Doubly heavy baryons in a Salpeter model with AdS/QCD inspired potential

The mass spectra and wave functions for the doubly heavy baryons with $J^P=1^+$ heavy diquark core

The mass spectra and wave functions for the doubly heavy baryons are computed under the picture that the two heavy quarks inside a doubly heavy baryon, such as two $c$-quarks in $Ξ_{cc}$, combine into a heavy `diquark core' in color anti-triplet firstly, then the diquark core turns into a color-less doubly heavy baryon via combining the light $q$-quark inside the baryon. Namely both of the combinations, the two heavy quarks inside the baryon into a diquark core in color anti-triplet and the heavy diquark core with the light quark into the baryon, are depicted by relativistic Bethe-Salpeter equ…

双重和三重重子的磁矩和辐射衰变宽度的动力学重双夸克模型

Magnetic moments and radiative decay widths of doubly- and triply-heavy baryons in the dynamical heavy diquark model

本文基于动力学重双夸克模型计算双重和三重重子的磁矩和辐射衰变宽度，结合Bethe-Salpeter方程推导重双夸克质量方程，并与现有数据和预测进行比较。

Doubly charmed $Ξ_{cc}$ molecular states from meson-baryon interaction

Stimulated by the new experimental LHCb findings associated with the $Ω_c$ states, some of which we have described in a previous work as being dynamically generated through meson-baryon interaction, we have extended this approach to make predictions for new $Ξ_{cc}$ molecular states in the $C=2$, $S=0$ and $I=1/2$ sector. These states manifest themselves as poles in the solution of the Bethe-Salpeter equation in coupled channels. The kernels of this equation were obtained using the Lagrangians coming from the hidden local gauge symmetry, where the interactions are dominated by the exchange of …

AdS-QCD quark-antiquark potential, meson spectrum and tetraquarks

AdS/QCD correspondence predicts the structure of quark-antiquark potential in the static limit. We use this piece of information together with the Salpeter equation (Schrödinger equation with relativistic kinematics) and a short range hyperfine splitting potential to determine quark masses and the quark potential parameters from the meson spectrum. The agreement between theory and experimental data is satisfactory provided one considers only mesons comprising at least one heavy quark. We use the same potential (in the one-gluon-exchange approximation) and these data to estimate constituent diq…

Hidden and doubly heavy molecular states from interactions $D^{(*)}_{(s)}{\bar{D}}^{(*)}_{s}$/$B^{(*)}_{(s)}{\bar{B}}^{(*)}_{s}$ and ${D}^{(*)}_{(s)}D_{s}^{(*)}$/${B}^{(*)}_{(s)}B_{s}^{(*)}$

In this work, we perform a systematical investigation about the possible hidden and doubly heavy molecular states with open and hidden strangeness from interactions of $D^{(*)}{\bar{D}}^{(*)}_{s}$/$B^{(*)}{\bar{B}}^{(*)}_{s}$, ${D}^{(*)}_{s}{\bar{D}}^{(*)}_{s}$/${B}^{(*)}_{s}{\bar{B}}^{(*)}_{s}$, ${D}^{(*)}D_{s}^{(*)}$/${B}^{(*)}B_{s}^{(*)}$, and $D_{s}^{(*)}D_{s}^{(*)}$/$B_{s}^{(*)}B_{s}^{(*)}$ in a quasipotential Bethe-Salpeter equation approach. The interactions of the systems considered are described within the one-boson-exchange model, which includes exchanges of light mesons and $J/ψ/Υ$ …

Virtual Compton Scattering off a Spinless Target in AdS/QCD

We study the doubly virtual Compton scattering off a spinless target $γ^*P\toγ^*P'$ within the Anti-de Sitter(AdS)/QCD formalism. We find that the general structure allowed by the Lorentz invariance and gauge invariance of the Compton amplitude is not easily reproduced with the standard recipes of the AdS/QCD correspondence. In the soft-photon regime, where the semi-classical approximation is supposed to apply best, we show that the measurements of the electric and magnetic polarizabilities of a target like the charged pion in real Compton scattering, can already serve as stringent tests.

Virtual Compton Scattering off a Spinless Target in the AdS/QCD correspondence

We perform a study of the doubly virtual Compton scattering off a spinless target gamma* P -> gamma* P' within the Anti-de Sitter(AdS)/QCD formalism. We find that the general structure allowed by the Lorentz invariance and gauge invariance of the Compton amplitude is not easily reproduced with the standard recipes of the AdS/QCD correspondence. In the soft-photon regime, where the semi-classical approximation is supposed to apply best, we show that the measurements of the electric and magnetic polarizabilities of a target like the charged pion in real Compton scattering, can already serve as s…

The doubly virtual $(π^0,η,η')\toγ^*γ^*$ transition form factors in the light-front quark model

We report our investigation on the doubly virtual TFFs $F_{{\rm P}γ^*}(Q^2_1,Q^2_2)$ for the ${\rm P}\toγ^*(q_1)γ^*(q_2) \;({\rm P}=π^0,η,η')$ transitions using the light-front quark model (LFQM). Performing a LF calculation in the exactly solvable manifestly covariant Bethe-Salpeter (BS) model as the first illustration, we used $q^+_1=0$ frame and found that both LF and manifestly covariant calculations produce exactly the same results for $F_{{\rm P}γ^*}(Q^2_1,Q^2_2)$. This confirms the absence of the LF zero mode in the doubly virtual TFFs. We then mapped this covariant BS model to the stan…

Molecular states from $D^{(*)}\bar{D}^{(*)}/B^{(*)}\bar{B}^{(*)}$ and $D^{(*)}D^{(*)}/\bar{B}^{(*)}\bar{B}^{(*)}$ interactions

In this work, we preform a systematic investigation about hidden heavy and doubly heavy molecular states from the $D^{(*)}\bar{D}^{(*)}/B^{(*)}\bar{B}^{(*)}$ and $D^{(*)}D^{(*)}/\bar{B}^{(*)}\bar{B}^{(*)}$ interactions in the quasipotential Bethe-Salpeter equation (qBSE) approach. With the help of Lagrangians with heavy quark and chiral symmetries, interaction potentials are constructed within the one-boson-exchange model in which we include the $π$, $η$, $ρ$, $ω$ and $σ$ exchanges, as well as $J/ψ$ or $Υ$ exchange. Possible bound states from the interactions considered are searched for as the…

Condensates in Quantum Chromodynamics and the Cosmological Constant

Casher and Susskind have noted that in the light-front description, spontaneous chiral symmetry breaking in quantum chromodynamics (QCD) is a property of hadronic wavefunctions and not of the vacuum. Here we show from several physical perspectives that, because of color confinement, quark and gluon QCD condensates are associated with the internal dynamics of hadrons. We discuss condensates using condensed matter analogues, the AdS/CFT correspondence, and the Bethe-Salpeter/Dyson-Schwinger approach for bound states. Our analysis is in agreement with the Casher and Susskind model and the explici…