Manifestation of s → Λ fragmentation matrix elements via transverse Λ polarization in unpolarized e−e+ annihilation

Making use of the collinear expansion technique developed by Ellis, Furmanski and Petrozio, and the special propagator concept invented by Qiu, we present a factorization approach to the photon fragmentation tensor for the inclusive Lambda hyperon production. As a result, the structure function F, which is related to the transverse polarization of the inclusive Lambda hyperon in unpolarized electron-positron annihilation, is expressed as a combination of four parton fragmentation matrix elements. Since the inclusive Λ production we considered is theoretically the simplest, our study can be taken as a question to the operatability and practability of the first nonleading QCD factorization theorem in the transverse Λ polarization phenomena.