Related papers: Light scalar mesons in D^+, D_s^+ decays into thre…
Masses of the ground state light tetraquarks are dynamically calculated in the framework of the relativistic diquark-antidiquark picture. The internal structure of the diquark is taken into account by calculating the form factor of the…
The potentiality of interpreting the D-meson decay-dynamics has revealed itself to be strongly dependent on our understanding of the light-meson sector. The statistics collected by FOCUS is already at a level that manifests parametrization…
Based on the predictions of the relevant form factors from the covariant light-front quark model, we show the branching fractions for the $D (D_s) \to (P,\,S,\,V,\,A)\,\ell\nu_\ell$ ($\ell=e$ or $\mu$) decays, where $P$ denotes the…
The features of a model interpreting the light scalar mesons as diquark-antidiquark bound states and the consequences of its natural extension to include heavy quarks are briefly reviewed.
Scalar mesons are a key expression of the strong physics regime of QCD and the role condensates, particularly $<q{\bar q}>$, play in breaking chiral symmetry. What new insights have been provided by recent experiments on $D, D_s$ and…
The hadronic charmless B decays into a scalar meson and a pseudoscalar meson are studied within the framework of QCD factorization. Although the light scalar mesons $f_0(980)$ and $a_0(980)$ are widely perceived as primarily the four-quark…
Light scalar mesons abound in hadron processes, like the alligators in the Florida Everglades. Moreover, scalars are intimately tied to the vacuum structure of QCD. They are the product of many decays. Consequently, a rich source of recent…
We review here the physics of purely leptonic decays of pi-, K-, D+, Ds+, and B- pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak interaction based CKM matrix element of the constituent quarks…
We present a theoretical framework that accounts for the new $D_J$ and $D_{sJ}$ mesons measured in the open-charm sector. These resonances are properly described if considered as a mixture of conventional $P-$wave quark-antiquark states and…
We investigate the phenomenology of scalar diquarks with sub-TeV masses within the framework of the $E_6$ Supersymmetric Standard Model (E$_6$SSM) at the Large Hadron Collider (LHC). Focusing on the lightest of the six diquarks predicted by…
A brief overview of charm scalar resonances is given. It is demonstrated that experimental data on the D_s^{*+}gamma and D_s^+pi^0 decays of D_{s0}^+(2317) favor its assignment to the I_3=0 component of iso-triplet four-quark mesons. The…
We study the light scalar mesons in the QCD sum rule. We find that there are five independent scalar tetraquark currents in the local form, and we perform QCD sum rule analysis using both these currents and their combinations. Compared with…
B mesons are bound states of a b quark and a light anti-quark. While the binding is provided by the strong interaction B mesons can only decay by the weak interaction. Since the top quark mass is large, B mesons are the only mesons…
Exotic mesons with hidden strange ($s\bar s$) and heavy quark pairs ($Q\bar Q$), where $Q=c,b$, are considered as diquark-antidiquark systems, $(Qs)(\bar Q\bar s)$. Taking into account that these states can recombinate into two-meson ones,…
We study the lowest-lying scalar mesons in the QCD sum rule by considering them as tetraquark states. We find that there are five independent currents for each state with a certain flavor structure. By forming linear combinations, we find…
The ${q}\bar{q}$ spectrum is studied within a chiral constituent quark model. It provides with a good fit of the available experimental data from light (vector and pseudoscalar) to heavy mesons including some recent results on charmonium.…
We study the spectra of the doubly charmed tetraquark states in a diquark-antidiquark model. The doubly charmed tetraquark states form an antitriplet and a sextet configurations according to flavor SU(3) symmetry. For the tetraquark state…
Within our description of Goldstone-type pseudoscalar mesons as almost massless bound states of quark and antiquark by a three-dimensional bound-state equation of Bethe-Salpeter origin, taking into account the pointwise behaviour of the…
We adopt the heavy baryon chiral perturbation theory (HBChPT) to calculate the scattering lengths of $\phi B_{cc}^{(*)}$ up to $\mathcal{O}(p^3)$, where $\phi$ is the pseudoscalar mesons. The recoil effect and the mass splitting between the…
Within the framework of covariant confined quark model, we compute the transition form factors of $D$ and $D_s$ mesons decaying to light scalar mesons $f_0(980)$ and $a_0(980)$. The transition form factors are then utilized to compute the…