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A reduced order model for the study of asymmetries in linear gas chromatography for homogeneous tubular columns.

Description: In gas chromatography, a chemical sample separates into its constituent components as it travels along a long thin column. As the component chemicals exit the column they are detected and identified, allowing the chemical makeup of the sample to be determined. For correct identification of the component chemicals, the distribution of the concentration of each chemical along the length of the column must be nearly symmetric. The prediction and control of asymmetries in gas chromatography has bee… more
Date: August 1, 2005
Creator: Whiting, Joshua J.; Romero, Louis Anthony & Parks, Michael L.
Partner: UNT Libraries Government Documents Department
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Study of the decay asymmetry parameter and CP violation parameter in the Lambda(c)+ ---> Lambda pi+ decay

Description: Using data from the FOCUS (E831) experiment at Fermilab, we present a new measurement of the weak decay-asymmetry parameter a{sub {Lambda}{sub c}} in {Lambda}{sub c}{sup +} {yields} {Lambda}{pi}{sup +} decay. Comparing particle with antiparticle decays, we obtain the first measurement of the CP violation parameter {Alpha} {triple_bond} a{sub {Lambda}{sub c}} + a{sub {ovr {Lambda}{sub c}}}/a{sub {Lambda}{sub c}} - a{sub {ovr {Lambda}{sub c}}}. We obtain a{sub {Lambda}{sub c}} = -0.78 {+-} 0.16 {… more
Date: September 1, 2005
Creator: Link, J. M.; Yager, P. M.; /UC, Davis; Anjos, J. C.; Bediaga, I.; Castromonte, C. et al.
Partner: UNT Libraries Government Documents Department
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Physics of heavy flavor at CDF

Description: Results on physics of heavy flavor at CDF are reported. Selected measurements of Branching Ratios and CP asymmetry in B{sup 0} and B{sub s}{sup 0}, lifetime difference of B{sub s}{sup 0} CP eigenstates and a precise measurement of the B{sub c} mass are presented.
Date: June 1, 2005
Creator: Torre, Stefano & /Siena U. /INFN, Pisa
Partner: UNT Libraries Government Documents Department
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A Measurement of the K0 charge radius and a CP violating asymmetry together with a search for CP violating e1 direct photon emission in the rare decay K(L) ---> pi+ pi- e+ e-

Description: Using the complete KTeV data set of 5241 candidate K{sub L} {yields} {pi}{sup +}{pi}{sup -}e{sup +}e{sup -} decays (including an estimated background of 204 {+-} 14 events), we have measured the coupling g{sub CR} = 0.163 {+-} 0.014 (stat) {+-} 0.023 (syst) of the CP conserving charge radius process and from it determined a K{sup 0} charge radius of <r{sub K{sup 0}}{sup 2}> = (-0.077 {+-} 0.007(stat) {+-} 0.011(syst))fm{sup 2}. We have also determined a first experimental upper limit of 0… more
Date: August 1, 2005
Creator: Abouzaid, E.; Arenton, M.; Barker, A. R.; Bellantoni, L.; Bellavance, A.; Blucher, E. et al.
Partner: UNT Libraries Government Documents Department
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Measurement of the Analyzing Power in PP Elastic Scattering in the Peak CNI Region at RHIC

Description: The analyzing power A{sub N} for pp elastic scattering is expected to reach a peak value of 0.045 in the Coulomb Nuclear Interference (CNI) region at a momentum transfer -t of 0.003 (GeV/c){sup 2}. During the 2004 RHIC Run, we completed a measurement of A{sub N} in the CNI region by detecting the recoil protons from pp elastic scattering using a polarized atomic hydrogen gas jet target and the 100 GeV RHIC proton beam. We report the first measurements of the A{sub N} absolute value and shape in… more
Date: January 28, 2005
Creator: Makdisi, Y.; Okada, H.; Alekseev, I. G.; Bravar, A.; Bunce, G. & AL, ET
Partner: UNT Libraries Government Documents Department
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The New Minimal Standard Model

