51 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Asymmetry"  
Results: 1 - 24 next
open access

Measurement of Time-Dependent CP Asymmetry in B0->ccbar K(*)0 Decays

Description: The authors present updated measurements of time-dependent Cp asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 {+-} 5) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} storage rings operating at the SLAC National Accelerator Laboratory. The time-dependent CP asymmetry parameters measured from J/{psi} K{sub S}{sup 0}, J/{p… more
Date: February 12, 2009
Creator: Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Left-Right Cross Section Asymmetry in Z Boson Production in e+e- Collisions

Description: A precise measurement of the left-right cross section asymmetry (A{sub LR}) for Z boson production by e{sup +}e{sup -} collisions has been performed at the SLAC Linear Collider with the SLD detector. Data for the 1993 run, with its significant improvements in luminosity and electron beam polarization, are presented. When combined with the (less precise) 1992 result, the preliminary result for the effective weak mixing angle is sin{sup 2} {theta}{sub W}{sup eff} = 0.2290 {+-} 0.0010.
Date: February 1, 2008
Creator: Dubois, Richard
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurements of time-dependent CP asymmetries in B0 --> D(*)+D(*)- decays

Description: We present new measurements of time-dependent CP asymmetries for B{sup 0} {yields} D{sup (*)+}d{sup (*)-} decays using (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector located at the PEP-II B Factory at the Stanford Linear Accelerator Center. We determine the CP-odd fraction of the B{sup 0} {yields} D*{sup +}D*{sup -} decays to be R{perpendicular} = 0.158 {+-} 0.028 {+-} 0.006 and find CP asymmetry parameters for the CP-even component of the decay S{sub +} = -0.76 {+-} … more
Date: February 12, 2009
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

An Asymmetric B Factory Based on PEP

Description: In this report we describe a design for a high-luminosity Asymmetric B Factory to be built in the PEP tunnel on the SLAC site. This proposal, a collaborative effort SLAC, LBL, and LLNL, is the culmination of more than two years of effort aimed at the design and construction of an asymmetric e{sup +}e{sup {minus}} collider capable of achieving a luminosity of L = 3 {times} 10{sup 33} cm{sup {minus}2} s{sup {minus}1}. The configuration adopted utilizes two storage rings, and electron ring operati… more
Date: February 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effect of nonaxisymmetric perturbations on the structure of a tokamak poloidal divertor

Description: The effects of n = 1 nonaxisymmetric perturbations on a tokamak poloidal divertor are described. Despite the existence of a region of chaotic field line trajectories outside the last closed flux surface, the footprint of the trajectories on the divertor plates is found to be largely coherent, forming a spiral structure. At a fixed toroidal angle, the footprint exhibits a bifurcation similar to that seen experimentally on DIII-D. For field errors of the magnitude that exist in present day tokama… more
Date: February 1, 1992
Creator: Pomphrey, N. & Reiman, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Physics at e sup + e sup minus factories

Description: Feasible designs are well advanced for high-luminosity e{sup +}e{sup {minus}} storage rings which produce B{sup 0}{bar B}{sup 0} pairs either at rest or, in what appears to be a more promising option, boosted in the detector frame. Facilities which could provide samples of 30--100 fb{sup {minus}1} per year on the {Upsilon}(4S) will be proposed in early 1991. Here we examine the principal physics goal of such B Factories, namely CP violation in the b system. Methods in a variety of channels, est… more
Date: February 1, 1991
Creator: Lueth, V. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)) & MacFarlane, D.B. (McGill Univ., Montreal, PQ (Canada))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effect of nonaxisymmetric perturbations on the structure of a tokamak poloidal divertor

Description: The effects of n = 1 nonaxisymmetric perturbations on a tokamak poloidal divertor are described. Despite the existence of a region of chaotic field line trajectories outside the last closed flux surface, the footprint of the trajectories on the divertor plates is found to be largely coherent, forming a spiral structure. At a fixed toroidal angle, the footprint exhibits a bifurcation similar to that seen experimentally on DIII-D. For field errors of the magnitude that exist in present day tokama… more
Date: February 1, 1992
Creator: Pomphrey, N. & Reiman, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Transversity from First Principles in QCD

Description: Transversity observables, such as the T-odd Sivers single-spin asymmetry measured in deep inelastic lepton scattering on polarized protons and the distributions which are measured in deeply virtual Compton scattering, provide important constraints on the fundamental quark and gluon structure of the proton. In this talk I discuss the challenge of computing these observables from first principles; i.e.; quantum chromodynamics, itself. A key step is the determination of the frame-independent light… more
Date: February 16, 2012
Creator: Brodsky, Stanley J. & /SLAC /Southern Denmark U., CP3-Origins
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Fast Camera Imaging of Hall Thruster Ignition

