DOCSLIB.ORG

3 1 9 University of Rochester, Rochester, NY 14627

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
3 1 9 University of Rochester, Rochester, NY 14627 319 NEW PERSPECTIVE ON B SEMILEPTONIC DECAY RATE PROBLEM FROM CLEO Youngjoon Kwon University of Rochester, Rochester, NY 14627 Abstract By studying D-lepton angle correlations, CLEO observed first evidence for has fJ-+DX decay and measured r(fJ -+ fJX)/r(fJ -+ DX) = 0.107 ± 0.029 ± O.Q18. In addition, the D-lepton correlation study enabled us to set an upper limit for inclusive charmless hadronic B decay: B(b -+ 8.5%(@90% CL). These results give us a new under­ sg) < standing of the B semileptonic decay problem. 320 Table 1: Current status of B semileptonic decay problem. b decay Branching Ratio (%) modes bsL = 10.5 ± 0.5 b-+c(u)ev, c(u)µv f>sL 2 (10.5 ± 0.5) x b-+c(u)rv �bsL 2.6 ± 0.1 b-+c(u)ud rud bsL 42.0 ± 2.0 ± 4.2 b-+c(u)c s D, 10.0 ± 2.7 (cc) 3.0 ± 0.5 baryons 1.1 ±0.8 upper vertex 150, D- O?? b-+s(d)g, s(d)qq 1?? [ Total 80.7 ± 4.2 ± 4.2 1 Introduction For several years it has been realized that the B semileptonic decay branching ratio is lower than theoretical expectations. Last year, a CLEO measurement with dilepton events1) removed the substantial model dependence of existing measurements based on single lepton events and confirmed the low value for semileptonic branching ratio. A possible explanation of the low value is that the process b-+ces has a higher rate than expected. That explanation, however, B-+ predicts a higher rate fortotal charm production, B-+DX + DX, than is observed. To gain further understanding, one would like to measure separately the rates for B -+ DX and B -+ DX, rather than measuring only their sum. By studying D-lepton angle correlations, CLEO has carried out these measurements. 2 Motivation Table 1 shows one way to view the current status of B semileptonic decay ratio problem. We list all the separate components of B decays, give their individual branching ratios based ( on measurement and/or theory), and see if they sum to 100%. We express several of the components in terms of bsL, the B semileptonic decay branching ratio, whose measured value1) is (10.49 ± 0.46)%. For the b cti.d'and b uud' we use a QCD calculation by Bagan et -+ -+ . aJ.3), which gives Tud :: r(b -+ cti.d')/r(b -+ cev) = 4.0 ± 0.4 . (1) We take the contribution from b-+cud' , b-+uud' as equaling rudbsL, thereby assuming that 321 the b piece has a multiplier similar to the b --t c piece. --t u We split the b ces contribution into several parts: (a)upper vertex 1 D,; (b) char­ --t monium; (c) baryons from b ces decay; (d) upper vertex D0, n+ . The numbers quoted for --t (a)-(c) are from existing CLEO measurements. For the baryons, we quoted the central value of the measurement in the spirit of making best educated guess, while CLEO does not claim a signal for it. Same thing is true for the estimation of lower vertex D, production. Traditionallythe upper vertex D 2 contributions have been taken aszero without making serious experimental attempt. The contributions from rare decays b s(d)g, s(d)qif. has not --t been experimentally measured, nor its inclusive upper limit has been set. Theorists have estimated it to be from the Standard Model. � 1 % Adding these all up, we come up with (80.7 ± 4.2 ± 4.2) %, which is far less than the desired 100 %. Most experimental uncertainties are in the upper vertex D production and b sg 3 decays. In this paper, we present new results of CLEO experiment on these two --t issues. 3 D-lepton Correlation Technique The CLEO collaboration has developed a meson-lepton correlation technique to measure the inclusive B decay branching ratio to a given meson, separately to particle and antiparticle final states.4) We use this technique to address the issues of both upper vertex D production and b sg decay. The principle underlying the technique is that if one B from a BB pair decays --t semileptonically, with a high momentum lepton, then the other decay products from that B will have substantial angular correlations with the lepton, tending to come off back-to-back to it, while the decay products from the other B have negligible angular correlations with the lepton. The lepton tags the flavor of its parent B, and thus also the other B (with a small correction needed formixin g). Therefore by simultaneously studying the charge combination of lepton and D, and their angular distributions, we can separately measure the inclusive decay branching ratios of B DX (lower vertex) and B DX (upper vertex). --t --t 4 Experimental Procedures and Results We use the BB events of £, 2.41 fb-1 , collected with CLEO II detector. Signal leptons are = required to have momenta between 1.5 and 2.8 GeV /c. D mesons are identified through the For a charm meson produced in B decay, we it an 'upper vertex' charm meson it is produced fromW 1 call if fragmentation, and a 'lower vertex' charm meson if it from a hadronization of the quark produced primarily is c in b-+cW 2 From now on, we will use D to inclusive represent n° and n+, but not D., unless explicitly specified. 3From now on, we denote to generically include and decays b-+sg b-+s(d)g b-+s(d)qq 322 1.00•101 (o) D/1- (b) D/1+ 120000 750000 80000 500000 40000 250000 0 ..... 0 -1.0 -0.5 0.0 0.5 1.0 -1.0 -0.5 0.0 0.5 1.0 Figure 1: Distribution of the angle between n and lepton: (a) forn° Ie- and n+ I e- combined; (b) for 15°/ e- and n-/ e- combined. decay modes n° K-7r+ and n+ K-7r+7r+. To avoid the ambiguity between n° and 15°, ---t ---t we use a tight hadron identification using dE/dx and Time-of-flight and uniquely determine whether a given K7r state is K-7r+ or K+7r-. We determine n° and n+ detection efficiencies as a function of n momentum and polar angle and correct for the efficiency event by event. This allows us to combine the yield of n° and n+ for a combined analysis. Figure 1 shows the combined n° and n+ yield with a tagging lepton of Pt > 1.5 GeV /c, as a fu nction of cosine of the angle between the n and lepton. Figure 1 (a) is for e-/ n° and e-/ n+ combinations. This is expected mostly for lepton and n from the same B, hence a strong peaking behavior towards cos !Jn t -1 (back-to-back n and l). We decomposed the - � distribution into "same B" and "other B" components, based on the shapes determined from Monte-Carlo. Note that while the same B component dominates the distribution, there is a non-zero excess of other B component shown with an almost isotropic fitting function. Similarly, Fig. 1 (b) is for e-I 15° and e-In- combinations. We expect this n-lepton charge correlation only when the n and lepton are produced by decays of two different B's. Naturally, the distribution is mostly explained by an isotropic fitting function (other B com­ ponent) and the contribution of same B component is consistent with zero, as expected. Table 2 summarizes the same B and other B decompositions of n-lepton yields in two charge configurations. 5 n° and n+ in the Upper Vertex Let x be the ratio of the other B component of n / e- yield to the other B component of D/ e­ yield: N(e-;n, other B) x _ = N(e-/ n, other B) " 323 Table 2: Results D-lepton yields from "same B" and "other B" D, e-) "same B" (276.0 ± 7.5) x103 ( "other B" (48.6 ± 6.l)x103 e-) "same B" (2.9 ± 5.5) x 103 (fJ, "other B" (225.4 ± 7.3) x 103 We obtain the ratio of upper vertex D production to lower vertex D production using the following formula: f(B DX) (x - Fm) --t (2) f(B DX) (1 -xFm )' --t where Fm is a correction factor for BB mixing and lepton-mistag probabilities (Fm � 0.11). Using the results in Table 2, we have measured x = 0.216 ± 0.028 and consequently, f(B DX) --t 0.107 ± 0.029 ± 0.018 (3) f(B DX = --t ) where the first error is statistical and the second error is systematical. Using the relation DX) (B D X) (B D X) baryons (B DX B(B bsL(2.25 + - ; - (B --t + ) --t = + rud) --t ; --t ) --t and taking = 4.0 ± 0.4 as in Table 1, we solve for B(B DX) and obtain rus --t B(B DX) (8.1 ± 2.6) %. (4) --t = 6 Search b Decays for --t sg Let us define Pgen to be the probability of lower vertex D meson production in a generic B decay, and to be the probability of lower vertex D production in a semileptonic B decay Ps L 4• We expect Pgen and PsL to be close to 100 % except forthe following corrections: Pgen 1 - 2 D,; low. vtx.) - (ce) - baryons - (b (5) IVub/Vcbl2 -( --t sg) 3 1 Ps L 1 - x 2 x - D,; low. vtx. 2 IV..b/Vcbl2 2( ) (6) Using the results in Table 2, we have measured N(e- other B) / fJ, 0.834 ± 0.034 N(f- D, same B) = / 4With a requirement of 1.5 2.8 GeV /c.
