Related papers: Bottomonium Decay Matrix Elements from Lattice QCD…
We investigate the properties of S-and P-wave bottomonium states in the vicinity of the deconfinement transition temperature. The light degrees of freedom are represented by dynamical lattice QCD configurations of the HotQCD collaboration…
We study the temperature dependence of bottomonium for temperatures in the range $0.4 T_c < T < 2.1 T_c$, using nonrelativistic dynamics for the bottom quark and full relativistic lattice QCD simulations for $N_f=2$ light flavors on a…
I review recent developments in lattice weak matrix element calculations. I focus on on $f_B$ (both with propagating quarks and in the static limit for the $b$ quark), semi-leptonic form factors for $D$ meson decay, form factors for $B \to…
We study the light-quark mass and spatial volume dependence of the matrix elements of $\Delta B=0$ four-quark operators relevant for the determination of $V_{ub}$ and the lifetime ratios of single-$b$ hadrons. To this end, one-loop diagrams…
We show how string breaking on the lattice, treated as a mixing effect, can be related to decay rates for heavy quark systems. We use this to make a preliminary calculation of the energy split at maximum mixing for static quarks in QCD from…
We present a lattice-QCD calculation of the $B\to\pi\ell\nu$ semileptonic form factors and a new determination of the CKM matrix element $|V_{ub}|$. We use the MILC asqtad 2+1-flavor lattice configurations at four lattice spacings and…
We review many lattice QCD calculations that impact the precise determination of the CKM matrix. We focus on decay constants and semileptonic form factors of both light ($\pi$ and K) and heavy-light ($D_{(s)}$ and $B_{(s)}$) mesons.…
The leading electromagnetic (e.m.) and strong isospin-breaking corrections to the $\pi^+ \to \mu^+ \nu[\gamma]$ and $K^+ \to \mu^+ \nu[\gamma]$ leptonic decay rates are evaluated for the first time on the lattice. The results are obtained…
We study bottomonium spectral functions in the quark-gluon plasma in the Upsilon and eta_b channels, using lattice QCD simulations with two flavours of light quark on highly anisotropic lattices. The bottom quark is treated with…
The HPQCD collaboration has used radiatively-improved NonRelativistic QCD (NRQCD) for $b$ quarks in bottomonium to determine the decay rate of $\Upsilon$ and $\Upsilon^\prime$ mesons to leptons in lattice QCD. Using time-moments of vector…
We present the results of our lattice QCD study of the hadronic matrix elements relevant to the physical radiative $J/\psi\to \eta_c\gamma$ and $h_c\to \eta_c\gamma$ decays. We used the twisted mass QCD action with $N_{\rm f}=2$ light…
During the last years, the ALPHA collaboration has been developing and implementing a method based on Heavy Quark Effective Theory (HQET) to compute B-mesons observables through lattice simulations. Thanks to a non-perturbative matching to…
We present an improved result of lattice computation of the proton decay matrix elements in $N_f=2+1$ QCD. In this study, the significant improvement of statistical accuracy by adopting the error reduction technique of All-mode-averaging,…
We present an exploratory lattice study of $B\to\pi$ semileptonic decay form factors using the nonrelativistic lattice QCD for heavy quark with Wilson light quark on a $16^3 \times 32$ quenched lattice at $\beta=5.8$. The matrix elements…
We present a lattice-QCD determination of the $\Lambda \to p$ vector and axial-vector form factors, providing theoretical input for studies of the semileptonic decay $\Lambda \to p\ell\bar{\nu}_\ell$. The calculation is carried out on a…
The first lattice QCD calculation of the form factors governing $\Lambda_c \to \Lambda \ell^+ \nu_\ell$ decays is reported. The calculation was performed with two different lattice spacings and includes one ensemble with a pion mass of…
We compute the leptonic decay constants of heavy-light vector mesons in the quenched approximation. The reliability of lattice computations for heavy quarks is checked by comparing the ratio of vector to pseudoscalar decay constant with the…
Precise lattice QCD results for hadronic matrix elements, decay constants and form factors play a crucial role in the determination of CKM matrix elements and in the identification of possible new physics contributions to flavour violating…
We presents results for the matrix elements of a variety of four-fermion operators calculated using quenched Wilson fermions. Our simulations are done on 170 lattices of size $32^3 x 64$ at $\beta = 6.0$. We find $B_K=0.74 +- 0.04 +- 0.05$,…
We report evidence for the ground state of bottomonium, eta_b(1S), in the radiative decay Upsilon(3S) --> gamma eta_b in e^+e^- annihilation data taken with the CLEO III detector. Using 6 million Upsilon(3S) decays, and assuming…