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Articles 1 - 30 of 64
Full-Text Articles in Physical Sciences and Mathematics
Interactions Of Aqueous Ag+ With Fulvic Acids: Mechanisms Of Silver Nanoparticle Formation And Investigation Of Stability, Nathaniel F. Adegboyega, Virender K. Sharma, Karolina Siskova, Radek Zboril, Mary Sohn, Brian J. Schultz, Sarbajit Banerjee
Interactions Of Aqueous Ag+ With Fulvic Acids: Mechanisms Of Silver Nanoparticle Formation And Investigation Of Stability, Nathaniel F. Adegboyega, Virender K. Sharma, Karolina Siskova, Radek Zboril, Mary Sohn, Brian J. Schultz, Sarbajit Banerjee
Chemistry and Chemical Engineering Faculty Publications
This study investigated the possible natural formation of silver nanoparticles (AgNPs) in Ag+ −fulvic acid (FA) solutions under various environmentally relevant conditions (temperature, pH, and UV light). Increase in temperature (24−90 °C) and pH (6.1−9.0) of Ag+ −Suwannee River fulvic acid (SRFA) solutions accelerated the appearance of the characteristic surface plasmon resonance (SPR) of AgNPs. The rate of AgNP formation via reduction of Ag+ in the presence of different FAs (SRFA, Pahokee Peat fulvic acid, PPFA, Nordic lake fulvic acid, NLFA) and Suwannee River humic acid (SRHA) followed the order NLFA > SRHA > PPFA > SRFA. This order was found to be …
Breaks In Thin And Thick Disks Of Edge-On Galaxies Imaged In The Spitzer Survey Of Stellar Structure In Galaxies (S4g), Sébastien Comerón, Trisha Mizusawa
Breaks In Thin And Thick Disks Of Edge-On Galaxies Imaged In The Spitzer Survey Of Stellar Structure In Galaxies (S4g), Sébastien Comerón, Trisha Mizusawa
Aerospace, Physics, and Space Science Faculty Publications
Breaks in the radial luminosity profiles of galaxies have until now been mostly studied averaged over disks. Here, we study separately breaks in thin and thick disks in 70 edge-on galaxies using imaging from the Spitzer Survey of Stellar Structure in Galaxies. We built luminosity profiles of the thin and thick disks parallel to midplanes and we found that thin disks often truncate (77%). Thick disks truncate less often (31%), but when they do, their break radius is comparable with that in the thin disk. This suggests either two different truncation mechanisms—one of dynamical origin affecting both disks simultaneously and …
Variational Methods And Critical Point Theory, Victoria Otero-Espinar, Juan J. Nieto, Donal O'Regan, Kanishka Perera
Variational Methods And Critical Point Theory, Victoria Otero-Espinar, Juan J. Nieto, Donal O'Regan, Kanishka Perera
Mathematics and System Engineering Faculty Publications
[No abstract provided]
Exploring The Effects Of Stellar Rotation And Wind Clearing: Debris Disks Around F Stars, Trisha F. Mizusawa, Luisa M. Rebull, John R. Stauffer, Geoffrey Bryden, Michael Meyer, Inseok Song
Exploring The Effects Of Stellar Rotation And Wind Clearing: Debris Disks Around F Stars, Trisha F. Mizusawa, Luisa M. Rebull, John R. Stauffer, Geoffrey Bryden, Michael Meyer, Inseok Song
Aerospace, Physics, and Space Science Faculty Publications
We have conducted a study of debris disks around F stars in order to explore correlations between rotation, stellar winds, and circumstellar disks. We obtained new 24 {mu}m photometry from the Multiband Imaging Photometer for Spitzer (MIPS) camera for a sample of 188 relatively nearby F dwarfs with various rotation rates and optical colors, and combined it with archival MIPS data for 66 more F stars, as well as Wide-field Infrared Survey Explorer data for the entire sample, plus 9 more F stars. Based on the objects' K{sub s} - [24] and [3.4] - [22] colors, we identify 22 stars …
Search For Electroweak Production Of Charginos And Neutralinos Using Leptonic Final States In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor B. Vodopiyanov
Search For Electroweak Production Of Charginos And Neutralinos Using Leptonic Final States In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor B. Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
The 2011 dataset of the CMS experiment, consisting of an integrated luminosity of 4.98 fb−1 of pp collisions at s=7" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7�=7 TeV, enables expanded searches for direct electroweak pair production of charginos and neutralinos in supersymmetric models as well as their analogs in other models of new physics. Searches sensitive to such processes, with decays to final states that contain two or more leptons, are presented. …
Search For New Physics With Long-Lived Particles Decaying To Photons And Missing Energy In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Search For New Physics With Long-Lived Particles Decaying To Photons And Missing Energy In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
