The single spin asymmetry $A_N$, for large $P_T$ single inclusive particle production in $p^{\uparrow }p$ collisions, is considered within a generalized parton model and a transverse momentum dependent factorization scheme. The focus is on the Sivers effect and the study of its potential contribution to $A_N$, based on a careful analysis of the Sivers functions extracted from azimuthal asymmetries in semi-inclusive deep inelastic scattering processes. It is found that such Sivers functions could explain most features of the $A_N$ data, including some recent STAR results which show the persistence of a nonzero $A_N$ up to surprisingly large $P_T$ values.

• Received 6 May 2013

DOI:https://doi.org/10.1103/PhysRevD.88.054023