Description: Hall thrusters provide efficient space propulsion by electrostatic acceleration of ions. Rotating electron clouds in the thruster overcome the space charge limitations of other methods. Images of the thruster startup, taken with a fast camera, reveal a bright ionization period which settles into steady state operation over 50 μs. The cathode introduces azimuthal asymmetry, which persists for about 30 μs into the ignition. Plasma thrusters are used on satellites for repositioning, orbit correcti… more
Date: February 24, 2011
Creator: Ellison, C. L.; Raitses, Y. & Fisch, N. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of branching fractions of B decays to K1(1270)pi and K1(1400)pi and determination of the CKM angle alpha from B0 --> a1(1260) - pi-

Description: In the Standard Model, CP violation in weak interactions involving quarks is parameterized by an irreducible complex phase in the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing-matrix. The precise determination of the CKM elements is a necessary ingredient for a stringent test of the Standard Model predictions, and is a crucial input for reducing the theoretical error in many New Physics searches with flavor, e.g., in the kaon sector. The unitarity of the CKM matrix is typically expressed as a tr… more
Date: February 7, 2011
Creator: Stracka, Simone & /SLAC, /Milan U.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Study of CP Violation in Dalitz-Plot Analyses of B-Meson Decays to Three Kaons

Description: The Standard Model (SM) explains CP violation in terms of the CKM matrix. The BABAR experiment was designed mainly to test the CKM model in B decays. B decays that proceed through b {yields} s loop diagrams, of which B {yields} KKK decays are an example, are sensitive to new physics effects that could lead to deviations from the CKM predictions for CP violation. We present studies of CP violation in the decays B{sup +} {yields} K{sup +}K{sup -}K{sup +}, B{sup +} {yields} K{sub S}{sup 0}K{sub S}… more
Date: February 15, 2012
Creator: Lindquist, Brian
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Spin structure of the neutron ({sup 3}He) and the Bjoerken sum rule

Description: A first measurement of the longitudinal asymmetry of deepinelastic scattering of Polarized electrons from a Polarized {sup 3}He target at energies ranging from 19 to 26 GeV ha, been performed at the Stanford Linear Accelerator Center (SLAC). The spin-Structure function of the neutron g{sub 1}{sup n} has been extracted from the measured asymmetries. The Quark Parton Model (QPM) interpretation of the nucleon spin-structure function is examined in light of the new results. A test of the Ellis-Jaff… more
Date: February 1, 1994
Creator: Meziani, Z. E. & Collaboration, E-142
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of Black Carbon and Particle Number Emission Factors from Individual Heavy-Duty Trucks

Description: Emission factors for black carbon (BC) and particle number (PN) were measured from 226 individual heavy-duty (HD) diesel-fueled trucks driving through a 1 km-long California highway tunnel in August 2006. Emission factors were based on concurrent increases in BC, PN, and CO{sub 2}B concentrations (measured at 1 Hz) that corresponded to the passage of individual HD trucks. The distributions of BC and PN emission factors from individual HD trucks are skewed, meaning that a large fraction of pollu… more
Date: February 2, 2009
Creator: Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W. & Harley, Robert A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Exposing the non-collectivity in elliptic flow

Description: We show that backward-forward elliptic asymmetry correlations provide an experimentally accessible observable which distinguishes between collective and non-collective contributions to the observed elliptic asymmetry v2 in relativistic heavy ion collisions. The measurement of this observable will reveal the momentum scale at which collective expansion seizes and where the elliptic asymmetry is dominated by (semi)-hard processes. In addition, the knowledge of the actual magnitude of the collecti… more
Date: February 13, 2009
Creator: Liao, Jinfeng & Koch, Volker
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The Remarkable Similarity Between the Scaling of Kurtosis with Squared Skewness for TORPEX Density Fluctuations and Sea-surface Temperature Fluctuations

Description: The striking similarity between the statistics of plasma density fluctuations in the TORPEX device [B. Labit et al., Phys. Rev. Lett. 98, 255002 (2007)] and sea-surface temperature fluctuations [Po Sura and P. D. Sardeshmukh, J. Phys. Oceanogr. 38, 638 (2007)] (SS) is discussed. A nonlinear Langevin theory due to SS is generalized to include linear wave propagation. An interpretation of the nonlinear Langevin equation based on statistical closure theory is proposed.
Date: February 28, 2008
Creator: Krommes, John A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Macroinvertebrate Abundance and Biomass: 2007 Data, BPA-51; Preliminary Report, February 10, 2009..

