Experimental Highlights of the RHIC Program

Experimental highlights of the RHIC program are reviewed

Reconstructing ρ0\rho^0 and ω\omega mesons from non-leptonic decays in C+C at 2AGeV

We predict transverse and longitudinal momentum spectra and yields of $\rho^0$ and $\omega$ mesons reconstructed from hadron correlations in C+C reactions at 2~AGeV. The rapidity and $p_T$ distributions for reconstructable $\rho^0$ mesons differs strongly from the primary distribution, while the $\omega$'s distributions are only weakly modified. We discuss the temporal and spatial distributions of the particles emitted in the hadron channel. Finally, we report on the mass shift of the $\rho^0$ due to its coupling to the $N^*(1520)$, which is observable in both the di-lepton and $\pi\pi$ channel. Our calculations can be tested with the Hades experiment at GSI, Darmstadt

Production at High pTp_T in Central Au+Au and p+pp+p collisions at sNN=200\sqrt{s_{_{NN}}} = 200 GeV in STAR

he $\rho^0$ production at high-$p_T$ (5.0 $\leq p_T \leq$ 10.0 GeV/$c$) measured in minimum bias $p+p$, Au+Au and central Au+Au collisions in the STAR detector are presented. The $\rho^0/\pi$ ratio measured in $p+p$ is compared to PYTHIA calculations as a test of perturbative quantum chromodynamics (pQCD) that describes reasonably well particle production from hard processes. The $\rho^0$ nuclear modification factor are also presented. In $p+p$ collisions, charged pions and (anti-)protons are measured in the range 5.0 $\leq p_T \leq$ 15.0 GeV/$c$ and the anti-particle to particle ratio and the baryon to meson ratios of these hadrons are discussed.Comment: 4 pages, 8 figures, proccedings for QM200

Identified Hadrons and Jet Chemistry for p+p and Au+Au Collisions at RHIC

The study of hadron spectra at high $p_{T}$ in p+p collisions provides a good test of perturbative quantum chromo-dynamic calculations (pQCD) and baseline for measurements of nuclear modification factors in Au+Au collisions. Using events triggered by the Barrel Electro-Magnetic Calorimeter, identified charged hadron transverse momentum ($p_T$) spectra are measured up to 15 GeV/$c$ at mid-rapidity ($\mid y\mid$ $<$ 0.5) and neutral kaon $p_T$ spectra up to 12 GeV/$c$ in p + p collisions at $\sqrt{s_{NN}}$ = 200 GeV. The particle ratios of $p/\pi^{+}$, $\bar{p}/\pi^{-}$ and $K^{\pm,0}$ / $\pi^{\pm}$ in p + p collisions are shown and compared with next-to-leading order pQCD calculations. In central Au+Au collisions, we report nuclear modification factors ($R_{AA}$) for pion, kaon, proton and $\rho$ and discuss several model calculations: color-charge dependence of jet quenching and jet conversion. Finally, centrality dependence of $R_{AA}$ at high $p_T$ ($>$ 5.5 GeV/c) for kaon are compared with that of pion in Au + Au collisions at 200 GeV.Comment: 6 pages, 4 figures, SQM 2009 contributio

Indication for π+π−\pi^+ \pi^- scattering in p+pp+p collisions at sNN=\sqrt{s_{_{NN}}} = 200 GeV

A $\rho(770)^0$ mass shift of about -40 MeV/$c^2$ was measured in $p+p$ collisions at $\sqrt{s_{_{NN}}} =$ 200 GeV at RHIC. Previous mass shifts have been observed at CERN-LEBC-EHS and CERN-LEP. We will show that phase space does not account for the $\rho(770)^0$ mass shift measured at RHIC, CERN-LEBC-EHS and CERN-LEP and conclude that there are significant scattering interactions in $p+p$ collisions.Comment: 11 pages and 7 figure

Fauna do solo e suas relações com atributos físico-químicos.

Este trabalho objetivou avaliar a diversidade da fauna edáfica e suas relações com os atributos físico-químicos. Foram escolhidas sete áreas, representativas da região Oeste do estado de Santa Catarina (região de Chapecó, SC), abrangendo as seguintes condições de uso: 1) Plantio convencional com rotação de culturas (PCRC1); 2) Plantio direto com rotação de culturas (PDRC2); 3) Plantio convencional com sucessão de cultura (PCSC3); 4) Plantio direto com sucessão de culturas (PDSC4); 5) Cultivo mínimo com sucessão de culturas (CMSC5); 6) Plantio direto com sucessão de culturas (PDSC6) e 7) Plantio direto com sucessão de cultura (PDSC7). Foram analisados nos mesmos pontos de coleta a fauna edáfica e atributos físico-químicos e microbiológicos do solo. Alguns grupos da fauna edáfica apresentaram potencial para serem usados como indicadores da qualidade do solo, pois se mostraram sensíveis ao sistema de preparo e cultivo do solo. Ao considerarmos todos os atributos edáficos, o tratamento PDRC2 ficou mais afastado dos outros com melhores condições físico-químicas e biológicas do solo, em comparação aos demais, especialmente CMSC5 e PDSC6

Determinação de estoques e formas estruturais de carbono em solos sob diversas culturas agrícolas do interior de São Paulo.

Entrada padronizada: BOMFIM, P. F

Evidence for chemical equilibration at RHIC

This contribution focuses on the results of statistical model calculations at RHIC energies, including recently available experimental data. Previous calculations of particle yield ratios showed good agreement with measurements at SPS and lower energies, suggesting that the composite system possesses a high degree of chemical equilibrium at freeze-out. The effect of feeddown contamination on the model parameters is discussed, and the sensitivity of individual ratios to the model parameters ($T$, $\mu_B$) is illustrated.Comment: Talk presented at Strange Quarks in Matter 2001, Frankfurt, September 24-29, 2001. Proceedings to be published by J. Phys. G. 8 pages with 4 figure