optical/NIR afterglow is found to decline sharply bluewards to the UV bands, which can be utilized in estimating the redshift. Fitting the SED from the Swift UVOT uvw2 band to the H band, …

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The Rapidly Flaring Afterglow Of The Very Bright And Energetic Grb 070125, Adria Updike, Josh B. Haislip, Melissa C. Nysewander, Andrew S. Fruchter, D. Alexander Kann, Sylvio Klose, Peter A. Milne, G. Grant Williams, Weikang Zheng, Carl W. Hergenrother, Jason X. Prochaska, Jules P. Halpern, Nestor Mirabal, John R. Thorstensen, Alexander J. Van Der Horst, Rhaana L.C. Starling, Judith L. Racusin, David N. Burrows, N. P.M. Kuin, Peter W.A. Roming, Eric Bellm, Kevin Hurley, Weidong Li, Alexei V. Filippenko, Cullen Blake, Dan Starr, Emilio E. Falco, Warren R. Brown, Xinyu Dai, Jinsong Deng, Liping Xin, Yulei Qiu, Jianyan Wei, Yuji Urata, Domenico Nanni, Elisabetta Maiorano, Eliana Palazzi, Guiseppe Greco, Corrado Bartolini, Adriano Guarnieri, Adalberto Piccioni, Graziella Pizzichini, Federica Terra, Kuntal Misra, B. C. Bhatt, G. C. Anupama, X. Fan, L. Jiang, Ralph A.M.J. Wijers, Daniel E. Reichart, Hala A. Eid, Ginger Bryngelson, Jason Puls, R. C. Goldthwaite, Dieter H. Hartmann Jan 2008

The Rapidly Flaring Afterglow Of The Very Bright And Energetic Grb 070125, Adria Updike, Josh B. Haislip, Melissa C. Nysewander, Andrew S. Fruchter, D. Alexander Kann, Sylvio Klose, Peter A. Milne, G. Grant Williams, Weikang Zheng, Carl W. Hergenrother, Jason X. Prochaska, Jules P. Halpern, Nestor Mirabal, John R. Thorstensen, Alexander J. Van Der Horst, Rhaana L.C. Starling, Judith L. Racusin, David N. Burrows, N. P.M. Kuin, Peter W.A. Roming, Eric Bellm, Kevin Hurley, Weidong Li, Alexei V. Filippenko, Cullen Blake, Dan Starr, Emilio E. Falco, Warren R. Brown, Xinyu Dai, Jinsong Deng, Liping Xin, Yulei Qiu, Jianyan Wei, Yuji Urata, Domenico Nanni, Elisabetta Maiorano, Eliana Palazzi, Guiseppe Greco, Corrado Bartolini, Adriano Guarnieri, Adalberto Piccioni, Graziella Pizzichini, Federica Terra, Kuntal Misra, B. C. Bhatt, G. C. Anupama, X. Fan, L. Jiang, Ralph A.M.J. Wijers, Daniel E. Reichart, Hala A. Eid, Ginger Bryngelson, Jason Puls, R. C. Goldthwaite, Dieter H. Hartmann

Arts & Sciences Faculty Publications

No abstract provided.

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Multiwavelength Analysis Of The Intriguing Grb 061126: The Reverse Shock Scenario And Magnetization, A. Gomboc, S. Kobayashi, C. Guidorzi, A. Melandri, V. Mangano, B. Sbarufatti, C. G. Mundell, P. Schady, R. J. Smith, Adria Updike, D. A. Kann, K. Misra, E. Rol, A. Pozanenko, A. J. Castro-Tirado, G. C. Anupama, D. Bersier, M. F. Bode, D. Carter, P. Curran, A. Fruchter, J. Graham, D. H. Hartmann, M. Ibrahimov, A. Levan, A. Monfardini, C. J. Mottram, P. T. O’Brien, P. Prema, D. K. Sahu, I. A. Steele, N. R. Tanvir, K. Wiersema Jan 2008

Multiwavelength Analysis Of The Intriguing Grb 061126: The Reverse Shock Scenario And Magnetization, A. Gomboc, S. Kobayashi, C. Guidorzi, A. Melandri, V. Mangano, B. Sbarufatti, C. G. Mundell, P. Schady, R. J. Smith, Adria Updike, D. A. Kann, K. Misra, E. Rol, A. Pozanenko, A. J. Castro-Tirado, G. C. Anupama, D. Bersier, M. F. Bode, D. Carter, P. Curran, A. Fruchter, J. Graham, D. H. Hartmann, M. Ibrahimov, A. Levan, A. Monfardini, C. J. Mottram, P. T. O’Brien, P. Prema, D. K. Sahu, I. A. Steele, N. R. Tanvir, K. Wiersema

Arts & Sciences Faculty Publications

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On Well-Balanced Schemes For Non-Equilibrium Flow With Stiff Source Terms, W. Wang, C.-W. Shu, Helen Yee Jan 2008

On Well-Balanced Schemes For Non-Equilibrium Flow With Stiff Source Terms, W. Wang, C.-W. Shu, Helen Yee

United States National Aeronautics and Space Administration: Publications

In the modeling of unsteady reactive problems, the interaction of turbulence with finiterate chemistry introduces a wide range of space and time scales, leading to additional numerical difficulties. A main difficulty stems from the fact that most numerical algorithms used in reacting flows were originally designed to solve non-reacting fluids. As a result, spatial stiffness due to reacting source terms and turbulence/chemistry interaction are major stumbling blocks to numerical algorithm development. One of the important numerical issues is the proper numerical treatment of a system of highly coupled stiff non-linear source terms, which will result in possible spurious steady state …

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First Joint Search For Gravitational-Wave Bursts In Ligo And Geo 600 Data, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, I. Bartos, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, Tiffany Z. Summerscales Jan 2008

First Joint Search For Gravitational-Wave Bursts In Ligo And Geo 600 Data, B. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. A. Arain, M. Araya, H. Armandula, P. Armor, Y. Aso, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, I. Bartos, M. Bastarrika, K. Bayer, J. Betzwieser, P. T. Beyersdorf, Tiffany Z. Summerscales

Faculty Publications

We present the results of the first joint search for gravitational-wave bursts by the LIGO and GEO 600 detectors. We search for bursts with characteristic central frequencies in the band 768-2048 Hz in the data acquired between 22 February and 23 March, 2005 (fourth LSC Science Run-S4). We discuss the inclusion of the GEO 600 data in the Waveburst-CorrPower pipeline that first searches for coincident excess power events without taking into account differences in the antenna responses or strain sensitivities of the various detectors. We compare the performance of this pipeline to that of the coherent Waveburst pipeline based on …

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