Gauge Invariance and k_T-Factorization of Exclusive Processes
| dc.creator | Feng, F. | |
| dc.creator | Ma, J. P. | |
| dc.creator | Wang, Q. | |
| dc.date | 2008-07-02 | |
| dc.date | 2009-02-03 | |
| dc.date.accessioned | 2026-07-07T12:59:58Z | |
| dc.date.available | 2026-07-07T12:59:58Z | |
| dc.description | In the $k_T$-factorization for exclusive processes, the nontrivial $k_T$-dependence of perturbative coefficients, or hard parts, is obtained by taking off-shell partons. This brings up the question of whether the $k_T$-factorization is gauge invariant. We study the $k_T$-factorization for the case $πγ^* \to γ$ at one-loop in a general covariant gauge. Our results show that the hard part contains a light-cone singularity that is absent in the Feynman gauge, which indicates that the $k_T$-factorization is {\it not} gauge invariant. These divergent contributions come from the $k_T$-dependent wave function of $π$ and are not related to a special process. Because of this fact the $k_T$-factorization for any process is not gauge invariant and is violated. Our study also indicates that the $k_T$-factorization used widely for exclusive B-decays is not gauge invariant and is violated. | |
| dc.description | Add some explanation, conclusion unchanged. Version to appear in PLB | |
| dc.identifier | https://arxiv.org/abs/0807.0296 | |
| dc.identifier | http://arxiv.org/abs/0807.0296 | |
| dc.identifier | Phys.Lett.B674:176-181,2009 | |
| dc.identifier | doi:10.1016/j.physletb.2009.02.060 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/225737 | |
| dc.subject | High Energy Physics - Phenomenology | |
| dc.title | Gauge Invariance and k_T-Factorization of Exclusive Processes | |
| dc.type | text |