Description: Four Excel files containing information on the 2007 macroinvertebrate data were initially provided to Statistical Consulting Services (SCS) by EcoAnalysts on 1/27/2009. These data files contained information on abundance and biomass data at the level of taxonomic groups. The data were subsequently reformatted and compiled, and aggregated for analysis by SCS. All descriptions and analyses below relate to this compiled data. Computations were carried out separately for each site over all sample p… more
Date: February 10, 2009
Creator: Holderman, Charles
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theoretical study of asymmetric molecular-frame photoelectron angular distributions for C 1s photoejection from CO2

Description: We report the results of ab initio calculations of cross sections and molecular-frame photoelectron angular distributions for C 1s ionization of CO2, and propose a mechanism for the recently observed asymmetry of those angular distributions with respect to the CO^+and O^+ions produced by subsequent Auger decay. The fixed-nuclei, photoionization amplitudes were constructed using variationally obtained electron-molecular ion scattering wave functions. We have also carried out electronic structure… more
Date: February 18, 2009
Creator: Rescigno, Thomas N; Miyabe, S.; McCurdy, C.W. & Orel, A.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gravi-Leptogenesis: Leptogenesis From Gravity Waves in Pseudo-Scalar Driven Inflation Models

Description: In this talk we present a mechanism for leptogenesis which is based on gravity waves produced during inflation. We show that when inflation is driven by a pseudo-scalar field the metric perturbations generated during inflation can become birefringent, therefore giving a non-vanishing contribution to the gravitational triangle anomaly and sourcing lepton anti-lepton asymmetry. As this asymmetry is sourced by the fields which are active during inflation, it is not washed out or diluted by inflati… more
Date: February 28, 2007
Creator: Alexander, S. H.; Peskin, Michael E. & Sheikh-Jabbari, M. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays

Description: We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state K{sub S}{sup 0}{pi}{sup 0}{pi}{sup 0}, with K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. We use a sample of approximately 227 million B-meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B-Factory at SLAC. From an unbinned maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.72 {+-} 0.71 {+-} 0.08 and the d… more
Date: February 6, 2007
Creator: Aubert, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of Angle beta with Time-dependent CPAsymmetry in B0 to K+K-K0 Decays

Description: In the Standard Model (SM) of particle physics, the phase of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix [1, 2] is the only source of CP violation in the quark sector. Due to the interference between mixing and decay, this phase can be observed in measurements of time-dependent CP asymmetries of B{sup 0} mesons. In the SM, CP asymmetries in b {yields} s{bar s}s decays, such as B{sup 0} {yields} K{sup +}K{sup -}K{sup 0}, are expected to be nearly equal to those observed in tree-domin… more
Date: February 15, 2007
Creator: Di Marco, Emanuele
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of the nue and Total 8B Solar Neutrino Fluxes with theSudbury Neutrino Observatory Phase I Data Set

Description: This article provides the complete description of resultsfrom the Phase I data set of the Sudbury Neutrino Observatory (SNO). ThePhase I data set is based on a 0.65 kt-year exposure of heavy water tothe solar 8B neutrino flux. Included here are details of the SNO physicsand detector model, evaluations of systematic uncertainties, andestimates of backgrounds. Also discussed are SNO's approach tostatistical extraction of the signals from the three neutrino reactions(charged current, neutral curre… more
Date: February 1, 2007
Creator: Aharmim, B.; Ahmad, Q. R.; Ahmed, S. N.; Allen, R. C.; Andersen, T. C.; Anglin, J. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Research Progress Meeting of February 19, 1948

Description: Much of the cloud chamber work has been directed toward obtaining the angular distribution of protons bombarded by deuterons from the 184-inch cyclotron. The observations have been restricted to those protons arising from neutrons of energy greater than 65 Mev. The cloud chamber used for this work is of 16-inch diruneter and employs a magnetic field of 14000 gauss. The chamber is filled with hydrogen at a pressure of 1/2 atmosphere; the vapor used is water and alchohol. Nearly 800 proton tracks… more
Date: February 19, 1948
Creator: Wakerling, R.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Phases of Augmented Hadronic Light-Front Wave Functions

Description: It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge pot… more
Date: February 15, 2010
Creator: Brodsky, Stanley J.; Pasquini, Barbara; Xiao, Bo-Wen & Yuan, Feng
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Algae Tile Data: 2004-2007, BPA-51; Preliminary Report, October 28, 2008.

Description: Multiple files containing 2004 through 2007 Tile Chlorophyll data for the Kootenai River sites designated as: KR1, KR2, KR3, KR4 (Downriver) and KR6, KR7, KR9, KR9.1, KR10, KR11, KR12, KR13, KR14 (Upriver) were received by SCS. For a complete description of the sites covered, please refer to http://ktoi.scsnetw.com. To maintain consistency with the previous SCS algae reports, all analyses were carried out separately for the Upriver and Downriver categories, as defined in the aforementioned para… more
Date: February 10, 2009
Creator: Holderman, Charles
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen