Observation of Two-Source Interference in the Photoproduction Reaction AuAu → AuAu ρ0

Scientific paper - Original scientific paper

• Author: B. I. Abelev
• Author: ...
• Author: Mirko Planinić
• Author: ...
• Author: Nikola Poljak
• Author: ...
• Author: J. X. Zuo
• Collaboration: STAR Collaboration
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

In ultraperipheral relativistic heavy-ion collisions, a photon from the electromagnetic field of one nucleus can fluctuate to a quark-antiquark pair and scatter from the other nucleus, emerging as a ρ0. The ρ0 production occurs in two well-separated (median impact parameters of 20 and 40 F for the cases considered here) nuclei, so the system forms a two-source interferometer. At low transverse momenta, the two amplitudes interfere destructively, suppressing ρ0 production. Since the ρ0 decays before the production amplitudes from the two sources can overlap, the two-pion system can only be described with an entangled nonlocal wave function, and is thus an example of the Einstein-Podolsky-Rosen paradox. We observe this suppression in 200 GeV per nucleon-pair gold-gold collisions. The interference is 87%±5%(stat.)±8%(syst.) of the expected level. This translates into a limit on decoherence due to wave function collapse or other factors of 23% at the 90% confidence level.

• Keywords (english): ultra-peripheral relativistic heavy-ion collisions
• 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. 102, no. 11, 112301
• p-ISSN: 0031-9007
• e-ISSN: 1079-7114
• DOI: https://doi.org/10.1103/PhysRevLett.102.112301
• URN:NBN: urn:nbn:hr:217:412883
• Publication: 2009
• Project: Number: 119-0982887-1006; Title (croatian): Istraživanje hadronskih sustava upotrebom relativističkih projektila; Leader: Mirko Planinić; Jurisdiction: Croatia; Funding stream: ZP
• Document URL: http://link.aps.org/doi/10.1103/PhysRevLett.102.112301
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2009) by the American Physical Society. Received 4 December 2008; published 16 March 2009.
• Created on: 2019-10-19 19:51:37