相关论文: Kaon form factor in holographic QCD

We present first results from the QCDSF collaboration for the kaon semileptonic decay form factors at zero momentum transfer, using two flavours of non-perturbatively O(a)-improved Wilson quarks. A lattice determination of these form…

We present a formula that allows one to calculate the pion form factor in the timelike region 2mpi <= sqrt{s} <= 4mpi in lattice QCD. The form factor quantifies the contribution of two-pion states to the vacuum polarization. It must be…

It has been previously shown that a particular nonperturbative constituent-quark model of hadrons describes experimental measurements of electromagnetic form factors of light charged mesons through a small number of common phenomenological…

We review the present situation with hadron form factors in space-like and time-like regions. The possibility to transfer high momenta, and therefore to access small internal nucleon distances, allows to test nucleon models in particular…

The recently measured $\gamma\gamma^*\rightarrow \pi^0$ anomalous form factor is analyzed using the $D4/D8\bar{D8}$ holographic approach to QCD. The half-on-shell transition form factor is vector meson dominated and is shown to exactly tie…

We present a preliminary result of the kaon semileptonic form factor calculated at the smallest lattice spacing in the PACS10 configurations, whose physical volumes are more than (10 fm)$^4$ at the physical point. The configurations were…

We present a lattice QCD calculation of the electric polarizability of the charged kaon using a four-point function approach, which is the Euclidean analog of low-energy Compton scattering. In the case of the charged kaon, the…

We study the pion form factor in a broad range of spacelike momentum transfers within the local-duality version of QCD sum rules. We make use of the recently calculated two-loop double spectral density of the $<AVA>$ correlator including…

We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$ mesons to light pseudoscalar and vector mesons within a relativistic dispersion approach based on the constituent quark picture. This approach gives the form factors…

We study the anomalous electromagnetic pion form factor $F_{\pi^0\gamma^*\gamma^*}$ with a set of holographic models. By comparing with the measured value of the linear slope, some of these models can be ruled out. From the remaining models…

Elastic and semileptonic transition form factors for the kaon and pion are calculated using the leading-order in a global-symmetry-preserving truncation of the Dyson-Schwinger equations and a momentum-independent form for the associated…

A novel method is employed to compute the pion electromagnetic form factor, F_\pi(Q^2), on the entire domain of spacelike momentum transfer using the Dyson-Schwinger equation (DSE) framework in quantum chromodynamics (QCD). The DSE…

We calculate the kaon semileptonic form factors in lattice QCD with three flavors of dynamical overlap quarks. Gauge ensembles are generated at pion masses as low as 290 MeV and at a strange quark mass near its physical value. We precisely…

There has been considerable progress in the study of the electromagnetic form factors of baryons in the timelike region, through electron-positron scattering reactions ($e^+ e^- \to B \bar B$), in the last two decades. Timelike experiments…

Even though quantum chromodynamics is a broken conformal theory, the AdS/CFT correspondence has led to important insights into the properties of QCD. For example, as shown by Polchinski and Strassler, dimensional counting rules for the…

We present an outline of recent developments in the field of hadron form-factor calculations within constituent-quark models using the point form of relativistic quantum mechanics. Our method to calculate currents and form factors is…

The form factors of the semileptonic $B$, $B_s$ and $B_c$ meson decays are calculated in the framework of the relativistic quark model based on the quasipotential approach in QCD. They are expressed through the overlap integrals of the…

The CKM matrix element $|V_{us}|$ can be extracted from the experimental measurement of semileptonic $K\to\pi$ decays. The determination depends on theory input for the corresponding vector form factor in QCD. We present a preliminary…

The QCD evolution of the pion distribution amplitude (DA) $\phi_\pi(x,Q^2)$ is computed for several commonly used models. Our analysis includes the nonperturbative form predicted by light-front holographic QCD, thus combining the…

We consider the pion structure in the region of low and moderately high momentum transfers: at low $Q^2$, the pion is treated as a composite system of constituent quarks; at moderately high momentum transfers, $Q^2=10\div25\;GeV^2$, the…