Load more

Recommended publications
  • Flavour Physics
    May 21, 2015 0:29 World Scientific Review Volume - 9in x 6in submit page 1 TASI Lectures on Flavor Physics Zoltan Ligeti Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 ∗E-mail: [email protected] These notes overlap with lectures given at the TASI summer schools in 2014 and 2011, as well as at the European School of High Energy Physics in 2013. This is primarily an attempt at transcribing my hand- written notes, with emphasis on topics and ideas discussed in the lec- tures. It is not a comprehensive introduction or review of the field, nor does it include a complete list of references. I hope, however, that some may find it useful to better understand the reasons for excitement about recent progress and future opportunities in flavor physics. Preface There are many books and reviews on flavor physics (e.g., Refs. [1; 2; 3; 4; 5; 6; 7; 8; 9]). The main points I would like to explain in these lectures are: • CP violation and flavor-changing neutral currents (FCNC) are sen- sitive probes of short-distance physics, both in the standard model (SM) and in beyond standard model (BSM) scenarios. • The data taught us a lot about not directly seen physics in the past, and are likely crucial to understand LHC new physics (NP) signals. • In most FCNC processes BSM/SM ∼ O(20%) is still allowed today, the sensitivity will improve to the few percent level in the future. arXiv:1502.01372v2 [hep-ph] 19 May 2015 • Measurements are sensitive to very high scales, and might find unambiguous signals of BSM physics, even outside the LHC reach.
    [Show full text]
  • Incomplete Document
    Improved measurement of the Pseudoscalar Decay Constants fDS from D∗+ γµ+ ν data sample s → Abstract + − Determination of fDS using 14 million e e cc¯ events obtained with the CLEO → II and CLEO II.V detector is presented. New measurement of the branching ratio gives Γ (D+ µ+ν)/Γ (D+ φπ+) = 0.137 0.013 0.022. Using Γ (D+ µ+ν) = 0.036 S → S → ± ± S → 0.09, fDS was calculated and found to be (247 12 20 31) MeV. Comparison ± ± ± ± of these results with other theoretical and experimental results are also presented. 1 Introduction Purely leptonic decay modes of heavy mesons predict their decay constants, which is connected with measured quantities such as CKM matrix elements. Currently it is not possible to measure fB experimentally, but measurements of the Cabibbo-flavor pseudoscalar decay constants such as fDS is possible. This measurement provides a check of these theoretical calculations and helps to establish different theoretical models. + The decay width of Ds is given by [1] G2 m2 Γ(D+ ℓ+ν)= F f 2 m2M 1 ℓ V 2 (1) s 6π DS ℓ DS 2 cs → − MDS ! | | where MDS is the Ds mass, mℓ is the mass of the final state lepton, Vcs is a CKM matrix element equal to 0.974 [2] and GF is the Fermi coupling constant. Various theoretical predictions of fDS range from 190 MeV to 350 MeV. The relative widths of three lepton flavors are 10 : 1 : 10−5 for tau, muon and electron respectively. Helicity suppression reduces smaller width for low mass electron.