A search is performed for long-lived neutral particles decaying into a photon and invisible particles. An example of such a signature is the decay of the lightest neutralino with nonzero lifetime into a gravitino and a photon in gauge-mediated supersymmetry, with the neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest. The search uses events containing photons, missing transverse energy, and jets. The impact parameter of the photon relative to the beam-beam collision point can be reconstructed using converted photons. The method is sensitive to lifetimes of the order of 0.1 to 1 ns. The data sample …
Control Of The Polytypes And Line Defects In Radiation Detector Materials, Narsingh Bahadur R. Singh, Walter M.B. Duval, Richard H. Hopkins, Robert Mazelsky, Donald K. Fox, Milton S. Gottlieb, T. Henningsen, Sam R. Coriell, Martin E. Glicksman
Control Of The Polytypes And Line Defects In Radiation Detector Materials, Narsingh Bahadur R. Singh, Walter M.B. Duval, Richard H. Hopkins, Robert Mazelsky, Donald K. Fox, Milton S. Gottlieb, T. Henningsen, Sam R. Coriell, Martin E. Glicksman
Chemistry and Chemical Engineering Faculty Publications
Experiments were performed with pure and doped lead halides to investigate growth conditions for large crystals. Direct observations during the growth of 25 mm diameter crystal growing at high velocities showed that torodial type instability is formed at the solid/liquid interface during the growth. These instabilities translate into point defects and line defects. We report the results of extensive experiments on Lead bromide doped with silver bromide to study double diffusive transport. Control of instability at the interface provides a great improvement in the quality of crystal more specifically point defects and line defects. The controlled doping controls the defects …
Periodic Structure In The Megaparsec-Scale Jet Of Pks 0637-752, L. E.H. Godfrey, E. S. Perlman
Periodic Structure In The Megaparsec-Scale Jet Of Pks 0637-752, L. E.H. Godfrey, E. S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present 18 GHz Australia Telescope Compact Array imaging of the megaparsec-scale quasar jet PKS 0637–752 with angular resolution ~0farcs58. We draw attention to a spectacular train of quasi-periodic knots along the inner 11'' of the jet, with average separation ~1.1 arcsec (7.6 kpc projected). We consider two classes of model to explain the periodic knots: those that involve a static pattern through which the jet plasma travels (e.g., stationary shocks) and those that involve modulation of the jet engine. Interpreting the knots as re-confinement shocks implies the jet kinetic power Q jet ~ 1046 erg s–1, but the constant …
A Method For Localizing Energy Dissipation In Blazars Using Fermi Variability, Amanda Dotson, Markos Georganopoulos, Demosthenes Kazanas, Eric S. Perlman
A Method For Localizing Energy Dissipation In Blazars Using Fermi Variability, Amanda Dotson, Markos Georganopoulos, Demosthenes Kazanas, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
The distance of a Fermi-detected blazar γ-ray emission site from a supermassive black hole is a matter of active debate. Here we present a method for testing if the GeV emission of powerful blazars is produced within the subparsec-scale broad-line region (BLR) or farther out in the parsec-scale molecular torus (MT) environment If the GeV emission takes place within the BLR, the inverse Compton (IC) scattering of the BLR ultraviolet (UV) seed photons that produces the γ-rays takes place at the onset of the Klein–Nishina regime. This causes the electron cooling time to become practically energy-independent and the variation of …
Self-Consistent Model Of The Interstellar Pickup Protons, Alfvenic Turbulence, And Core Solar Wind In The Outer Heliosphere, Konstantin V. Gamayunov, Ming Zhang, Nikolai V. Pogorelov, Jacob Heerikhuisen, Hamid K. Rassoul
Self-Consistent Model Of The Interstellar Pickup Protons, Alfvenic Turbulence, And Core Solar Wind In The Outer Heliosphere, Konstantin V. Gamayunov, Ming Zhang, Nikolai V. Pogorelov, Jacob Heerikhuisen, Hamid K. Rassoul
Aerospace, Physics, and Space Science Faculty Publications
A self-consistent model of the interstellar pickup protons, the slab component of the Alfvenic turbulence, and core solar wind (SW) protons is presented for r {>=} 1 along with the initial results of and comparison with the Voyager 2 (V2) observations. Two kinetic equations are used for the pickup proton distribution and Alfvenic power spectral density, and a third equation governs SW temperature including source due to the Alfven wave energy dissipation. A fraction of the pickup proton free energy, f{sub D} , which is actually released in the waveform during isotropization, is taken from the quasi-linear consideration without …
