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in subjects: "Fluctuations"  
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Cygnus PFL Switch Jitter

Description: The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources: Cygnus 1 and Cygnus 2. Each source has the following X-ray output: 1-mm diameter spot size, 4 rads at 1 m, 50-ns full-widthhalf-maximum. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests p… more
Date: July 21, 2007
Creator: Mitton, C.; Corrow, G. & Henderson, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic and thermal properties of high Tc superconductors

Description: Measurements of the normal state magnetic susceptibility {chi}(T) of YBa{sub 2}Cu{sub 3}O{sub 7}, Bi{sub 1.8}Pb{sub 0.2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}}, and Bi{sub 2{minus}x}Pb{sub x}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10+{delta}} (x = 0.2 and 0.25) were carried out. All {chi}(T) data show negative curvature below {approximately}2{Tc}. The data for YBa{sub 2}Cu{sub 3}O{sub 7} are in excellent agreement with a new calculation of the superconducting fluctuation diamagnetism. From the analysis, … more
Date: September 21, 1990
Creator: Lee, Wonchoon
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Beam Energy and System Size Dependence of Dynamical Net Charge Fluctuations

Description: We present measurements of net charge fluctuations in Au + Au collisions at {radical}s{sub NN} = 19.6, 62.4, 130, and 200 GeV, Cu + Cu collisions at {radical}s{sub NN} = 62.4, 200 GeV, and p + p collisions at {radical}s = 200 GeV using the dynamical net charge fluctuations measure {nu}{sub {+-},dyn}. We observe that the dynamical fluctuations are non-zero at all energies and exhibit a modest dependence on beam energy. A weak system size dependence is also observed. We examine the collision cent… more
Date: July 21, 2008
Creator: STAR Collaboration
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Length of Time's Arrow

Description: An unresolved problem in physics is how the thermodynamic arrow of time arises from an underlying time reversible dynamics. We contribute to this issue by developing a measure of time-symmetry breaking, and by using the work fluctuation relations, we determine the time asymmetry of recent single molecule RNA unfolding experiments. We define time asymmetry as the Jensen-Shannon divergencebetween trajectory probability distributions of an experiment and its time-reversed conjugate. Among other in… more
Date: August 21, 2008
Creator: Feng, Edward H. & Crooks, Gavin E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A System for Simulating Fluctuation Diagnostics for Application to Turbulence Computations

Description: Present-day nonlinear microstability codes are able to compute the saturated fluctuations of a turbulent fluid versus space and time, whether the fluid be liquid, gas, or plasma. They are therefore able to determine turbulence-induced fluid (or particle) and energy fluxes. These codes, however, must be tested against experimental data, not only with respect to transport, but also characteristics of the fluctuations. The latter is challenging because of limitations in the diagnostics (e.g., fini… more
Date: February 21, 2006
Creator: Bravenec, R V & Nevins, W M
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling the Mechano-Chemistry of NTPases

Description: This project is to develop theoretical framework for protein motors based on experimental data. Protein motors use chemical and electrochemical energies to perform mechanical work. Protein motors are machines of life. They are essential for many biological processes, including cell division, DNA transcription, replication, etc. Understanding the working mechanisms of protein motors has both scientific and medical/clinical significances, including revealing the physiological origins of certain d… more
Date: February 21, 2007
Creator: Xing, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electron Bernstein Wave Emission and Mode Conversion Physics on NSTX

Description: NSTX is a spherical tokamak (ST) that operates with ne up to 1020 m-3 and BT less than 0.6 T, cutting off low harmonic electron cyclotron (EC) emission widely used for Te measurements on conventional aspect ratio tokamaks. The electron Bernstein wave (EBW) can propagate in ST plasmas and is emitted at EC harmonics. These properties suggest thermal EBW emission (EBE) may be used for local Te measurements in the ST. Practically, a robust Te(R,t) EBE diagnostic requires EBW transmission efficienci… more
Date: May 21, 2008
Creator: Diem, S J; Caughman, J B; Efthimion, P; Kugel, H; LeBlanc, B P; Preinhaelter, J et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Observation of Energetic Particle Driven Modes Relevant to Advanced Tokamak Regimes

