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2011

Series

Florida Institute of Technology

Articles 1 - 30 of 65

Full-Text Articles in Physical Sciences and Mathematics

Optical Polarization And Spectral Variability In The M87 Jet, Eric S. Perlman, Mihai Cara, Matthew Bourque, Raymond C. Simons Dec 2011

Optical Polarization And Spectral Variability In The M87 Jet, Eric S. Perlman, Mihai Cara, Matthew Bourque, Raymond C. Simons

Aerospace, Physics, and Space Science Faculty Publications

During the last decade, M87's jet has been the site of an extraordinary variability event, with one knot (HST-1) increasing by over a factor 100 in brightness. Variability has also been seen on timescales of months in the nuclear flux. Here we discuss the optical-UV polarization and spectral variability of these components, which show vastly different behavior. HST-1 shows a highly significant correlation between flux and polarization, with P increasing from 20% at minimum to >40% at maximum, while the orientation of its electric vector stayed constant. HST-1's optical-UV spectrum is very hard (αUV-O 0.5, F ν ∞ ν-α), and …

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V344 Lyrae: A Touchstone Su Uma Cataclysmic Variable In The Kepler Field, Matt A. Wood, Martin D. Still, Steve B. Howell, John K. Cannizzo, Alan P. Smale Nov 2011

V344 Lyrae: A Touchstone Su Uma Cataclysmic Variable In The Kepler Field, Matt A. Wood, Martin D. Still, Steve B. Howell, John K. Cannizzo, Alan P. Smale

Aerospace, Physics, and Space Science Faculty Publications

We report on the analysis of the Kepler short-cadence (SC) light curve of V344 Lyr obtained during 2009 June 20 through 2010 March 19 (Q2-Q4). The system is an SU UMa star showing dwarf nova (DN) outbursts and superoutbursts, and promises to be a touchstone for CV studies for the foreseeable future. The system displays both positive and negative superhumps with periods of 2.20 and 2.06 hr, respectively, and we identify an orbital period of 2.11 hr. The positive superhumps have a maximum amplitude of ~0.25 mag, the negative superhumps have a maximum amplitude of ~0.8 mag, and the orbital …

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Deep Multiwaveband Observations Of The Jets Of 0208-512 And 1202-262, Eric S. Perlman Oct 2011

Deep Multiwaveband Observations Of The Jets Of 0208-512 And 1202-262, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present deep Hubble Space Telescope, Chandra, Very Large Array, and Australia Telescope Compact Array images of the jets of PKS 0208-512 and PKS 1202-262, which were found in a Chandra survey of a flux-limited sample of flat-spectrum radio quasars with jets. We discuss in detail their X-ray morphologies and spectra. We find optical emission from one knot in the jet of PKS 1202-262 and two regions in the jet of PKS 0208-512. The X-ray emission of both jets is most consistent with external Comptonization of cosmic microwave background photons by particles within the jet, while the optical emission is …

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Mixed Monotone-Generalized Contractions In Partially Ordered Probabilistic Metric Spaces, Łjubomir B.Bomir Ćirić, Ravi P. Agarwal, Bessem Samet Sep 2011

Mixed Monotone-Generalized Contractions In Partially Ordered Probabilistic Metric Spaces, Łjubomir B.Bomir Ćirić, Ravi P. Agarwal, Bessem Samet

Mathematics and System Engineering Faculty Publications

In this article, a new concept of mixed monotone-generalized contraction in partially ordered probabilistic metric spaces is introduced, and some coupled coincidence and coupled fixed point theorems are proved. The theorems Presented are an extension of many existing results in the literature and include several recent developments. © 2011 Ćirićć et al; licensee Springer.

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Energy Spectrum Of Energetic Particles Accelerated By Shock Waves: From Focused Transport To Diffusive Acceleration, Pingbing Zuo, Ming Zhang, Konstantin V. Gamayunov, Hamid K. Rassoul, Xi Luo Sep 2011

Energy Spectrum Of Energetic Particles Accelerated By Shock Waves: From Focused Transport To Diffusive Acceleration, Pingbing Zuo, Ming Zhang, Konstantin V. Gamayunov, Hamid K. Rassoul, Xi Luo

