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arXiv · hep-ph/0402100

Twist-3 Distribute Amplitude of the Pion in QCD Sum Rules

Tao Huang·Xing-Hua Wu·Ming-Zhen Zhou
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Abstract

We apply the background field method to calculate the moments of the pion two-particles twist-3 distribution amplitude (DA) $ϕ_p(ξ)$ in QCD sum rules. In this paper,we do not use the equation of motion for the quarks inside the pion since they are not on shell and introduce a new parameter $m_0^p$ to be determined. We get the parameter $m_0^p\approx1.30GeV$ in this approach. If assuming the expansion of $ϕ_p(ξ)$ in the series in Gegenbauer polynomials $C_n^{1/2}(ξ)$, one can obtain its approximate expression which can be determined by its first few moments.

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Tao Huang, Xing-Hua Wu, Ming-Zhen Zhou. 2004-04-13. Twist-3 Distribute Amplitude of the Pion in QCD Sum Rules. https://doi.org/10.1103/physrevd.70.014013

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