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arXiv · 1604.04441

The leading twist light-cone distribution amplitudes for the S-wave and P-wave Bc mesons

Ji Xu·Deshan Yang
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Abstract

The light-cone distribution amplitudes (LCDAs) serve as important non-perturbative inputs for the study of hard exclusive processes. In this paper, we calculate ten LCDAs at twist-2 for the S-wave and P-wave $B_c$ mesons up to the next-to-leading order (NLO) of the strong coupling $α_s$ and leading order of the velocity expansion. Each one of these ten LCDAs is expressed as a product of a perturbatively calculable distribution and a universal NRQCD matrix-element. By use of the spin symmetry, only two NRQCD matrix-elements will be involved. The reduction of the number of non-perturbative inputs will improve the predictive power of collinear factorization.

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Ji Xu, Deshan Yang. 2016-07-21. The leading twist light-cone distribution amplitudes for the S-wave and P-wave Bc mesons. https://doi.org/10.1007/jhep07(2016)098

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