Related papers: A Nonperturbative Study of Quarkonium Systems
Searching for dark matter is a primary goal of modern astronomy and particle physics. Invisible decays of heavy quarkonia are particularly promising for probing light dark matter, attracting broad interest due to their unique sensitivity.…
Within the nonrelativistic QCD (NRQCD) factorization framework, we compute the order-$\alpha_s^3$ perturbative corrections to the leptonic decay of the $\Upsilon$ and $J/\psi$ with high numerical accuracy, at the lowest order in velocity…
We calculate the masses and leptonic decay widths of the bottomonium $b\bar b$ and charmonium $c\bar c$ states in a constituent quark model where the Cornell-like potential and spin-dependent interaction are employed, with all model…
Numerical simulations of the quarkonium spin splittings are done in the framework of lattice nonrelativistic quantum chromodynamics (NRQCD). At leading order in the velocity expansion the spin splittings are of $O(M_Q v^4)$, where $M_Q$ is…
The lattice gauge theory technique for non-perturbative calculations in QCD is reviewed. The extraction of the continuum limit of lattice results is discussed with particular examples appropriate to hadron spectroscopy (the light hadrons…
Lattice calculations of matrix elements relevant for kaon decays, and in particular for epsilon'/epsilon, are reviewed. The role of the strange quark mass is also discussed. A comparison with other non-perturbative approaches used to…
We perform a lattice QCD study of the $\rho$ meson decay from the $N_f=2+1$ full QCD configurations generated with a renormalization group improved gauge action and a non-perturbatively $O(a)$-improved Wilson fermion action. The resonance…
We provide first-principles non-perturbative determinations of the low-lying meson mass spectrum of large-$N$ QCD in the 't Hooft limit $N_{\scriptscriptstyle{\rm f}}/N\to 0$, as well as of three low-energy constants appearing in the QCD…
Following the Non-Relativistic QCD approach we use a gauge invariant smearing method with factorization to measure the excitation energies for a heavy $Q\bar{Q}$ system on a $24^3\times 48$ lattice at $\beta=6.2$. The results come from…
In the NRQCD factorization for productions and decays of a quakonium the difference between the quarkonium mass and the twice of the heavy quark mass is neglected at the leading order of the small velocity expansion. The effect of this…
The proton decay has not been experimentally observed with the lower limit of the proton lifetime being $\gtrsim 10^{34}$ years which is more than the age of the universe. One of the important quantity that appears in the study of the…
Heavy-light mesons, heavy quarkonium and doubly heavy baryons are briefly discussed. Effective field theories (EFTs) of QCD based on the heavy quark mass expansion 1/m_Q provide a unified framework to describe all three systems. They…
In recent years, we used lattice QCD to calculate some quantities that were unknown or poorly known. They are the $q^2$ dependence of the form factor in semileptonic $D\to Kl\nu$ decay, the leptonic decay constants of the $D^+$ and $D_s$…
While neutrino oscillation experiments have demonstrated that neutrinos have small, nonzero masses, much remains unknown about their properties and decay modes. One potential decay mode --- neutrinoless double beta decay ($0 \nu \beta…
A critical appraisal is given of a recent analysis of the quark-mass and finite-size dependence of unquenched lattice QCD data for the nucleon mass. We use this forum to estimate the boundary of the chiral regime for nucleon properties.
The status of lattice calculations of heavy quark phenomenology is reviewed. Particular emphasis is placed on the understanding and control of the calculational uncertainties. The ensuing implications for constraining the CKM matrix…
recently proposed strictly phenomenological static quark-antiquark potential belonging to the generality $V(r)=-Ar^{-\alpha}+\kappa r^{\beta}+V_{0}$ is tested with heavy quarkonia in the context of the shifted large N-expansion method. This…
Recent results on the QCD analysis of bound states of heavy $\bar{q}q$ quarks are reviewed, paying attention to what can be derived from the theory with a reasonable degree of rigour. We report a calculation of $\bar{b}c$ bound states; a…
We present a model-independent calculation of hadron matrix elements for all dimension-six operators associated with baryon number violating processes using lattice QCD. The calculation is performed with the Wilson quark action in the…
Recent data for the masses of $D$ and $D^*$ mesons determined using methods of lattice QCD for several values of the charm quark mass different from its physical mass are analysed in Heavy Quark Effective Theory. Nonperturbative parameters…