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Measurement of the Neutral B Meson-B Bar Meson Oscillation Frequency Using Dilepton Events at BABAR

Description: This dissertation describes the measurement of the B{sup 0}{bar B}{sup 0} oscillation frequency {Delta}m{sub d} with a sample of 122 x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric B Factory at the Stanford Linear Accelerator Center. A fully inclusive approach is used to select dilepton events in which B meson decays semileptonically and the lepton's charge is employed to identify the flavor of each B meson. The oscillation frequency {Delta}m{sub d} is extr… more
Date: June 6, 2006
Creator: Chao, Ming & /UC, Irvine
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Charm and Charmonium Spectroscopy in BaBar

Description: The BABAR experiment at the PEP-II B-factory offers excellent opportunities in charm and charmonium spectroscopy. The recent observation of new states in the D{sub s} and in the charmonium mass regions revived the interest in this field. Recent BABAR results are presented.
Date: February 6, 2008
Creator: Negrini, M. & U., /Ferrara
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiative Leptonic B Decays

Description: We present the results of a search for B{sup +} meson decays into {gamma}{ell}{sup +}{nu}{sub {ell}}, where {ell} = e,{mu}. We use a sample of 232 million B{bar B} meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction {Delta}{beta} in a restricted region of phase space that reduces the effect of theoretical uncertainties, requiring the lepton energy to be in the range 1.875 and 2.850 GeV, the photon energy to… more
Date: October 6, 2008
Creator: Chen, Edward Tann & /Caltech
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Search for Lepton Flavour Violating Decays tau- to l- Ks with the BaBar experiment

Description: A search for the lepton flavor violating decays {tau}{sup -} {yields} l{sup -} K{sub S}{sup 0} (l = e or {mu}) has been performed using a data sample corresponding to an integrated luminosity of 469 fb{sup -1}, collected with the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} asymmetric energy collider. No statistically significant signal has been observed in either channel and the estimated upper limits on branching fractions are {Beta}({tau}{sup -} {yields} e{sup -} K{sub S}{sup 0}) < … more
Date: January 6, 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
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B to (rho/omega) gamma at BaBar

Description: This document describes the measurements of the branching fractions and isospin violations of the radiative electroweak penguin decays B {yields} ({rho}/{omega}){gamma} at the asymmetric-energy e{sup +}e{sup -} PEP-II collider with the BABAR detector. Together with the previously measured branching fractions of the decays B {yields} K*{gamma} the ratio of CKM-matrix elements |V{sub td}/V{sub ts}| are extracted and the length of the far side of the unitarity triangle is determined.
Date: February 6, 2008
Creator: Koeneke, Karsten
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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D0 Silicon Upgrade: Thermal Contraction Analysis of the Solenoid and VLPC Cryogenic Transfer Lines for the D0 Upgrade

Description: The stresses developed in the solenoid and VLPC transfer lines have been investigated with the PipePlus v4.5 software package from Algor. 4 cases were considered for each transfer line and the following results were obtained. Pipe deflections have also been kept to a minimum by carefully considering the location of spider guides. Their placement should be as close as possible to the locations shown in Figures 4-7. With regard to chosen pipe sizes, the 2.5-inch OD Cu radiation shield in the sole… more
Date: June 6, 1995
Creator: Leicht, Todd M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of the D0 \to Pi Pi- Pi0 Decay at BaBar

Description: The Dalitz-plot of the decay D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} measured by the BABAR collaboration shows the structure of a final state having quantum numbers I{sup G}J{sup PC} = 0{sup -}0{sup 2-}. An isospin analysis of this Dalitz-plot finds that the fraction of the I = 0 contribution is about 96%. This high I = 0 contribution is unexpected because the weak interaction violates the isospin.
Date: April 6, 2012
Creator: Gaspero, Mario
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Selected Topics in Tau Physics from BaBar

Description: Selected results from {tau} analyses performed using the BABAR detector at the SLAC National Accelerator Laboratory are presented. A precise measurement of the {tau} mass and the {tau}{sup +}{tau}{sup -} mass difference is undertaken using the hadronic decay mode {tau}{sup {+-}} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup {+-}}{nu}{sub {tau}}. In addition an investigation into the strange decay modes {tau}{sup -} {yields} K{sub S}{sup 0}{pi}{sup -}{pi}{sup 0}{nu}{sub {tau}} and {tau}{sup -} {yields… more
Date: April 6, 2012
Creator: Paramesvaran, S. & /Royal Holloway, U. of London
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of EXO-200

