Speaker
Description
We discuss production of Drell-Yan lepton pairs at hadron colliders
in the framework of the Parton Reggeization Approach, which includes
off-shell initial state effects in a gauge-invariant way. Other
possible prescriptions to restore gauge-invariance of
hard-scattering coefficient with off-shell initial-state partons are
also investigated and significant differences for the resulting
structure functions are found, especially for the
$F_{UU}^{(\cos2\phi)}$. We compare our numerical results for
$q_T$-spectra of the lepton pair with experimental data, obtained by
E-288 collaboration ($\sqrt{S}=19.4$ and 23.8 GeV) and find a good
agreement. Also we perform predictions for the Drell-Yan structure
functions at NICA $pp$-collider ($\sqrt{S}=24$ GeV).
