Challenges in Semileptonic B decays

Europe/Berlin
02.430 (Mainz Institute for Theoretical Physics<br>Johannes Gutenberg University)

02.430

Mainz Institute for Theoretical Physics<br>Johannes Gutenberg University

Staudingerweg 9 / 2<sup>nd</sup> floor 55128 Mainz
Description
Two of the elements of the Cabibbo-Kobayasha-Maskawa (CKM) quark mixing matrix, Vub and Vcb, are extracted from semi-leptonic B decays. The results of the B factories, analysed in the light of the most recent theoretical calculations, are puzzling. For both |Vcb| and |Vub| the exclusive determination is about 3σ below the inclusive one. This discrepancy has survived several independent checks and could be an indication for New Physics. Fortunately, the upcoming experiment Belle-II has the potential to resolve the issue in the first few years of operation after its start in 2015.

The goal of the proposed workshop is to help developing a medium term strategy of analyses and calculations aimed at the resolution of the puzzle. We plan to have lattice and continuum theorists working together with experimentalists to discuss how to reshape the semi-leptonic analyses in view of the much larger luminosity expected at Belle-II, searching for ways to systematically validate the theoretical predictions in both exclusive and inclusive B decays. We will also discuss the challenges and opportunities theoretical and experimental — of semileptonic Bs, Bc, and Λ b decays, motivated especially be the large samples already available at LHCb.
Dates of Participants
Execetive Summary
    • Registration
    • Welcome
      Conveners: Andreas Kronfeld (Fermilab), Dr Christoph Schwanda (Institute of High Energy Physics, Austrian Academy of Sciences), Dr Marcello Rotondo (I.N.F.N. Padova), Paolo Gambino (University of Turin), Sascha Turczyk (University of Mainz)
      • 1
        Welcome and Information
        Speakers: Andreas Kronfeld (Fermilab), Dr Christoph Schwanda (Institute of High Energy Physics, Austrian Academy of Sciences), Dr Marcello Rotondo (I.N.F.N. Padova), Paolo Gambino (University of Turin), Sascha Turczyk (University of Mainz)
      • 2
        Information on Belle II-Theory interface Platform (B2TiP)
        Speaker: Shoji Hashimoto (KEK)
    • Vcb inclusive
      • 3
        Vcb inclusive: Where we stand
        Speaker: Paolo Gambino (University of Turin)
        Slides
      • 4
        Higher Power Corrections
        Speaker: Sascha Turczyk (University of Mainz)
        Slides
    • Break
    • Vcb inclusive
      • 5
        Lattice inputs on heavy quark masses
        Speaker: Andreas Kronfeld (Fermilab)
        Slides
      • 6
        Future Prospects for moments measurements
        Speaker: Dr Christoph Schwanda (Institute of High Energy Physics, Austrian Academy of Sciences)
        Slides
      • 7
        Questions & Discussion
    • Discussions: Vcb inclusive
      Conveners: Dr Christoph Schwanda (Institute of High Energy Physics, Austrian Academy of Sciences), Thomas Mannel (Siegen University)
      notes
      slides
    • Vcb exclusive
      • 8
        Status and prospects of lattice FF calculations for B-> D, D*, Lambda_b -> Lambda_c, B_c
        Speaker: Carlos Pena (Universidad Autónoma de Madrid)
        Slides
      • 9
        Status and prospects of non-lattice FF calculations
        Speaker: Thomas Mannel (Siegen University)
        Slides
    • Break
    • Vcb exclusive
      • 10
        Experimental issues @ Belle-II and D**
        Speaker: Dr Florian Bernlochner (University of Bonn)
        Slides
      • 11
        Experimental issues @ LHCb
        Speaker: Jeroen Van Tilburg (Nikhef)
        Slides
      • 12
        Questions & Discussion
    • Discussions: Vcb exclusive
      Conveners: Aida El-Khadra (University of Illinois), Robert Kowalewski (University of Victoria)
      notes
      slides
    • Vub inclusive
      • 13
        Inclusive determination of |Vub| – theoretical issues
        Speaker: Einan Gardi (University of Edinburgh)
        Slides
      • 14
        Inclusive |Vub| from SIMBA
        Speaker: Zoltan Ligeti (LBNL)
        Slides
      • 15
        Precision Determination of Inclusive |Vub|
        Speaker: Gil Paz (Wayne State University)
        Slides
    • Break
    • Vub inclusive
      • 16
        NNVub, a method to extract information on the shape function(s) using neural nets
        Speaker: Kristopher Healey (University of Torino, INFN Torino)
        Slides
      • 17
        Experimental prospects and issues at Belle-II
        Speaker: Phillip Urquijo (The University of Melbourne)
        Slides
      • 18
        Questions & Discussion
    • HFAG Meeting
    • Discussions: Vub inclusive
      Conveners: Concezio Bozzi (INFN Sezione di Ferrara), Frank Tackmann (DESY)
      notes
    • Vub exclusive
      • 19
        Status and prospects of lattice FF calculations for B->pi, rho, Bs->K(*), Lambda_b->p
        Speaker: Daping Du (Syracuse University)
        Slides
      • 20
        LCSR calculations
        Speaker: Alexander Khodjamirian (University of Siegen)
        Slides
    • Break
    • Vub exclusive
      • 21
        Experimental issues at Belle-II
        Speaker: Jochen Dingfelder (Physikalisches Institut Bonn)
        Slides
      • 22
        Experimental issues at LHC-b
        Speaker: Ulrik Egede (Imperial College London)
        Slides
      • 23
        Questions & Discussion
    • Discussions: Vub exclusive
      Conveners: Dr Marcello Rotondo (I.N.F.N. Padova), Silvano Simula (INFN - Sezione di Roma Tre)
      notes
      slides
    • Semileptonic and leptonic decays to tau
      • 24
        Status and prospects of lattice FF for B->D tau nu and of B decay constant
        Speaker: Gregorio Herdoiza (IFT, Madrid)
        Slides
      • 25
        Experimental issues of tau analyses at the B-Factories
        Speaker: Vera Luth (SLAC - Stanford University)
        Slides
    • Break
    • Semileptonic and leptonic decays to tau
      • 26
        Exclusive decays with taus in final states @ LHCb
        Speaker: Greg Ciezarek (Nikhef)
        Slides
      • 27
        Questions & Discussion
    • Final Discussion
      Conveners: Andreas Kronfeld (Fermilab), Dr Christoph Schwanda (Institute of High Energy Physics, Austrian Academy of Sciences), Dr Marcello Rotondo (I.N.F.N. Padova), Paolo Gambino (University of Turin), Sascha Turczyk (University of Mainz)
      slides