Download or read book CKM Parameters and Rare B Decays written by and published by . This book was released on 2005 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1994 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.
Download or read book Inclusive Rare B Decays Using Effective Field Theories written by Christian Bauer and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this thesis we will discuss several properties of rare decays of ' B' mesons. First we discuss properties of the inclusive radiative decay 'B¢' [right arrow] 'Xs'ã, where 'Xs' stands for any hadronic state containing an 's' quark. We extend previous studies of this decay, which included perturbative corrections to order Ã's' and nonperturbative contributions up to order ([Lambda]QCD/' mb')2 and calculate the O ([Lambda]QCD/'mb')3 contributions to this decay. The values of the nonperturbative parameters entering at this order are unknown, leading to uncertainties in the standard model prediction of this decay. We estimate the size of these nonperturbative uncertainties by varying these parameters in the range suggested by dimensional analysis. We also estimate uncertainties arising from a cut on the photon energy which is required experimentally. Another decay mode investigated is 'B¢' [right arrow] ' Xs'3⁄4+3⁄4-. We study the O ([Lambda]QCD/'mb')3 contributions to the leptonic invariant mass spectrum, the forward-backward asymmetry and hadronic invariant mass moments and estimate the resulting uncertainties. We calculate how the size of these uncertainties depend on the value of an experimental cut that has to be applied to eliminate the large background from other 'B' decays. A model independent way to determinate the CKM matrix element @' Vub'@ from the dilepton invariant mass spectrum of the inclusive decay B[right arrow]Xu3⁄4+ n is presented next. We show that cuts required to eliminate the charm background still allow for a theoretically clean way to determine the CKM matrix element @'Vub'@. We also discuss the utility of the 'B¢' [right arrow] 'Xs'3⁄4 +3⁄4- decay rate above the y (2'S') resonance to reduce the resulting uncertainties. Finally, we introduce a novel effective theory valid for highly energetic particles. In decays where the phase space is sufficiently restricted such that final state particles have very high energies compared to their mass, the perturbative as well as nonperturbative series diverge. The effective theory presented allows to sum perturbative Sudakov logarithms in a framework that also incorporates the nonperturbative physics in such limits of phase space.
Download or read book B Decays written by Sheldon Stone and published by World Scientific. This book was released on 1994 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt: This 2nd edition is an extensive update of "B Decays?. The revisions are necessary because of the extensive amount of new data and new theoretical ideas. This book reviews what is known about b-quark decays and also looks at what can be learned in the future.The importance of this research area is increasing, as evidenced by the approval of the luminosity upgrade for CESR and the asymmetric B factories at SLAC and KEK, and the possibility of experiments at hadron colliders.The key experimental observations made thus far, measurement of the lifetimes of the different B species, B0-B0 mixing, the discovery of ?Penguin? mediated decays, and the extraction of the CKM matrix elements Vub and Vcb from semileptonic decays, as well as more mundane results, are described in great detail by the experimentalists who have been closely involved with making the measurements. Theoretical progress in understanding b-quark decays using HQET and lattice gauge techniques are described by theorists who have developed and used these techniques.Synthesizing the experimental and theoretical information, several articles discuss the implications for the ?Standard Model? and how further tests can be done using measurements of CP violation in the B system.
Download or read book Exclusive Rare B Decays to Two Light Pseudoscalar Mesons written by Petr Borisovich Gaidarev and published by . This book was released on 1997 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Present Status of Inclusive Rare B Decays written by and published by . This book was released on 2003 with total page 79 pages. Available in PDF, EPUB and Kindle. Book excerpt: We give a status report on inclusive rare B decays, highlighting recent developments and open problems. We focus on the decay modes B → X{sub s, d}?, B → X{sub s}ll− and B → X{sub s}?{bar?}and on their role in the search for new physics. Most of the inclusive rare B decays are important modes of flavour physics due to the small hadronic uncertainties. They can be regarded as laboratories to search for new physics. We collect the experimental data already available from CLEO and the B factories BABAR and BELLE. We review the NLL and NNLL QCD calculations of the inclusive decay rates that were recently completed, and discuss future prospects, especially the issue of the charm mass scheme ambiguity. Finally, we analyze the phenomenological impact of these decay modes, in particular on the CKM phenomenology and on the indirect search for supersymmetry. We also briefly discuss direct CP violation in inclusive rare B decays, as well as the rare kaon decays K+ →?+?{bar {nu}} and K{sub L} →?° {nu}{bar {nu}}, which offer complementary theoretically clean information.
Download or read book B Physics And Cp Violation Bcp4 Proceedings Of The International Workshop written by T Ohshima and published by World Scientific. This book was released on 2001-09-25 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book offers the first strong evidence of the existence of CP violation in neutral B decays extracted from sophisticated B factories in the US and Japan. It also holds out the expectation of rare B decays and D, K physics in the near future. In addition, new physics beyond the Standard Model is described. Both experimental and theoretical points of view are given.
Download or read book Search for Exclusive Rare Baryonic Decays of B Mesons written by Curtis William Ward and published by . This book was released on 1998 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book B Physics Physics Beyond The Standard Model At The B Factory Proceedings Of The 1994 International Workshop written by S Suzuki and published by World Scientific. This book was released on 1995-07-14 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume reviews the recent progress of B physics, and discusses theoretical and experimental aspects of the physics which will be explored at the B factory. CP violation and new physics beyond the Standard Model are the main issues of the discussion.
Download or read book Beyond The Standard Model Iii written by S Godfrey and published by World Scientific. This book was released on 1993-06-25 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a critical review of the standard model and the prospects for discovering new physics. It also discusses the recent developments that have taken place in new physics theories beyond the standard model.
