Conveners
WG2
- Michele Della Morte (Unknown)
WG2
- Phillip Urquijo (University of Melbourne (AU))
WG2
- Michele Della Morte (Unknown)
WG2
- Alexander Khodjamirian (University of Siegen)
WG2
- Michele Della Morte (Unknown)
Martin Heck
(Karlsruhe Institute of Technology)
08/09/2014, 14:30
Leptonic decays of B mesons are well understood in the Standard Model (SM) and highly suppressed due to helicity conservation. The leptonic branching fraction measurements can provide stringent constraints on New Physics, where particles or forces outside of the SM can suppress or enhance the decay rate. Experimentally, due to the small branching fractions, it is a challenge to measure the...
Alexander Khodjamirian
(University of Siegen)
08/09/2014, 15:26
I will present the current status of the B\to \pi form factors calculated from QCD LCSR at large hadronic recoil. New updated uncertainty estimates and extrapolations of the form factors are obtained, together with model-independent unitarity bounds. Related results for the other heavy-to-light hadronic matrix elements will be overviewed.
Paolo Gambino
(Universita e INFN (IT))
08/09/2014, 17:05
The extraction of Vcb from fits to inclusive semileptonic B decays is reviewed, with emphasis on recent developments and in particular on the effect of higher order corrections and on heavy mass constraints.
Daping Du
(University of Illinois, Urbana-Champaign)
08/09/2014, 17:50
I will discuss the recent results for the B->D*lv and B->Dlv semileptonic form factors and the determination of |V_cb| from the Fermilab/MILC collaborations. These lattice calculations use an improved staggered action for the light quarks and the Fermilab action for the charm and bottom quarks; the calculation uses the MILC (asqtad) ensembles with three flavors of sea quarks and five lattice...
Dr
Florian Urs Bernlochner
(Universitaet Bonn (DE))
08/09/2014, 18:10
The experimental knowledge of semileptonic B decays to a D or D* meson with one or more pions is limited. These limitations are relevant to two experimental puzzles: the tension between the values of Vcb determined from inclusive and exclusive semileptonic decays, and the gap between the sum of the exclusive semileptonic B decays to charm and the inclusive b -> c l nu rate. The full...
Mr
Bahman Dehnadi
(University of Vienna)
08/09/2014, 18:29
We briefly review recent charm and bottom mass determinations based on perturbative QCD. We give new results on MSbar charm mass using as input lattice moments of the pseudoscalar current correlator. We also give an update on the MSbar bottom mass based on e+e- data, which quantifies the uncertainties from energies where no measurements exist and uses latest theory input. Both analyses are...
Basem Khanji
(Universita & INFN, Milano-Bicocca (IT))
10/09/2014, 09:00
LHCb has recorded large samples of semileptonic decays of c- and b-flavoured hadrons. We review the latest results in semileptonic decays of B, Bs and Λb decays. Recent results on CP violation and determination of CKM matrix elements are shown.
Alexander Ermakov
(Bonn)
10/09/2014, 09:25
In this talk I give an experimental review of the current status of
|V_ub| determinations. Precision measurements of charmless semileptonic
B-decays allow for a determination of the magnitude of the CKM matrix
element V_ub, for a test of the consistency of the CKM mechanism and
potentially of NP scenarios.
In this talk the various experimental methods to determine |V_ub| based
on...
Chris Bouchard
(University of Illinois)
10/09/2014, 09:45
Recently published and preliminary Fermilab/MILC and HPQCD lattice QCD calculations of form factors for B -> pi l nu and Bs -> K l nu will be presented. In combination with existing experiment, these results generate a significant reduction in the error of Vub. I will also discuss plans to improve the lattice calculations, including the use of a fully relativistic b quark to eliminate...
Mr
Felix Bahr
(DESY Zeuthen)
10/09/2014, 10:05
We present the current status of the ongoing work of the ALPHA collaboration on the computation of the form factor $f_+ (q^2)$ for the semi-leptonic decay $\textnormal B_\textnormal s \to \textnormal K \ell \nu$. We simulate on lattices generated as part of the Coordinated Lattice Simulations (CLS) effort which have $N_\textnormal f=2$ non-perturbatively $O(a)$ improved Wilson fermions that...
Dr
Benoit Blossier
(CNRS/Laboratoire de Physique Théorique d'Orsay)
10/09/2014, 10:25
Understanding the composition of final states in B --> Xc l nu could help
to get a feedback on the persisting disagreement between exclusive and
inclusive determinations of Vcb. In particular the series of orbital
excitations D** and radial excitations (D', D*') has received a lot of
attention; a misinterpretation as a scalar state of the (D' --> D pi)
spectrum tail could have induced an...
Andreas Crivellin
(University Bern)
10/09/2014, 11:35
In this talk I review the flavour phenomenology of two-Higgs-doublet
models with generic Yukawa structure. After discussing the constraints
from FCNC I show that even taking into account these bound, one can still
get sizable effects in B->(D^(*))tau nu. In order to explain the observed
deviations in tauonic B decays from the SM large flavour-changing elements
connecting top and charm are...
Alejandro Celis
(IFIC CSIC-Universitat de Valencia)
10/09/2014, 11:55
I will discuss the status of B to D(*) Tau Nu decays in the context of the aligned two-Higgs-doublet model. The sensitivity of these decays to charged scalar contributions will be considered, taking into account constraints from leptonic meson decays and direct searches for a charged Higgs at colliders. The role of differential distributions to discriminate a charged scalar from other types...
Fulvia De Fazio
(INFN - Sezione di Bari)
10/09/2014, 12:35
The BaBar measurements of the ratios ${\cal R}(D^{(*)})=\frac{{\cal B}(B \to D^{(*)} \tau {\bar \nu}_\tau)}{{\cal B}(B \to D^{(*)} \mu {\bar \nu}_\mu)}$ deviate from the standard model expectation, while new results
on the purely leptonic $B \to \tau {\bar \nu}_\tau$ mode show a better consistency with the standard model, within the uncertainties. In a new physics scenario, one possibility to...
Dr
Matthew Wingate
(University of Cambridge)
11/09/2014, 09:20
We present a brief review of our lattice calculation of $\Lambda_b \to p$ form factors in the static $b$ quark limit. A new calculation using relativistic $b$ quarks is underway and its status will be discussed.
Dr
Nazario Tantalo
(Rome University "Tor Vergata")
11/09/2014, 09:40
In this talk I shall discuss, from a methodological point of view, some of the theoretical and numerical problems that arise in lattice calculations of heavy flavoured hadronic observables. I shall also emphasize the importance of non-perturbative lattice techniques for the calculation of heavy quark masses and give an outlook on the possibility of performing lattice calculations of QED...
Dr
Andrey Tayduganov
(Osaka University)
11/09/2014, 10:05
The observed discrepancy between the experimental results and the
Standard Model prediction for the ratios of the branching fractions of the decays
B-> D(*) tau nu and B-> D(*) mu nu came as a surprise and lead to a discussion of
testing New Physics through these modes. We discuss the possibilities for observing
the New Physics effects by examining the q^2 and the angular distributions of...
Dr
Guglielmo De Nardo
(INFN Napoli)
11/09/2014, 10:25