Aerospace, Physics, and Space Science Faculty Publications

The focused transport equation (FTE) includes all the necessary physics for modeling the shock acceleration of energetic particles with a unified description of first-order Fermi acceleration, shock drift acceleration, and shock surfing acceleration. It can treat the acceleration and transport of particles with an anisotropic distribution. In this study, the energy spectrum of pickup ions accelerated at shocks of various obliquities is investigated based on the FTE. We solve the FTE by using a stochastic approach. The shock acceleration leads to a two-component energy spectrum. The low-energy component of the spectrum is made up of particles that interact with shock …

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Nicmos Polarimetry Of "Polar-Scattered" Seyfert 1 Galaxies, Daniel P. Batcheldor, Andrew Edward Robinson, David J. Axon, Stuart Young, S Quinn, James E. Smith, James H. Hough, David M. Alexander Sep 2011

Nicmos Polarimetry Of "Polar-Scattered" Seyfert 1 Galaxies, Daniel P. Batcheldor, Andrew Edward Robinson, David J. Axon, Stuart Young, S Quinn, James E. Smith, James H. Hough, David M. Alexander

Aerospace, Physics, and Space Science Faculty Publications

The nuclei of Seyfert 1 galaxies exhibit a range of optical polarization characteristics that can be understood in terms of two scattering regions producing orthogonal polarizations: an extended polar scattering region (PSR) and a compact equatorial scattering region (ESR), located within the circum-nuclear torus. Here we present NICMOS 2.0 μm imaging polarimetry of six "polar-scattered" Seyfert 1 (S1) galaxies, in which the PSR dominates the optical polarization. The unresolved nucleus (<058) is significantly polarized in only three objects, but five of the six exhibit polarization in a 058-15 circum-nuclear annulus. In Fairall 51 and ESO 323-G077, the polarization position angle at 2 μm (θ2 μm) is consistent with the average for the optical spectrum(θv), implying that the nuclear polarization is dominated by polar scattering at both wavelengths. The same is probably true for NGC3227. In both NGC 4593 and Mrk 766, there is a large difference between θ2 μm and θv off-nucleus, where polar scattering is expected to dominate. This may be due to contamination by interstellar polarization in NGC4593, but there is no clear explanation in the case of the strongly polarized Mrk766. Lastly, in Mrk1239, a large change (60°) in θ2 μm between the nucleus and the annulus indicates that the unresolved nucleus and its immediate surroundings have different polarization states at 2μm, which we attribute to the ESR and PSR, respectively. A further implication is that the source of the scattered 2 μm emission in the unresolved nucleus is the accretion disk, rather than torus hot dust emission.

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An Effect Of Perpendicular Diffusion On The Anisotropy Of Solar Energetic Particles From Unconnected Sources, Gang Qin, H. Q. He, Ming Zhang Sep 2011

An Effect Of Perpendicular Diffusion On The Anisotropy Of Solar Energetic Particles From Unconnected Sources, Gang Qin, H. Q. He, Ming Zhang

Aerospace, Physics, and Space Science Faculty Publications

Recently, Tan and coworkers studied the 2001 September 24 solar energetic particle (SEP) event observed by the Wind spacecraft at 1AU and found that there is a counter-streaming particle beam with a deep depression of flux at 90° pitch angle during the beginning of the event. They suggested that it is a result of a reflecting boundary at some distance outside of 1AU. While this scenario could be true under some specific configuration of an interplanetary magnetic field, in this paper we offer another possible explanation. We simulated the SEP event by solving the five-dimensional focused transport equation numerically for …

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Systems Of General Nonlinear Set-Valued Mixed Variational Inequalities Problems In Hilbert Spaces, Ravi P. Agarwal, Yeolje Cho, Narin Petrot Aug 2011

Systems Of General Nonlinear Set-Valued Mixed Variational Inequalities Problems In Hilbert Spaces, Ravi P. Agarwal, Yeolje Cho, Narin Petrot

Mathematics and System Engineering Faculty Publications

In this paper, the existing theorems and methods for finding solutions of systems of general nonlinear set-valued mixed variational inequalities problems in Hilbert spaces are studied. To overcome the difficulties, due to the presence of a proper convex lower semi-continuous function, φ and a mapping g, which appeared in the considered problem, we have used some applications of the resolvent operator technique. We would like to point out that although many authors have proved results for finding solutions of the systems of nonlinear set-valued (mixed) variational inequalities problems, it is clear that it cannot be directly applied to the problems …

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Nonlocal Conditions For Differential Inclusions In The Space Of Functions Of Bounded Variations, Ravi P. Agarwal, Abdelkader Boucherif Jun 2011

Nonlocal Conditions For Differential Inclusions In The Space Of Functions Of Bounded Variations, Ravi P. Agarwal, Abdelkader Boucherif

Mathematics and System Engineering Faculty Publications

We discuss the existence of solutions of an abstract differential inclusion, with a right-hand side of bounded variation and subject to a nonlocal initial condition of integral type.

