The charge and matter radial distributions of heavy-light mesons calculated on a lattice with dynamical fermions

Abstract.

A knowledge of the radial distributions of quarks inside hadrons could lead to a better understanding of the QCD description of these hadrons and possibly suggest forms for phenomenological models. As a step in this direction, in an earlier work, the charge (vector) and matter (scalar) radial distributions of heavy-light mesons were measured in the quenched approximation on a $16^3\times 24$ lattice with a lattice spacing of $a\approx 0.17$ fm, and a hopping parameter corresponding to a light quark mass about that of the strange quark. Here several improvements are now made: 1) The configurations are generated using dynamical fermions with $a\approx 0.14$ fm; 2) Many more gauge configurations are included; 3) The distributions at many off-axis, in addition to on-axis, points are measured; 4) The data analysis is much more complete. In particular, distributions involving excited states are extracted. The exponential decay of the cha rge and matter distributions can be described by mesons of mass 0.9$\pm 0.1$ and 1.5$\pm 0.1$ GeV respectively - values that are consistent with those of vector and scalar $q\bar{q}$-states calculated directly with the same lattice parameters.