Nuclear Dependence of the Transverse-Single-Spin Asymmetry for Forward Neutron Production in Polarized p+A Collisions at √sNN=200 GeV

Scientific paper - Original scientific paper

• Author: C. Aidala
• Author: ...
• Author: Mirta Dumancic
• Author: ...
• Author: Mihael Makek; MBZ: 256122
• Author: ...
• Author: Nikola Vukman; MBZ: 362186
• Author: ...
• Author: L. Zou
• Collaboration: PHENIX Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

During 2015, the Relativistic Heavy Ion Collider (RHIC) provided collisions of transversely polarized protons with Au and Al nuclei for the first time, enabling the exploration of transverse-single-spin asymmetries with heavy nuclei. Large single-spin asymmetries in very forward neutron production have been previously observed in transversely polarized p+p collisions at RHIC, and the existing theoretical framework that was successful in describing the single-spin asymmetry in p+p collisions predicts only a moderate atomic-mass-number (A) dependence. In contrast, the asymmetries observed at RHIC in p+Acollisions showed a surprisingly strong A dependence in inclusive forward neutron production. The observed asymmetry in p+Al collisions is much smaller, while the asymmetry in p+Au collisions is a factor of 3 larger in absolute value and of opposite sign. The interplay of different neutron production mechanisms is discussed as a possible explanation of the observed A dependence.

• Keywords (english): Transverse Spin Asymmetry; Neutron; p+A; 200 GeV; PHENIX; RHIC
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical Review Letters
• Numbering: vol. 120, no. 2, 022001
• p-ISSN: 0031-9007
• DOI: https://doi.org/10.1103/physrevlett.120.022001
• URN:NBN: urn:nbn:hr:217:259150
• Publication: 2018
• Document URL: https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.022001
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2018 American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/). Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3. Received 3 April 2017; revised manuscript received 26 September 2017; published 8 January 2018.
• Created on: 2020-02-29 21:04:59