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Book Improved Measurement of the CP Violating Asymmetry Amplitude Sin2beta

Download or read book Improved Measurement of the CP Violating Asymmetry Amplitude Sin2beta written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present updated results on time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 62 million [Upsilon](4S) [yields] B[bar B] decays collected between 1999 and 2001 by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. In this sample we study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2[beta], is derived from the decay time distributions in such events. We measure sin2[beta] = 0.75 [+-] 0.09 (stat) [+-] 0.04 (syst) and lambda = 0.92 [+-] 0.06 (stat) [+-] 0.02 (syst). The latter is consistent with the Standard Model expectation of no direct CP violation. These results are preliminary.

Book Measurement of the CP Violating Asymmetry Amplitude Sin2b

Download or read book Measurement of the CP Violating Asymmetry Amplitude Sin2b written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results on time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 88 million [Upsilon](4S) → B{bar B} decays collected between 1999 and 2002 with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. We study events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B° or {bar B}° from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2[beta], is derived from the decay-time distributions in such events. We measure sin2[beta] = 0.741 ± 0.067 (stat) ± 0.033 (syst) and.

Book First Measurement of the CP Violating Asymmetries with BaBar

Download or read book First Measurement of the CP Violating Asymmetries with BaBar written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on a preliminary measurement of time-dependent CP-violating asymmetries in B° → J/[psi] K{sub s}° and B° → [psi](2S) K{sub s}° decays recorded by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The data sample consisted of 9.0 fb−1 collected at the [Upsilon](4S) resonance and 0.8 fb−1 off-resonance. One of the pair of neutral B mesons produced at the [Upsilon](4S) was fully reconstructed, while the flavor of the other neutral B meson was tagged at the time of its decay. The value of the asymmetry amplitude, sin2[beta], was determined from a maximum likelihood fit to the time distribution of 120 tagged candidates to be sin2[beta] = 0.12 ± 0.37(stat.) ± 0.09(syst.) (preliminary).

Book MEASUREMENT OF TIME DEPENDENT CP ASYMMETRIES AND CONSTRAINTS ON SIN 2  beta     gamma  WITH PARTIAL RECONSTRUCTION OF B sup 0      D  sup      pi  sup      DECAYS

Download or read book MEASUREMENT OF TIME DEPENDENT CP ASYMMETRIES AND CONSTRAINTS ON SIN 2 beta gamma WITH PARTIAL RECONSTRUCTION OF B sup 0 D sup pi sup DECAYS written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a preliminary measurement of the time-dependent CP-violating asymmetry in decays of neutral B mesons to the final states D*[sup [-+]][pi][sup [+-]], using approximately 178 million B[bar B] events recorded by the BABAR experiment at the PEP-II d[sup +]e[sup -] storage ring. Events containing these decays are selected with a partial reconstruction technique, in which only the high-momentum [pi][sup [+-]] from the B decay and the low-momentum [pi][sup [-+]]. from the D*[sup [-+]]. decay are used. They measure the amplitude of the asymmetry to be -0.041 [+-] 0.016 (stat.) [+-] 0.010 (syst.) and determine bounds on sin(2[beta]+[gamma]).

Book Polarization and CP Violation Measurements

Download or read book Polarization and CP Violation Measurements written by Michael Prim and published by Springer Science & Business Media. This book was released on 2014-03-28 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the thorough analysis of the rare B meson decay into φ K* on data taken by the Belle Collaboration at the B-meson-factory KEKB over 10 years. This reaction is very interesting, because it in principle allows the observation of CP-violation effects. In the Standard Model however, no CP violation in this reaction is expected. An observation of CP asymmetries thus immediately implies new physics. This thesis presents an amplitude analysis of this decay and the search for CP violation in detail and discusses methods to solve related problems: The quantification of multivariate dependence and the improvement of numeric evaluation speed of normalization integrals in amplitude analysis. In addition it provides an overview of the theory, experimental setup, (blind) statistical data analysis and estimation of systematic uncertainties.

Book Improved Measurement of CP Asymmetries in B0 to  ccbar K0    Decays

Download or read book Improved Measurement of CP Asymmetries in B0 to ccbar K0 Decays written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present results on time-dependent CP asymmetries in neutral B decays to several CP eigenstates. The measurements use a data sample of about 227 x 106 [Upsilon](4S) → B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The amplitude of the CP asymmetry, sin2[beta] in the Standard Model, is derived from decay-time distributions from events in which one neutral B meson is fully reconstructed in a final state containing a charmonium meson and the other B meson is determined to be either a B° or {bar B}° from its decay products. We measure sin2[beta] = 0.722 ± 0.040(stat) ± 0.023(syst) in agreement with the Standard Model expectation.

Book Measurement of CP Violating Asymmetries in B0 Decays to CP Eigenstates

Download or read book Measurement of CP Violating Asymmetries in B0 Decays to CP Eigenstates written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23 million [Upsilon](4S) → B{bar B} decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events where one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2[beta], is derived from the decay time distributions in such events. The result is sin2[beta] = 0.34 ± 0.20 (stat) ± 0.05 (syst).

