Download or read book Rare and Forbidden Decays of the Tau Lepton written by Igor Volobouev and published by . This book was released on 1997 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Search for the Rare and Forbidden Decays D0 2 V L L written by and published by . This book was released on 2003 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: I report the results of a search for flavor-changing neutral current, leptonflavor, and lepton-number violating decays of the 3 and 4-body decay modes of the D0 (and its antiparticle) containing muons and electrons. Using data from Fermilab charm hadroproduction experiment E791, I examine modes with two leptons and either a [rho]0, $\bar{K}$0, or [Phi] vector meson or a non-resonant [pi][pi], K[pi], or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, branching-fraction upper limits, typically at the 10-4 level, are presented at the 90% confidence level for the 27 decay modes examined. Of these searches, 18 are investigations of decays without previous published results; several others have significantly improved sensitivity over previous results.
Download or read book Rare Leptonic Decays of the D Meson and Tau Lepton written by Ilya Narsky and published by . This book was released on 2001 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Search for Rare Multi Pion Decays of the Tau Lepton Using the BABAR Detector written by and published by . This book was released on 2007 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for the decay of the [tau] lepton to rare multi-pion final states is performed using the BABAR detector at the PEP-II asymmetric-energy e+e- collider. The analysis uses 232 fb-1 of data at center-of-mass energies on or near the [Upsilon](4S) resonance. In the search for the [tau]- 2!3[pi]-2[pi]+2[pi]°[nu]{sub [tau]} decay, we observe 10 events with an expected background of 6.5{sup +2.0}{sub -1.4} events. In the absence of a signal, we calculate the decay branching ratio upper limit [beta]([tau]- 2!3[pi]-2[pi]+2[pi]°[nu]{sub [tau]})
Download or read book A Search for the Rare and Forbidden Decays D0 u2192 V L L written by and published by . This book was released on 2003 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: I report the results of a search for flavor-changing neutral current, leptonflavor, and lepton-number violating decays of the 3 and 4-body decay modes of the D0 (and its antiparticle) containing muons and electrons. Using data from Fermilab charm hadroproduction experiment E791, I examine modes with two leptons and either a ?0, $\bar{K}$0, or ? vector meson or a non-resonant ?? , K? , or KK pair of pseudoscalar mesons. No evidence for any of these decays is found. Therefore, branching-fraction upper limits, typically at the 10-4 level, are presented at the 90% confidence level for the 27 decay modes examined. Of these searches, 18 are investigations of decays without previous published results; several others have significantly improved sensitivity over previous results.
Download or read book Strange Decays of the Tau Lepton written by and published by . This book was released on 1992 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of hadronic [tau] decays to states containing at least one strange meson are reviewed. New results are presented from a self-consistent analysis of one-prong decays including kaons and from a study of the kaon content in three-prong decays. First observations of the resonance contribution to the strange axial-vector channel are reported. The findings are compared to model predictions of K[sub 1] mixing and interference in [tau] decay.
Download or read book Search for Rare Multi pion Decays of the Tau Lepton Using the BABAR Detector written by Ruben Ter-Antonyan and published by . This book was released on 2006 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A search for the decay of the tau lepton to rare multi-pion final states is performed using the BABAR detector at the PEP-II asymmetric-energy ee− collider. The analysis uses 232 fb−1 of data at center-of-mass energies on or near the Upsilon(4S) resonance. In the search for the tau− -> 5pi−2pi2pi0nu[tau] decay, we observe 10 events with an expected background of 6.5+2̇0−1.4 events. In the absence of a signal, we calculate the decay branching ratio upper limit B(tau− -> 5pi−2pi+2pi0nu[tau]) 3.4x10−6 at 90% confidence level. This is more than a factor of 30 improvement over the previously established limit. In addition, we search for the exclusive decay mode tau− - 2omega.pi−nu[tau] with the further decay of omega -> pi−pi+pi0. We observe 1 event, expecting 0.4+1̇0−0.4 background events, and calculate the upper limit B(tau− -> 2omega.pi−nu[tau])
Download or read book Search for Rare and Forbidden Decays of D0 l l written by C. Chen and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on a search for the flavor-changing neutral current decays D{sup 0} {yields} e{sup +}e{sup -} and D{sup 0} {yields} {mu}{sup +}{mu}{sup -}, and the lepton-flavor violating decay D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}}. The measurement is based on 122fb{sup -1} of data collected by the BABAR detector at the PEP-II asymmetric e{sup +}e{sup -} collider. No evidence is found for any of the decays. The upper limits on the branching fractions, at the 90% confidence level, are 1.2 x 10{sup -6} for D{sup 0} {yields} e{sup +}e{sup -}, 1.3 x 10{sup -6} for D{sup 0} {yields} {mu}{sup +}{mu}{sup -}, and 8.1 x 10{sup -7} for D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}}.
