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Revised Age For Cm Draconis And Wd 1633+ 572-Toward A Resolution Of Model-Observation Radius Discrepancies, Gregory A. Feiden, Brian Chaboyer 2014 Uppsala University

Revised Age For Cm Draconis And Wd 1633+ 572-Toward A Resolution Of Model-Observation Radius Discrepancies, Gregory A. Feiden, Brian Chaboyer

Dartmouth Scholarship

We report an age revision for the low-mass detached eclipsing binary CM Draconis and its common proper motion companion, WD 1633+572. An age of 8.5 +/- 3.5 Gyr is found by combining an age estimate for the lifetime of WD 1633+572 and an estimate from galactic space motions. The revised age is greater than a factor of two older than previous estimates. Our results provide consistency between the white dwarf age and the system's galactic kinematics, which reveal the system is a highly probable mem


Absolute Properties Of The Eclipsing Binary Star V501 Herculis, Claud H. Sandberg Lacy, Francis C. Fekel 2014 University of Arkansas, Fayetteville

Absolute Properties Of The Eclipsing Binary Star V501 Herculis, Claud H. Sandberg Lacy, Francis C. Fekel

Information Systems and Engineering Management Research Publications

V501 Her is a well detached G3 eclipsing binary star with a period of 8.597687 days for which we have determined very accurate light and radial-velocity curves using robotic telescopes. Results of these data indicate that the component stars have masses of 1.269 ± 0.004 and 1.211 ± 0.003 solar masses, radii of 2.001 ± 0.003 and 1.511 ± 0.003 solar radii, and temperatures of 5683 ± 100 K and 5720 ± 100 K, respectively. Comparison with the Yonsei–Yale series of evolutionary models results in good agreement at an age of about 5.1 Gyr for a somewhat metal-rich composition. Those …


Characterizing The Ab Doradus Moving Group Via High-Resolution Spectroscopy And Kinematic Traceback, Kyle McCarthy, Ronald J. Wilhelm 2014 University of Kentucky

Characterizing The Ab Doradus Moving Group Via High-Resolution Spectroscopy And Kinematic Traceback, Kyle Mccarthy, Ronald J. Wilhelm

Physics and Astronomy Faculty Publications

We present a detailed analysis of 10 proposed F and G members of the nearby, young moving group AB Doradus (ABD). Our sample was obtained using the 2.7 m telescope at the McDonald Observatory with the coude echelle spectrograph, achieving R ~ 60,000 and signal-to-noise ratio ~200. We derive spectroscopic T eff, log(g), [Fe/H], and microturbulance (vt ) using a bootstrap method of the TGVIT software resulting in typical errors of 33K in T eff, 0.08 dex in log(g), 0.03 dex in [Fe/H], and 0.13 km s–1 in vt . …


First All-Sky Search For Continuous Gravitational Waves From Unknown Sources In Binary Systems, Tiffany Summerscales, LIGO Scientific Collaboration and Virgo Collaboration 2014 Andrews University

First All-Sky Search For Continuous Gravitational Waves From Unknown Sources In Binary Systems, Tiffany Summerscales, Ligo Scientific Collaboration And Virgo Collaboration

Faculty Publications

We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to ∼2,254  h and a frequency- and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of …


A Precise Water Abundance Measurement For The Hot Jupiter Wasp-43b, Laura Kreidberg, Jacob L. Bean, Jean-Michel Désert, Michael R. Line, Jonathan J. Fortney, Nikku Madhusudhan, Kevin B. Stevenson, Adam P. Showman, David Charbonneau, Peter McCullough, Sara Seager, Adam Burrows, Gregory W. Henry, Michael H. Williamson, Tiffany Kataria, Derek Homeier 2014 University of Chicago

A Precise Water Abundance Measurement For The Hot Jupiter Wasp-43b, Laura Kreidberg, Jacob L. Bean, Jean-Michel Désert, Michael R. Line, Jonathan J. Fortney, Nikku Madhusudhan, Kevin B. Stevenson, Adam P. Showman, David Charbonneau, Peter Mccullough, Sara Seager, Adam Burrows, Gregory W. Henry, Michael H. Williamson, Tiffany Kataria, Derek Homeier

Information Systems and Engineering Management Research Publications

The water abundance in a planetary atmosphere provides a key constraint on the planet's primordial origins because water ice is expected to play an important role in the core accretion model of planet formation. However, the water content of the solar system giant planets is not well known because water is sequestered in clouds deep in their atmospheres. By contrast, short-period exoplanets have such high temperatures that their atmospheres have water in the gas phase, making it possible to measure the water abundance for these objects. We present a precise determination of the water abundance in the atmosphere of the …


