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The CKM matrix and the unitarity triangle. Proceedings, workshop, Geneva, Switzerland, February 13-16, 2002

Description: This report contains the results of the Workshop on the CKM Unitarity Triangle that was held at CERN on 13-16 February 2002. There had been several Workshops on B physics that concentrated on studies at e{sup +}e{sup -} machines, at the Tevatron, or at LHC separately. Here we brought together experts of different fields, both theorists and experimentalists, to study the determination of the CKM matrix from all the available data of K, D, and B physics. The analysis of LEP data for B physics is reaching its end, and one of the goals of the Workshop was to underline the results that have been achieved at LEP, SLC, and CESR. Another goal was to prepare for the transfer of responsibility for averaging B physics properties, that has developed within the LEP community, to the present main actors of these studies, from the B factory and the Tevatron experiments. The optimal way to combine the various experimental and theoretical inputs and to fit for the apex of the Unitarity Triangle has been a contentious issue. A further goal of the Workshop was to bring together the proponents of different fitting strategies, and to compare their approaches when applied to the same inputs. Since lattice QCD plays a very important role in the determination of the non-perturbative parameters needed to constrain the CKM unitarity triangle, the first Workshop was seen as an excellent opportunity to bring together lattice theorists with the aim of establishing a working group to compile averages for phenomenologically relevant quantities. Representatives from lattice collaborations around the world were invited to attend a meeting during the Workshop. A consensus was reached to set up three test working groups, collectively known as the ''CKM Lattice Working Group'', to review a number of well-studied quantities: quark masses, the kaon B-parameter, ...
Date: April 2, 2004
Creator: Battaglia, M.; Buras, A. J.; Gambino, P. & Stocchi, A.
Partner: UNT Libraries Government Documents Department

ULTRAHIGH ENERGY NEUTRINOS, SMALL X AND UNITARITY.

Description: The ultrahigh energy cross section for neutrino interactions with nucleons is reviewed, and unitarity constraints are discussed. We argue that existing QCD extrapolations are self-consistent, and do not imply a breakdown of the perturbative expansion in the weak coupling.
Date: June 30, 2001
Creator: Hall Reno, M.; Sarcevic, I. N.; Sterman, G.; Stratmann, M. & Vogelsang, W.
Partner: UNT Libraries Government Documents Department

MEASUREMENTS OF DIRECT CP VIOLATION AND CONSTRAINT ON THE CKM TRIANGLE IN B->K*pi DECAYS

Description: We constrain the apex of the Cabibbo-Kobayashi-Maskawa unitarity triangle with measurements of B {yields} K*{pi} amplitudes from analyses of B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} and B{sup 0} {yields} K{sub S}{pi}{sup +}{pi}{sup -} decays. This constraint is consistent with the world average. The B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} decay mode is reconstructed from a sample of 454 million B{sup 0}{bar B}{sup 0} events collected by the BABAR detector at SLAC. We measure direct CP violation in B{sup 0} {yields} K*{sup +}{pi}{sup -} decays at the level of 3{sigma} when measurements from both B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} and B{sup 0} {yields} K{sub S}{pi}{sup +}{pi}{sup -} decays are combined.
Date: April 29, 2010
Creator: Wagner, Andrew Phillips
Partner: UNT Libraries Government Documents Department

Unitarity Triangle Angle Measurements at BaBar

Description: We present recent results of measurements of the Unitarity Triangle angles alpha, beta and gamma made with the BaBar detector at the PEP-II asymmetric B factory. We present recent results of measurements of the Unitarity Triangle angles alpha, beta and gamma made with the BaBar detector at the PEP-II asymmetric B factory.
Date: June 30, 2005
Creator: Latham, Thomas E.
Partner: UNT Libraries Government Documents Department

New Measurements of the Angle Gamma at the BabarExperiment

Description: Measuring the angle {gamma} is an important part of over-constraining the Unitarity Triangle to test Standard Model predictions. There are a number of methods to measure {gamma}, and we present results on the progress made in measuring {gamma} with B meson decays, using data collected with the BABAR detector at the PEP-II asymmetric energy e{sup +}e{sup -} collider at SLAC.
Date: November 7, 2007
Creator: Orimoto, Toyoko Jennifer
Partner: UNT Libraries Government Documents Department