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Solvability Of A Quadratic Hammerstein Integral Equation In The Class Of Functions Having Limits At Infinity, Ravi P. Agarwal, Józef Banas̈, Kamil Banas̈, Donal O'Regan Jun 2011

Solvability Of A Quadratic Hammerstein Integral Equation In The Class Of Functions Having Limits At Infinity, Ravi P. Agarwal, Józef Banas̈, Kamil Banas̈, Donal O'Regan

Mathematics and System Engineering Faculty Publications

The goal of the paper is to prove that a quadratic Hammerstein integral equation has solutions in the class of real functions denned, bounded, continuous on the real half-axis and having limits at infinity. The main tools used in our investigations are the technique of measures of noncompactness and the Darbo fixed point theorem. We provide an example illustrating our theory. © 2011 Rocky Mountain Mathematics Consortium.

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Measurement Of The B0 Production Cross Section In Pp Collisions At √S= 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov Jun 2011

Measurement Of The B0 Production Cross Section In Pp Collisions At √S= 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov

Aerospace, Physics, and Space Science Faculty Publications

Measurements of the differential production cross sections d =dpB T and d =dyB for B0 mesons produced in pp collisions at ffiffi s p ¼ 7 TeV are presented. The data set used was collected by the CMS experiment at the LHC and corresponds to an integrated luminosity of 40 pb 1. The production cross section is measured from B0 meson decays reconstructed in the exclusive final state J=c K0 S, with the subsequent decays J=c ! þ and K0 S ! þ . The total cross section for pB T > 5 GeV and jyBj < 2:2 is measured to be 33:2 2:5 3:5 b, where the first uncertainty is statistical and the second is systematic.

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Propagation Of Solar Energetic Particles In Three-Dimensional Interplanetary Magnetic Fields: In View Of Characteristics Of Sources, H. Q. He, Gang Qin, Ming Zhang Jun 2011

Propagation Of Solar Energetic Particles In Three-Dimensional Interplanetary Magnetic Fields: In View Of Characteristics Of Sources, H. Q. He, Gang Qin, Ming Zhang

Aerospace, Physics, and Space Science Faculty Publications

In this paper, a model of solar energetic particle (SEP) propagation in the three-dimensional Parker interplanetary magnetic field is calculated numerically. We study the effects of the different aspects of particle sources on the solar surface, which include the source location, coverage of latitude and longitude, and spatial distribution of source particle intensity, on propagation of SEPs with both parallel and perpendicular diffusion. We compute the particle flux and anisotropy profiles at different observation locations in the heliosphere. From our calculations, we find that the observation location relative to the latitudinal and longitudinal coverage of particle source has the strongest …

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Search For Neutral Minimal Supersymmetric Standard Model Higgs Bosons Decaying To Tau Pairs In Pp Collisions At √S = 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain Jun 2011

Search For Neutral Minimal Supersymmetric Standard Model Higgs Bosons Decaying To Tau Pairs In Pp Collisions At √S = 7 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

A search for neutral minimal supersymmetric standard model (MSSM) Higgs bosons in pp collisions at the LHC at a center-of-mass energy of 7 TeV is presented. The results are based on a data sample corresponding to an integrated luminosity of 36 pb 1 recorded by the CMS experiment. The search uses decays of the Higgs bosons to tau pairs. No excess is observed in the tau-pair invariant-mass spectrum. The resulting upper limits on the Higgs boson production cross section times branching fraction to tau pairs, as a function of the pseudoscalar Higgs boson mass, yield stringent new bounds in the …

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Improving High-Resolution Model Forecasts Of Downslope Winds In The Las Vegas Valley, Andre K. Pattantyus, Sen Chiao, Stanley Czyzyk Jun 2011

Improving High-Resolution Model Forecasts Of Downslope Winds In The Las Vegas Valley, Andre K. Pattantyus, Sen Chiao, Stanley Czyzyk

