Related papers: Upper bounds on $f_D$ and $f_{D_s}$ from two-point…
We present results for the B_s meson decay constant f_{B_s} from simulations at three lattice spacings in the range a^{-1}=1.1 to 2.6 GeV using NRQCD heavy quarks and clover light quarks in the quenched approximation. We study scaling of…
Using CLEO data collected at 3370 MeV and 4170 MeV, we determine fD = (205.8 +- 8.5 +- 2.5) MeV and an interim preliminary value of fDs = (267.9 +- 8.2 +- 3.9) MeV, where both results are radiatively corrected. They agree with the recent…
The goal of this thesis is to calculate properties of D-Mesons with QCD-Sum-Rules in order to understand the nature of D-Mesons with positive parity. The result is that such D-Mesons most probably are Mesons with a four quark rather than a…
Meson Green's functions and decay constants $f_{\Gamma}$ in different channels $\Gamma$ are calculated using the Field Correlator Method. Both, spectrum and $f_\Gamma$, appear to be expressed only through universal constants: the string…
The masses and decay constants of pseudoscalar mesons $ D $, $ D_s $, and $ K $ are determined in quenched lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with single-plaquette action at $ \beta = 6.1 $ on the…
In this article, we recalculate the contributions of all vacuum condensates up to dimension-6, in particular the one-loop corrections to the quark condensates $\alpha_s<\bar{q}q>$ and partial one-loop corrections to the four-quark…
We present a precise determination of the leptonic decay constant F_D(s) of the D(s)-meson in quenched lattice QCD. This work is particularly focused on the analysis and discussion of all sources of systematic errors. We simulate directly…
We improve a previous quenched result for heavy-light pseudoscalar meson decay constants with the light quark taken to be the strange quark. A finer lattice resolution (a ~ 0.05 fm) in the continuum limit extrapolation of the data computed…
We present a lattice determination of the leptonic decay constant F_Ds of the Ds-meson using its mass and F_K as experimental input. Setting the scale with F_K=160 MeV, our final result is F_Ds = 252(9) MeV. The error contains all…
We have calculated the decay constants of B and $D$ mesons with lattice QCD. We use an $O(a)$ improved action that takes light quark actions as a starting point, tuned so that it can be directly applied at the physical masses of the $b$ and…
We determine $D$ and $D_s$ decay constants from lattice QCD with 2% errors, 4 times better than experiment and previous theory: $f_{D_s}$ = 241(3) MeV, $f_D$ = 207(4) MeV and $f_{D_s}/f_D$ = 1.164(11). We also obtain $f_K/f_{\pi}$ =…
The coupling constant of the meson vertex $J/\psi D_s D_s$ is calculated using the three point correlation function within the QCD Sum Rule formalism. We have considered alternately mesons $J/\psi$ and $D_s$ off-shell together with…
We evaluate equal time point to point spatial correlation functions of mesonic currents at finite temperature. For this purpose we consider the QCD vacuum structure in terms of quark antiquark condensates and their fluctuations in terms of…
We review recent progress in the calculation of the decay constants $f_{D}$ and $f_{D_s}$ from lattice QCD. We focus particularly on simulations with $N_f=2+1$ and $N_f=2+1+1$ and simulations with close to physical light quark masses.
We use an appropriate combination of moments of finite energy sum rules in QCD in order to compute the B_q-meson decays constants f_B and f_{B_s}.We perform the calculation using a two-loop computation of the imaginary part of the…
We calculate charmed meson spectra and decay constants in lattice QCD employing one-loop $O(a)$ improved heavy quark action and axial-vector currents. In quenched simulations at $a \sim 0.1$ fm with the plaquette gauge action as well as a…
Decay constants of pseudoscalar mesons $D$, $D_s$, $\eta_c$ and vector mesons $D^*$, $D_s^*$, $J/\psi$ are determined from $N_f=2+1$ lattice QCD at a lattice spacing $a\sim0.08$ fm. For vector mesons, the decay constants defined by tensor…
Equal time, point to point correlation functions for spatially separated meson currents are calculated with respect to a variational construct for the ground state of QCD. With exact calculations, vector, axial vector and scalar channels…
The mass spectra of $D_s$ meson is obtained in the framework of relativistic independent quark model using Martin like potential for the quark confinement. The predicted excited states are in good agreement with the experimental results as…
We show that in the context of QCD sum rules a strong (anti-) correlation between the $b$-quark mass $m_b$ and the $B$-meson's decay constant $f_B$ emerges: $\delta f_B/f_B\approx -8 \delta m_b/m_b.$ This observation allows us to derive a…