Leading neutrons from polarized pp collisions

Abstract

We calculate the cross section and single-spin azimuthal asymmetry, A_n(t) for inclusive neutron production in pp collisions at forward rapidities relative to the polarized proton. Absorptive corrections to the pion pole generate a relative phase between the spin-flip and non-flip amplitudes, which leads to an appreciable spin asymmetry. However, the asymmetry observed recently in the PHENIX experiment at RHIC at very small |t|~0.01GeV^2 cannot be explained by this mechanism.

Comments: 8 pages, 6 figures. Based on invited talks presented by B.K. at "Trueman Fest" at BNL, May 12, 2008, and at "Sixth International Conference on Perspectives in Hadronic Physics", ICTP, Trieste, May 12-16, 2008