Status of the Hadronic Tau Determination of V_us.pdfVIP

STATUS OF THE HADRONIC τ DETERMINATION OF |Vus | K. Maltman∗ Department of Mathematics and Statistics, York University, 4700 Keele St., Toronto, Ontario M3J 1P3, Canada C.E. Wolfe 8 0 Department of Physics and Astronomy, York University, 4700 Keele St., 0 2 Toronto, Ontario M3J 1P3, Canada l u S. Banerjee, J.M. Roney and I. Nugent J 1 Department of Physics and Astronomy, University of Victoria, 2 PO Box 3055, STN CSC, Victoria, BC V8W 3P6, Canada ] (Dated: July 21, 2008) h p - We update the extraction of |Vus | from hadronic τ decay data in light of recent p BaBar and Belle results on the branching fractions of a number of important strange e h decay modes. A range of sum rule analyses is performed, particular attention being [ paid to those based on “non-spectral weights”, developed previously to bring the 1 slow convergence of the relevant integrated D = 2 OPE series under improved con- v 5 trol. Results from the various sum rules are shown to be in good agreement with 9 one another, but ∼ 3σ below expectations based on 3-family unitarity. Important 1 3 avenues for future study are briefly discussed. . 7 0 PACS numbers: 12.15.Hh,13.35.Dx,11.55.Hx 8 0 : I. INTRODUCTION v i X Once B factory data is fully analyzed, the precision of the hadronic τ decay deter- r a mination of |Vus | is expected