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arXiv · hep-lat/0209100

The radial distributions of a heavy-light meson on a lattice

J. Koponen·A. M. Green·C. Michael·P. Pennanen
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Abstract

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 quark-gluon coupling of 5.7, a lattice spacing of 0.17 fm, and a hopping parameter corresponding to a light quark mass about that of the strange quark. Several improvements are now made: 1) The configurations are generated using dynamical fermions with a quark-gluon coupling of 5.2 (a lattice spacing of 0.14 fm); 2) Many more gauge configurations are included (78 compared with the earlier 20); 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 charge and matter distributions can be described by mesons of mass 0.9+-0.1 and 1.5+-0.1 GeV respectively - values that are consistent with those of vector and scalar qqbar-states calculated directly with the same lattice parameters.

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J. Koponen, A. M. Green, C. Michael, P. Pennanen. 2002-09-10. The radial distributions of a heavy-light meson on a lattice. https://doi.org/10.1016/s0920-5632(03)01610-4

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