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arXiv · 1107.5085

Charmed Mesons Have No Discernable Color-Coulomb Attraction

T. Goldman·Richard R. Silbar
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Abstract

Starting with a confining linear Lorentz scalar potential V_s and a Lorentz vector potential V_v which is also linear but has in addition a color-Coulomb attraction piece, -alpha_s/r, we solve the Dirac equation for the ground-state c- and u-quark wave functions. Then, convolving V_v with the u-quark density, we find that the Coulomb attraction mostly disappears, making an essentially linear barV_v for the c-quark. A similar convolution using the c-quark density also leads to an essentially linear tildeV_v for the u-quark. For bound cbar-c charmonia, where one must solve using a reduced mass for the c-quarks, we also find an essentially linear widehatV_v. Thus, the relativistic quark model describes how the charmed-meson mass spectrum avoids the need for a color-Coulomb attraction.

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T. Goldman, Richard R. Silbar. 2011-07-25. Charmed Mesons Have No Discernable Color-Coulomb Attraction. https://doi.org/10.1103/physrevc.85.015203

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