Perturbative Pion Form Factor Reexamined
نویسندگان
چکیده
We recalculate the pion electromagnetic form factor based on the pertur-bative QCD formalism that includes the Sudakov resummation. We take into account the evolution of the pion wave function in b, which represents the transverse extent of the pion. An infrared enhancement is observed when 1/b approaches Λ QCD. We propose to freeze the evolution of the wave function at some scale above Λ QCD , such that perturbative contributions are stablized. Our predictions are consistent with experimental data, and insensitive to the variation of relevant parameters.
منابع مشابه
Reexamination of the perturbative pion form factor with Sudakov suppression.
The perturbative pion form factor with Sudakov suppression is reexamined. Taking into account the multi-gluon exchange in the law Q 2 regions, we suggest that the running coupling constant should be frozen at α s (t = < k 2 T >) and < k 2 T > is the average transverse momentum which can be determined by the pionic wave function. In addition, we correct the previous calculations about the Sudako...
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