相关论文: Electroweak Penguins and Large Nc
We will report on the status of a new large scale calculation of thermodynamic quantities in QCD with light up and down quarks corresponding to an almost physical light quark mass value and a heavier strange quark mass. These calculations…
We present a new independent evaluation of the hadronic and QCD contributions to the QED running coupling \alpha(M_Z) and to the muonium hyperfine splitting \nu. We obtain: \Delta\alpha_{had}=2770(17)10^{-5} and \Delta\nu_{had}=232.5(2.5)…
A review of methods to extract the standard CKM unitarity triangle angle alpha is provided. The sizes of related theoretical errors are reviewed.
Latest experimental progress is reviewed on the searches for physics beyond the Standard Model using the radiative and electroweak penguin decays of B mesons. This review covers inclusive and exclusive measurements of the b --> s gamma, b…
We report measurements of Time-Dependent CP asymmetries in several $b\to s$ penguin dominated hadronic B decays, where New Physics contributions may appear. We find no significant discrepancies with respect to the Standard Model…
The broad progress in QCD studies during the last years is summarised
Though QCD Factorization(QCDF) could produce sufficiently large $B\to K\pi$ branching ratios close to experiments, the predicted direct CP asymmetry in ${\bar B}^{0}\to K^{+}\pi^{-}$ decay is however still quite below experiment, even with…
We present an analytical calculation of the two-loop QCD corrections to the electromagnetic form factor of heavy quarks. The two-loop contributions to the form factor are reduced to linear combinations of master integrals, which are…
I review the status of lattice QCD calculations of the hadronic contributions to the muon's anomalous magnetic moment, focussing on the hadronic vacuum polarisation contribution which dominates the uncertainty of the Standard Model…
We study QCD in 2 dimensions using the improved lattice fermionic Hamiltonian proposed by Luo, Chen, Xu and Jiang. The vector mass and the chiral condensate are computed for various $SU(N_C)$ gauge groups. We do observe considerable…
We introduce a model independent method for the determination of the hadronic contribution to the QED running coupling, $\Delta\alpha_{\text{HAD}}(M_{Z}^{2})$, requiring no $e^+e^-$ annihilation data as input. This is achieved by…
We evaluate the decays B => K* pi, K (rho,omega,phi) adding the long distance charming penguin contributions to the short distance: Tree+Penguin amplitudes. We estimate the imaginary part of the charming penguin by an effective field theory…
The $B\to \pi\pi$ hadronic matrix element of the chromomagnetic dipole operator $O_{8g}$ (gluonic penguin) is calculated using the QCD light-cone sum rule approach. The resulting sum rule for $<\pi\pi |O_{8g}|B>$ contains, in addition to…
We have considered the penguin interaction contribution to $K \rightarrow 2 \pi$ decays. In particular, we have investigated the effect of the momentum dependence of the penguin coefficient. Our analysis is performed within the Chiral Quark…
We present new contributions to the decay matrix element $\Gamma_{12}^q$ of the $B_q$-$\bar B_q$ mixing complex, where $q=d$ or $s$. Our new results constitute the order $\alpha_s^2 N_f$ corrections to the penguin contributions to the…
I review recent progress on algorithms for calculating quark propagators and for simulating full QCD.
We present an analysis of two-loop mixed QCD and electroweak corrections to the decay of the Z boson into light quarks. We find that the naive factorization of QCD and electroweak corrections does not describe correctly the two-loop…
We construct an improved version of nonrelativistic QCD for use in lattice simulations of heavy quark physics, with the goal of reducing systematic errors from all sources to below 10\%. We develop power counting rules to assess the…
We perform a fit to the 2006 B -> pi K data and show that there is a disagreement with the standard model. That is, the B -> pi K puzzle is still present. In fact, it has gotten worse than in earlier years. Assuming that one new-physics…
This document is one of a series of whitepapers from the USQCD collaboration. Here, we discuss opportunities for lattice QCD calculations related to the structure and spectroscopy of hadrons and nuclei. An overview of recent lattice…