QCD predictions for spin dependent photonic structure function g γ 1 ( x , Q 2 ) in the low x region of future linear colliders

QCD predictions for spin dependent photonic structure function g γ 1 (x, Q 2) in the low x region of future linear colliders Abstract Spin dependent structure function g γ 1 (x, Q 2) of the polarised photon is analysed within the formalism based upon the unintegrated spin dependent par-ton distributions incorporating the LO Altarelli-Parisi evolution and the double ln 2 (1/x) resummation at low values of Bjorken parameter x. We analyse the effects of the double ln 2 (1/x) resummation on the behaviour of g γ 1 (x, Q 2) in the low x region which may be accessible in future linear e + e − and eγ colliders. Sensitivity of the predictions on the possible nonperturbative gluon content of the polarised photons is analysed. Predictions for spin dependent gluon distribution ∆g γ (x, Q 2) are also given.