    [Show full text]
  • Design and Application of the Reconstruction Software for the Babar Calorimeter
    Design and application of the reconstruction software for the BaBar calorimeter Philip David Strother Imperial College, November 1998 A thesis submitted for the degree of Doctor of Philosophy of the University of London, and Diploma of Imperial College 2 Abstract + The BaBar high energy physics experiment will be in operation at the PEP-II asymmetric e e− collider in Spring 1999. The primary purpose of the experiment is the investigation of CP violation in the neutral B meson system. The electromagnetic calorimeter forms a central part of the experiment and new techniques are employed in data acquisition and reconstruction software to maximise the capability of this device. The use of a matched digital filter in the feature extraction in the front end electronics is presented. The performance of the filter in the presence of the expected high levels of soft photon background from the machine is evaluated. The high luminosity of the PEP-II machine and the demands on the precision of the calorimeter require reliable software that allows for increased physics capability. BaBar has selected C++ as its primary programming language and object oriented analysis and design as its coding paradigm. The application of this technology to the reconstruction software for the calorimeter is presented. The design of the systems for clustering, cluster division, track matching, particle identification and global calibration is discussed with emphasis on the provisions in the design for increased physics capability as levels of understanding of the detector increase. The CP violating channel Bo J=ΨKo has been studied in the two lepton, two π0 final state.
    [Show full text]
  • Charged Particle Tracking in the CLEO II Detector
    Charged Particle Tracking in the CLEO II Detector for Neutrino Reconstruction Michell Morgan Computer Science Department, Wayne State University, Detroit, Michigan, 48204 Abstract In neutrino reconstruction analyses, we rely on information from tracks from other particles in the event to determine the neutrino momentum. It is very important to nd out as much information as possible about those tracks for neutrino reconstruction. Currently, events with one or more tracks with no z t are not used, leading to an ineciency of about 15%. However, such tracks do have hits with z information on charge division wires which are ignored by the tracking program, because charge division hits z information has been observed to be very inaccurate on occasion. We have traced the inaccuracies to the z calibration which was performed only for central tracks and involved tting with a cubic polynomial. However, for forward tracks, the cubic leads to hits with z positions very far from the actual path of the track. We have investigated solutions to this problem so that we may be able to recover some z information on tracks in events that we currently throw away and use them in neutrino reconstruction. Introduction Neutrinos are neutral particles that pass through the detector at the speed of light. Because neutrinos are neutral and weakly interacting, they do not leave tracks in the detector nor hits in the calorimeter. Thus, for neutrino reconstruction, we have to know the energy and momentum of the other particles in the event. The total momentum of the colliding system is zero and thus the nal particles in the event must balance.
    [Show full text]
  • Measurement of Production and Decay Properties of Bs Mesons Decaying Into J/Psi Phi with the CMS Detector at the LHC
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2012 Measurement of Production and Decay Properties of Bs Mesons Decaying into J/Psi Phi with the CMS Detector at the LHC Giordano Cerizza University of Tennessee - Knoxville, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Part of the Elementary Particles and Fields and String Theory Commons Recommended Citation Cerizza, Giordano, "Measurement of Production and Decay Properties of Bs Mesons Decaying into J/Psi Phi with the CMS Detector at the LHC. " PhD diss., University of Tennessee, 2012. https://trace.tennessee.edu/utk_graddiss/1279 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Giordano Cerizza entitled "Measurement of Production and Decay Properties of Bs Mesons Decaying into J/Psi Phi with the CMS Detector at the LHC." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Physics. Stefan M. Spanier, Major Professor We have read this dissertation and recommend its acceptance: Marianne Breinig, George Siopsis, Robert Hinde Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Measurements of Production and Decay Properties of Bs Mesons Decaying into J/Psi Phi with the CMS Detector at the LHC A Thesis Presented for The Doctor of Philosophy Degree The University of Tennessee, Knoxville Giordano Cerizza May 2012 c by Giordano Cerizza, 2012 All Rights Reserved.