Self-Consistent Model Of The Interstellar Pickup Protons, Alfvenic Turbulence, And Core Solar Wind In The Outer Heliosphere, Konstantin V. Gamayunov, Ming Zhang, Hamid K. Rassoul, Nikolai V. Pogorelov, Jacob Heerikhuisen
Self-Consistent Model Of The Interstellar Pickup Protons, Alfvenic Turbulence, And Core Solar Wind In The Outer Heliosphere, Konstantin V. Gamayunov, Ming Zhang, Hamid K. Rassoul, Nikolai V. Pogorelov, Jacob Heerikhuisen
Aerospace, Physics, and Space Science Faculty Publications
A self-consistent model of the interstellar pickup protons, the slab component of the Alfvenic turbulence, and core solar wind (SW) protons is presented for r {>=} 1 along with the initial results of and comparison with the Voyager 2 (V2) observations. Two kinetic equations are used for the pickup proton distribution and Alfvenic power spectral density, and a third equation governs SW temperature including source due to the Alfven wave energy dissipation. A fraction of the pickup proton free energy, f{sub D} , which is actually released in the waveform during isotropization, is taken from the quasi-linear consideration without …
A Theory Of Bimodal Acceleration Of Pickup Ions By Compressive Solar Wind Turbulence Under Pressure Balance, Ming Zhang, Reinhard Schlickeiser
A Theory Of Bimodal Acceleration Of Pickup Ions By Compressive Solar Wind Turbulence Under Pressure Balance, Ming Zhang, Reinhard Schlickeiser
Aerospace, Physics, and Space Science Faculty Publications
Recently, it was demonstrated that stochastic acceleration of particles going through a series of compressive plasma waves can be efficient and fast. It could be too fast so that the pressure built up by the accelerated particles may in turn modify the amplitude of waves to prevent the particles from having an exploding pressure. We call this condition pressure balance. In this paper, we take into account the fact that active acceleration of particles only occupies a limited volume of space due to a possible intermittent nature of plasma waves or turbulence. We develop a bimodal acceleration theory that treats …
Search For A Fermiophobic Higgs Boson In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Search For A Fermiophobic Higgs Boson In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Combined results are reported from searches for a fermiophobic Higgs boson in the γγ, WW, and ZZ decay modes in proton-proton collisions at s=7" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7�=7 TeV. The explored Higgs boson mass range is 110–300 GeV. The data sample corresponds to an integrated luminosity of 4.9–5.1 fb−1. A fermiophobic Higgs boson is excluded at 95% confidence level in the mass range 110–194 GeV, and at 99% …
A Multi-Wavelength Study Of The Jet, Lobes, And Core Of The Quasar Pks 2101-490, Leith E.H. Godfrey, Eric S. Perlman
A Multi-Wavelength Study Of The Jet, Lobes, And Core Of The Quasar Pks 2101-490, Leith E.H. Godfrey, Eric S. Perlman
Aerospace, Physics, and Space Science Faculty Publications
We present a detailed study of the x-ray, optical, and radio emission from the jet, lobes, and core of the quasar PKS 2101−490 as revealed by new Chandra, Hubble Space Telescope (HST), and ATCA images. We extract the radio to x-ray spectral energy distributions from seven regions of the 13'' jet, and model the jet x-ray emission in terms of Doppler beamed inverse Compton scattering of the cosmic microwave background (IC/CMB) for a jet in a state of equipartition between particle and magnetic field energy densities. This model implies that the jet remains highly relativistic hundreds of kiloparsecs from the …
Measurement Of The Underlying Event Activity In Pp Collisions At S√=0.9 And 7 Tev With The Novel Jet-Area/Median Approach, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Measurement Of The Underlying Event Activity In Pp Collisions At S√=0.9 And 7 Tev With The Novel Jet-Area/Median Approach, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
The first measurement of the charged component of the underlying event using the novel “jet-area/median” approach is presented for proton-proton collisions at centre-of-mass energies of 0.9 and 7 TeV. The data were recorded in 2010 with the CMS experiment at the LHC. A new observable, sensitive to soft particle production, is introduced and investigated inclusively and as a function of the event scale defined by the transverse momentum of the leading jet. Various phenomenological models are compared to data, with and without corrections for detector effects. None of the examined models describe the data satisfactorily.