Download or read book Suppressed Charmed B Decay written by and published by . This book was released on 2009 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- [eta][pi]+ decays in approximately 230 million [Upsilon](4S) → B$\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a0+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle [gamma], one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle [gamma] can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle [gamma] and, in comparison to the current decays that are being employed, could significantly enhance the measurement of this angle. However, the low expected branching fraction for the B0 → D*- a0+ decay channels could severely impact the measurement. A prerequisite of the measurement of the CKM angle is the observation of the B0 → D*- a0+ decay on which this thesis reports. The BABAR experiment consists of the BABAR detector and the PEP-II e+e- collider. The design of the experiment has been optimized for the study of CP violation in the decays of neutral B mesons but is also highly suitable for the search for rare B decays such as the B0 → D*- a0+ decay. The PEP-II collider operates at the [Upsilon](4S) resonance and is a clean source of B$\bar{B}$ meson pairs.
Download or read book RARE DECAYS INCLUDING PENGUINS 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 exclusive charmless semileptonic B decays, B [yields] [rho][ell][nu], and the extraction of the CKM parameters V[sub ub]. IN a data sample of 55 x 10[sup 6] B[bar B] events they measure a branching fraction of [Beta](B [yields] [rho][ell][nu]) = (3.39 [+-] 0.44[sub stat] [+-] 0.52[sub sys] [+-] 0.60[sub th]) x 10[sup -4] yielding V[sub ub] = (3.69 [+-] 0.23[sub stat] [+-] 0.27[sub sys -0.59th][sup +0.40]) x 10[sup -3]. Next, they report on a preliminary study of the radiative penguin modes B [yields] K[ell][sup +][ell][sup -] and B [yields] K*[ell][sup +][ell][sup -]. In a data sample of 84 x 10[sup 6] B[bar B] events they observe a significant signal (4.4[sigma]) in B [yields] K[ell][sup +][ell][sup -], yielding a branching fraction of [Beta](B [yields] K[ell][sup +][ell][sup -]) = (0.78[sub -0.20-0.18][sup +0.24+0.11]) x 10[sup -6]. In B [yields] K*[ell][sup +][ell][sup -] the observed yield is not yet significant (2.8[sigma]), yielding an upper limit of the branching fraction of [Beta](B [yields] K*[ell][sup +][ell][sup -]) 3.0 x 10[sup -6] [at] 90% confidence level. Finally, they summarize preliminary results of searches for B [yields] [rho]([omega])[gamma], B[sup +] [yields] K[sup +] [nu][bar [nu]] and B[sup 0] [yields] [ell][sup +][ell][sup -].
Download or read book On Exclusive and Inclusive Rare B Decays written by and published by . This book was released on 2003 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report recent results in rare B decays. Our focus will be on b 2!d[gamma] and b 2!sll− transitions. We discuss their impact on the CKM phenomenology and their role within our search for new physics. In particular, we analyze the impact of a recent lattice QCD estimate of the B 2!K* form factor at zero recoil. We also briefly discuss the presently available optimal theoretical tools for the inclusive and exclusive modes.
Download or read book Observation of CP Violation in B DK Decays written by Paolo Gandini and published by Springer Science & Business Media. This book was released on 2013-09-05 with total page 179 pages. Available in PDF, EPUB and Kindle. Book excerpt: CP violation is a well-established phenomenon in particle physics, but until 2001 it was only observed in kaons. In the last decade, several matter-antimatter asymmetries have been observed in neutral B mesons in line with the expectations of the Standard Model of the weak interaction. Direct CP violation is also expected in the decay rates of charged B+ mesons versus that of B- mesons, though the greatest effects are present in a decay that occurs just twice in 10 million decays. Such rarity requires huge samples to study and this is exactly what the LHC, and its dedicated B-physics experiment LHCb provide. This thesis presents an analysis of the first two years of LHCb data. The author describes the first observation of the rare decay, B- → DK-, D → π-K+ and the first observation of direct CP violation in this B decay. The work constitutes essential information on the experiment’s measurement of a fundamental parameter of the theory and stands as a benchmark against which subsequent analyses of this type will be compared.
Download or read book Lepton And Photon Interactions At High Energies Proceedings Of The Xxii International Symposium written by Richard Brenner and published by World Scientific. This book was released on 2006-01-26 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Lepton-Photon symposiums — as represented by the contributions in this volume — are among the most popular conferences in high energy physics since they give an in-depth snapshots of the status of the field as provided by leading experts.The volume covers the latest results on flavor factories, quantum chromodynamics (QCD), electroweak physics, dark matter searches, neutrino physics and cosmology, from a phenomenological point of view. It also offers a glimpse of the immediate future of the field through summaries on the status of the next generation of high energy accelerators and planned facilities for astroparticle physics.The review nature of the articles makes the volume particularly useful to students, as well as being of interest to established researches in high-energy physics and related fields.
Download or read book Study of Rare B Meson Decays Related to the CKM Angle Beta at BaBar written by and published by . This book was released on 2007 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Symmetry And Spin In Standard Model Proceedings Of The Seventh Lake Louise Winter Institute written by Faqir C Khanna and published by World Scientific. This book was released on 1992-12-09 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: The subject of this Institute is the importance of Spin and Symmetry measurements in probing the Standard Model and QCD, polarization in lepton-quark interactions, nucleon spin structure functions, spin effects in high energy hadronic interactions, and electromagnetic spin physics at medium energies.The pedagogical nature of the invited talks makes this book suitable for senior graduate students and subatomic physicists in general, while the specialist talks make the volume useful to practitioners in the field.
