Related papers: On the spectral functions of scalar mesons
The enhancement of the scalar-isoscalar spectral function near the two-pion threshold is studied in the framework of an effective linear $\sigma$ model, using a large N approximation in the number of the Goldstone bosons. The effect is…
The generalized linear sigma model for mixing among two- and four-quark components of scalar (and psedudosclar) mesons below and above 1 GeV is applied to the $\pi\eta$ channel in which the isovector scalars $a_0(980)$ and $a_0(1450)$ are…
This paper discusses the simplest examples of spectral zeta functions, especially those associated with graphs, a subject which has not been much studied. The analogy and the similar structure of these functions, such as their parallel…
Dispersion relations---a corollary of unitarity and analyticity---are among the few methods which can be employed to study low energy processes in QCD. In this work we critically revisit the calculation of decay widths of a hypothetical…
In this work we study the spatial-momentum dependence of mesonic spectral functions obtained from the quark-meson model using a recently proposed method to calculate real-time observables at finite temperature and density from the…
We discuss the non-relativistic multichannel quark model and describe the techniques developed to solve the resulting equations. We then investigate some simple solutions to demonstrate how the model unifies meson-meson scattering with…
We show that $\phi$ radiative decays into scalar mesons [$f_0$(975), $a_0$(980)$\equiv S$] can provide important clues on the internal structures of these mesons. Radiative decay widths vary widely: $B.R.=10^{-4}-10^{-6}$ depending on the…
We determine the mass and strength of the scalar meson from NN scattering data by renormalizing the One Boson Exchange Potential. This procedure provides a great insensitivity to the unknown short distance interaction making the vector…
We study the spectrum of scalar mesons in the holographic dual of walking technicolor, obtained by embedding D7 - anti-D7 probe branes in a certain type IIB background. The scalar mesons arise from fluctuations of the probe techniflavour…
We evaluate lower bounds on the sum of the up and down quark masses. The bounds follow from the constraints provided by the dispersion relation obeyed by the two--point function of the scalar current density when combined with properties of…
We develop a non-perturbative functional framework for computing real-time correlation functions in strongly correlated systems. The framework is based on the spectral representation of correlation functions and dimensional regularisation.…
The decay $\tau^{-}\to K^{-}K_S\nu_{\tau}$ has been studied using $430\times10^6$ $e^+e^-\to \tau^+\tau^-$ events produced at a center-of-mass energy around 10.6 GeV at the PEP-II collider and studied with the BABAR detector. The mass…
Both the mass spectra and the wave functions of the light pseudoscalar ($\pi,K,\eta,\eta'$) and vector($\rho,K^{*},\omega,\phi$) mesons are analyzed within the framework of the light-cone constituent quark model. A gaussian radial wave…
We analyze the quark spectral function above the critical temperature for deconfinement in quenched lattice QCD using clover improved Wilson fermions in Landau gauge. We show that the temporal quark correlator is well reproduced by a…
We analyze the spectral properties of the quark propagator above the critical temperature for the deconfinement phase transition in quenched lattice QCD using clover improved Wilson fermions. The bare quark mass dependence of the quark…
We present a viable method to obtain real-time quantities such as spectral functions or transport coefficients at finite temperature and density within a non-perturbative Functional Renormalization Group approach. Our method is based on a…
In this paper we visited mass spectra and decay constants of pseudoscalar and vector heavy-light mesons ($B$, $B_s$, $D$ and $D_S$) in the framework of QCD sum rule and quark model. The harmonic oscillator wave function was used in quark…
A separable potential model of three coupled channels (pion-pion, kaon-antikaon and an effective four pion) has been constructed and applied in the analysis of the isoscalar S-wave pion-pion and kaon-antikaon phase shifts and inelasticities…
A coupled-channel analysis of BESIII data on radiative $J/\psi$ decays into $\pi\pi$, $K\bar K$, $\eta\eta$ and $\omega\phi$ has been performed. The partial-wave amplitude is constrained by a large number of further data. The analysis finds…
Within a multicomponent dark matter scenario, novel gamma-ray signals may arise from the decay of the heavier dark matter component into the lighter. For a scalar dark sector of this kind, the decay $\phi_2\rightarrow\phi_1 \gamma$ is…