Download or read book Experimental Test of Lepton Universality in Tau Decay written by and published by . This book was released on 2003 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The branching fractions for [tau] 2!e[nu][nu]{sub {tau}} and h[nu]{sub {tau}} are measured using data collected with the CLEO detector at the CESR ee− collider: [Beta]{sub e} = 0.1776 ± 0.0006 ± 0.0017, [beta][mu] = 0.1737 ± 0.0008 ± 0.0018, and [Beta]{sub h} = 0.1152 ± 0.0005 ± 0.0012, where the first error is statistical, the second systematic, and h refers to either a charged [pi] or K. Also measured is the tau mass, m{sub {tau}} =(1778.2 ± 1.4) MeV. Lepton universality is affirmed by the relative branching fractions ([Beta]{sub {mu}}/[Beta]{sub e} = 0.9777 ± 0.0063 ± 0.0087, [Beta]{sub h}/[Beta]{sub e} = 0.6484 ± 0.0041 ± 0.0060) and the charged-current gauge coupling-constant ratios (g{sub {mu}} = g{sub e} = 1.0026 ± 0.0055, g{sub {tau}}/g{sub {mu}} = 0.9990 ± 0.0098). The tau mass result may be recast as a tau neutrino mass limit, m{sub {nu}{sub {tau}}}

Download or read book A Test of Lepton Universality Using the Tau formula Decay written by Ian Timothy Lawson and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinematic Reconstruction of Tau Leptons and Test for Lepton Universality in Charged Weak Interactions with the CMS Experiment written by Philip Sauerland and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tau Lepton Physics Proceedings Of The Second Workshop written by K K Gan and published by World Scientific. This book was released on 1993-04-08 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt: The II International Workshop on Tau Lepton Physics was held in Ohio, USA in September 1992. Its purpose is to gather the experts on tau lepton physics to examine the current understanding of the tau lepton physics and to assess future prospects. A particular emphasis of the Workshop was a detailed examination of the '1-prong problem': the discrepancy between the inclusive measurement of one-charged-particle decay branching ratio and the sum of the exclusive decays. The Workshop also stimulated new ideas on tests of the Standard Model using the third generation lepton and assessed the future prospects of the lepton physics.

Download or read book Testing Lepton Universality Using One prong Hadronic Tau Decays written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Tau Lepton Identification and Universality Tests with the ATLAS Experiment written by Samuel Dysch and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probing Lepton Flavour Violation Via Neutrinoless tau 2 mu Decays with the ATLAS Detector written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This article presents the sensitivity of the ATLAS experiment to the lepton-flavour-violating decays of [tau]2![mu]. A method utilising the production of [tau] leptons via W2!tau][nu] decays is used. This method is applied to the sample of 20.3 fb-1 of pp collision data at a centre-of-mass energy of 8 TeV collected by the ATLAS experiment at the LHC in 2012. Lastly, no event is observed passing the selection criteria, and the observed (expected) upper limit on the [tau] lepton branching fraction into three muons, Br([tau]2![mu]), is 3.76×10-7 (3.94×10-7) at 90 % confidence level.

Download or read book Test of Lepton Universality in Upsilon 1S Decays at BaBar written by and published by . This book was released on 2010 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ratio R{sub??}(?(1S))=?{sub?(1S)→??−}/?{sub?(1S)→?+?−} is measured using a sample of (121.8 ± 1.2) x 106?(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays?(3S) →?(1S){sub?+{pi}−}, {Upsilon}(1S) → l+l−, where l =?, {tau}. The result, R{sub {tau}?}({Upsilon}(1S))=1.005 ± 0.013(stat) ± 0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

Download or read book Test of Lepton Flavor Universality by the Measurement of the B0 D Branching Fraction Using Three prong tau Decays written by R. Aaij and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Test of Lepton Universality with 0b pK l l Decays written by Roel Aaij and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 16th Conference on Flavor Physics and CP Violation written by Anjan Giri and published by Springer Nature. This book was released on 2019-11-13 with total page 493 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting the proceedings of FPCP 2018, this book reviews the status quo of flavor physics and discusses the latest findings in this exciting area. Flavor physics has been instrumental in the formulation and understanding of the standard model, and it is possible that the direction of new physics will be significantly influenced by flavor sector, also known as the intensity frontier, making it possible to indirectly test the existence of new physics up to a very high scale, beyond that of the energy frontier scale accessible at the LHC. The book is intended for academics around the globe involved in particle physics research, professionals associated with the related technologies and those who are interested in learning about the future of physics and its prospects and directions.

Download or read book Reconstruction of Hadronic Decay Products of Tau Leptons with the ATLAS Experiment written by and published by . This book was released on 2016 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents a new method of reconstructing the individual charged and neutral hadrons in tau decays with the ATLAS detector. The reconstructed hadrons are used to classify the decay mode and to calculate the visible four-momentum of reconstructed tau candidates, significantly improving the resolution with respect to the calibration in the existing tau reconstruction. The performance of the reconstruction algorithm is optimised and evaluated using simulation and validated using samples of Z → [tau][tau] and Z(→ [mu][mu])+jets events selected from proton-proton collisions at a centre-of-mass energy √s = 8 TeV, corresponding to an integrated luminosity of 5 fb-1.

Download or read book Decays of the Tau Lepton written by Patricia Burchat and published by Ann Arbor, Mich. : University Microfilms International. This book was released on 1986 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book TAU written by and published by . This book was released on 1999 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Electroweak Interactions and Unified Theories written by J. Thanh Van Tran and published by Atlantica Séguier Frontières. This book was released on 1988 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Lepton Flavour Violating Decays Tau L Ks with the BABAR Detector written by and published by . This book was released on 2009 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the search for the lepton flavour violating decay [tau] → lK°{sub s} with the BaBar experiment data. This process and many other lepton flavour violating [tau] decays, like [tau] → [mu][gamma] and [tau] → lll, are one of the most promising channel to search for evidence of new physics. According to the Standard Model and the neutrino mixing parameters, branching fractions are estimated well below 10−14, but many models of new physics allow for branching fractions values close to the present experimental sensitivity. This analysis is based on a data sample of 469fb−1 collected by BABAR detector at the PEP-II storage ring from 1999 to 2007, equivalent to 431 millions of [tau] pairs. the BABAR experiment, initially designed for studying CP violation in B mesons, has demonstrated to be one of the most suitable environments for studying [tau] decays. The tracking system, the calorimeter and the particle identification of BABAR, together with the knowledge of the [tau] initial energy, allow an extremely powerful rejection of background events that, for this analysis, is better than 10−9. Being [tau] → lK°{sub s} a decay mode without neutrinos, the signal [tau] decay can be fully reconstructed. Kinematical constraints are used in a fit that provides a decay tree reconstruction with a high resolution. For this analysis MC simulated events play a decisive role for estimating the signal efficiency and study the residual background. High statistics MC sample are produced simulating detector conditions for different periods of data collection, in order to reduce any discrepancies with the data. When discrepancies can not be removed, we perform studies to compute a correction factor or an estimation of systematic errors that need to be included in the final measurement. A significant improvement of the current result can be reached only with a higher statistics and, therefore, with a new collider providing a luminosity from 10 to 100 times more than PEP-II. A new detector, with improved performance and able to collect data in a high background environment, is also requested to fully exploit the capability of such amount of data. In fact, only keeping the efficiency and the background as similar as possible to present ones, we will be able to scale almost linearly the estimated upper limit according to the luminosity. The strong potential of improvement for the search of lepton flavour violation [tau] decays makes the building of such a machine highly desirable.