Simulated Lsst Survey Of Rr Lyrae Stars Throughout The Local Group, Hakeem M. Oluseyi, Christopher Culliton, Muhammad Furqan, Keri L. Hoadley, Paul Regencia, Akeem J. Wells
Simulated Lsst Survey Of Rr Lyrae Stars Throughout The Local Group, Hakeem M. Oluseyi, Christopher Culliton, Muhammad Furqan, Keri L. Hoadley, Paul Regencia, Akeem J. Wells
Aerospace, Physics, and Space Science Faculty Publications
We report on a study to determine the efficiency of the Large Synoptic Survey Telescope (LSST) to recover the periods, brightnesses, and shapes of RR Lyrae stars’ light curves in the volume extending to heliocentric distances of 1.5 Mpc. We place the smoothed light curves of 30 type ab and 10 type c RR Lyrae stars in 1007 fields across the sky, each of which represents a different realization of the LSST sampling cadences, and that sample five particular observing modes. A light curve simulation tool was used to sample the idealized RR Lyrae stars’ light curves, returning each as …
Search For A Light Charged Higgs Boson In Top Quark Decays In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor B. Vodopiyanov
Search For A Light Charged Higgs Boson In Top Quark Decays In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor B. Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Results are presented on a search for a light charged Higgs boson that can be produced in the decay of the top quark t → H+b and which, in turn, decays into τ +ν τ . The analysed data correspond to an integrated luminosity of about 2 fb−1 recorded in protonproton collisions at s=7TeV" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7TeV�=7��� by the CMS experiment at the LHC. The …
Fixed Point Theorems For Convex-Power Condensing Operators Relative To The Weak Topology And Applications To Volterra Integral Equations, Ravi P. Agarwal, Donal O'Regan, Mohamed-Aziz Taoudi
Fixed Point Theorems For Convex-Power Condensing Operators Relative To The Weak Topology And Applications To Volterra Integral Equations, Ravi P. Agarwal, Donal O'Regan, Mohamed-Aziz Taoudi
Mathematics and System Engineering Faculty Publications
In this paper we present new fixed point theorems for weakly sequentially continuous mappings which are convex-power condensing relative to a measure of weak noncompactness. Our fixed point results extend and improve several earlier works. As an application, we investigate the existence of weak solutions to a Volterra integral equation. 2012 Rocky Mountain Mathematics Consortium.
Effects Of Perpendicular Diffusion On Energetic Particles Accelerated By The Interplanetary Coronal Mass Ejection Shock, Y Wang, Gang Qin, Ming Zhang
Effects Of Perpendicular Diffusion On Energetic Particles Accelerated By The Interplanetary Coronal Mass Ejection Shock, Y Wang, Gang Qin, Ming Zhang
Aerospace, Physics, and Space Science Faculty Publications
In this work, based on a numerical solution of the focused transport equation, we obtained the intensity and anisotropy time profiles of solar energetic particles (SEPs) accelerated by an interplanetary shock in the three-dimensional Parker magnetic field. The shock is treated as a moving source of energetic particles with an assumed particle distribution function. We computed the time profiles of particle flux and anisotropy as measured by an observer at 1 AU, equatorial plane, and various longitudes with respect to the shock propagation direction. With perpendicular diffusion, energetic particles can cross magnetic field lines. Particles may be detected before the …
Measurement Of The Z/Γ* + B-Jet Cross Section In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Measurement Of The Z/Γ* + B-Jet Cross Section In Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
The production of b jets in association with a Z/γ* boson is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV and recorded by the CMS detector. The inclusive cross section for Z/γ* + b-jet production is measured in a sample corresponding to an integrated luminosity of 2.2 fb−1. The Z/γ* + b-jet cross section with Z/γ* → ℓℓ (where ℓℓ = ee or μμ) for events with the invariant mass 60 < M ℓℓ < 120 GeV, at least one b jet at the hadron level with p T > 25 GeV and |η| < 2.1, and a separation between the leptons and the jets of ΔR > 0.5 is found to …
