Pion to photon transition form factors with basis light-front quantization
| Autor: | Mondal, Chandan, Nair, Sreeraj, Jia, Shaoyang, Zhao, Xingbo, Vary, James P. |
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| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Phys. Rev. D 104, 094034 (2021) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1103/PhysRevD.104.094034 |
| Popis: | We obtain the distribution amplitude (DA) of the pion from its light-front wave functions in the basis light-front quantization framework. This light-front wave function of the pion is given by the lowest eigenvector of a light-front effective Hamiltonian consisting a three-dimensional confinement potential and the color-singlet Nambu--Jona-Lasinion interaction both between the constituent quark and antiquark. The quantum chromodynamics (QCD) evolution of the DA is subsequently given by the perturbative Efremov-Radyushkin-Brodsky-Lepage evolution equation. Based on this DA, we then evaluate the singly and doubly virtual transition form factors in the space-like region for $\pi^0\rightarrow \gamma^*\gamma$ and $\pi^0\rightarrow \gamma^*\gamma^*$ processes using the hard-scattering formalism. Our prediction for the pion-photon transition form factor agrees well with data reported by the Belle Collaboration. However, in the large $Q^2$ region it deviates from the rapid growth reported by the BaBar Collaboration. Meanwhile, our result on the $\pi^0\rightarrow \gamma^*\gamma^*$ transition form factor is also consistent with other theoretical approaches and agrees with the scaling behavior predicted by perturbative QCD. Comment: 15 pages, 5 figures, 3 tables; figure 3 and corresponding discussions added; version accepted by PRD |
| Databáze: | arXiv |
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