Book Measurement of CP Violating Asymmetry Sin2beta with the BABAR Detector

Download or read book Measurement of CP Violating Asymmetry Sin2beta with the BABAR Detector written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model of electroweak interactions describes CP violation in weak interactions as a consequence of a complex phase in the three-generation Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix. In this framework, measurements of CP-violating asymmetries in the time distribution of neutral B decays to charmonium final states provide a direct measurement of sin2[beta][2], where[beta][triple-bond] arg[-V[sub cd]V*[sub cb]/V[sub td]V*[sub tb]]. The authors report an updated measurement of time-dependent CP-asymmetries in samples of fully reconstructed B decays to charmonium-containing CP eigenstates (b[yields] c[bar c]s). The data for these studies were recorded at the[Upsilon](4S) resonance with the BABAR detector at the PEP-II asymmetric-energy e[sup+]e[sup -] collider at the Stanford Linear Accelerator Center.

Book Amplitude Analysis and Measurement of the Time dependent CP Asymmetry of B0 to KsKsKs Decays

Download or read book Amplitude Analysis and Measurement of the Time dependent CP Asymmetry of B0 to KsKsKs Decays written by and published by . This book was released on 2012 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the first results on the Dalitz-plot structure and improved measurements of the time-dependent CP-violation parameters of the process B° → K{sub S}°K{sub S}°K{sub S}° obtained using 468 x 106 B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy B factory at SLAC. The Dalitz-plot structure is probed by a time-integrated amplitude analysis that does not distinguish between B° and {bar B}° decays. We measure the total inclusive branching fraction?(B° → K{sub S}°K{sub S}°K{sub S}°) = (6.19 ± 0.48 ± 0.15 ± 0.12) x 10−6, where the first uncertainty is statistical, the second is systematic, and the third represents the Dalitz-plot signal model dependence. We also observe evidence for the intermediate resonant states f0(980), f0(1710), and f2(2010). Their respective product branching fractions are measured to be (2.70{sub -1.19}{sup +1.25} ± 0.36 ± 1.17) x 10−6, (0.50{sub -0.24}{sup +0.46} ± 0.04 ± 0.10) x 10−6, and (0.54{sub -0.20}{sup +0.21} ± 0.03 ± 0.52) x 10−6. Additionally, we determine the mixing-induced CP-violation parameters to be S = -0.94{sub -0.21}{sup +0.24} ± 0.06 and C = -0.17 ± 0.18 ± 0.04, where the first uncertainty is statistical and the second is systematic. These values are in agreement with the standard model expectation.

Book A Measurement of the CP Parameter Sine Two Beta Using Fully Reconstructed B to Ccbar Decays at the BABAR Experiment

Download or read book A Measurement of the CP Parameter Sine Two Beta Using Fully Reconstructed B to Ccbar Decays at the BABAR Experiment written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents a measurement of the time-dependent CP-violating asymmetries in the neutral B-meson system performed with data collected with the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data sample used consists of 29.7 fb[sup -1] collected at the[Upsilon](4S) resonance and 3.9 fb[sup -1] collected off-resonance. We analyze three samples of fully-reconstructed B-meson decays: a sample of decays to CP eigenstates in the modes J/[psi] K[sub s][sup 0], [psi](2S) K[sub s][sup 0], [chi][sub cl] K[sub s][sup 0], and J/[psi] K*[sup 0] (822 events); as well as both charged (14304 events) and neutral (10457 events) B decays to flavor-eigenstates including D[sup (*)] and[pi]/[rho]/[alpha][sub 1]. In all cases, the proper decay time difference between the reconstructed B-meson and the recoiling B-meson is determined by measuring the separation of the two decay vertices. Furthermore, the flavor of the recoiling B-meson is tagged using a neural network algorithm. We use the flavor-eigenstate samples to calibrate both the vertexing and tagging performance. We measure the amplitude of the CP asymmetry, sin2[beta]= 0.61[+-] 0.14(stat)[+-] 0.06(syst). These results indicate the existence of indirect CP violation in the B-meson system.

Book Measurement of the CP Asymmetry Parameter Sin 2 beta  at CDF

Download or read book Measurement of the CP Asymmetry Parameter Sin 2 beta at CDF written by and published by . This book was released on 1998 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a measurement of the time-dependent asymmetry in the rate for {bar B}{sub d}° versus B{sub d}° decays to J/[psi]K{sub S}°. In the context of the Standard Model this is interpreted as a measurement of the CP-violation parameter sin(2[beta]). A total of 198 ± 17 B{sub d}°/{bar B}{sub d}° decays were observed in p{bar p} collisions at √s = 1.8 TeV by the CDF detector at the Fermilab Tevatron. The initial b-flavor is determined by a same side flavor tagging technique. Our analysis results in sin(2[beta]) = 1.8 ± 1.1(stat) ± 0.3(syst).