Search For Anomalous Production Of Multilepton Events In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Search For Anomalous Production Of Multilepton Events In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
A search for anomalous production of events with three or more isolated leptons in pp collisions at s=7TeV" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7TeV�=7��� is presented. The data, corresponding to an integrated luminosity of 4.98 fb−1, were collected by the CMS experiment at the LHC during the 2011 run. The search is applicable to any model of new physics that enhances multiple lepton production. The observed multilepton events are categorized …
Shape, Transverse Size, And Charged-Hadron Multiplicity Of Jets In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Shape, Transverse Size, And Charged-Hadron Multiplicity Of Jets In Pp Collisions At S√=7tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Measurements of jet characteristics from inclusive jet production in protonproton collisions at a centre-of-mass energy of 7 TeV are presented. The data sample was collected with the CMS detector at the LHC during 2010 and corresponds to an integrated luminosity of 36 pb−1. The mean charged-hadron multiplicity, the differential and integral jet shape distributions, and two independent moments of the shape distributions are measured as functions of the jet transverse momentum for jets reconstructed with the anti-k T algorithm. The measured observables are corrected to the particle level and compared with predictions from various QCD Monte Carlo …
Empirical Determination Of Convection Parameters In White Dwarfs. I. Whole Earth Telescope Observations Of Ec14012-1446, Judith L. Provençal, Matt A. Wood, Stéphane Vennes, Péter Németh
Empirical Determination Of Convection Parameters In White Dwarfs. I. Whole Earth Telescope Observations Of Ec14012-1446, Judith L. Provençal, Matt A. Wood, Stéphane Vennes, Péter Németh
Aerospace, Physics, and Space Science Faculty Publications
We report on an analysis of 308.3 hr of high-speed photometry targeting the pulsating DA white dwarf EC14012-1446. The data were acquired with the Whole Earth Telescope during the 2008 international observing run XCOV26. The Fourier transform of the light curve contains 19 independent frequencies and numerous combination frequencies. The dominant peaks are 1633.907, 1887.404, and 2504.897μHz. Our analysis of the combination amplitudes reveals that the parent frequencies are consistent with modes of spherical degree l = 1. The combination amplitudes also provide m identifications for the largest amplitude parent frequencies. Our seismology analysis, which includes 2004–2007 archival data, confirms …
Synthesis Of A 2,2'-Bipyridyl Functionalized Oligovinylene- Phenylene Using Heck And Horner-Wadsworth-Emmons Reactions And X-Ray Crystal Structure Of E-(4-(4-Bromostyryl)Phenyl)(Methyl)Sulfane, Orsolya Karácsony, Jeffrey R. Deschamps, Scott A. Trammell, Rafaela Nita, D. Andrew Knight
Synthesis Of A 2,2'-Bipyridyl Functionalized Oligovinylene- Phenylene Using Heck And Horner-Wadsworth-Emmons Reactions And X-Ray Crystal Structure Of E-(4-(4-Bromostyryl)Phenyl)(Methyl)Sulfane, Orsolya Karácsony, Jeffrey R. Deschamps, Scott A. Trammell, Rafaela Nita, D. Andrew Knight
Chemistry and Chemical Engineering Faculty Publications
The synthesis of a new 2,2'-bipyridyl functionalized oligovinylenephenylene (OVP-5) containing a methyl protected thiol using Heck coupling and the Horner-Wadsworth- Emmons reaction and is described. A key step involving a diisopropylcarbodiimide promoted dehydration of a stable ?-hydroxyphosphonate intermediate was identified. The structure of precursor E-(4-(4-bromostyryl) phenyl)(methyl)sulfane (1) was determined using X-ray crystallography. © 2012 by the authors.
