Order $\alpha_s(Q^2)$ QCD corrections to the polarised $e^+~e^- \to \Lambda ~X$

Abstract

The importance of polarised gluons fragmenting into $\Lambda$ in the polarised $e^+ e^-$ annihilation is discussed using the Altarelli-Parisi evolution equations satisfied by the quark and gluon fragmentation functions. In this context, the polarised fragmentaion function $\hat g_1^\Lambda(x,Q^2)$ appearing in the cross section is discussed within the parton model. We relate this fragmentation function to the quark, anti-quark and gluon fragmentation functions and also find the QCD corrections to order $\alpha_s$.