Related papers: Resummed pole mass, static potential, and Upsilon(…
Using the recent {\it world average} $\alpha_s(M^2_Z)= 0.118 \pm 0.006$, we give the {\it first direct extraction} from the $\Psi$ and $\Upsilon$ data of the values of the {\it running heavy quark masses} within QCD spectral sum rules to…
We present new results on $\Upsilon$ and $J/\Psi$ spectroscopy using Lattice NRQCD. Charmonium results at quenched $\beta$ = 5.7 show agreement with experiment within understood systematic errors. We compare bottomonium results at quenched…
Taylor expansion in powers of baryon chemical potential ($\mu_B$) is an oft-used method in lattice QCD to compute QCD thermodynamics for $\mu_B>0$. Based only upon the few known lowest order Taylor coefficients, it is difficult to discern…
The bottomonium spectrum is the perfect testing ground for the confining potential and unitarisation effects. The bottom quark is about three times heavier than the charm quark, so that $b\bar{b}$ systems probe primarily the short-range…
We calculate the mass difference between the $\Upsilon$ and $\eta_b$ and the $\Upsilon$ leptonic width from lattice QCD using the Highly Improved Staggered Quark formalism for the $b$ quark and including $u$, $d$, $s$ and $c$ quarks in the…
The perturbatively calculable short distance QCD potential is known to two loops including the effect of massive quarks. Recently, a simple approximate solution in momentum space was utilized to obtain the potential in coordinate space. The…
We investigate the $u=1/2$ [$\mathcal{O}(\Lambda_{\rm QCD})$] and $u=3/2$ [$\mathcal{O}(\Lambda_{\rm QCD}^3)$] renormalons in the static QCD potential in position space and momentum space using the OPE of the potential-NRQCD effective field…
We reanalyze the perturbative QCD (pQCD) corrections to quarkonium QCD sum rules and extract the heavy quark masses $\overline{m}_{q}(\overline{m}_{q})$ ($q=c,b$). At present, the pQCD corrections to the correlation functions of two…
A method is presented which allows for the renormalization of the self-potential for a scalar point charge at rest in static curved space-time. The method is suitable for the scalar field with arbitrary mass $m$ and coupling to the scalar…
Effects associated with hyperfine mass splitting between pseudo\-scalar and vector mesons may induce surprisingly large $1/{m}_{Q}^{2}$ corrections in the heavy quark expansion. We demonstrate this in a relativistic quark model by…
We have calculated the next-to-leading order perturbative QCD corrections to the photon energy spectrum in radiative Upsilon decays. The higher-order corrections significantly modify the shape of the spectrum, in particular at large photon…
We investigate the spectrum of $T_{\Upsilon\Upsilon}$ tetraquark candidates within a coupled-channels framework. The analysis includes all $L\leq2$ combinations of $\Upsilon(1S)$, $\Upsilon(2S)$, $\eta_b(1S)$, and $\eta_b(2S)$ in the $J^P =…
Recent calculations of heavy quark cross sections near threshold at next-to-next-to-leading order have found second-order corrections as large as first-order ones. We analyse long-distance contributions to the heavy quark potential in…
We present results for higher order perturbative corrections to Compton scattering in the generalized Bjorken kinematics. The approach we have used is based on the combination of two techniques: conformal operator product expansion on the…
We analyze the heavy quark bound state spectrum using an order-dependent conformal mapping to re-sum the perturbative expansion for current correlators. The procedure consists of two main steps. Firstly, the Borel plane structure of the…
We compute the heavy quarkonium mass of $l\not= 0$ (angular momentum) states, with otherwise arbitrary quantum numbers, with next-next-to-next-to-leading logarithmic (N$^3$LL) accuracy. This constitutes the first observable in heavy…
We compute the electric dipole transitions $\chi_{bJ}(1P)\to \gamma\Upsilon(1S)$, with $J=0,1,2$, and $h_{b}(1P)\to \gamma\eta_{b}(1S)$ in a model-independent way. We use potential non-relativistic QCD (pNRQCD) at weak coupling with either…
From a fit to the experimental data on the $b\bar{b}$ fine structure, the two-loop coupling constant is extracted. For the 1P state the fitted value is $\alpha_s(\mu_1) = 0.33 \pm 0.01(exp)\pm 0.02 (th)$ at the scale $\mu_1 = 1.8 \pm 0.1$…
Following the nonrelativistic QCD factorization scheme, by taking latest available measurement on $\chi_b(3P)$ into consideration, we present an updated study on the yield and polarization of $\Upsilon(1S,2S,3S)$ hadroproduction, and the…
It had been known that the Borel transforms of the twice quark pole mass 2*mq and of the QCD q-barq static potential V(r) have leading infrared renormalons at b=1/2 such that they cancel in the sum. The renormalon residue of 2*mq had been…