Description: EXO-200 is the first phase of the Enriched Xenon Observatory (EXO) experiment, which searches for neutrinoless double beta decay in {sup 136}Xe to measure the mass and probe the Majorana nature of the neutrino. EXO-200 consists of 200 kg of liquid Xe enriched to 80% in {sup 136}Xe in an ultra-low background TPC. Energy resolution is enhanced through the simultaneous collection of scintillation light using Large Area Avalanche Photodiodes (LAAPD's) and ionization charge. It is being installed at… more
Date: December 6, 2011
Creator: Ackerman, Nicole
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Some Calculations Pertaining to Central Calorimeter Cooldown Rate and Temperature Gradients

Description: For a first-pass look at how the central calorimeter module assemblies cool down in the CC cryostat, some 'hand' calculations of free convection from the end plates were done. A local convection coefficient for heat transfer from the vertically oriented end plates to the argon gas is estimated to be about 1 x 10{sup -3} W/cm{sup 2}K. Even for free convection, flow is turbulent between the end plates and cryostat wall. Total rate of heat removal from both ends of the assembly at 300K to lOOK arg… more
Date: August 6, 1987
Creator: Peterson, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ISR Physics at BaBar

Description: A method of measuring e{sup +}e{sup -} annihilation cross sections at low energy {radical}s < 5 GeV, using initial-state radiation, is described. Experimental data from the PEP-II B-factory at 10.6 GeV center-of-mass energy, obtained via ISR, are presented. The cross sections are measured for many processes e{sup +}e{sup -} {yields} 3{pi}, 4{pi}, 2K{pi}, 2K2{pi}, 4K, p{bar p}, {Lambda}{Lambda}, D{bar D}, ... . From the measured cross sections the parameters of known resonances are improved, … more
Date: April 6, 2012
Creator: Serednyakov, S .I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

D0 Carriage Roller Bearing Measurements

Description: All of the ordered Tychoway rollers, to be used under the cryostat carriages on the center beam, have to be modified to accommodate a keyed way used to guide the cryostat along these same ways. A 0.320 x 0.406 inch notch is machined along one of the longer lower edges in order to create a 0.640 x 0.406 inch keyway when two of these notched rollers are bolted together (side by side) for installation. This keyway will fit over a .635 x .375 inch key, which is inserted into the ways. Due to the cl… more
Date: February 6, 1989
Creator: Jaques, Al
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Data Report Documenting the Rattachment of the CC Cryostat Heads

Description: Reassembly of the inner pressure vessel of a seventeen foot diameter by ten foot long double wall toroidal shaped vessel in which each vessel consists of two concentric cylinders which are capped at each end by an annular dished head. Attached drawing 1, 2, 3, and 4 (all Revision 1) show the repair work items. The work covered by this data report applies only to the inner pressure vessel (See Item 8 remarks) . These work items are: (1) Two circumferential weld seams ( Seams A and G on attached … more
Date: November 6, 1990
Creator: Luther, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

D0 Detector Collision Hall Oxygen Deficiancy Hazard Analysis

Description: EN-258, D0 Platform ODH Analysts. provided the oxygen deficiency hazard analysts for the D0 detector in the Assembly Hall. This note covers the same analysis. but revised for the Collision Hall. Liquid cryogens. released and warming to atmosphere conditions, expand to, on average, seven hundred times their liquid volume, and displace vital atmospheric oxygen. An oxygen deficiency hazard analysis assesses the increased risk to personnel in areas containing cryogenic systems. The D0 detector Coll… more
Date: August 6, 1992
Creator: Wu, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hadronic Contributions to R and G-2 from Initial-State-Radiation Data

Description: I review the recent efforts to improve the precision of the prediction of the anomalous moment of the muon, in particular of the hadronic contribution of the vacuum polarization, which is the contribution with the largest uncertainty. Focus is given to the recent result for e{sup +}e{sup -} {yields} {pi}{sup +}{pi}{sup -} by the BaBar collaboration, obtained using events with radiation in the initial state.
Date: April 6, 2012
Creator: Bernard, Denis, 1 & Polytechnique, /Ecole
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Grout Analysis for EC and CC Calorimeters

Description: The EC and CC calorimeters roll on Two parallel hardened steel ways which reside on the top of the D0 platform's center beam. The ways will be grouted to the center beam once their correct elevation has been established. The purpose of this report is to evaluate and compare three different epoxy grouts and their properties for this application.
Date: January 6, 1987
Creator: Engstrom, L.L.
Item Type: Refine your search to only Report
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
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