A determination of gluon spin distribution from the deep inelastic scattering data
In order to determine polarized parton densities in nucleon we have made fits using all experimental data on spin asymmetries measured in the deep inelastic scattering on different nucleon targets. We have used in our analysis next to leading order QCD corrections in bar{MS} renormalization scheme. The functional forms of polarized densities are based on the fit to unpolarized deep inelastic data made by the MRST group (MRST 99). We have concentrated on different models for gluon spin distributions. In the best fit we get for gluon polarization (at Gev^{2}) Delta G=-1.0 +/- 0.6. The obtained result does not depend very much on various model assumptions
Spin Muon Collaboration (SMC)
We present a measurement of the longitudinal spin cross section asymmetry for deep inelasticmuon-nucleon interactions with two high transverse momentum hadrons in the ﬁnal state. Twomethods of event classiﬁcation are used to increase the contribution of the Photon Gluon Fusionprocess to above 30%. The most eﬀective one, based on a neural network approach, provides theasymmetries A
Direct evidence for the single cell origin of mouse liver cell tumours.
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