Abstract
The PHENIX experiment at the BNL Relativistic Heavy Ion Collider recently reported transverse single-spin asymmetry, , for forward neutrons in collisions at . in and collisions were measured as and 0.18, respectively. These values are clearly different from the measured in collisions. In this paper, I propose that a large for forward neutrons in ultraperipheral collisions may explain the PHENIX measurements. The proposed model is demonstrated using two Monte Carlo simulations. In the ultraperipheral collision simulation, I use the starlight event generator for the simulation of the virtual photon flux and then use the maid2007 unitary isobar model for the simulation of neutron production in the interactions of a virtual photon with a polarized proton. In the hadronic interaction simulation, the differential cross sections for forward neutron production are predicted by a simple one-pion exchange model and the Glauber model. The simulated values for both the contribution of ultraperipheral collisions and the hadronic interactions are in good agreement with the PHENIX results.
- Received 17 February 2017
DOI:https://doi.org/10.1103/PhysRevC.95.044908
©2017 American Physical Society