2008/12/31 by B. I. Abelev, M. M. Aggarwal, Z. Ahammed +96 · 1 citation
Physics and Astronomy · #Atomic and Molecular Physics #Cold Atom Physics and Bose-Einstein Condensates #Quantum Chromodynamics and Particle Interactions #hep-ex #nucl-ex #quant-ph
paper · pdf · doi:10.1103/physrevlett.102.112301
published as Phys.Rev.Lett.102:112301,2009 · Slightly revised version, to appear in PRL. 6 pages with 4 figures
arxiv created 2009/03/02 · openalex publication_date 2009/03/16 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01
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 rho0. The rho0 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 rho0 production. Since the rho0 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.