Search For Heavy Bottom-Like Quarks In 4.9 Fb−1 Of Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Search For Heavy Bottom-Like Quarks In 4.9 Fb−1 Of Pp Collisions At S√=7 Tev, The Cms Collaboration, S. Chatrchyan, V. Khachatryan, Marc M. Baarmand, B. Dorney, Marcus Hohlmann, Himali Kalakhety, Igor Vodopiyanov
Aerospace, Physics, and Space Science Faculty Publications
Results are presented from a search for heavy bottom-like quarks, pair-produced in pp collisions at s=7" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; position: relative;">s√=7�=7 TeV, undertaken with the CMS experiment at the LHC. The b′ quarks are assumed to decay exclusively to tW. The b′b¯′→tW−t¯W+" role="presentation" style="box-sizing: inherit; display: inline; line-height: normal; word-spacing: normal; overflow-wrap: normal; text-wrap: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; …
The Kepler Light Curves Of V1504 Cygni And V344 Lyrae: A Study Of The Outburst Properties, John K. Cannizzo, Alan P. Smale, Matt A. Wood, Martin D. Still, Steve B. Howell
The Kepler Light Curves Of V1504 Cygni And V344 Lyrae: A Study Of The Outburst Properties, John K. Cannizzo, Alan P. Smale, Matt A. Wood, Martin D. Still, Steve B. Howell
Aerospace, Physics, and Space Science Faculty Publications
We examine the Kepler light curves of V1504 Cyg and V344 Lyr, encompassing ~736 days at one-minute cadence. During this span each system exhibited ~64–65 outbursts, including 6 superoutbursts. We find that, in both systems, the normal outbursts lying between two superoutbursts increase in duration over time by a factor ~1.2–1.9, and then reset to a small value after the following superoutburst. In both systems the trend of quiescent intervals between normal outbursts is to increase to a local maximum about halfway through the supercycle—the interval from one superoutburst to the next—and then to decrease back to a small value …
Observational Constraints On The Degenerate Mass-Radius Relation, Jay B. Holberg, Terry D. Oswalt, M A. Barstow
Observational Constraints On The Degenerate Mass-Radius Relation, Jay B. Holberg, Terry D. Oswalt, M A. Barstow
Aerospace, Physics, and Space Science Faculty Publications
The white dwarf mass-radius relationship is fundamental to modern astrophysics. It is central to routine estimation of DA white dwarf masses derived from spectroscopic temperatures and gravities. It is also the basis for observational determinations of the white dwarf initial-final-mass relation. Nevertheless, definitive and detailed observational confirmations of the mass-radius relation (MRR) remain elusive owing to a lack of sufficiently accurate white dwarf masses and radii. Current best estimates of masses and radii allow only broad conclusions about the expected inverse relation between masses and radii in degenerate stars. In this paper, we examine a restricted set of 12 DA …
The Initial-Final Mass Relation Among White Dwarfs In Wide Binaries, Jingkun Zhao, T. D. Oswalt, Lee Anne Wilson, Qian Wang, Gang Zhao
The Initial-Final Mass Relation Among White Dwarfs In Wide Binaries, Jingkun Zhao, T. D. Oswalt, Lee Anne Wilson, Qian Wang, Gang Zhao
Aerospace, Physics, and Space Science Faculty Publications
We present the initial–final mass relation derived from 10 white dwarfs in wide binaries that consist of a main-sequence star and a white dwarf. The temperature and gravity of each white dwarf were measured by fitting theoretical model atmospheres to the observed spectrum using a χ2 fitting algorithm. The cooling time and mass were obtained using theoretical cooling tracks. The total age of each binary was estimated from the chromospheric activity of its main-sequence component to an uncertainty of about 0.17 dex in log t. The difference between the total age and white dwarf cooling time is taken as the …
The 2010 Very High Energy Y-Ray Flare And 10 Years Of Multi-Wavelength Observations Of M 87, A. Abramowski, Mihai Cara, Eric S. Perlman, The H.E.S.S. Collaboration, The Magic Collaboration
The 2010 Very High Energy Y-Ray Flare And 10 Years Of Multi-Wavelength Observations Of M 87, A. Abramowski, Mihai Cara, Eric S. Perlman, The H.E.S.S. Collaboration, The Magic Collaboration
Aerospace, Physics, and Space Science Faculty Publications
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 – 6) × 109 M ☉) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) γ-ray emission generated in relativistic outflows and the surroundings of supermassive black holes. M 87 has been established as a VHE γ-ray emitter since 2006. The VHE γ-ray emission displays strong variability on timescales as short as a day. In this paper, results from a joint VHE monitoring campaign on M 87 by the MAGIC and VERITAS instruments in …
Fragile Binary Candidates In The Sdss Dr8 Spectroscopic Archive, J K. Zhao, Terry D. Oswalt, G Zhao
Fragile Binary Candidates In The Sdss Dr8 Spectroscopic Archive, J K. Zhao, Terry D. Oswalt, G Zhao
Aerospace, Physics, and Space Science Faculty Publications
We present a catalog of 80 very wide fragile binary candidates (projected separations >10,000 AU) from the Sloan Digital Sky Survey Data Release Eight spectral archive. The pairs were selected based on proper motion, radial velocity, metallicity, and photometric parallax criteria. The angular separations of these pairs range from 3" to 250 ". The peak in the metallicity distribution of these pairs is about −0.5 dex of solar metallicity. Space motions and reduced proper motion diagrams indicate that all these pairs are members of the disk. The chromospheric activity index SHK of each component in 38 binary candidates having spectra …