Probing Quark Fragmentation Functions for Spin-1/2 Baryon Production in Unpolarized $e^{+}{e}^{-}$ Annihilation

Abstract

We study the measurement of the quark fragmentation functions for spin-1/2 baryon production ($\Lambda$ and $\bar{\Lambda }$, in particular) in unpolarized $e^{+}{e}^{-}$ annihilation. The spin-dependent fragmentation functions ${\hat{g}}_1(z)$ and ${\hat{h}}_1(z)$ can be probed in the process as a result of quark-antiquark spin correlation and the weak decay of the baryons. The relevant cross section is expressed as a product of the two-jet cross-section, the fragmentation functions, and the differential width of the hyperon decay.

Comments: 17 pages, ReVTeX with (1 figure available from authors), MIT-CTP: #2365