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arXiv · 0808.1526

Comment on "Gauge Invariance and $k_T$-Factorization of Exclusive Processes"

Hsiang-nan Li·Satoshi Mishima
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Abstract

We point out mistakes made in the one-loop calculation of some diagrams for the process $πγ^* \to γ$ in the preprint arXiv:0807.0296, and present correct results. Especially, we have difficulty to understand their argument that a highly off-shell gluon generates a light-cone (infrared) singularity. It is shown by means of the Ward identity that the gauge-dependent light-cone singularity found in arXiv:0807.0296 does not exist. It is then shown that a hard kernel derived in the $k_T$ factorization of exclusive processes is gauge invariant and free of the light-cone singularity.

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Hsiang-nan Li, Satoshi Mishima. 2009-03-02. Comment on "Gauge Invariance and $k_T$-Factorization of Exclusive Processes". https://doi.org/10.1016/j.physletb.2009.03.015

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