21โ€“25 May 2007
Laboratori Nazionali di Frascati dell'INFN
Europe/Rome timezone

Session

Session I

2
21 May 2007, 14:30
High Energy Building - Aula Bruno Touschek (Laboratori Nazionali di Frascati dell'INFN)

High Energy Building - Aula Bruno Touschek

Laboratori Nazionali di Frascati dell'INFN

Via E. Fermi, 40 00044 Frascati

Conveners

Session I: Vus

  • Juliet Lee-Franzini (LNF-INFN, Frascati)
  • Matthew Moulson (LNF-INFN, Frascati)

Session I: Vus and Vud

  • Mario Antonelli (LNF-INFN, Frascati)

Presentation materials

There are no materials yet.

  1. Dr Vincenzo Cirigliano (Los Alamos)
    21/05/2007, 14:30
    Vus and Vud
  2. Prof. Antonio Pich (Valencia University, IFIC)
    21/05/2007, 15:00
    Vus and Vud
  3. Swagato Banerjee (University of Victoria)
    21/05/2007, 15:30
    Vus and Vud
    We report measurements of branching fractions for several hadronic tau decays to final states including kaons, which can be used to determine the strange quark mass and the element |Vus| of the CKM quark mixing matrix. The results are collected with the Babar detector at PEP-II, the SLAC asymmetric-energy e+e- collider.
    Go to contribution page
  4. Andreas Juettner (Univ. of Southampton)
    21/05/2007, 15:50
    Vus and Vud
    We present the latest results from UKQCD/RBC collaborations for the Kl3 form factor with 2+1 flavours of dynamical domain wall quarks. Simulations are performed on 16^3x32x16 and 24^3x64x16 lattices with three values of the light quark mass, allowing for an extrapolation to the chiral limit
    Go to contribution page
  5. Ms Anne Dabrowski (Department of Physics and Astronomy, Northwestern University)
    21/05/2007, 16:10
    Vus and Vud
    Measured ratios of decay rates for ${\cal R}_{K e 3 / K2\pi}$, ${\cal R}_{K \mu 3 / K2\pi}$ and ${\cal R}_{K \mu 3 / Ke3}$ are presented, based on $K^\pm$ decays collected in a dedicated run in 2003 by the NA48/2 experiment at CERN. The results obtained are $ {\cal R}_{K e 3 / K2\pi} = 0.2470\pm 0.0009 (stat)\pm 0.0004 (syst)$ and $ {\cal R}_{K \mu 3 / K2\pi} = 0.1637\pm 0.0006...
    Go to contribution page
  6. Emilie Passemar (IPN Orsay)
    21/05/2007, 17:00
    Vus and Vud
    In this talk we will introduce an accurate dispersive parametrization of the two K_{l3} form factors and discuss three applications to the analysis of K_{e3} and K_{mu3} measurements: the prediction of the branching ratios K_{mu3}/K_{e3}, the extraction of |f_+(0)V_{us}| and finally the possible measurement of m_d - m_u induced isospin breaking asymmetry.
    Go to contribution page
  7. Jan Stern (IPN Orsay)
    21/05/2007, 17:20
    Vus and Vud
    The recent dedicated analysis of K^L_{$\mu$ 3} Dalitz plot by NA48 reveals a 5 $\sigma$ deviation from the Callan-Treiman low-energy theorem , provided standard electroweak couplings of quarks are assumed. QCD can hardly tolerate such a huge violation of its $ SU(2) X SU(2) $ chiral symmetry. We suggest that , instead, the observed discrepancy reflects a small admixture of right -...
    Go to contribution page
  8. Dr Barbara Sciascia (LNF - INFN, Frascati)
    21/05/2007, 17:50
    Vus and Vud
    The semileptonic BR's are relevant for the evaluation of the CKM matrix element |Vus|. The measurement of the branching ratios for the charged K semileptonic decays uses four independent samples tagged by the following kaon decays: K+ -> mu2, K+ -> pi2, K- -> mu2, and K- -> pi2. Using 410 pb-1 of total integrated luminosity (2.5 fb-1), about 60 million tag decays have been identified...
    Go to contribution page
  9. Mr Viacheslav Duk (INR RAS)
    21/05/2007, 18:10
    Vus and Vud
    We review recent results on charged kaon decays obtained by ISTRA+ collaboration. The obtained branching fractions are compared with theoretical predictions. For Kl3 radiative decays the estimations of T-odd asymmetry are given.
    Go to contribution page
  10. Dr Claudio Gatti (LNF - INFN, Frascati)
    21/05/2007, 18:30
    Vus and Vud
    Semileptonic kaon decays offer possibly the cleanest way to obtain an accurate value of the Cabibbo angle, or better, $V_{us}$. At present, the largest uncertainty in calculating $V_{us}$ from the decay rate, is due to the difficulties in computing the matrix element of the $K \rightarrow \pi$ transition. The matrix element of $K_L \rightarrow \pi \mu \nu$ decay is expressed in...
    Go to contribution page
  11. Paolo Massarotti (Naples University & INFN)
    21/05/2007, 18:50
    Vus and Vud
    The charged K lifetime, is an experimental input to the determination of Vus. The present fractional uncertainty is about 0.2%, however the available data show large discrepancies between the measurements done using charged kaon decays in-flight and at-rest. At KLOE two different methods have been developed: one based on the measurement of the charged kaon decay length and the other...
    Go to contribution page
  12. Prof. Takashi Kaneko (KEK, Tsukuba)
    22/05/2007, 09:00
    Vus and Vud
  13. Dr Takeyasu Ito (Los Alamos)
    22/05/2007, 09:30
    Vus and Vud
  14. Dr Matteo Palutan (LNF -INFN)
    22/05/2007, 10:00
    Vus and Vud
    At present, the first-row constraint, $|V_{ud}|^2 + |V_{us}|^2 + |V_{ub}|^2$ = 1 (with $|V_{ub}|^2$ negligible), offers the most precise test of CKM unitarity. Up until 2002 (and for the 2004 PDG evaluation), the evaluation of $|V_{us}$ from older $K_{l3}$ data gave 2.3$\sigma$ hint of unitarity violation in the first-row test. The 2003 measurement of BR($K^+_{e2}$) by BNL E865 gave a...
    Go to contribution page
Building timetable...