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arXiv · hep-ph/9401225

The Instantaneous Approximation to the Transition Matrix Elements between Two Bound States

Chao-Hsi Chang·Yu-Qi Chen
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Abstract

Under the framework of the Bethe-Salpeter (B.S.) wave functions and the Mandelstam formalism as well, to make ``instantaneous approximation'' to a transition matrix element (a current operator sandwiched between two bound-states of double heavy quarks) is described. By taking the typical concerned decays as examples, such as $B_c$ meson decaying to $J/ψ+ (\bar l ν)$, the advantages of the approach and its limitations are illustrated. Finally, potential applications to various processes for possible double heavy flavoured systems, such as those of $(Q' \bar Q)$ and $(Q' Q)$ ($m_Q, m_{Q'}\gg Λ_{QCD}$), are discussed.

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Chao-Hsi Chang, Yu-Qi Chen. 1994-01-10. The Instantaneous Approximation to the Transition Matrix Elements between Two Bound States. https://arxiv.org/abs/hep-ph/9401225

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