Ocean Engineering and Marine Sciences Faculty Publications

Numerical simulations for severe downslope winds as well as trapped lee waves in Nevada’s Las Vegas Valley were performed in this study. The goal of this study was to improve model forecasts of downslope wind- event intensities. This was measured by assessing different planetary boundary layer (PBL) schemes in the mountain–valley region. The Weather Research and Forecasting Model was adopted for this research. The numerical experiments were constructed using two nested domains, with 4- and 1-km grid resolution. The working hypothesis was that the occurrence of low-level wind shear and surface gustiness in the Las Vegas Valley was guided by …

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Study Of Z Boson Production In Pbpb Collisions At √Snn = 2.76 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain May 2011

Study Of Z Boson Production In Pbpb Collisions At √Snn = 2.76 Tev, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

A search for Z bosons in the þ decay channel has been performed in PbPb collisions at √sNN = 2:76 TeV with the CMS detector at the LHC, in a 7:2 b 1 data sample. The number of opposite-sign muon pairs observed in the 60–120 GeV=c2 invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of ½33:8 5:5ðstatÞ 4:4ðsystÞ 10 8, in the jyj < 2:0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.

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Search For Supersymmetry In Pp Collisions At √S = 7 Tev In Events With Two Photons And Missing Transverse Energy, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain May 2011

Search For Supersymmetry In Pp Collisions At √S = 7 Tev In Events With Two Photons And Missing Transverse Energy, S. A. Chatrchyan, V. Khachatryan, A. M. Sirunyan, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

A search for supersymmetry in the context of general gauge-mediated breaking with the lightest neutralino as the next-to-lightest supersymmetric particle and the gravitino as the lightest is presented. The data sample corresponds to an integrated luminosity of 36 pb 1 recorded by the CMS experiment at the LHC. The search is performed by using events containing two or more isolated photons, at least one hadronic jet, and significant missing transverse energy. No excess of events at high missing transverse energy is observed. Upper limits on the signal cross section for general gauge-mediated supersymmetry between 0.3 and 1.1 pb at the …

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Measurement Of Dijet Angular Distributions And Search For Quark Compositeness In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain May 2011

Measurement Of Dijet Angular Distributions And Search For Quark Compositeness In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

Dijet angular distributions are measured over a wide range of dijet invariant masses in pp collisions at ffiffi s p ¼ 7 TeV, at the CERN LHC. The event sample, recorded with the CMS detector, corresponds to an integrated luminosity of 36 pb 1. The data are found to be in good agreement with the predictions of perturbative QCD, and yield no evidence of quark compositeness. With a modified frequentist approach, a lower limit on the contact interaction scale for left-handed quarks of þ ¼ 5:6 TeV ( ¼ 6:7 TeV) for destructive (constructive) interference is obtained at the 95% …

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Editorial Announcement, Ravi P. Agarwal May 2011

Editorial Announcement, Ravi P. Agarwal

Mathematics and System Engineering Faculty Publications

[No abstract available]

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Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain May 2011

Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at ffiffi s p ¼ 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb 1. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times 2 as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at …

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Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain May 2011

Search For Pair Production Of Second-Generation Scalar Leptoquarks In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

A search for pair production of second-generation scalar leptoquarks in the final state with two muons and two jets is performed using proton-proton collision data at ffiffi s p ¼ 7 TeV collected by the CMS detector at the LHC. The data sample used corresponds to an integrated luminosity of 34 pb 1. The number of observed events is in good agreement with the predictions from the standard model processes. An upper limit is set on the second-generation leptoquark cross section times 2 as a function of the leptoquark mass, and leptoquarks with masses below 394 GeV are excluded at …

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Broad Lyα Emission From Three Nearby Bl Lacertae Objects, John T. Stocke, Charles W. Danforth, Eric S. Perlman May 2011

Broad Lyα Emission From Three Nearby Bl Lacertae Objects, John T. Stocke, Charles W. Danforth, Eric S. Perlman

Aerospace, Physics, and Space Science Faculty Publications

We present far-UV HST/COS spectra of four nearby BLLac objects. BLLac spectra are dominated by a smooth, power-law continuum which arises in a relativistic jet. However, the spectra are not necessarily featureless; weak, broad- and/or narrow-line emission is sometimes seen in high-quality optical spectra. We present detections of Lyα emission in HST/COS spectra of Mrk421 (z = 0.030) and PKS2005-489 (z = 0.071) as well as an archival HST/GHRS observation of Mrk501 (z = 0.0337). Archival HST/STIS observations of PKS2155-304 (z = 0.116) show no Lyα emission to a very low upper limit. Using the assumption that the broad-line region …