CKM-UT Angles: Mixing And CP Violation at the B Factories

Description: We review the experimental status of the angles of the Unitarity Triangle of the CKM matrix, as measured by the BABAR and Belle experiments. The B Factories have demonstrated since the beginning of this decade that CP violation in the B meson system is consistent with the Standard Model (SM) description in terms of the complex phase in the three-by-three Cabibbo-Kobayashi-Maskawa (CKM) matrix. With one single phase, the SM predicts clear patterns for quark mixing and CP violations, to be satisfied by all processes.
Date: November 7, 2011
Creator: Finocchiaro, Giuseppe
Partner: UNT Libraries Government Documents Department

Search for b->u Transitions inB- -> D0 K- and B- -> D*0 K-

Description: The authors search for B{sup -} {yields} {tilde D}{sup 0}K{sup -} and B{sup -} {yields} {tilde D}*{sup 0}K{sup -}, with {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{pi}{sup 0} or {tilde D}*{sup 0} {yields} {tilde D}{sup 0}{gamma}, and {tilde D}{sup 0} {yields} K{sup +}{pi}{sup -} (and charge conjugates). These final states can be reached through the b {yields} c transition B{sup -} {yields} D{sup (*)0}K{sup -} followed by the doubly CKM-suppressed D{sup 0} {yields} K{sup +}{pi}{sup -}, or the b {yields} u transition B{sup -} {yields} {bar D}{sup (*)0}K{sup -} followed by the CKM-favored {bar D}{sup 0} {yields} K{sup +}{pi}{sup -}. The interference of these two amplitudes is sensitive to the angle {gamma} of the unitarity triangle. The results are based on 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at SLAC. They find no significant evidence for these decays. They set a limit r{sub B} {triple_bond} |A(B{sup -} {yields} {bar D}{sup 0}K{sup -})/A(B{sup -} {yields} D{sup 0}K{sup -})| < 0.23 at 90% C.L. using the most conservative assumptions on the values of the CKM angle {gamma} and the strong phases in the B and D decay amplitudes. In the case of the D* they set a 90% C.L. limit r*{sub B}{sup 2} {triple_bond} |A(B{sup -} {yields} {bar D}*{sup 0}K{sup -})/A(B{sup -} {yields} D*{sup 0} K{sup -})|{sup 2} < (0.16){sup 2} which is independent of assumptions on {gamma} and strong phases.
Date: May 27, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Partner: UNT Libraries Government Documents Department

SuperB: a Linear High-Luminosity B Factory

Description: This paper is based on the outcome of the activity that has taken place during the recent workshop on ''SuperB in Italy'' held in Frascati on November 11-12, 2005. The workshop was opened by a theoretical introduction of Marco Ciuchini and was structured in two working groups. One focused on the machine and the other on the detector and experimental issues.. The present status on CP is mainly based on the results achieved by BABAR and Belle. Establishment of the indirect CP violation in B sector in 2001 and of the direct CP violation in 2004 thanks to the success of PEP-II and KEKB e{sup +}e{sup -} asymmetric B Factories operating at the center of mass energy corresponding to the mass of the {Upsilon}(4S ). With the two B Factories taking data, the Unitarity Triangle is now beginning to be over constrained by improving the measurements of the sides and now also of the angles {alpha}, and {gamma}. We are also in presence of the very intriguing results about the measurements of sin2{beta} in the time dependent analysis of decay channels via penguin loops, where b {yields} s{bar s}s and b {yields} s{bar d}d. {tau} physics, in particular LFV search, as well as charm and ISR physics are important parts of the scientific program of a SuperB Factory. The physics case together with possible scenarios for the high luminosity SuperB Factory based on the concepts of the Linear Collider and the related experimental issues are discussed.
Date: February 8, 2006
Creator: Albert, J.; Bettarini, S.; Biagini, M.; Bonneaud, G.; Cai, Y.; Calderini, G. et al.
Partner: UNT Libraries Government Documents Department