    [Show full text]
  • QCD Studies in Two-Photon Collisions at CLEO Vladimir Savinov University of Pittsburgh, Pittsburgh
    W03 hep-ex/0106013 QCD Studies in Two-Photon Collisions at CLEO Vladimir Savinov University of Pittsburgh, Pittsburgh We review the results of two-photon measurements performed up to date by the CLEO experiment at Cornell University, Ithaca, NY.These + − measurements provide an almost background-free virtual laboratory to study strong interactions in the process of the e e scattering. We discuss the measurements of two-photon partial widths of charmonium, cross sections for hadron pairs production, antisearch for glueballs ∗ and the measurements of γ γ → pseudoscalar meson transition form factors. We emphasize the importance of other possible analyses, favorable trigger conditions and selection criteria of the presently running experiment and the advantages of CLEOc—the future τ-charm factory with the existing CLEO III detector. 1. INTRODUCTION a time-of-flight (TOF) plastic scintillator system and a muon system (proportional counters embedded at various depths in One of the ways to study properties of strong interactions, the steel absorber). Two thirds of the data were taken with the surprisingly, is to collide high energy photons. Photons do not CLEO II.V configuration of the detector where the innermost interact strongly, however, in the presence of other photons drift chamber was replaced by a silicon vertex detector [4] and they can fluctuate into quark pairs that have a sizable probabil- the argon-ethane gas of the main drift chamber was changed ity to realize as hadrons. Space-like photons of relatively high to a helium-propane mixture. This upgrade led to improved energies can be obtained in the process of the e+e− scattering, resolutions in momentum and specific ionization energy loss that is, in the e+e− → e+e−hadrons reactions, where hadrons (dE/dx) measurements.
    [Show full text]
  • Charm and QCD at CLEO-III and CLEO-C Jim Napolitano (RPI
    Charm and QCD at CLEO-III and CLEO-c Jim Napolitano (RPI & Cornell) Physics topics: 0 − − + 1) Measurement of Ξc → pK K π (CLEO-III) 2) Form factors in D0 → {π−,K−}e+ν (CLEO-III ⇒ CLEO-c) 3) Disentangling glueballs and qq¯ states (CLEO-c) XXXIX Rencontres de Moriond QCD and High Energy Hadronic Interactions 28 March - 04 April, 2004 1 2230902-007 109 CLEO Integrated Luminosities CLEO Physics (1D) 8 CLEO Upgrades 10 ACP Limits RICH CESR Upgrades B I New DD Mixing Tracking Limit B K* 2cm BP CLEO III bs Silicon 7 He-propane 10 B K 9x5 Bunches B K SC IR Quads ear B / CLEO II.V Y SC RF I CsI 9x4 Bunches 3.5cm BP I BB / Crossing Angle 106 (BB Mixing) CLEO II 9X3 Bunches b u New Tracking 1 IR Ds CLEO I.V 5 b c 10 B Decay (4S), (5S) Microbeta CLEO I 7 Bunches Pretzel Orbits 104 1980 1985 1990 2 1995 2000 2005 CLEO III Solenoid 2230801-005 Coil RICH Calorimeter Drift Chamber Muon SC and Chambers Rare Earth Quads Silicon Magnet Vertex Detector Iron 3 0 − − + 1) Measurement of Ξc → pK K π See arXiv:hep-ex/0309020, to appear in Physical Review D 0 − ¯? 0 Physics: The decay Ξc → pK K (892) cannot proceed through external W decay, so it is “color suppressed”. ⇒ Want to separate it from nonresonant four-body decays. 0 − − + 0 − + Measured Ξc → pK K π rate relative to Ξc → Ξ π Needs extensive p, K, π particle identification made possible by RICH in CLEO-III Only previous result: ACCMOR 1990 (four events, all K¯ ?) 4 0 RESULTS: Ξc Decay 0 Ξc Decay modes 150 0990803-002 pK−K−π+ ) 2 100 K−π+ mass distribution: 50 Entries / 6 (MeV/c 0 2.30 2.40 2.50 2.60 I M(pK K I +) (GeV/c2) 100 0991203-003 Ξ−π+ ) 75 2 0 − − + B(Ξc → pK K π )/ 0 − + 50 B(Ξc → Ξ π ) = 0.35±0.06±0.03 25 Entries / 6 (MeV/c B(Ξ0 → pK−K−π+; No K¯ ?)/ 0 c 2.30 2.40 2.50 2.60 0 − + M( I +) (GeV/c2) B(Ξc → Ξ π ) = 0.21±0.04±0.02 5 2) Form Factors in D0 → {π−,K−}e+ν New CLEO-III analysis to be published soon.