Description: We construct the New Minimal Standard Model that incorporates the new discoveries of physics beyond the Minimal Standard Model (MSM): Dark Energy, non-baryonic Dark Matter, neutrino masses, as well as baryon asymmetry and cosmic inflation, adopting the principle of minimal particle content and the most general renormalizable Lagrangian. We base the model purely on empirical facts rather than aesthetics. We need only six new degrees of freedom beyond the MSM. It is free from excessive flavor-cha… more
Date: January 13, 2005
Creator: Davoudiasl, Hooman; Kitano, Ryuichiro; Li, Tianjun & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department
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Tevatron results

Description: Recent results obtained by the CDF and D0 experiments at the Tevatron Run II are presented. A first part is dedicated to QCD physics where inclusive jet production, dijet azimuthal decorrelations and jet shapes measurements are reported. Electroweak physics is then discussed relating measurements of the W and Z bosons productions, of the forward-backward charge asymmetry in W production, of the W width and of the top quarks mass. The extensive Run II exploration program is finally approached re… more
Date: January 1, 2005
Creator: Lefevre, R.
Partner: UNT Libraries Government Documents Department
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Large-Area Balloon-Borne Polarized Gamma Ray Observer (PoGO)

Description: We are developing a new balloon-borne instrument (PoGO), to measure polarization of soft gamma rays (30-200 keV) using asymmetry in azimuth angle distribution of Compton scattering. PoGO is designed to detect 10% polarization in 100mCrab sources in a 6-8 hour observation and bring a new dimension to studies on gamma ray emission/transportation mechanism in pulsars, AGNs, black hole binaries, and neutron star surface. The concept is an adaptation to polarization measurements of well-type phoswic… more
Date: June 30, 2005
Creator: Andersson, V.; Chen, P.; Kamae, T.; Madejski, G.; Mizuno, T.; Ng, J. et al.
Partner: UNT Libraries Government Documents Department
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Lipid asymmetry in DLPC/DSPC supported lipid bilayers, a combined AFM and fluorescence microscopy study

Description: A fundamental attribute of cell membranes is transmembrane asymmetry, specifically the formation of ordered phase domains in one leaflet that are compositionally different from the opposing leaflet of the bilayer. Using model membrane systems, many previous studies have demonstrated the formation of ordered phase domains that display complete transmembrane symmetry but there have been few reports on the more biologically relevant asymmetric membrane structures. Here we report on a combined atom… more
Date: June 20, 2005
Creator: Lin, W; Blanchette, C D; Ratto, T V & Longo, M L
Partner: UNT Libraries Government Documents Department
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Measurement of the B+- --> rho+- pi0 Branching Fraction and Direct CP Asymmetry

Description: An improved measurement of the process B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0} is presented. The data sample of 211 fb{sup -1} comprises 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The yield and CP asymmetry are calculated using an extended maximum likelihood fitting method. The branching fraction and asymmetry are found to be {Beta}(B{sup {+-}} {yields} {rho}{sup {+-}}{pi}{sup 0}) = [10.0 {+-} 1.4 (Sta… more
Date: June 29, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
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Cation distribution in a Fe-bearing K-feldspar from Itrongay,Madagascar. A combined neutron- and X-ray single crystal diffractionstudy

Description: We determined the cation distribution and ordering of Si, Al and Fe on the tetrahedral sites of a monoclinic low-sanidine from Itrongay, Madagascar, by combined neutron- and X-ray single-crystal diffraction. The cation distribution was determined by means of a simultaneous refinement using neutron- and X-ray data, as well as by combining scattering densities obtained from separate refinements with chemical data from a microprobe experiment. The two methods give the same results and show that Fe… more
Date: May 2, 2005
Creator: Ackermann, Sonia; Kunz, Martin; Armbruster, Thomas; Schefer,Jurg & Hanni, Henry
Partner: UNT Libraries Government Documents Department
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Branching Fraction And Direct CP Violating Asymmetries in Charmless Twobody B Decays at BaBar

