Theoretical And Experimental Infrared Spectra Of Hydrated And Dehydrated Sulfonated Poly(Ether Ether Ketone), 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, N. Dimakis, Philippe Knauth, Maria Luisa Di Vona, Eugene S. Smotkina
Physics and Astronomy Faculty Publications and Presentations
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 …
Recent Ideas On The Calculation Of Lepton Anomalous Magnetic Moments, 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.
Model Of Electromagnetic Ion Cyclotron Waves In The Inner Magnetosphere, 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 …
Direct Measurement Of The Pp Solar Neutrino Interaction Rate In Borexino, 2014 University of Massachusetts Amherst
Direct Measurement Of The Pp Solar Neutrino Interaction Rate In Borexino, Keith Otis
Doctoral Dissertations
This dissertation presents the first direct detection of pp solar neutrinos within Borexino, the underground liquid-scintilator detector located at the Gran Sasso National Labratory(LNGS) in Italy, designed to measure the interaction of neutrinos through neutrino-electron elastic scattering. The rate of scattering in Borexino from the pp solar neutrino spectrum is measured to be 155 +/- 16(stat) +/- 13(sys) counts per day per 100 tonnes. With this measurement we are able to rule out the no oscillation hypothesis at the 2-sigma C.L. and the results agree with Standard Solar Model predictions within 1.1-sigma. These neutrinos are from the keystone proton-proton fusion …
Measures Of Star Formation Rates Within Galaxies: The Impact Of Diffuse Stellar Populations, 2014 University of Massachusetts Amherst
Measures Of Star Formation Rates Within Galaxies: The Impact Of Diffuse Stellar Populations, Yiming Li
Doctoral Dissertations
Thanks to the Spitzer Space Telescope, the infrared (IR) emission have been better studied in the past decades, as well as its relations to star formation rates (SFR) and the calibrations of IR emissions as SFR indicators. However, the far infrared (FIR) emission are still understudied, especially at the sub-galactic region scales. In this dissertation, I present new ground--based observations in the light of the infrared hydrogen recombination line Br[gamma] (2.16~mu m) of a sample of KINGFISH (Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel) galaxies. The Br[gamma] emission line offers the double advantage of directly tracing ionizing …
Beam Energy Dependence Of Moments Of The Net-Charge Multiplicity Distributions In Au+Au Collisions At Rhic, 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, Sσ, and κσ2, with the expectations …
Dark Energy Scaling From Dark Matter To Acceleration, 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 …
Comparative Analysis Of A Transition Region Bright Point With A Blinker And Coronal Bright Point Using Multiple Eis Emission Lines, 2014 Trinity University
Comparative Analysis Of A Transition Region Bright Point With A Blinker And Coronal Bright Point Using Multiple Eis Emission Lines, N Orange, H Oluseyi, D Chesny, M Patel, K Hesterly, L Preuss, C Neira, Niescja Turner
Niescja E. Turner
Since their discovery 20 year ago, transition region bright points have never been observed spectroscopically. Bright point properties have not been compared with similar transition region and coronal structures. In this work we have investigated three transient quiet Sun brightenings including a transition region bright point (TR BP), a coronal bright point (CBP) and a blinker. We use time-series observations of the extreme-ultraviolet emission lines of a wide range of temperature T(logT=5.3 – 6.4) from the EUV Imaging Spectrometer (EIS) onboard the Hinode satellite. We present the EIS temperature maps and Doppler maps, which are compared with magnetograms from theMichelson …
Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, 2014 KAUST
Intensities, Broadening And Narrowing Parameters In The Ν3 Band Of Methane, Et-Touhami Es-Sebbar, Aamir Farooq
Dr. Et-touhami Es-sebbar
The P-branch of methane׳s ν3 band is probed to carry out an extensive study of the 2905–2908 cm−1 infrared spectral region. Absolute line intensities as well as N2-, O2-, H2-, He-, Ar- and CO2-broadening coefficients are determined for nine transitions at room temperature. Narrowing parameters due to the Dicke effect have also been investigated. A narrow emission line-width (~0.0001 cm−1) difference-frequency-generation (DFG) laser system is used as the tunable light source. To retrieve the CH4 spectroscopic parameters, Voigt and Galatry profiles were used to simulate the measured line shape of the individual transitions.