Full one-loop amplitudes from tree amplitudes

Description: We establish an efficient polynomial-complexity algorithm for one-loop calculations, based on generalized D-dimensional unitarity. It allows automated computations of both cut-constructible and rational parts of one-loop scattering amplitudes from on-shell tree amplitudes. We illustrate the method by (re)-computing all four-, five- and six-gluon scattering amplitudes in QCD at one-loop.
Date: January 1, 2008
Creator: Giele, Walter T.; Kunszt, Zoltan & Melnikov, Kirill
Partner: UNT Libraries Government Documents Department

CP Violation at BaBar

Description: We report recent measurements of the three CKM angles of the Unitarity Triangle using about 383 millions b{bar b} pairs collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The results of the angles ({beta}, {alpha}, {gamma}) of the unitarity triangle are consistent with Belle results, and with other CKM constraints such as the measurement of {epsilon}{sub K}, the length of the sides of the unitarity triangle determined from the measurements of {Delta}m{sub d}, {Delta}m{sub s}, |V{sub ub}|. This is an impressive confirmation of Standard Model in quark-flavor sector.
Date: November 15, 2011
Creator: Yeche, Christophe
Partner: UNT Libraries Government Documents Department

SEARCH FOR NEW PHYSICS AT A SUPER-B FACTORY.

Description: The importance of a Super-B Factory in the search for New Physics, in particular, due to CP-od phase(s) from physics beyond the Standard Model is surveyed. The first point to emphasize is that we know now how to directly measure all three angles of the unitarity triangle very cleanly, i. e. without theoretical assumptions with irreducible theory error {le} 1%; however this requires much more luminosity than is currently available at B-factories. Direct searches via penguin-dominated hadronic modes as well as radiative, pair-leptonic and semi-leptonic decays are also discussed. Null tests of the SM are stressed as these will play a crucial role especially if the effects of BSM phase(s) on B-physics are small.
Date: January 5, 2004
Creator: BROWDER,T. E. & SONI,A.
Partner: UNT Libraries Government Documents Department

An Alternative View of the Dynamical Origin of the P11 Nucleon Resonances: Results from the Excited Baryon Analysis Center

Description: We present an alternative interpretation for the dynamical origin of the P{sub 11} nucleon resonances, which results from the dynamical coupled-channels analysis at Excited Baryon Analysis Center of Jefferson Lab. The results indicate the crucial role of the multichannel reaction dynamics in determining the N* spectrum. An understanding of the spectrum and structure of the excited nucleon (N*) states is a fundamental challenge in the hadron physics. The N* states, however, couple strongly to the meson-baryon continuum states and appear only as resonance states in the {gamma}N and {pi}N reactions. One can expect from such strong couplings that the (multichannel) reaction dynamics will affect significantly the N* states and cannot be neglected in extracting the N* parameters from the data and giving physical interpretations. It is thus well recognized nowadays that a comprehensive study of all relevant meson production reactions with {pi}N,{eta}N,{pi}{pi}N,KY, {hor_ellipsis} final states is necessary for a reliable extraction of the N* parameters. To address this challenging issue, the Excited Baryon Analysis Center (EBAC) of Jefferson Lab has been conducting the comprehensive analysis of the world data of {gamma}N,{pi}N {yields} {pi}N,{eta}N,{pi}{pi}N,KY, {hor_ellipsis} reactions systematically, covering the wide energy and kinematic regions. The analysis is pursued with a dynamical coupled-channels (DCC) model, the EBAC-DCC model, within which the unitarity among relevant meson-baryon channels, including the three-body {pi}{pi}N channel, is fully taken into account.
Date: April 1, 2012
Creator: Kamano, Hiroyuki
Partner: UNT Libraries Government Documents Department

Semileptonic B to D Decays at Nonzero Recoil with 2+1 Flavors of Improved Staggered Quarks

Description: The Fermilab Lattice-MILC collaboration is completing a comprehensive program of heavy-light physics on the MILC (2+1)-flavor asqtad ensembles with lattice spacings as small as 0.045 fm and light-to-strange-quark mass ratios as low as 1/20. We use the Fermilab interpretation of the clover action for heavy valence quarks and the asqtad action for light valence quarks. The central goal of the program is to provide ever more exacting tests of the unitarity of the CKM matrix. We give a progress report on one part of the program, namely the analysis of the semileptonic decay B to D at both zero and nonzero recoil. Although final results are not presented, we discuss improvements in the analysis methods, the statistical errors, and the parameter coverage that we expect will lead to a significant reduction in the final error for |V{sub cb}| from this decay channel.
Date: November 1, 2011
Creator: Qiu, Si-Wei; U., /Utah; DeTar, Carleton; U., /Utah; Du, Daping; U., /Iowa et al.
Partner: UNT Libraries Government Documents Department

