Analysis of the pion wave function in light - cone formalism ∗

Several general constraints are suggested to analyze the pionic valence-state wave function. It is found that the present model wave functions used in lightcone formalism of perturbative quantum chromodynamics have failed these requirements to fit the pionic formfactor data and the reasonable valence-state structure function which does not exceed the pionic structure function data for x → 1 simultaneously. Furthermore, it is pointed out that there is a possibility to find model wave functions which can satisfy all of general constraints. Also we show that there are two higher helicity (λ1 + λ2 = ±1) components in the light-cone wave function for the pion as a natural consequence from the Melosh rotation and it is speculated that these components should be incorporated into the perturbative quantum chromodynamics. Detailed Version. To be published in Phys.Rev.D Project supported by National Natural Science foundation of China and the grant LWTZ-1298 of Chinese Academy of Science. Mailing Address