Lu, W (reprint author), ACAD SINICA,INST HIGH ENERGY PHYS,POB 9184,BEIJING 100039,PEOPLES R CHINA.
In contrast to the hadronic tenser. in the deeply inelastic scattering, we find that owing to the final-state interactions, time reversal invariance cannot make any constraint to the general expression of the photon fragmentation tensor for inclusive spin-half baryon production. Correspondingly, there exists a novel fragmentation structure function (F) over cap(z, Q(2)) that has no correspondence to any hadronic structure functions in the hadronic tensor of the deeply inelastic electron scattering off the spin-half baryon. Phenomenologically, (F) over cap(z, Q(2)) determines the transverse polarization of the inclusively detected baryon in unpolarized electron-positron annihilation. In relation to the large transverse Lambda polarization puzzle in fixed-target experiments, we suggest measuring the Lambda polarization in e(-) + e(+) -, Lambda + X.