Related papers: Hybrid potentials versus gluelumps
The heavy quark-antiquark potential in perturbative QCD is subject to ambiguities. We show how to derive a well-defined and stable short-distance potential that can be matched to results from lattice QCD simulations at intermediate…
In the framework of quark models, hybrid mesons are either seen as two-body $q\bar q$ systems with an excited flux tube connecting the quark to the antiquark or as three-body $q\bar q g$ systems including a constituent gluon. In this work…
Using a generalized polar decomposition of the gauge fields into gauge-rotation and gauge-invariant parts, which Abelianises the Non-Abelian Gauss-law constraints, an unconstrained Hamiltonian formulation of QCD can be achieved. The exact…
We consider quarkonium in a hot QCD plasma which, due to expansion and non-zero viscosity, exhibits a local anisotropy in momentum space. At short distances the heavy-quark potential is known at tree level from the hard-thermal loop…
The decay of 2-gluon colour singlets in quarks: 2g --> q-qbar +2q-2qbar has been simulated with the Monte-Carlo method, taking into account an effective 1-gluon exchange interaction between the emitted quarks, which was folded with a…
We derive the Polyakov-loop thermodynamic potential in the perturbative approach to pure SU(3) Yang-Mills theory. The potential expressed in terms of the Polyakov loop in the fundamental representation corresponds to that of the…
We report on a recent QCD based research on hybrid mesons containing $c\bar c$ or $b\bar b$ quarks. We present results for the spectrum, the decay widths to heavy quarkonium, and the role of mixing with the latter. We point out that mixing…
We use on-shell recursion relations to determine the one-loop QCD scattering amplitudes with a massless external quark pair and an arbitrary number (n-2) of positive-helicity gluons. These amplitudes are the last of the unknown infrared-…
We extend our treatment of the the spectroscopy and decays of the charm-strange quarkonium system to include the effect of using the full three-loop QCD correction to the static short distance potential. As before, our potential model…
The layered graphene systems exhibit the rich and unique excitation spectra arising from the electron-electron Coulomb interactions. The generalized tight-binding model is developed to cover the planar/buckled/cylindrical structures,…
We examine the couplings of quarkonium hybrids to heavy-light meson pairs in the Born-Oppenheimer approximation for QCD. The lowest hybrid multiplets consist of bound states of the $\Pi_u$ and $\Sigma_u^-$ potentials. We find that the…
Model-independent features of hybrid states with heavy quarks and adiabatic approximation for such systems are discussed.These general arguments are applied to the QCD-based constituent gluon model.The leading- order Hamiltonian is derived…
The $Q \bar{Q}$ semirelativistic interaction in QCD can be expressed in terms of the Wilson loop and its functional derivatives. In this framework we discuss the complete (velocity and spin dependent) $1/m^2$ potential in the stochastic…
For a complete description of the physical properties of low-energy QCD, it might be advantageous to first reformulate QCD in terms of gauge-invariant dynamical variables, before applying any approximation schemes. Using a canonical…
A constituent gluon model that is informed by recent lattice field theory is developed. The model is then used to compute hybrid strong decay widths, that can be useful for the GlueX collaboration at Jefferson Lab and the PANDA…
We discuss the spectrum of hadrons with a heavy colour-adjoint particle - motivated by the gluino of supersymmetry. Using the lattice approach, we explore in detail the gluonic bound states - the `glueballino' or `gluelump'. We also make a…
We compute the energy of the ground state and a low lying excitation of the gluonic field in the presence of static quark -anti-quark ($\qq$) sources. We show that for separation between the sources less then a few fm the gluonic ground…
The effective QCD Hamiltonian is constructed with the help of the background perturbation theory, and relativistic Feynman--Schwinger path integrals for Green's functions. The resulting spectrum displays mass gaps of the order of one GeV,…
We discuss the non-perturbative computation and interpretation of a colour adjoint static potential based on Wilson loops with generator insertions. Numerical lattice results for SU(2) gauge theory are presented and compared to…
The notion of constituent gluon is introduced as a gluon propagating in the vacuum background field. The Hamiltonian approach for a system containing such gluon and a $q\bar{q}g$ pair is formulated, and the masses of lowest $q\bar{q}g$…