Sic Particles From Asymptotic Giant Branch Stars: Mg Burning And The S-Process, 2014 Clemson University
Sic Particles From Asymptotic Giant Branch Stars: Mg Burning And The S-Process, Lawrence E. Brown, Donald D. Clayton
Donald D Clayton
The question of whether isotopically anomalous SiC particles found in meteorites originate in AGB stars is addressed. It is shown that if the peak helium shell flash temperatures of massive (6-9 solar masses) stars are about 10 percent larger than they are normally assumed to be, alpha particle reactions with the magnesium will become significant. Then the (Mg-29)(alpha, n)Si-29 reaction produces a large excess of Si-29. With a light element nuclear reaction network, the evolution of the silicon isotopic composition during AGB evolution is calculated. It is found that the experimentally determined correlation between excess Si-29 and excess Si-30 in …
Growth Of Carbon Grains In Supernova Ejecta, 2014 College of Charleston
Growth Of Carbon Grains In Supernova Ejecta, Ethan Deneault, Donald Clayton, Bradley Meyer
Donald D Clayton
We present a chemical reaction network that describes the condensation chemistry of carbon dust grains in an expanding supernova shell. We assume that the region of interest consists solely of gaseous free carbon and oxygen atoms and that the buildup of CO is counteracted by the radioactive decay of 56Co, which breaks up the CO mol-ecule and allows C to condense into solids. Our chemical model takes C to first form linear chains, which, at some critical length, transition into ringed isomers. These isomers are more resistant to oxidation than linear chains. These ringed isomers form the nuclei for the …
Supernova Reverse Shocks: Sic Growth And Isotopic Composition, 2014 Clemson University
Supernova Reverse Shocks: Sic Growth And Isotopic Composition, Ethan A-N. Deneault, Donald D. Clayton, Alexander Heger
Donald D Clayton
We present new mechanisms by which the isotopic compositions of X-type grains of presolar SiC are altered by reverse shocks in Type II supernovae. We address three epochs of reverse shocks: pressure wave from the H envelope near t ¼ 106 s, reverse shock from the presupernova wind near 108–109 s, and reverse shock from the interstellar medium near 1010 s. Using one-dimensional hydrodynamics we show that the first creates a dense shell of Si and C atoms near 106 s in which the SiC surely condenses. The second reverse shock causes precondensed grains to move rapidly forward through decelerated …
Are Ti44-Producing Supernovae Exceptional?, 2014 Clemson University
Are Ti44-Producing Supernovae Exceptional?, L.-S. The, Donald Clayton, R Diehl, Dieter Hartmann, A Iyudin, M Leising, B Meyer, Y Motizuki, V Schönfelder
Donald D Clayton
According to standard models supernovae produce radioactive 44Ti, which should be visible in gamma-rays following decay to 44Ca for a few centuries. 44Ti production is believed to be the source of cosmic 44Ca, whose abundance is well established. Yet, gamma-ray telescopes have not seen the expected young remnants of core collapse events. The 44Ti mean life of 89 y and the Galactic supernova rate of 3/100 y imply several detectable 44Ti gamma-ray sources, but only one is clearly seen, the 340-year-old Cas A SNR. Furthermore, supernovae which produce much 44Ti are expected to occur primarily in the inner part of …
Evidence Of A Mira-Like Tail And Bow Shock About The Semi-Regular Variable V Cvn From Four Decades Of Polarization Measurements., 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 …
Evidence Of A Mira-Like Tail And Bow Shock About The Semi-Regular Variable V Cvn From Four Decades Of Polarization Measurements., 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 R. Neilson, Richard Ignace, Beverly J. Smith, Gary Henson, Alyssa M. Adams
