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QCD predictions for spin dependent photonic structure function $g_1^γ(x,Q^2)$ in the low x region of future linear colliders

J. Kwiecinski·B. Ziaja
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Abstract

Spin dependent structure function $g_1^γ(x,Q^2)$ of the polarised photon is analysed within the formalism based upon the unintegrated spin dependent parton 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 $g_1^γ(x,Q^2)$ 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 $Δg^γ (x,Q^2)$ are also given.

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J. Kwiecinski, B. Ziaja. 2000-11-21. QCD predictions for spin dependent photonic structure function $g_1^γ(x,Q^2)$ in the low x region of future linear colliders. https://doi.org/10.1103/physrevd.63.054022

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