Book Observation of CP Violation in the B sup 0  Meson System

Download or read book Observation of CP Violation in the B sup 0 Meson System written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of[Upsilon](4S) decays collected in 2001, bringing the data available to 32 million B[bar B] pairs. We select events in which one neutral B meson is fully reconstructed in final state containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2[beta], is derived from the decay time distributions in such events. The result sin2[beta]= 0.59[+-] 0.14 (stat)[+-] 0.05 (syst) establishes CP violation in the B[sup 0] meson system. We also determine[lambda]= 0.93[+-] 0.09 (stat)[+-] 0.03 (syst), consistent with no direct CP violation.

Book First CP Violation Results from BABAR

Download or read book First CP Violation Results from BABAR written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present a preliminary measurement of time-dependent CP-violating asymmetries in B[sup 0][yields] J/[psi]K[sub s][sup 0] and B[sup 0][yields][psi](2S)K[sub s][sup 0] decay recorded by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. The data sample consists of 9.0 fb[sup -1] collected at the[Upsilon](4S) resonance and 0.8 fb[sup -1] off-resonance. One of the neutral B mesons, produced in pairs at the[Upsilon](4S), is fully reconstructed. The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. The time difference between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities and the time resolution function are measured with samples of fully-reconstructed semileptonic and hadronic neutral B final states. The value of the asymmetry amplitude, sin2[beta], is determined from a maximum likelihood fit to the time distribution of 120 tagged B[sup 0][yields] J/[psi]K[sub s][sup 0] and B[sup 0][yields][psi](2S)K[sub s][sup 0] candidates: sin2[beta]= 0.12[+-] 0.37 (stat)[+-] 0.09 (syst).

Book A Study of Factorization and a Measurement of CP Violation

Download or read book A Study of Factorization and a Measurement of CP Violation written by Bryan Dahmes and published by . This book was released on 2006 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: Furthermore, we present the results on the time-dependent CP asymmetry in neutral B meson decays to the CP eigenstate J/psiKL. The measurements use a data sample of about 88 million Upsilon(4S) & rarr; BB & d1; decays collected between 1999 and 2002 with the BABAR detector. We study events in which one neutral B meson is fully reconstructed in the J/psiKL final state and the other B meson is determined to be either a B0 or a B & d1;0 from its decay products. The amplitude of the CP asymmetry, which in the Standard Model is proportional to sin 2beta, is derived from the decay-time distributions in such events. We measure sin 2beta = 0.723 +/- 0.158(stat.)+/-0.086(syst.), which is consistent with Standard Model expectations.

Book Measurement of the CP Violating Phase   boldsymbol  sin 2 beta  s     Using   boldsymbol B   0   s  rightarrow J  psi phi   Decays at CDF

Download or read book Measurement of the CP Violating Phase boldsymbol sin 2 beta s Using boldsymbol B 0 s rightarrow J psi phi Decays at CDF written by and published by . This book was released on 2010 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: A B0 s meson can oscillate into its anti-particle, the $ar{B}$0 s meson, before decaying. CP violation in this system is made possible by the presence of amplitudes from both mixed and unmixed B0 s meson decays. The CP violating phase ?s appears in the interference between the decay amplitudes. The quantity sin(2?s) is expected to be small in the standard model. Thus, measuring a large value for sin(2?s) would be an unequivocal sign of new physics participation in the B0 s mixing loop diagram. In this thesis, we present a latest measurement of sin(2?s), using 5.2 fb-1 of data collected at CDF from p$ar{p}$ collisions at a center of mass energy of √s=1.96 TeV. A time-dependent angular analysis, with the production flavor of the B0 s meson identified with flavor tagging methods, is used to extract sin(2?s) from 6̃500 B0 s→ J/?? decays. Other parameters of interest, such as the B0 s lifetime and the decay width difference between the heavy and light B0 s mass eigenstates are determined to high precision. Also, the effect of potential contributions to the final state from B0 s → J/?f0 and B0 s→ J/?K+K- decays is considered for the first time. We present 68% and 95% confidence regions in the ?s plane. The probability that the observed central value is a fluctuation of the data from the standard model expected value of ?s is calculated to be 44%. The observed confidence region shows better agreement with the standard model prediction than previous measurements.

Book Improved Measurements of CP Violating AsymmetryAmplitudes in B0 to Pi pi  Decays

Download or read book Improved Measurements of CP Violating AsymmetryAmplitudes in B0 to Pi pi Decays written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors present updated measurements of the CP-violating parameters S{sub??} and C{sub??} in B° →??− decays. Using a sample of 227 million?(4S) → B{bar B} decays collected with the BABAR detector at the PEP-II asymmetric-energy e+e− collider at SLAC, they observe 467 ± 33 signal decays and measure S{sub {pi}{pi}} = -0.30 ± 0.17(stat) ± 0.03(syst), and C{sub {pi}{pi}} = -0.09 ± 0.15(stat) ± 0.04(syst).