BaBar: sin(2beta+gamma)

Description: The time-dependent CP asymmetries in fully reconstructed B{sup 0} {yields} D{sup (*){+-}}{pi}{sup {-+}}/{rho}{sup {-+}} decays (new preliminary result), and in partially reconstructed B{sup 0} {yields} D{sup (*){+-}}{pi}{sup {-+}} decays, are measured with the BABAR detector at the PEP-II asymmetric B factory at SLAC, using 232 million {Upsilon}(4S) {yields} B{bar B} decays. We combine the above results and, using other measurements and theoretical assumptions, they interpret them in terms of the angles of the unitarity triangle describing the Cabibbo-Kobayashi-Maskawa matrix. They find |sin(2{beta} + {gamma})| > 0.64(0.42) at 68%(90%) confidence level using a frequentistic approach and |2{beta}+ {gamma}| = (90 {+-} 43){sup o} using a Bayesian approach.
Date: January 11, 2006
Creator: Voena, Cecilia & /Rome U. /INFN, Rome
Partner: UNT Libraries Government Documents Department

CP Violation at BaBar

Description: Several new and updated BABAR measurements of sin 2{beta} are presented, together with the latest constraints on the Unitarity Triangle angles {alpha} and {gamma}. The higher statistics now available allow more sophisticated analysis techniques, such as time-dependent Dalitz plot fitting. Combined world-average results place tight constraints on the Unitarity Triangle. There is good agreement among the measurements and with the unitarity of the CKM matrix. This represents an impressive verification of the Standard Model description of the quark-flavor sector and of CP violation.
Date: January 8, 2008
Creator: Hawkes, Chris & U., /Birmingham
Partner: UNT Libraries Government Documents Department

Measurement of CP-Violating Asymmetries in B0 to (rho pi)0 using a Time-Dependent Dalitz Plot Analysis

Description: We report a measurement of CP-violating asymmetries in B{sup 0} {yields} ({rho}{pi}){sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0} decays using a time-dependent Dalitz plot analysis. The results are obtained from a data sample of 375 million {Upsilon}(4S) {yields} B{bar B} decays, collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We measure 26 coefficients of the bilinear form-factor terms occurring in the time-dependent decay rate of the B{sup 0} meson. We derive the physically relevant quantities from these coefficients. In particular, we measure a constraint on the angle {alpha} of the Unitarity Triangle.
Date: March 6, 2007
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

CKM Parameters and Rare B Decays

Description: Measurements of the angles and sides of the unitarity triangle and of the rates of rare B meson decays are crucial for the precise determination of Standard Model parameters and are sensitive to the presence of new physics particles in the loop diagrams. In this paper the recent measurements performed in this area by BABAR and Belle will be presented. The direct measurement of the angle {alpha} is for the first time as precise as the indirect determination. The precision of the |V{sub ub}| determination has improved significantly with respect to previous measurement. New limits on B {yields} {tau}{nu} decays are presented, as well as updated measurements on b {yields} s radiative transitions and a new observation of b {yields} d{gamma} transition made by Belle.
Date: December 14, 2005
Creator: Forti, Francesco & /INFN, Pisa
Partner: UNT Libraries Government Documents Department

Results from the B Factories

Description: These proceedings are based on lectures given at the Helmholtz International Summer School Heavy Quark Physics at the Bogoliubov Laboratory of Theoretical Physics, Dubna, Russia, during August 2008. I review the current status of CP violation in B meson decays from the B factories. These results can be used, along with measurements of the sides of the Unitarity Triangle, to test the CKM mechanism. In addition I discuss experimental studies of B decays to final states with 'spin-one' particles.
Date: January 8, 2009
Creator: Bevan, A. & /Queen Mary, U. of London
Partner: UNT Libraries Government Documents Department

