Related papers: Resonance $X(5568)$ as an exotic axial-vector stat…
The masses, current couplings and widths of the fully heavy scalar tetraquarks $X_{\mathrm{4Q}}=QQ\overline{Q}\overline{Q}$, $Q=c, b$ are calculated by modeling them as four-quark systems composed of axial-vector diquark and antidiquark.…
In this work, we use the QCD sum rule method to study the radiative decays of the vector and axial-vector $B_c$ mesons to each of three charmed strange mesons, $D_s$, $D^*_s$ and $D_{s1}$, through their dominant weak annihilation channels.…
In this article, we study the vector and axialvector $B_c$ mesons with the QCD sum rules, and make reasonable predictions for the masses and decay constants, then calculate the leptonic decay widths. The present predictions for the masses…
We present a precise lattice QCD determination of the b-quark mass, of the B and Bs decay constants and first results for the B-meson bag parameters. For our computation we employ the so-called ratio method and our results benefit from the…
The mass and decay constant of the heavy quarkonia $h_{Q}(1P)$ and $h_{Q}(2P)$ (Q = b, c) with quantum numbers $J^{PC} =1^{+-}$ are calculated in the framework of the two-point QCD sum rule method by taking into account the vacuum…
A model of hybrid meson structure based on the QCD Hamiltonian in Coulomb gauge and the use of a single constituent quasigluon is applied compute hadronic decays of mesons with exotic quantum numbers, $0^{+-}$ and $2^{+-}$. These correspond…
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…
In the covariant light-front quark model, we calculate the form factors of $B_c^-\to J/\psi$ and $B_c^-\to X(3872)$. Since the factorization of the exclusive processes $B_c^- \to J/\psi\pi^-(K^-)$ and $B_c^- \to X(3872)\pi^-(K^-)$ can be…
We calculate the complete form of the dimension-8 condensate contributions in the two-point correlator of the ($1^{-+}$,$0^{++}$) light hybrid current considering the operator mixing under renormalization. We find the inclusion these higher…
The strong coupling constant g$_{h_{b}B_{c}^{PS}B_{c}^{V}}$ is calculated using the three-point QCD sum rules method. We use correlation functions to obtain these strong coupling constants with contributions of both B$_{c}^{PS} $ and…
The mass and coupling of the axial-vector tetraquark $T_{bc;\bar{u}\bar{d} }^{0}$ (in a short form $T_{bc}^{0}$) are calculated by means of the QCD two-point sum rule method. In computations we take into account contributions arising from…
The radiative decays $ B^{*} (D^{*})\to B(D) \gamma$ are investigated in the framework of light cone QCD sum rules. The transition amplitude and decay rates are estimated.It is shown that our results on branching ratios of D meson decays…
The strong decays of the pseudoscalar and scalar double-charmed tetraquarks $ T_{cc;\overline{u}\overline{d}}^{+}$ and $\widetilde{T}_{cc;\overline{u} \overline{d}}^{+}$ are investigated in the framework of the QCD sum rule method. The mass…
We summarize recently improved results for the pseudoscalar [1,2] and vector [3] meson decay constants and their ratios from QCD spectral sum rules where N2LO + estimate of the N3LO PT and power corrections up to d< 6 dimensions have been…
The spectroscopic parameters and partial decay widths of the light mesons $ a_0(980) $ and $K_{0}^{\ast}(800)$ are calculated by treating them as scalar diquark-antidiquark states. The masses and couplings of the mesons are found in the…
The full version of QCD light-cone sum rule method is applied to tetraquarks containing a single heavy $b$ or $c$ quark. To this end, investigations of the strong vertices $X_{b}X_{b}\rho$ and $X_{c}X_{c}\rho$ are performed, where…
We employ the $B\to\pi$ form factors obtained from QCD light-cone sum rules and calculate the $B\to \pi \ell \nu_l$ width ($\ell=e,\mu$) in units of $1/|V_{ub}|^2$, integrated over the region of accessible momentum transfers, $0\leq q^2\leq…
New spectroscopy from the B factories, the advent of CLEO-c and the BES upgrade renewed the interest in charmonia. Among the new measurements, the state X(3872) has received special attention due to its unexpected properties. Its structure…
The rare radiative decay $\Xi^{*}_{bb}\to\Xi_b\gamma$ is investigated within the light cone QCD sum rules approach. This decay proceeds through the flavor changing neutral current $b\to s$ transition in the Standard Model. The hadronic…
We discuss the form factors of the heavy-to-light transitions $B \ra \pi$ and $D\ra \pi$, the $B^*B \pi$ and $D^*D \pi$ coupling constants, and the nonfactorizable amplitude of the decay $ B \ra J/\psi K$ in the framework of QCD sum rules.