Interactions between heavy-light mesons in lattice QCD

Abstract

A potential between heavy-light mesons is extracted from quark correlation functions in the framework of quenched lattice QCD with Kogut-Susskind fermions. We show that the resulting potential is attractive at short distances. An analysis of the influence of the light quark mass on the interaction is performed.

Adjoint “quarks” on coarse anisotropic lattices: Implications for string breaking in full QCD

“…From one point of view, one would say that correlation functions give spectral information only: the ground state energy versus quark separation. In this view such information is useful, for example, in characterizing the effects of quenching on meson-meson interaction energies [41,42], but not in relation to processes such as hadronization, which can only occur in the presence of dynamical fermions. Then one might say that the difficulty in seeing "string breaking" with the Wilson loop at very large separations indicates nothing more than that this operator has a poor overlap with the ground state in this regime.…”

Partially quenched nucleon-nucleon scattering

“…Thus, measuring the long-distance behavior of the NN potential [25,26,27,28] does not provide information about QCD unless the hairpin contribution can be removed in a rigorous way. While the presence of this behavior is quite discouraging, one might focus on the behavior of S-matrix elements rather than on the NN potential itself (for a recent survey of the status of lattice calculations of the NN potential see Ref.…”

Exploring the π + -π + Interaction in Lattice QCD

“…In simulations of heavy-light meson-meson systems performed in coordinate space [19] the above mechanism is seen directly. There, the r = 0 case can be easily isolated.…”

“…Naturally, C (4) may be expressed in terms of the 2-point correlator C (2) . Using (4) and (19), (20) gives…”

“…Extending this line of work, studies of heavy-light meson-meson systems were done [19] where the heavy quarks are treated as static and the light valence quarks are dynamic in the sense that their propagation is computed from the fermionic, staggered, lattice action. Although these studies are numerically difficult it appears that an attractive force between the partners is a common feature.…”