Description: We present preliminary measurements of branching fractions and direct CP violating asymmetries in charmless two-body B decays, obtained with the BABAR detector using a sample of 227M {Upsilon}(4S) {yields} B{bar B} decays. We report the first observation of B{sup 0} {yields} K{sup 0}{bar K}{sup 0} and the first observation of direct CP violation in B{sup 0} {yields} K{sup +}{pi}{sup -} decays.
Date: November 4, 2005
Creator: Hulsbergen, W.D.
Partner: UNT Libraries Government Documents Department
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Phenomenological Theory of the Kink Instability in a Slender Plasma Column

Description: When one deals with a plasma column whose radius a is much smaller than its length L, one can think of it as of a thin filament whose kink instability can be adequately described simply by a 2D displacement vector, {xi}{sub x} = {xi}{sub s}(z,t); {xi}{sub y} = {xi}{sub y}(z,t). Details of the internal structure of the column such as the current, density, and axial flow velocity distribution would be lumped into some phenomenological parameters. This approach is particularly efficient in the pro… more
Date: November 18, 2005
Creator: Ryutov, D. D.; Furno, I.; Intrator, T. P.; Abbate, S. & Madziwa-Nussinov, T.
Partner: UNT Libraries Government Documents Department
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Measurement of single spin asymmetry and fifth structure function for the proton(electron vec, electron Kaon+)Lambda reaction with CEBAF Large Acceptance Spectrometer (CLAS)

Description: The single spin asymmetry, A{sub LT} ?, and the polarized structure function, ?{sub LT}?, for the p(e,e?K{sup +})? reaction in the resonance region have been measured and extracted using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were taken at an electron beam energy of 2.567 GeV. The large acceptance of CLAS allows for full azimuthal angle coverage over a large range of center-of-mass scattering angles. Results were obtained that span a range in Q{sup 2} from 0.5 to … more
Date: August 31, 2005
Creator: Nasseripour, Rahksha
Partner: UNT Libraries Government Documents Department
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Measurement of Branching Fraction and CP-Violating Asymmetry for B-> omega K0s

Description: The authors present a preliminary measurement of the branching fraction and CP-violating parameters S and C for the decay B{sup 0} {yields} {omega}K{sub S}{sup 0}. The data sample corresponds to 232 x 10{sup 6} B{bar B} pairs produced from e{sup +}e{sup -} annihilation at the {Upsilon}(4S) resonance. They measure {Beta}(B{sup 0} {yields} {omega}K{sup 0}) = (5.9 {+-} 1.0 {+-} 0.4) x 10{sup -6}, S = 0.50{sub -0.38}{sup +0.34} {+-} 0.02 and C = -0.56{sub -0.27}{sup +0.29} {+-} 0.03.
Date: June 8, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department
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Pseudorapidity Asymmetry and Centrality Dependence of Charged Hadron Spectra in d+Au collisions at sqrt(sNN) = 200 GeV

Description: The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at {radical}s{sub NN} = 200 GeV are presented. The charged particle density at mid-rapidity, its pseudorapidity asymmetry and centrality dependence are reasonably reproduced by a Multi-Phase Transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for p{sub T} below 5 GeV/c. … more
Date: January 12, 2005
Creator: Adams, J.; Aggarwal, M. M.; Ahammed, Z.; Amonett, J.; Anderson, B. D.; Arkhipkin, D. et al.
Partner: UNT Libraries Government Documents Department
open access

SGPGET: AN SBDART Module for Aerosol Radiative Transfer

Description: Quantification of the aerosol direct effect and climate sensitivity requires accurate estimates of optical properties as inputs to a radiative transfer model. Long-term measurements of aerosol properties at the Southern Great Plains (SGP) site can be used as an improvement over a best guess or global average for optical properties (e.g., asymmetry factor of 0.7) used in Atmospheric Radiation Measurement (ARM) products such as the Broadband Heating Rate Profile VAP. To make this information read… more
Date: March 18, 2005
Creator: McComiskey, A.; Ricchiazzi, P.; Ogren, J.A. & Dutton, E.
Partner: UNT Libraries Government Documents Department
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Final Technical Report