No More Active Galactic Nuclei In Clumpy Disks Than In Smooth Galaxies At Z ~ 2 In Candels/3d-Hst*, Jonathan R. Trump, Guillermo Barro, Stéphanie Juneau, Benjamin J. Weiner, Bin Luo, Gabriel B. Brammer, Eric F. Bell, W. N. Brandt, Avishai Dekel, Yicheng Guo, Philip F. Hopkins, David C. Koo, Dale D. Kocevski, Daniel H. McIntosh, Ivelina Momcheva, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Jeyhan Kartaltepe, Anton M. Koekemoer, Jennifer Lotz, Michael Maseda, Mark Mozena, Kirpal Nandra, David J. Rosario, Gergory R. Zeimann 2014 Pennsylvania State University

No More Active Galactic Nuclei In Clumpy Disks Than In Smooth Galaxies At Z ~ 2 In Candels/3d-Hst*, Jonathan R. Trump, Guillermo Barro, Stéphanie Juneau, Benjamin J. Weiner, Bin Luo, Gabriel B. Brammer, Eric F. Bell, W. N. Brandt, Avishai Dekel, Yicheng Guo, Philip F. Hopkins, David C. Koo, Dale D. Kocevski, Daniel H. Mcintosh, Ivelina Momcheva, S. M. Faber, Henry C. Ferguson, Norman A. Grogin, Jeyhan Kartaltepe, Anton M. Koekemoer, Jennifer Lotz, Michael Maseda, Mark Mozena, Kirpal Nandra, David J. Rosario, Gergory R. Zeimann

Physics and Astronomy Faculty Publications

We use CANDELS imaging, 3D-HST spectroscopy, and Chandra X-ray data to investigate if active galactic nuclei (AGNs) are preferentially fueled by violent disk instabilities funneling gas into galaxy centers at 1.3 < z < 2.4. We select galaxies undergoing gravitational instabilities using the number of clumps and degree of patchiness as proxies. The CANDELS visual classification system is used to identify 44 clumpy disk galaxies, along with mass-matched comparison samples of smooth and intermediate morphology galaxies. We note that despite being mass-matched and having similar star formation rates, the smoother galaxies tend to be smaller disks with more prominent bulges compared to the clumpy galaxies. The lack of smooth extended disks is probably a general feature of the z ~ 2 galaxy population, and means we cannot directly compare with the clumpy and smooth extended disks observed at lower redshift. We find that z ~ 2 clumpy galaxies have slightly enhanced AGN fractions selected by integrated line ratios (in the mass-excitation method), but the spatially resolved line ratios indicate this is likely due to extended phenomena rather than nuclear AGNs. Meanwhile, the X-ray data show that …


2014 Scas Annual Meeting Program, 2014 University of South Carolina

2014 Scas Annual Meeting Program

Journal of the South Carolina Academy of Science

No abstract provided.


Scas Officers And Council Members 2014-2015, 2014 University of South Carolina

Scas Officers And Council Members 2014-2015

Journal of the South Carolina Academy of Science

No abstract provided.


Table Of Contents, 2014 University of South Carolina

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Alleviating Polarity-Conflict At The Heterointerfaces Of Ktao3/Gdsco3 Polar Complex-Oxides, Justin K. Thompson, J. Hwang, John Nichols, John G. Connell, S. Stemmer, Sung S. Ambrose Seo 2014 University of Kentucky

Alleviating Polarity-Conflict At The Heterointerfaces Of Ktao3/Gdsco3 Polar Complex-Oxides, Justin K. Thompson, J. Hwang, John Nichols, John G. Connell, S. Stemmer, Sung S. Ambrose Seo

Physics and Astronomy Faculty Publications

We have synthesized and investigated the heterointerfaces of KTaO3 (KTO) and GdScO3 (GSO), which are both polar complex-oxides along the pseudo-cubic [001] direction. Since their layers have the same, conflicting net charges at interfaces, i.e., KO(−1)/ScO2(−1) or TaO2(+1)/GdO(+1), forming the heterointerface of KTO/GSO should be forbidden due to strong Coulomb repulsion, the so-called polarity conflict. However, we have discovered that atomic reconstruction occurs at the heterointerfaces between KTO thin-films and GSO substrates, which effectively alleviates the polarity conflict without destroying the hetero-epitaxy. Our result demonstrates one of the important ways to create artificial heterostructures …


Tunable Magnetic Properties Of Transition Metal Doped Mos2, Antonis N. Andiotis, Madhu Menon 2014 FORTH, Greece