Description: Measurements of high-frequency oscillations in JET [Joint European Torus], JT-60U, Alcator C-Mod, DIII-D, and TFTR [Tokamak Fusion Test Reactor] plasmas are contributing to a new understanding of fast ion-driven instabilities relevant to Advanced Tokamak (AT) regimes. A model based on the transition from a cylindrical-like frequency-chirping mode to the Toroidal Alfven Eigenmode (TAE) has successfully encompassed many of the characteristics seen in experiments. In a surprising development, the … more
Date: October 21, 2004
Creator: Nazikian, R.; Alper, B.; Berk, H. L.; Borba, D.; Boswell, C.; Budny, R. V. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Detection of RF Perturbations Using an Ion Beam Diagnostic

Description: A Heavy Ion Beam Probe, HIBP, has been installed on a helicon plasma device. The objective was to measure plasma fluctuations at the 13.55MHz RF frequency. This offers a unique challenge for the HIBP, because the transit time of the probing ion is long compared to the fluctuations of interest. For previous HIBPs, the transit time has been short compared to the period of the fluctuations which permits one to assume that the magnetic and electric fields are static. Modeling has shown that the dia… more
Date: September 21, 2005
Creator: Schoch, P.; Connor, K. & Si, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The direct limit on the Higgs Mass and the SM Fit

Description: Because of two 3{sigma} anomalies, the Standard Model (SM) fit of the precision electroweak data has a poor confidence level, CL = 0.02. Since both anomalies involve challenging systematic issues, it might appear that the SM could still be valid if the anomalies resulted from underestimated systematic error. Indeed the CL of the global fit could then increase to 0.71, but that fit predicts a small Higgs boson mass, m{sub H} = 45 GeV, that is inconsistent at 95% CL with the lower limit, m{sub H}… more
Date: April 21, 2003
Creator: Chanowitz, Michael S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fluid Effects on Shear Waves in FInely Layered Porous Media

Description: Although there are five effective shear moduli for any layered VTI medium, one and only one effective shear modulus for the layered system contains all the dependence of pore fluids on the elastic or poroelastic constants that can be observed in vertically polarized shear waves. Pore fluids can increase the magnitude the shear energy stored by this modulus by a term that ranges from the smallest to the largest shear moduli of the VTI system. But, since there are five shear moduli in play, the i… more
Date: May 21, 2004
Creator: Berger, E. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Implications of Pulser Voltage Ripple

Description: In a recent set of measurements obtained by G. Kamin, W. Manning, A. Molvik, and J. Sullivan, the voltage waveform of the diode pulser had a ripple of approximately {+-}1.3% of the 65 kV flattop voltage, and the beam current had a larger corresponding ripple of approximately {+-}8.4% of the 1.5 mA average current at the location of the second Faraday cup, approximately 1.9 m downstream from the ion source. The period of the ripple was about 1 {mu}s. It was initially unclear whether this large c… more
Date: December 21, 2011
Creator: Barnard, J J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fluctuation Results Fro PHENIX.

Description: The PHENIX Experiment at the Relativistic Heavy Ion Collider has made measurements of event-by-event fluctuations in the net charge, the mean transverse momentum, and the charged particle multiplicity as a function of collision energy, centrality, and transverse momentum in heavy ion collisions. The results of these measurements will be reviewed and discussed.
Date: April 21, 2005
Creator: Mitchell, J. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cosmological parameters and power spectrum from peculiar velocities

Description: The power spectrum of mass density fluctuations is evaluated from the Mark III and the SFI catalogs of peculiar velocities by a maximum likelihood analysis, using parametric models for the power spectrum and for the errors. The applications to the two different data sets, using generalized CDM models with and without COBE normalization, give consistent results. The general result is a relatively high amplitude of the power spectrum, with {sigma}{sub 8}{Omega}{sub m}{sup 0.6} = 0.8 {+-} 0.2 at 9… more
Date: September 21, 1999
Creator: Zehavi, Idit
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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