Description: The purpose of this grant was to experimentally investigate asymmetry-induced radial transport in a non-neutral (Penning-Malmberg) plasma trap. These traps provide an excellent platform for transport studies since the plasmas are generally well confined. One can then study transport in a controlled manner: the plasma is perturbed and the resulting transport measured. The focus of this research is the transport produced by applied asymmetric electric fields. The main results of our research conc… more
Date: March 28, 2005
Creator: Eggleston, Dennis L.
Partner: UNT Libraries Government Documents Department
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COMPARING EXTRACTIONS OF SIVERS FUNCTIONS.

Description: A comparison is given of the various recently published extractions of the Sivers functions from the HERMES and COMPASS data on single-transverse spin asymmetries in semi-inclusive deeply inelastic scattering.
Date: September 7, 2005
Creator: VOGELSANG, W.
Partner: UNT Libraries Government Documents Department
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Improvement in Clouds and the Earth's Radiant Energy System/Surface and Atmosphere Radiation Budget Dust Aerosol Properties, Effects on Surface Validation of Clouds and Radiative Swath

Description: Within the Clouds and the Earth's Radiant Energy System (CERES) science team (Wielicki et al. 1996), the Surface and Atmospheric Radiation Budget (SARB) group is tasked with calculating vertical profiles of heating rates, globally, and continuously, beneath CERES footprint observations of Top of Atmosphere (TOA) fluxes. This is accomplished using a fast radiative transfer code originally developed by Qiang Fu and Kuo-Nan Liou (Fu and Liou 1993) and subsequently highly modified by the SARB team.… more
Date: March 18, 2005
Creator: Rutan, D.; Rose, F. & Charlock, T. P.
Partner: UNT Libraries Government Documents Department
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Electroweak physics: measurement of the forward-backward charge asymmetry of electron-positron pairs in p anti-p collisions at s**(1/2) = 1.96 tev

Description: We report a measurement of the forward-backward charge asymmetry of electrons from W boson decays in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample of 170 pb{sup -1} collected by the Collider Detector at Fermilab. The asymmetry is measured as a function of electron rapidity and transverse energy and provides new input on the momentum fraction dependence of the u and d quark parton distribution functions within the proton.
Date: February 23, 2005
Creator: Acosta, D.
Partner: UNT Libraries Government Documents Department
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Two Dimensional Power Spectral Density Measurements of X-Rayoptics With the Micromap Interferometric Microscope

Description: A procedure and software have been developed to transform the area distribution of the residual surface heights available from the measurement with the Micromap interferometric microscope into a two-dimensional (2D) power spectral density (PSD) distribution of the surface height. The procedure incorporates correction of one of the spectral distortions of the PSD measurement. The distortion appears as a shape difference between the tangential and sagittal PSD spectra deduced from the 2D PSD dist… more
Date: May 12, 2005
Creator: Yashchuk, Valeriy V.; Franck, Andrew D.; C., Irick Steve; Howells,Malcolm R.; MacDowell, Alastair A. & McKinney, Wayne R.
Partner: UNT Libraries Government Documents Department
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A Molecular-Thermodynamic Lattice Model for Binary Mixtures

Description: Using a method originally proposed for describing a continuum-space polymer fluid, a new expression for the Helmholtz energy of mixing is proposed for a binary lattice mixture. Molecular size asymmetry and nonrandomness due to segment-segment interactions are taken into account. An expression proposed by Yan, Liu and Hu for a binary lattice mixture of monomers, based on the Ising model, is used as a reference system. Calculated critical constants and liquid-liquid coexistence curves are in good… more
Date: April 29, 2005
Creator: Qin, Yuan & Prausnitz, John M.
Partner: UNT Libraries Government Documents Department
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