相关论文: Isospin breaking in the decay constants of heavy m…
QCD sum rules for decay constants of heavy mesons with $u$ or $d$ quark yield for $B$ mesons much less isospin breaking than lattice QCD but good agreement for $D$ mesons.
We explore, by a rather peculiar limit of QCD sum rules subject to a Borel transformation (realized by allowing the related Borel mass parameter to approach infinity), how the small difference of the masses of up and down quark translates…
QCD sum rules are analytic predictions of hadron observables from quantum chromodynamics. In the so-called local-duality limit of their Borel-transformed form, all nonperturbative contributions are encompassed by just a single quantity, an…
Compared with lattice QCD, isospin breaking of heavy-meson decay constants from QCD sum rules agrees for $D$ mesons but disagrees (by a factor of four) for $B$ mesons.
Applying the QCD sum-rule machinery in the so-called local-duality shape to heavy-light mesons reveals that, as a consequence of the non-zero mass gap between up and down quarks, the leptonic decay constants of the neutral and charged…
We sketch a recent sum-rule extraction of the decay constants of the heavy pseudoscalar mesons D, D_s, B, and B_s from the two-point correlator of heavy-light pseudoscalar currents [1]. Our main emphasis lies on the control over all the…
We present a study of the isospin-breaking (IB) corrections to pseudoscalar (PS) meson masses using the gauge configurations produced by the ETM Collaboration with $N_f=2+1+1$ dynamical quarks at three lattice spacings varying from 0.089 to…
We calculate the leptonic decay constants of heavy-light pseudoscalar mesons with charm and bottom quarks in lattice quantum chromodynamics on four-flavor QCD gauge-field configurations with dynamical $u$, $d$, $s$, and $c$ quarks. We…
We discuss the leptonic decay constants of heavy--light mesons by means of Borel QCD sum~rules in the local-duality (LD) limit of infinitely large Borel mass parameter. In this limit, for an appropriate choice of the invariant structures in…
We present a sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents [1]. Our main emphasis is laid on the control over the uncertainties in the decay…
Decay constants of $D$ and $B$ mesons are estimated within the framework of a heavy-quark approach using measured isospin mass splittings in the $D$, $D^*$, and $B$ states to isolate the electromagnetic hyperfine interaction between quarks.…
We compute the vector meson decay constants fD*, fDs* from the simulation of twisted mass QCD on the lattice with Nf = 2 dynamical quarks. When combining their values with the pseudoscalar D(s)-meson decay constants, we were able (i) to…
Exploiting recently proposed novel improvements of the techniques used for extracting from QCD sum rules pivotal hadron characteristics, including their systematic errors, we succeed to achieve a conspicuous agreement of the predictions of…
We determine masses and decay constants of heavy-heavy and heavy-charm pseudoscalar mesons as a function of heavy quark mass using a fully relativistic formalism known as Highly Improved Staggered Quarks for the heavy quark. We are able to…
Isospin symmetry breaking in the quark condensates, $< \bar dd> \not= < \bar uu>$, is a fundamental parameter in both the QCD sum rule studies and the chiral perturbation theory. In this article, we apply the QCD sum rule method to treat…
We revisit the sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents. We use the operator product expansion for this correlator expressed in terms of the…
The isospin mass splittings of the pseudoscalar and vector D and B light-heavy quark system have been calculated using the method of QCD sum rules. Nonperturbative QCD effects are shown to be very small, so that mass splittings arise almost…
We present a sum-rule extraction of heavy-meson decay constants from the two-point correlator of heavy-light pseudoscalar currents. Our main concern is to control the uncertainties of the decay constants, induced by both input QCD…
We describe a recent lattice-QCD calculation of the leptonic decay constants of heavy-light pseudoscalar mesons containing charm and bottom quarks and of the masses of the up, down, strange, charm, and bottom quarks. Results for these…
We revisit QCD sum rules for the decay constants of heavy-light mesons. In the sum rules for the vector mesons B^*_(s) and D^*_(s) we improve the accuracy of OPE, taking into account the O(alpha_s^2) terms in the perturbative part and…