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Impulsive Semilinear Neutral Functional Differential Inclusions With Multivalued Jumps, Nadjet Abada, Ravi P. Agarwal, Mouffak Benchohra, Hadda Hammouche Apr 2011

Impulsive Semilinear Neutral Functional Differential Inclusions With Multivalued Jumps, Nadjet Abada, Ravi P. Agarwal, Mouffak Benchohra, Hadda Hammouche

Mathematics and System Engineering Faculty Publications

In this paper we establish sufficient conditions for the existence of mild solutions and extremal mild solutions for some densely defined impulsive semilinear neutral functional differential inclusions in separable Banach spaces. We rely on a fixed point theorem for the sum of completely continuous and contraction operators.

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On Random Topological Structures, Ravi P. Agarwal, Yeolje Cho, Reza Saadati Apr 2011

On Random Topological Structures, Ravi P. Agarwal, Yeolje Cho, Reza Saadati

Mathematics and System Engineering Faculty Publications

We present some topics about random spaces. The main purpose of this paper is to study topological structure of random normed spaces and random functional analysis. These subjects are important to the study of nonlinear analysis in random normed spaces.

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Poly[Aqua(L-Vinylphosphonato)- Cadmium], Douglas Andrew Knight, Laura K. Byington Congiardo, Joel T. Mague, Aaron R. Funk, Ria A. Yngard Apr 2011

Poly[Aqua(L-Vinylphosphonato)- Cadmium], Douglas Andrew Knight, Laura K. Byington Congiardo, Joel T. Mague, Aaron R. Funk, Ria A. Yngard

Chemistry and Chemical Engineering Faculty Publications

The title compound, [Cd(C 2H 3O 3P)(H 2O)] n, was obtained from vinyl-phospho-nic acid and cadmium nitrate. The vinyl groups project into the inter-lamellar space and the structure is held together via van der Waals forces. The Cd 2+ ion is six-coordinate and the geometry is best described as distorted octa-hedral, with O - Cd - O angles falling within the range 61.72 (13)-101.82 (14)°. Five of the coordinated oxygen atoms originate from the phospho-nate group and the sixth from a bound water molecule. Cd - O distances lie between 2.220 (3) and 2.394 (2) Å. The water molecule is …

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The Chromospheric Activity, Age, Metallicity, And Space Motions Of 36 Wide Binaries, Jingkun Zhao, Terry D. Oswalt, Mark J. Rudkin, Gang Zhao, Yuqin Chen Apr 2011

The Chromospheric Activity, Age, Metallicity, And Space Motions Of 36 Wide Binaries, Jingkun Zhao, Terry D. Oswalt, Mark J. Rudkin, Gang Zhao, Yuqin Chen

Aerospace, Physics, and Space Science Faculty Publications

We present the chromospheric activity (CA) levels, metallicities, and full space motions for 41 F, G, K, and M dwarf stars in 36 wide binary systems. Thirty-one of the binaries contain a white dwarf (WD) component. In such binaries, the total age can be estimated by adding the cooling age of the WD to an estimate of the progenitor's main-sequence lifetime. To better understand how CA correlates to stellar age, 14 cluster member stars were also observed. Our observations demonstrate for the first time that, in general, CA decays with age from 50 Myr to at least 8 Gyr for …

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Dijet Azimuthal Decorrelations In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov Mar 2011

Dijet Azimuthal Decorrelations In Pp Collisions At √S = 7 Tev, V. Khachatryan, A. M. Sirunyan, A. R. Tumasyan, Marc M. Baarmand, B. Dorney, S. Guragain, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov

Aerospace, Physics, and Space Science Faculty Publications

Measurements of dijet azimuthal decorrelations in pp collisions at √s=7TeV using the CMS detector at the CERN LHC are presented. The analysis is based on an inclusive dijet event sample corresponding to an integrated luminosity of 2.9pb-1. The results are compared to predictions from perturbative QCD calculations and various Monte Carlo event generators. The dijet azimuthal distributions are found to be sensitive to initial-state gluon radiation. © 2011 CERN, for the CMS Collaboration.

