相关论文: String Breaking in Two-Dimensional QCD

The variational einbein field method is applied to the model of the QCD string with quarks at the ends for the case of light-light and heavy-light mesons. Special attention is payed to the proper string dynamics. The correct string slope of…

We propose the stringy description of the system consisting of two heavy and four light quarks in the case of two light flavors of equal mass. As an application, we consider the three low-lying Born-Oppenheimer potentials as a function of…

When a heavy quark and the corresponding antiquark are separated by more than $1.4 - 1.5$ fm, it becomes energetically favorable for a light quark-antiquark pair to be produced, leading to fragmentation into a pair of flavored mesons. The…

We continue our investigation of the effective string model for the triply heavy quark system, mimicking that in pure $SU(3)$ gauge theory. We present analytical and numerical studies of the three-quark potential for isosceles and collinear…

We study the effects of dynamical quarks on the static quark potential at distances shorter than those where string breaking is expected. Quenched calculations and calculations with three flavors of dynamical quarks are done on sets of…

QCD exhibits complex dynamics near S-wave two-body thresholds. For light mesons, we see this in the failure of quark models to explain the $f_0(500)$ and $K_0^*(700)$ masses. For charmonium, an unexpected $X(3872)$ state appears at the open…

We propose a holographic description of heavy-light mesons, i.e. of mesons containing a light and a heavy quark. In the semi-classical string limit, we look at the dynamics of strings tied between two D7 branes. We consider this setup both…

We study the heavy-heavy-light quark ($QQq$) potential in SU(3) quenched lattice QCD, and discuss one of the roles of the finite-mass valence quark in the inter-quark potential. Monte Carlo simulations are performed with the standard gauge…

We revisit the recipe for hadron formation in the Lund string hadronization model. Given an incoming quark or quark-diquark pair, weights for hadron formation are updated to take hyperfine splitting effects arising from the mass difference…

We review and elaborate on properties of the string tension in two-dimensional gauge theories. The first model we consider is massive QED in the $m\ll e$ limit. We evaluate the leading string tension both in the fermionic and bosonized…

I report on a lattice computation of the energy of a system of two light quarks and two static antiquarks as a function of the separation of the static antiquarks. In terms of hadrons such a system corresponds to a pair of B mesons and its…

The spectra of some 0++ four-quark states, which are composed of \bar qq pairs, are calculated in QCD. The light four-quark states are calculated using the traditional sum rules while four-quark states containing one heavy quark are…

The potential between two heavy-light mesons as a function of the heavy quark separation is calculated in quenched SU(3) lattice QCD. We study the case of heavy-light mesons with a static heavy quark and light quarks of mass close to the…

We study the real-time dynamics of string breaking in quantum electrodynamics in one spatial dimension. A two-stage process with a clear separation of time and energy scales for the fermion--antifermion pair creation and subsequent charge…

In order to understand the binding of four static quarks, flux distributions corresponding to these binding energies are studied in quenched SU(2) and also related to a model for the energies. The potential relevant to string breaking…

The static gluon-quark-antiquark interaction is investigated using lattice QCD techniques. A Wilson loop adequate to the static hybrid three-body system is developed and, using a $24^3 \times 48$ periodic lattice with $\beta = 6.2$, the…

Bound states of heavy $\bar{q}q$ quarks are reviewed within the context of QCD, paying attention to what can be derived from the theory with a reasonable degree of rigour. This is compared with the results of semiclassical arguments. Among…

We consider the phenomenon of string breaking in the context of the spatial Wilson loops using the gauge/string duality. In particular, we discuss the impact of light flavors on the pseudopotential. We also introduce the notion of the…

We present a model for string breaking based on the existence of chromoelectric flux tubes. We predict the form of the long-range potential, and obtain an estimate of the string breaking length. A prediction is also obtained for the…

We report on our ongoing lattice QCD computation of antistatic-antistatic potentials in the presence of two light quarks using the CLS $N_f=2$ gauge configurations and the OpenQ*D codebase. We utilize a set of 16 creation operators,…