Richard Ignace
Thermal Diffusivities Of Functionalized Pentacene Semiconductors, 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 …
Detailed Abundances Of The Solar Twins 16 Cygni And B Cygni: Constraining Planet Formation Models, 2014 National Optical Astronomy Observatory
Detailed Abundances Of The Solar Twins 16 Cygni And B Cygni: Constraining Planet Formation Models, Simon C. Schuler, Katia Cunha, Verne V. Smith, Luan Ghezzi, Jeremy R. King, Constantine P. Deliyannis, Ann Merchant Boesgaard
Jeremy R King
Results of a detailed abundance analysis of the solar twins 16 Cyg A and 16 Cyg B based on high-resolution, high signal-to-noise ratio echelle spectroscopy are presented. 16 Cyg B is known to host a giant planet while no planets have yet been detected around 16 Cyg A. Stellar parameters are derived directly from our high-quality spectra, and the stars are found to be physically similar, with ΔTeff = +43 K, Δ log g =−0.02 dex, and Δξ = +0.10 km s−1 (in the sense of A − B), consistent with previous findings. Abundances of 15 elements are derived and …
The Li Overabundance Of J37: Diffusion Or Accretion?, 2014 Keele University
The Li Overabundance Of J37: Diffusion Or Accretion?, J F. Ashwell, R D. Jeffries, C P. Deliyannis, A Steinhauer, Jeremy R. King
Jeremy R King
In September 2002 the discovery of a super Li-rich F-dwarf (J37) in NGC 6633, an iron poor analogue of the better studied Hyades and Praecepe open clusters, was announced. This unique star was thought to be the smoking gun for the action of diffusion, models of which predict a narrow ”Li-peak” at approximately the correct temperature. However, with more detailed studies into J37s abundance pattern this star provides firm evidence for the accretion of planetesimals or other material from the circumstellar environment of new born stars. Thanks to the specific predictions made about the behaviour of Be abundances, (the most …
The Correlation Of Lithium And Beryllium In F And G Cluster Dwarf Stars, 2014 University of Hawaii
The Correlation Of Lithium And Beryllium In F And G Cluster Dwarf Stars, Ann Merchant Boesgaard, Eric Armengaud, Constantine P. Deliyannis, Alex Stephens, Jeremy R. King
Jeremy R King
Although Li has been extensively observed in main-sequence field and cluster stars, there are relatively fewer observations of Be. We have obtained Keck HIRES spectra of 36 late F and early G dwarfs in order to study the Li-Be correlation we found previously in the temperature regime of 5900–6650 K. The sample size for this temperature range with detectable and (usually) depleted Li and Be is now 88, including Li and Be abundances in both cluster and field stars. Therefore we can now investigate the influence of other parameters such as age, temperature, and metallicity on the correlation. The Be …
A Spectroscopic Analysis Of The Eclipsing Short-Period Binary V505 Persei And The Origin Of The Lithium Dip, 2014 Clemson University
A Spectroscopic Analysis Of The Eclipsing Short-Period Binary V505 Persei And The Origin Of The Lithium Dip, Patrick Baugh, Jeremy R. King, Constantine P. Deliyannis, Ann Merchant Boesgaard
Jeremy R King
As a test of rotationally-induced mixing causing the well-known Li dip in older mid-F dwarfs in the local Galactic disk, we utilize high-resolution and -S/N Keck/HIRES spectroscopy to measure the Li abundance in the components of the ∼1 Gyr, [Fe/H]= −0.15 eclipsing short-period binary V505 Per. We find A(Li) ∼ 2.7 ± 0.1 and 2.4 ± 0.2 in the Teff∼6500 and 6450K primary and sec-ondary components, respectively. Previous Teff determinations and uncertainties suggest that each component is located in the midst of the Li dip. If so, their A(Li) are ≥2–5 times larger than A(Li) detections and upper limits observed …