Rapidity Dependence of Antiproton-to-Proton Ratios in Au+Au Collisions at

Journal Article · Mon Sep 10 04:00:00 EDT 2001 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.87.112305· OSTI ID:40277572

Bearden, I G; Beavis, D; Besliu, C; Blyakhman, Y; Brzychczyk, J; Budick, B; Boggild, H; Chasman, C; Christensen, C H; Christiansen, P ^[1]

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1. and others

Measurements, with the BRAHMS detector, of the antiproton-to-proton ratio at midrapidities and forward rapidities, are presented for Au+Au reactions at s{sub NN}=130 GeV , and for three different collision centralities. For collisions in the 0%--40% centrality range, we find N({bar p})/N(p)=0.64{+-} 0.04{sub (stat)}{+-}0.06{sub ( syst)} at y{approx}0 , 0.66{+-}0.03{+-}0.06 at y{approx}0.7 , and 0.41{+-}0.04{+-}0.06 at y{approx}2 . The ratios are found to be nearly independent of collision centrality and transverse momentum. The antiproton and proton rapidity densities vary differently with rapidity, and indicate a significant degree of collision transparency, although a net-baryon free midrapidity plateau (Bjorken limit) is not yet reached.

• Research Organization: Brookhaven National Laboratory
• Sponsoring Organization: (US)
• DOE Contract Number: AC02-98CH10886; FG02-99ER41121; FG03-93ER40773; FG03-96ER40981
• OSTI ID: 40277572
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 11 Vol. 87; ISSN 0031-9007
• Publisher: The American Physical Society
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTIPROTONS
PROTONS
TRANSVERSE MOMENTUM