    [Show full text]
  • The CLEO RICH Detector Design
    SUHEP 20-2005 June, 2005 THE CLEO RICH DETECTOR M. Artuso a, R. Ayad a, K. Bukin a, A. Efimov a, C. Boulahouache a, E. Dambasuren a, S. Kopp a, Ji Li a, G. Majumder a, N. Menaa a, R. Mountain a, S. Schuh a, a a, a a T. Skwarnicki , S. Stone ∗, G. Viehhauser , J.C. Wang aDepartment of Physics, Syracuse University, Syracuse, NY 13244-1130, USA T.E. Coan b, V. Fadeyev b, Y. Maravin b, I. Volobouev b, J. Ye b bDepartment of Physics, Southern Methodist University, Dallas, TX 75275-0175, USA S. Anderson c, Y. Kubota c, A. Smith c cSchool of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455-0112, USA Abstract We describe the design, construction and performance of a Ring Imaging Cherenkov Detector (RICH) constructed to identify charged particles in the CLEO experiment. Cherenkov radiation occurs in LiF crystals, both planar and ones with a novel “sawtooth”-shaped exit surface. Photons in the wavelength interval 135–165 nm are detected using multi-wire chambers filled with a mixture of methane gas and triethylamine vapor. Excellent π/K separation is demonstrated. arXiv:physics/0506132v2 [physics.ins-det] 26 Jul 2005 Key words: Cherenkov, Particle-identification PACS: 03.30+p, 07.85YK ∗ Corresponding author. Email address: [email protected] (S. Stone). Preprint submitted to Elsevier Science 15 August 2018 1 INTRODUCTION The CLEO II detector was revolutionary in that it was the first to couple a large magnetic tracking volume with a precision crystal electromagnetic calorimeter capable of measuring photons down to the tens of MeV level [1].
    [Show full text]
  • Recent Cleo Results on Hadron Spectroscopy∗
    Vol. 36 (2005) ACTA PHYSICA POLONICA B No 7 RECENT CLEO RESULTS ON HADRON SPECTROSCOPY∗ Tomasz Skwarnicki Department of Physics, 201 Physics Building, Syracuse University Syracuse, NY 13244, USA (Received May 18, 2005) Selected CLEO results on hadron spectroscopy are reviewed. PACS numbers: 14.40.Gx, 13.20.Gd, 13.25.Ft 1. Introduction The CLEO experiment at CESR has been in operation for over a quarter of century. Most of its past running was performed at the Υ(4S) for B meson physics, with smaller amount of data taken at the narrow Υ(1S, 2S, 3S) resonances and at the Υ(5S). With advent of two-ring B-factories at KEK and SLAC, single-ring CESR could not keep up with luminosity. CESR instantaneous peak luminosity at the Υ(4S) is 1.2×1033 cm−2s−1 compared to a KEK-B (PEP-II) record of 1.5 (0.9) × 1034 cm−2s−1. Therefore, the B-physics runs ended in mid 2001. Longer runs at the narrow Υ resonances followed, increasing the data sizes available for these resonances by an order of magnitude; 29 × 106, 9 × 106 and 6 × 106 resonant decays were recorded for Υ(1S), Υ(2S) and Υ(3S), respectively. Some data were also taken at the Υ(5S) (and above) for exploration of Bs (Λb) production rates. Then, CESR was reconfigured by insertion of additional wiggler magnets to operate at lower beam energies in the charm threshold region. Initial test runs with one new wiggler, performed in fall 2002, provided useful ψ(2S) data.
    [Show full text]
  • Arxiv:1610.02629V2 [Hep-Ph] 7 May 2018
    Three Lectures of Flavor and CP violation within and Beyond the Standard Model S. Gori Department of Physics, University of Cincinnati, Cincinnati, Ohio, USA Abstract In these lectures I discuss 1) flavor physics within the Standard Model, 2) effective field theories and Minimal Flavor Violation, 3) flavor physics in the- ories beyond the Standard Model and “high energy" flavor transitions of the top quark and of the Higgs boson. As a bi-product, I present the most updated + − constraints from the measurements of Bs ! µ µ , as well as the most recent development in the LHC searches for top flavor changing couplings. Keywords Lectures; heavy flavor; CP violation; flavor changing couplings. 1 Introduction My plan for these lectures is to introduce you to the basics of flavor physics and CP violation. These three lectures that I gave at the 2015 European School of High-Energy Physics are not comprehensive, but should serve to give an overview of the interesting open questions in flavor physics and of the huge experimental program measuring flavor and CP violating transitions. Hopefully they will spark your curiosity to learn more about flavor physics. There are many books and reviews about flavor physics for those of you interested [1–6]. Flavor physics is the study of different generations, or “flavors", of quarks and leptons, their spectrum and their transitions. There are six different types of quarks: up (u), down (d), strange (s), charm (c), bottom (b) and top (t) and three different type of charged leptons: electron, muon and tau. In these lectures, I will concentrate on the discussion of quarks and the mesons that contain them.