Tunable Magnetic Properties Of Transition Metal Doped Mos2, Antonis N. Andiotis, Madhu Menon

Physics and Astronomy Faculty Publications

We report a detailed investigation of the electronic and magnetic properties of the transition metal (TM) doped two-dimensional (2D) MoS2 using ab initio calculations. The doping is achieved by substituting two or more Mo atoms by TM atoms of the 3d series. Additionally, the effect of codoping on the 2D MoS2 by cation-cation and cation-anion pairs is also investigated. Our results demonstrate that the TM doping of 2D MoS2 leads to a significant reduction of the energy gap and the appearance of magnetic features whose major characteristic is the ferromagnetic coupling of the TM dopants. The …


On The Momentum Dependence Of The Flavor Structure Of The Nucleon Sea, Jen-Chieh Peng, Wen-Chen Chang, Hai-Yang Cheng, Tie-Jiun Hou, Keh-Fei Liu, Jian-Wei Qiu 2014 University of Illinois at Urbana-Champaign

On The Momentum Dependence Of The Flavor Structure Of The Nucleon Sea, Jen-Chieh Peng, Wen-Chen Chang, Hai-Yang Cheng, Tie-Jiun Hou, Keh-Fei Liu, Jian-Wei Qiu

Physics and Astronomy Faculty Publications

Difference between the and sea quark distributions in the proton was first observed in the violation of the Gottfried sum rule in deep-inelastic scattering (DIS) experiments. The parton momentum fraction x dependence of this difference has been measured over the region 0.02 < x < 0.35 from Drell–Yan and semi-inclusive DIS experiments. The Drell–Yan data suggested a possible sign-change for (x) − (x) near x ~ 0.3, which has not yet been explained by existing theoretical models. We present an independent evidence for the (x) − (x) sign-change at x ~ 0.3 from an analysis of the DIS data. We further discuss the x …


Theoretical And Experimental Infrared Spectra Of Hydrated And Dehydrated Sulfonated Poly(Ether Ether Ketone), Jonathan Doan, Erin Kingston, Ian Kendrick, Kierstyn Anderson, Nicholas Dimakis, Philippe Knauth, Maria Luisa Di Vona, Eugene S. Smotkina 2014 The University of Texas Rio Grande Valley

Theoretical And Experimental Infrared Spectra Of Hydrated And Dehydrated Sulfonated Poly(Ether Ether Ketone), Jonathan Doan, Erin Kingston, Ian Kendrick, Kierstyn Anderson, Nicholas Dimakis, Philippe Knauth, Maria Luisa Di Vona, Eugene S. Smotkina

Physics & Astronomy Faculty Publications

Time-dependent FT-IR spectra of sulfonated poly(ether ether ketone) during dehydration show diminishing 1081 cm−1 and 1023 cm−1 band intensities concurrent with the emergence and shifting of bands at 1362 cm−1 and 898 cm−1. Animations of density functional theory calculated normal modes enable assignment of the 1081 cm−1 and 1023 cm−1 bands as group modes that include a sulfonate exchange site with C3v local symmetry, while the 1362 cm−1 and 898 cm−1 bands are assigned as group modes that include an associated sulfonic acid with no local symmetry (C1). In contrast to analogously assigned Nafion group mode bands, the SPEEK C3v …


Model Of Electromagnetic Ion Cyclotron Waves In The Inner Magnetosphere, K. V. Gamayunov, M. J. Engebretson, M. Zhang, H. K. Rassoul 2014 Florida Institute of Technology

Model Of Electromagnetic Ion Cyclotron Waves In The Inner Magnetosphere, K. V. Gamayunov, M. J. Engebretson, M. Zhang, H. K. Rassoul

Aerospace, Physics, and Space Science Faculty Publications

he evolution of He+-mode electromagnetic ion cyclotron (EMIC) waves is studied inside the geostationary orbit using our global model of ring current (RC) ions, electric field, plasmasphere, and EMIC waves. In contrast to the approach previously used by Gamayunov et al. (2009), however, we do not use the bounce-averaged wave kinetic equation but instead use a complete, nonbounce-averaged, equation to model the evolution of EMIC wave power spectral density, including off-equatorial wave dynamics. The major results of our study can be summarized as follows. (1) The thermal background level for EMIC waves is too low to allow waves to grow …


Recent Ideas On The Calculation Of Lepton Anomalous Magnetic Moments, Michael I. Eides 2014 University of Kentucky

Recent Ideas On The Calculation Of Lepton Anomalous Magnetic Moments, Michael I. Eides

Physics and Astronomy Faculty Publications

We discuss the recent claim [G. Mishima, arXiv:1311.7109; M. Fael and M. Passera, arXiv:1402.1575 [Phys. Rev. D (to be published)]] about discovery of a nonperturbative quantum-electrodynamic contribution of order (α/π)5 to lepton anomalous magnetic moments. We explain why this nonperturbative correction does not exist.