Download or read book Reflections on Experimental Science written by Martin L. Perl and published by World Scientific. This book was released on 1996 with total page 551 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is a collection of important lecture and original articles and commentaries by Martin Perl, discoverer of the tau lepton and the third generation of elementary particles, and this year''s Nobel Prize winner. This book contains a fascinating and realistic picture of experimental science based on the high energy physics research work carried out by him. Using reprints of his articles with his commentaries, the author presents the various aspects of experimental research in science: the pleasures and risks of experimental work; the pain and frustration with experiments that are useless or fail; the dreaming about experiments that were not carried out; the constant search for innovation and creativity in the work; and the special joy of discovery. The articles and commentaries range from the early days of bubble chambers and spark chambers in the 1950''s to the author''s present research, experiments at an electron-positron collider and a search for free quarks. The book is for the general reader as well as the scientist.
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 Physics with Tau Leptons written by Achim Stahl and published by Springer. This book was released on 1999-11-22 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book reviews the current status of tau physics. It addresses the properties of the tau lepton and summarizes results achieved with tau leptons in the fields of precision tests of the Standard Model, investigations of the strong interaction and many searches for new physics beyond the scope of the Standard Model.
Download or read book Search for the Rare Leptonic Decay B Tau Nubar 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 a search for the decay B[sup -] [yields] [tau][sup -] [bar [nu]][sub [tau]] in a sample of 88.9 x 10[sup 6] B[bar B]pairs recorded with the BABAR detector at the SLAC B-Factory. One of the two B mesons from the [Upsilon](4S) is reconstructed in a hadronic or a semileptonic final state and the decay products of the other B in the event are analyzed for consistency with a B[sup -] [yields] [tau][sup -] [bar [nu]][sub [tau]] decay. We find no evidence of a signal and set an upper limit on the branching fraction of [Beta](B[sup -] [yields] [tau][sup -] [bar [nu]][sub [tau]])
Download or read book Decays of the Tau Lepton written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous measurements of the branching fractions of the tau lepton result in a discrepancy between the inclusive branching fraction and the sum of the exclusive branching fractions to final states containing one charged particle. The sum of the exclusive branching fractions is significantly smaller than the inclusive branching fraction. In this analysis, the branching fractions for all the major decay modes are measured simultaneously with the sum of the branching fractions constrained to be one. The branching fractions are measured using an unbiased sample of tau decays, with little background, selected from 207 pb−1 of data accumulated with the Mark II detector at the PEP ee− storage ring. The sample is selected using the decay products of one member of the .gamma.gamma.− pair produced in e+e− annihilation to identify the event and then including the opposite member of the pair in the sample. The sample is divided into subgroups according to charged and neutral particle multiplicity, and charged particle identification. The branching fractions are simultaneously measured using an unfold technique and a maximum likelihood fit. The results of this analysis indicate that the discrepancy found in previous experiments is possibly due to two sources. First, the leptonic branching fractions measured in this analysis are about one standard deviation higher than the world average. The measured leptonic branching fractions correspond to a tau lifetime of (3.0 +- 0.2) x 10−13 s. Secondly, the total branching fraction to one charged hadron plus at least one neutral particle is measured to be (7 +- 3)% higher than the branching fraction expected from a combination of previous measurements and theoretical predictions. It is shown that decay modes involving the eta are not expected to contribute more than 3% to this excess.
Download or read book TAU written by and published by . This book was released on 1997 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particle Physics at the Year of Astronomy written by A. I. Studenikin and published by World Scientific. This book was released on 2011 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: These proceedings are devoted to a wide variety of both theoretical and experimental areas in particle physics. The topics include physics at accelerators and studies of Standard Model and Beyond, neutrino and astroparticle physics, cosmology, CP Violation and rare decays, hadron physics, and new developments in quantum field theory. The papers of the volume reveal the present status and new development in the above mentioned items. In particular, the first results on measurement of LHC pp collision events are also reported.
Download or read book Third Workshop on the Tau Charm Factory written by Jasper Kirkby and published by Atlantica Séguier Frontières. This book was released on 1994 with total page 870 pages. Available in PDF, EPUB and Kindle. Book excerpt:
