相关论文: N Delta - Transition Form Factors at Low Momentum …
The SU(3) breaking effects due to light quark masses on heavy meson masses, decay constants ($F_{D}, F_{D_{s}}$) and the form factor for semileptonic $\overline{B}\rightarrow D^{(\ast)} l\bar{\nu}_{l}$ transitions are formulated in chiral…
We study the $\gamma^\ast \Lambda \to \Sigma^0$ transition form factors by applying the covariant spectator quark model. Using the parametrization for the baryon core wave functions as well as for the pion cloud dressing obtained in a…
A common feature of recent functional renormalization group investigations of effective low-energy QCD is the appearance of a back-bending behavior of the chiral phase transition line at low temperatures together with a negative entropy…
Recent calculations of EDMs of light nuclei in the framework of chiral effective field theory are presented. We argue that they can be written in terms of the leading six low-energy constants encoding CP-violating physics. EDMs of the…
Experimental observables of the elastic eD-scattering in the region of intermediate energies are discussed. We offer the analysis of the available experimental data, which reproduces the results of the calculations with popular…
We develop techniques to calculate the four Delta electromagnetic form factors using lattice QCD, with particular emphasis on the sub-dominant electric quadrupole form factor that probes deformation of the Delta. Results are presented for…
We present the Non-Relativistic QCD (NRQCD) calculations at the next-to-leading order (NLO) of $\alpha_s$ for $B_c^*\to \eta_c$ vector, axial-vector, tensor and axial-tensor form factors, and obtain complete analytical expressions for the…
Within the Dyson-Schwinger equation approach to modeling QCD for meson physics, we present new results for $g_{\rho\pi\pi}$ and the coupling constants and form factors for the transitions $\gamma^\ast \pi \rho$ and $\gamma^\ast \pi^0…
We analyse various $U(1)_{EM}$ form factors of mesons at strong coupling in an $\mathcal{N}=2$ flavored version of $\mathcal{N}=4$ $SYM$ which becomes conformal in the UV. The quark mass breaks the conformal symmetry in the IR and generates…
Radiative transitions gamma + Delta(1232) -> N^* are discussed in the nonrelativistic quark model with spin-orbit corrections for the 70-plet L^P=1^- nucleon resonances N^*. The reaction gamma + N -> gamma + Delta is considered as a tool to…
The off-shell electromagnetic vertex of a (pseudo-) scalar particle contains, in general, two form factors F and G which depend, in addition to the squared momentum transfer, on the invariant masses associated with the initial and final…
Electro magnetic transition form factors for the excitation of the Delta33-resonance are evaluated in the Skyrme model. They crucially rely on rotationally induced deformations of the hedgehog soliton which are suppressed by two N_C-orders…
The magnetic-dipole form factor and the ratios R_EM and R_SM for the gamma* N -> Delta(1232)3/2}+ transition are predicted within light-front relativistic quark model up to photon virtuality Q2=12 GeV2. We also predict the helicity…
The form factors, as well as the helicity amplitudes for the $\gamma^\ast N \to N(1535)$ transition are calculated in framework of the QCD light cone sum rules. The contamination coming from diagonal transition is eliminated by considering…
Experimental form factors of the hydrogen and helium isotopes, extracted from an up-to-date global analysis of cross sections and polarization observables measured in elastic electron scattering from these systems, are compared to…
We calculate the momentum dependence of three particle vertices $\sigma \gamma \gamma$, $\sigma \rho \gamma$ and $\sigma \rho \rho$ in the context of a Nambu Jona Lasinio type model. We show how they influence the processes $\gamma \gamma…
The covariant spectator quark model is applied to the $\gamma^\ast N \to N^\ast(1520)$ reaction. The valence quark contributions to the electromagnetic form factors and helicity transition amplitudes are estimated from the covariant…
We investigate the axial-vector transition form factors of the baryon octet to the baryon decuplet within the framework of the chiral quark-soliton model, with the effects of flavor SU(3) symmetry breaking included. We consider the…
Weak $B^-\rightarrow D^0, \pi^0$ and $D^-\rightarrow {K}^0, \pi^0$ transition form factors are described in both the space- and time-like momentum transfer regions, within a constituent-quark model. Neutrino-meson scattering and…
The form factor $g_{\rho \pi}^{(S)}(Q^{2})$ of the strange vector current transition matrix element $<\rho| \bar{s}\gamma_\mus|\pi>$ is calculated within the chiral quark model. A strange vector current of the constituent $U$- and D-quarks…