First All-Sky Search For Continuous Gravitational Waves From Unknown Sources In Binary Systems, J. Aasi, B. P. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov 2014 The University of Texas Rio Grande Valley

First All-Sky Search For Continuous Gravitational Waves From Unknown Sources In Binary Systems, J. Aasi, B. P. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to ∼2; 254 h and a frequency- and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range …


Beam Energy Dependence Of Moments Of The Net-Charge Multiplicity Distributions In Au+Au Collisions At Rhic, J. Kevin Adkins, Renee Fatemi, Wolfgang Korsch, Suvarna Ramachandran, G. Webb, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, E. C. Aschenauer 2014 University of Kentucky

Beam Energy Dependence Of Moments Of The Net-Charge Multiplicity Distributions In Au+Au Collisions At Rhic, J. Kevin Adkins, Renee Fatemi, Wolfgang Korsch, Suvarna Ramachandran, G. Webb, L. Adamczyk, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, E. C. Aschenauer

Physics and Astronomy Faculty Publications

We report the first measurements of the moments—mean (M), variance (σ2), skewness (S), and kurtosis (κ)—of the net-charge multiplicity distributions at midrapidity in Au+Au collisions at seven energies, ranging from √SNN=7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, σ2/M, , and κσ2, with the expectations …


Dark Energy Scaling From Dark Matter To Acceleration, Jannis Bielefeld, Robert R. Caldwell, Eric Linder 2014 Dartmouth College

Dark Energy Scaling From Dark Matter To Acceleration, Jannis Bielefeld, Robert R. Caldwell, Eric Linder

Dartmouth Scholarship

The dark sector of the Universe need not be completely separable into distinct dark matter and dark energy components. We consider a model of early dark energy in which the dark energy mimics a dark matter component in both evolution and perturbations at early times. Barotropic aether dark energy scales as a fixed fraction, possibly greater than one, of the dark matter density and has vanishing sound speed at early times before undergoing a transition. This gives signatures not only in cosmic expansion but in sound speed and inhomogeneities, and in number of effective neutrino species. Model parameters describe the …


Evidence Of A Mira-Like Tail And Bow Shock About The Semi-Regular Variable V Cvn From Four Decades Of Polarization Measurements., Hilding Neilson, Richard Ignace, Beverly Smith, Gary Henson, Alyssa Adams 2014 East Tennessee State University

Evidence Of A Mira-Like Tail And Bow Shock About The Semi-Regular Variable V Cvn From Four Decades Of Polarization Measurements., Hilding Neilson, Richard Ignace, Beverly Smith, Gary Henson, Alyssa Adams

ETSU Faculty Works

Polarization is a powerful tool for understanding stellar atmospheres and circumstellar environments. Mira and semi-regular variable stars have been observed for decades and some are known to be polarimetrically variable, however, the semi-regular variable V Canes Venatici displays an unusually large, unexplained amount of polarization. We present ten years of optical polarization observations obtained with the HPOL instrument, supplemented by published observations spanning a total interval of about forty years for V CVn. We find that V CVn shows large polarization variations ranging from 1 - 6%. We also find that for the past forty years the position angle measured …


Thermal Diffusivities Of Functionalized Pentacene Semiconductors, Hao Zhang, Yulong Yao, Marcia M. Payne, John E. Anthony, Joseph W. Brill 2014 University of Kentucky

Thermal Diffusivities Of Functionalized Pentacene Semiconductors, Hao Zhang, Yulong Yao, Marcia M. Payne, John E. Anthony, Joseph W. Brill

Physics and Astronomy Faculty Publications

We have measured the interlayer and in-plane (needle axis) thermal diffusivity of 6,13-bis(triisopropylsilylethynyl) pentacene. The needle axis value is comparable to the phonon thermal diffusivities of quasi-one dimensional organic metals with excellent π-orbital overlap, and its value suggests that a significant fraction of heat is carried by optical phonons. Furthermore, the interlayer (c-axis) thermal diffusivity is at least an order of magnitude larger, and this unusual anisotropy implies very strong dispersion of optical modes in the interlayer direction, presumably due to interactions between the silyl-containing side groups. Similar values for both in-plane and interlayer diffusivities have been observed for several …


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