Three-Loop Superfiniteness of N=8 Supergravity

Description: We construct the three-loop four-point amplitude of N = 8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments, render its degree of divergence in D dimensions to be no worse than that of N = 4 super-Yang-Mills theory--a finite theory in four dimensions. Similar cancellations can be identified at all loop orders in certain unitarity cuts, suggesting that N = 8 supergravity may be a perturbatively finite theory of quantum gravity.
Date: February 20, 2007
Creator: Bern, Z.; Carrasco, J.J.; Dixon, L.J.; Johansson, H.; Kosower, D.A. & Roiban, R.
Partner: UNT Libraries Government Documents Department

Operational measure of entanglement based on experimental consequences.

Description: The maximum eigenvalue of the real part of the density matrix expressed in a maximally entangled basis with a particular phase relationship can be used as an operational measure of entanglement. This measure is related to the fidelity, maximized with a local unitary operating on either subsystem, of a standard dense coding, teleportation, or entanglement swapping protocol.
Date: January 1, 2002
Creator: Grondalski, J. P. (John P.) & James, D. F. (Daniel F.)
Partner: UNT Libraries Government Documents Department

Measurements of Branching Ratios And Search for CP Violation in the Modes B0 to Rho Pi, Rho K

Description: The BABAR experiment, at the PEP-II collider at SLAC, has been studying since 1999 CP violation in the B meson system. After the precise measurement of sin2{beta}, one is now concentrating on measuring the angles {alpha} and {gamma} of the unitarity triangle. The work presented in this thesis concerns the measurement of the angle {alpha} in the B{sup 0} {yields} {rho}{pi} mode.
Date: September 18, 2006
Creator: Laplace, Sandrine & /Paris U., VI-VII
Partner: UNT Libraries Government Documents Department

Measurement of Time-dependent CP Asymmetries inB0->D(*)pi and B0->Drho Decays

Description: We present updated results on time-dependent CP asymmetries in fully reconstructed B{sup 0} {yields} D{sup (*){+-}}{pi}{sup {-+}} and B{sup 0} {yields} D{sup {+-}}{rho}{sup {-+}} decays in approximately 232 million {Upsilon}(4S) {yields} B{bar B} events collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. From a time-dependent maximum likelihood fit we obtain for the parameters related to the CP violation angle 2{beta} + {gamma}: a{sup D{pi}} = -0.010 {+-} 0.023 {+-} 0.007, c{sub lep}{sup D{pi}} = -0.033 {+-} 0.042 {+-} 0.012, a{sup D*{pi}} = -0.040 {+-} 0.023 {+-} 0.010, C{sub lep}{sup D*{pi}} = 0.049 {+-} 0.042 {+-} 0.015, a{sup D{rho}} = -0.024 {+-} 0.031 {+-} 0.009, c{sub lep}{sup D{rho}} = -0.098 {+-} 0.055 {+-} 0.018, where the first error is statistical and the second is systematic. Using other measurements and theoretical assumptions, we interpret the results in terms of the angles of the Cabibbo-Kobayashi-Maskawa unitarity triangle and find |sin(2{beta}+{gamma})| > 0.64 (0.40) at 68% (90%) confidence level.
Date: March 3, 2006
Creator: Aubert, B.
Partner: UNT Libraries Government Documents Department

Taste violations in the scalar correlator in mixed action simulations

Description: We study the behavior of the isovector scalar correlator, which is particularly sensitive to lattice artifacts, using domain-wall valence quarks on a staggered sea (generated by the MILC collaboration). We analyze this according to the prediction from chiral perturbation theory determined by Prelovsek, which indicates that the leading unitarity violations come from taste breaking effects. We show that our data behaves in the way predicted by Prelovsek, thus verifying that the largest contribution to the violations of unitarity which arise at finite lattice spacing can be described by the mixed-action chiral perturbation theory.
Date: October 1, 2007
Creator: Aubin, C.; Coll., /Columbia U. /William-Mary; Laiho, Jack; /Fermilab /Washington U., St. Louis; Van de Water, Ruth S. & /Fermilab
Partner: UNT Libraries Government Documents Department