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arXiv · 1810.08497

Sub-leading power corrections to transition form factors of $η$ and $η^{\prime}$ mesons from twist-six contributions

Janardan P. Singh·Shesha D. Patel
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Abstract

Using collinear factorization, we have calculated twist-six corrections to $ηγ$ and $η^{\prime}γ$ transition form factors in QCD. Only a sub-set of light-cone operators of twist-six which can be factorized as a product of two gauge invariant operators has been considered. Resulting power corrections start as $1/Q^{4}$ but coefficients are smaller compared to their counterparts for twist-four operators. Matrix element of pseudoscalar quark densities for $u$- and $d$-quarks between vacuum and meson state, $h_{q}$, has considerable influence on the result. Results obtained by superimposing our results on those obtained in literature for leading and sub-leading power corrections for lower twists have been plotted and compared with data.

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Janardan P. Singh, Shesha D. Patel. 2018-10-19. Sub-leading power corrections to transition form factors of $η$ and $η^{\prime}$ mesons from twist-six contributions. https://doi.org/10.1088/1361-6471%2Faaeb9f

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