    [Show full text]
  • Study of the Glueball Candidate Fj(2220) at CLEO
    PROCEEDINGS SUPPLEMENTS ELSEVIER Nuclear Physics B (Proc. Suppl.) 82 (2000) 33%343 www.dsevier.ni/locate/npe Study of the glueball candidate fJ(2220) at CLEO Hans P. Paar a aPhysics Department 0319, University of California San Diego, 9500 Gilman Drive, La Jolla CA 92093-0319. (e-mail address: [email protected]) The CLEO detector at the Cornell e+e - storage ring CESR was used to search for the two-photon production of the glueball candidate fJ(2220) in its decay to K~K~ and 7r+Tr-. I present restrictive upper limits on the product of the two-photon width and the respective branching fraction [F77BK~K~]fj(2220 ) < 1.3 eV, 95% CL and [FT~BTr+Tr-]fj(2220) < 2.beV, 95% CL. When these two limits are combined to calculate a lower limit on the Stickiness, a measure of the two-gluon coupling relative to the two-photon coupling, a lower limit SFJ(2220) > 102, 95% CL is found. A new measure of this ratio of couplings is the Gluiness; a combined lower limit of Gfj(2220) > 66, 95% CL is found. These limits on the Stickiness and the Gluiness indicate that the fJ(2220) is likely to have substantial neutral patton or glueball content. 1. INTRODUCTION while spin 0 is unlikely [7]. QCD predicts (using lattice calculations) that a tensor glueball exists The unequivocal demonstration that glueballs and that it should have a mass near 2.2 GeV [8]. exist would prove the existence of a new form A pure glueball will couple to photons only of matter.
    [Show full text]
  • Construction, Pattern Recognition and Performance of the CLEO III Lif-TEA RICH Detector M
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server 1 Construction, Pattern Recognition and Performance of the CLEO III LiF-TEA RICH Detector M. Artuso, R. Ayad, K. Bukin, A. Efimov, C. Boulahouache, E. Dambasuren, S. Kopp, R. Mountain, G. Majumder, S. Schuh, T. Skwarnicki, S. Stone, G. Viehhauser, J. C. Wang, and a T. E. Coan, V. Fadeyev, Y. Maravin, I. Volobouev, J. Ye, and b S. Anderson, Y. Kubota, and A. Smith c aSyracuse University, Syracuse, NY 13244-1130, U. S. A. bSouthern Methodist University, Dallas, TX 75275-0175 cUniversity of Minnesota, Minneapolis, MN 55455-0112 We briefly describe the design, construction and performance of the LiF-Tea RICH detector built to identify charged particles in the CLEO III experiment. Excellent π/K separation is demonstrated. 1. INTRODUCTION 2. DETECTOR DESCRIPTION 1.1. The CLEO III Detector 2.1. Detector Elements The CLEO III detector was designed to study decays of b and c quarks, τ leptons and Υ mesons G10 Box Rib + Photon Detector produced in e e− collisions near 10 GeV center- Charged of-mass energy. The new detector is an upgraded Particle 20 µm wires CH 4 +TEA Fiberglass 16 cm Cherenkov Pure N Siderail version of CLEO II [1]. It contains a new four- 2 Photon CaF Window 2 layer silicon strip vertex detector, a new wire LiF Radiator 192 mm drift chamber and a particle identification sys- tem based on the detection of Cherenkov ring images. Information about CLEO III is available Photon elsewhere [2,3].
    [Show full text]