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Cosmic-Ray Modulation By The Global Merged Interaction Region In The Heliosheath, Xi Luo, Ming Zhang, Hamid K. Rassoul, Nikolai V. Pogorelov Mar 2011

Cosmic-Ray Modulation By The Global Merged Interaction Region In The Heliosheath, Xi Luo, Ming Zhang, Hamid K. Rassoul, Nikolai V. Pogorelov

Aerospace, Physics, and Space Science Faculty Publications

It was found by Voyager 1 and Voyager 2 that the Global Merged Interaction Region (GMIR) still has effects on cosmic-ray transport in the heliosheath. The GMIR produced by the intense solar activities of 2005 September propagated into the heliosheath in 2006, causing several decreases in the cosmic-ray flux at Voyager 1. Motivated by these observations, we investigate cosmic-ray modulation by the GMIR in the heliosheath using a three-dimensional Galactic cosmic-ray modulation code that includes the drift effect, termination shock, and a propagating GMIR. The simulation reproduces all major modulation features found by previous cosmic-ray observations in the supersonic solar …

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Measurement Of The B+ Production Cross Section In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain Mar 2011

Measurement Of The B+ Production Cross Section In Pp Collisions At √S= 7 Tev, V. Khachatryan, A. M. Sirunyan, Thomas Bergauer, Marc M. Baarmand, Marcus Hohlmann, H Kalakhety, Robert M. Ralich, Igor Vodopiyanov, B. Dorney, S. Guragain

Aerospace, Physics, and Space Science Faculty Publications

Measurements of the total and differential cross sections d =dpB T and d =dyB for Bþ mesons produced in pp collisions at ffiffi s p ¼ 7 TeV are presented. The data correspond to an integrated luminosity of 5:8 pb 1 collected by the CMS experiment operating at the LHC. The exclusive decay Bþ ! J=c Kþ, with J=c ! þ , is used to detect Bþ mesons and to measure the production cross section as a function of pB T and yB. The total cross section for pB T > 5 GeV and jyBj < 2:4 is measured to be 28:1 2:4 2:0 3:1 b, where the first uncertainty is statistical, the second is systematic, and the last is from the luminosity measurement.

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On The Existence Of Equilibrium Points, Boundedness, Oscillating Behavior And Positivity Of A Sveirs Epidemic Model Under Constant And Impulsive Vaccination, Manuel De La Sen, Ravi P. Agarwal, Asier Ibeas, Santiago Alonso-Quesada Mar 2011

On The Existence Of Equilibrium Points, Boundedness, Oscillating Behavior And Positivity Of A Sveirs Epidemic Model Under Constant And Impulsive Vaccination, Manuel De La Sen, Ravi P. Agarwal, Asier Ibeas, Santiago Alonso-Quesada

Mathematics and System Engineering Faculty Publications

This paper discusses the disease-free and endemic equilibrium points of a SVEIRS propagation disease model which potentially involves a regular constant vaccination. The positivity of such a model is also discussed as well as the boundedness of the total and partial populations. The model takes also into consideration the natural population growing and the mortality associated to the disease as well as the lost of immunity of newborns. It is assumed that there are two finite delays affecting the susceptible, recovered, exposed, and infected population dynamics. Some extensions are given for the case when impulsive nonconstant vaccination is incorporated at, …

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An X-Ray Imaging Survey Of Quasar Jets: Testing The Inverse Compton Model, Herman L. Marshall, Jonathan M. Gelbord, Daniel A. Schwartz, David W. Murphey, James E.J. Lovell, Diana M. Worrall, Mark Birkinshaw, Eric S. Perlman, Leith E.H. Godfrey, David L. Jauncey Mar 2011

An X-Ray Imaging Survey Of Quasar Jets: Testing The Inverse Compton Model, Herman L. Marshall, Jonathan M. Gelbord, Daniel A. Schwartz, David W. Murphey, James E.J. Lovell, Diana M. Worrall, Mark Birkinshaw, Eric S. Perlman, Leith E.H. Godfrey, David L. Jauncey

Aerospace, Physics, and Space Science Faculty Publications

We present results from continued Chandra X-ray imaging and spectroscopy of a flux-limited sample of flat spectrum radio-emitting quasars with jet-like extended structure. X-rays are detected from 24 of the 39 jets observed so far. We compute the distribution of αrx, the spectral index between the X-ray and radio bands, showing that it is broad, extending at least from 0.8 to 1.2. While there is a general trend that the radio brightest jets are detected most often, it is clear that predicting the X-ray flux from the radio knot flux densities is risky, so a shallow X-ray survey is the …

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