PHENOMENOLOGICAL DETERMINATION OF POLARIZED QUARK DISTRIBUTIONS IN THE NUCLEON

We present a fit to spin asymmetries which gives polarized quark distr ibutions. These functions are closely related to the ones given by the Martin, Roberts and Stirling fit for unpolarized structure functions. The integrals of polarized distributions are discussed and compared w ith the corresponding quantities obtained from neutron and hyperon bet a-decay data. We use the combination of proton, neutron and deuteron s pin asymmetries in order to determine the coefficients of our polarize d quark distributions. Our fit shows that phenomenologically there is no need for taking polarized gluons into account.