Download or read book Search for Lepton Flavor Violation in the Decays Tau e Gamma and Tau mu Gamma written by and published by . This book was released on 2010 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searches for lepton-flavor-violating decays of a [tau] lepton to a lighter mass lepton and a photon have been performed with the entire dataset of (963 ± 7) x 106 [tau] decays collected by the BABAR detector near the [Upsilon](4S), [Upsilon](3S) and [Upsilon](2S) resonances. The searches yield no evidence of signals and they set upper limits on the branching fractions of [Beta]([tau]{sup {+-}} 2!e{sup {+-}}[gamma])
Download or read book Search for Lepton Flavor Violation in the Decay Tau to Mu Gamma written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Searches for Lepton Flavor Violation in the Decays Tau E Gamma and Tau Mu Gamma written by and published by . This book was released on 2010 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searches for lepton-flavor-violating decays of a? lepton to a lighter mass lepton and a photon have been performed with the entire dataset of (963 ± 7) x 106? decays collected by the BABAR detector near the?(4S),?(3S) and?(2S) resonances. The searches yield no evidence of signals and they set upper limits on the branching fractions of?(?{sup {+-}} → e{sup {+-}}?)
Download or read book A Search for Lepton Flavor Violation in Tau Decays at BABAR written by O. Igonkina 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 recent BABAR search for lepton flavor violation in tau decays. The search for {tau} {yields} {ell}{ell}{ell} ({ell} = e, {mu}) decays is based on a data sample of 91.6 fb{sup -1}. No signal is found in any of six channels and 90% CL upper limits are set in the range of (1-3) x 10{sup -7}. The search for {tau} {yields} {mu}{gamma} decay is done with a 63 fb{sup -1} data sample. The number of observed events is consistent with expected background level and a preliminary upper limit is set at 2 x 10{sup -6} at 90% CL.
Download or read book Search for Lepton Flavour Violation in the Decay Tau to Mu Gamma written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for Lepton Flavour Violation in the Decay Tau to Mu Gamma written by M. Roney and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the lepton flavour violating decay {tau}{sup {+-}} {yields} {mu}{sup {+-}}{gamma} has been performed using 221.4 fb{sup -1} of data collected at an e{sup +}e{sup -} centre-of-mass energy of 10.58 GeV with the BABAR detector at the PEP-II storage ring. The search has an efficiency of 7.45 {+-} 0.65% for an expected background level of 6.2 {+-} 0.5 events. In the final sample 4 candidate events are selected. As there is no evidence for a signal in this data, for this preliminary result we set an upper limit of {Beta}({tau}{sup {+-}} {yields} {mu}{sup {+-}}{gamma})
Download or read book Lepton Flavor Violation in Tau Decays at BABAR written by Swagato Banerjee and published by . This book was released on 2006 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Searches for lepton flavor violating tau {yields} l gamma, tau {yields} lhh decays at the BABAR experiment are presented. Upper limits on the branching ratios are obtained at the level of O(10{sup -7}) at 90% confidence level.
Download or read book Charakterisierung von Schleifscheibentopographien aus fertigungstechnischer Sicht written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search For the Lepton Flavor Violating Decays Y 3S e Tau and Y 3S mu Tau written by and published by . This book was released on 2008 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Charged lepton-flavor violating processes are extremely rare in the Standard Model, but they are predicted to occur in several beyond-the-Standard Model theories, including Supersymmetry or models with leptoquarks or compositeness. We present a search for such processes in a sample of 117 x 106 [Upsilon](3S) decays recorded with the BABAR detector. We place upper limits on the branching fractions BF([Upsilon](3S) 2!e{sup {+-}}[tau]{sup {-+}})
Download or read book Search for Neutrinoless Tau Decays written by and published by . This book was released on 2003 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the lepton family number violating decays [tau] 2!e[gamma] and [tau] 2![mu][gamma] has been performed using CLEO-II data. No evidence of a signal has been found and the corresponding upper limits are B([tau] 2!e[gamma])
Download or read book Search for the Lepton Flavour Violating Decay Tau e Gamma written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search is done on the entire BaBar data set for the neutrino-less tau decay tau->e gamma. No evidence for the decay is found and a 90% confidence level upper limit is determined to be 3.3 * 10^( -8) including systematic uncertainty. This measurement is a factor of three improvement from the previous best result from BaBar.
Download or read book Search for the Lepton Flavour Violating Decay Tau e Gamma written by Clayton Daniel Lindsay and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search is done on the entire BaBar data set for the neutrino-less tau decay tau->e gamma. No evidence for the decay is found and a 90% confidence level upper limit is determined to be 3.3 * 10^( -8) including systematic uncertainty. This measurement is a factor of three improvement from the previous best result from BaBar.
Download or read book Search for Lepton Flavor Violation in Tau to Ell Ell Ell written by and published by . This book was released on 2003 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the lepton-flavor-violating decay of the tau into three charged leptons has been performed using 91.5 fb−1 of data collected at an ee− center-of-mass energy of 10.58 GeV with the BABAR detector at the PEP-II storage ring. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1-3) x 10−7 at 90% confidence level.
Download or read book Lepton Flavor Violation written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The connection of rare decays to supersymmetric grand unification is highlighted, and a review of the status of rare decay experiments is given. Plans for future investigations of processes that violate lepton flavor are discussed. A new result from the MEGA experiment, a search for [mu][sup +] [yields] e[sup +] [gamma], is reported to be B.R.
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.
Download or read book Search for Lepton Flavor Violation in the Decay L sup H sup h written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the lepton-flavor-violating decay of the tau into one charged lepton and two charged hadrons has been performed using 221.4 fb−1 of data collected at an ee− center-of-mass energy around 10.58 GeV with the BABAR detector at the PEP-II storage ring. In all 14 decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (0.7-4.8) x 10−7 at 90% confidence level. All results are preliminary.
Download or read book Search for Lepton Flavor Violating Decays Tau to L omega l written by and published by . This book was released on 2007 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for lepton flavor violating decays of a [tau] to a lighter-mass charged lepton and an [omega] vector meson is performed using 384.1 fb−1 of ee− annihilation data collected with the BABAR detector at the Stanford Linear Accelerator Center PEP-II storage ring. No signal is found, and the upper limits on the branching ratios are determined to be [beta]([tau]{sup {+-}} 2!e{sup {+-}}[omega])
