H. Ito

Quark Gluon Plasma and Color Glass Condensate at RHIC? The perspective from the BRAHMS experiment.

We review the main results obtained by the BRAHMS collaboration on the properties of hot and dense hadronic and partonic matter produced in ultrarelativistic heavy ion collisions at RHIC. A particular focus of this paper is to discuss to what extent the results collected so far by BRAHMS, and by the other three experiments at RHIC, can be taken as evidence for the formation of a state of deconfined partonic matter, the so called quark-gluon-plasma (QGP). We also discuss evidence for a possible precursor state to the QGP, i.e. the proposed Color Glass Condensate.

Transverse momentum spectra in Au+Au and d+Au collisions at s**(1/2) = 200-GeV and the pseudorapidity dependence of high p(T) suppression

We present spectra of charged hadrons from Au+Au and d+Au collisions at sqrt[s(NN)]=200 GeV measured with the BRAHMS experiment at RHIC. The spectra for different collision centralities are compared to spectra from p+(-)p collisions at the same energy scaled by the number of binary collisions. The resulting ratios (nuclear modification factors) for central Au+Au collisions at eta=0 and eta=2.2 evidence a strong suppression in the high p(T) region (>2 GeV/c). In contrast, the d+Au nuclear modification factor (at eta=0) exhibits an enhancement of the high p(T) yields. These measurements indicate a high energy loss of the high p(T) particles in the medium created in the central Au+Au collisions. The lack of suppression in d+Au collisions makes it unlikely that initial state effects can explain the suppression in the central Au+Au collisions.

Centrality dependent particle production at y=0 and y ~ 1 in Au + Au collisions at s(NN)**(1/2) = 200-GeV

Particle production of identified charged hadrons,

Production of Mesons and Baryons at High Rapidity and High p{sub T} in Proton-Proton Collisions at {radical}(s)=200 GeV

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Nuclear stopping and rapidity loss in Au+Au collisions at sNN=62.4 GeV

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Kaon and pion production in central Au + Au collisions at sNN=62.4 GeV

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Results from the BRAHMS experiment at RHIC

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Towards measuring pseudorapidity dependence in elliptic flow at BRAHMS

p

Forward and midrapidity like-particle ratios from p+p collisions at √s=200 GeV

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Rapidity Dependence of Charged Antiparticle-to-Particle Ratios in Au+Au Collisions at

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