English

Pion Decay Widths of D mesons

High Energy Physics - Phenomenology 2009-10-31 v2

Abstract

The pionic decay rates of the excited L=0,1L=0,1 DD mesons are calculated with a Hamiltonian model within the framework of the covariant Blankenbecler-Sugar {equation.} The interaction between the light quark and charm antiquark is described by a linear scalar confining and a screened one-gluon exchange interaction. The decay widths of the DD^* mesons obtain a contribution from the exchange current that is associated with the linear scalar confining interaction. If this contribution is taken into account along with the single quark approximation, the calculated decay rates of the charged DD^* mesons are readily below the current empirical upper limits if the axial coupling constant of the light constituent quarks is taken to be gAqg_A^q = 0.87, but reach the empirical upper limits if gAqg_A^q = 1. With the conventional values for gAqg_A^q, the calculated widths of the D1D_1 and D2D_2^* mesons fall somewhat below the experimental lower limits, leaving room for other decay modes as well, such as ππ\pi\pi decay. The unrealistically large contribution from the axial charge operator to the calculated pion decay width of the D1D_1 meson is suppressed by taking into account the exchange charge effects that are associated with the scalar linear confining and vector one-gluon exchange interactions. The predicted values for the pionic widths of the hitherto undiscovered L=1 D1D_1^* and D0D_0^* mesons are found to be smaller than previous estimates.

Keywords

Cite

@article{arxiv.hep-ph/0009095,
  title  = {Pion Decay Widths of D mesons},
  author = {K. O. E. Henriksson and T. A. Lahde and C. J. Nyfalt and D. O. Riska},
  journal= {arXiv preprint arXiv:hep-ph/0009095},
  year   = {2009}
}

Comments

24 pages, 3 figures, uses feynmf typos corrected, to be published in Nuclear Physics A, accepted version

R2 v1 2026-07-22T13:29:01.224Z