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

Desempenho de bovinos cruzados, machos não castrados e fêmeas, terminados em confinamento.

O objetivo deste trabalho foi avaliar o desempenho em confinamento de 27 machos não castrados e 31 fêmeas filhos de vacas ½ Angus x ½ Nelore e vacas ½ Simental x ½ Nelore, inseminadas com sêmen de touros das raças Angus e Limousin. Os animais foram mantidos em baias individuais descobertas com consumo ad libitum. Os machos apresentaram maior peso (P≤0,05) vivo inicial e final (242,4 e 450,4 kg, respectivamente), quando comparados às fêmeas (221,6 e 374,6 kg, respectivamente). O ganho médio diário de peso dos machos (1,579 kg) foi maior (P≤0,05) que o das fêmeas (1,226 kg). A conversão alimentar foi de 6,455 kg/kg para machos e de 7,282 kg/kg para fêmeas. Os machos apresentaram maior média (P≤0,05) de rendimento de carcaça quente do que as fêmeas (57,25% e 54,93%, respectivamente). Todos os cruzamentos avaliados possibilitaram o abate dos animais aos 12 meses de idade, independentemente do sexo.Disponivel tb em: In: JORNADA CIENTÍFICA - EMBRAPA SÃO CARLOS, 4., 2012, São Carlos, SP. Anais... São Carlos: Embrapa Instrumentação Agropecuária: Embrapa Pecuária Sudeste, 2012. (Embrapa Instrumentação Agropecuária. Documentos ?). No prel

K*(892)0 Production in Relativistic Heavy Ion Collisions at sqrt(s_NN) = 130 GeV

Preliminary results on the K*(892)0 -> pi + K production using the mixed-event technique are presented. The measurements are performed at mid-rapidity by the STAR detector in sqrt(s_NN) = 130 GeV Au-Au collisions at RHIC. The K*0 to negative hadron, kaon and phi ratios are obtained and compared to the measurements in e+e-, pp and pbarp at various energies.Comment: 8 pages, 3 figures, proceedings of Strange Quarks in Matter (SQM2001), Frankfurt am Main, Germany, to be published in J. Phys.

Resonance Production

Recent results on rho(770)^0, K(892)^*0, f_0(980), phi(1020), Delta(1232)^++, and Lambda(1520) production in A+A and p+p collisions at SPS and RHIC energies are presented. These resonances are measured via their hadronic decay channels and used as a sensitive tool to examine the collision dynamics in the hadronic medium through their decay and regeneration. The modification of resonance mass, width, and shape due to phase space and dynamical effects are discussed.Comment: 8 pages, 10 figures, proceedings of the Quark Matter 2004, in Oakland, California, to be published in Journal of Physics G: Nuclear and Particle Physic

A microscopic approach to heating rate of ferrofluid droplets by a magnetic field

CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORIn this work, we study the heating process of colloidal ferrofluids by a magnetic field. The heating of the fluid occurs by the magnetic relaxation of the nanoparticles which provide thermal energy for the host liquid. In the limit of small volumes, the relaxation process occurs through the Neel mechanism since the magnetic nanoparticles present superparamagnetic behavior. Within this limit, we have used a microscopic model for the coupling to phonons and external magnetic field in order to model the relaxation mechanism and to obtain an expression for the heating rate of the fluid as a function of microscopic parameters. The analysis allows determining appropriate conditions for an optimal heating rate for ferrofluids based on superparamagnetic nanoparticles.1254111CNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIOR307466/2016-7PNPD 028/2010E.C.S. acknowledges support from the CNPq agency under Grant No. 307466/2016-7. P.A.O. acknowledges financial support from FONDECYT under Grant No. 1140571. F.F.F. and E.C.S. acknowledge CAPES agency financial support (No. CAPES PNPD 028/2010)

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

Entrada padronizada: BOMFIM, P. F

K∗(892)K^{*}(892) Production in Au+Au and pp Collisions at sNN\sqrt{s_{NN}} = 200GeV at STAR

Mid-rapidity $K^{*0}(892)\to K\pi$ and $K^{*\pm}(892)\to K_S^0\pi^{\pm}$ are measured in Au+Au and pp collisions at $\sqrt{s_{NN}}$=200GeV using the STAR detector at RHIC. The $K^{*0}(892)$ mass is systematically shifted at small transverse momentum for both Au+Au and pp collisions. The $K^{*0}(892)$ transverse mass spectra are measured in Au+Au collisions at different centralities and in pp collisions. The $K^{*0}(892)$ mean transverse momentum as a function of the collision centrality is compared to those of identified $\pi^{-}$, $K^{-}$ and $\bar{p}$. The $K^{*}/K$ and $\phi/K^{*}$ ratios are compared to measurements in A+A, $pp$, $\bar{p}p$, $e^{+}e^{-}$ collisions at various colliding energies. The physics implications of these measurements are also discussed.Comment: 6 pages, 4 figures, proceedings of Strange Quarks in Matter (SQM2003), Atlantic Beach, USA, to be published in J. Phys.

Dileptons and Medium Effects in Heavy-Ion Collisions

We discuss the status of calculating in-medium modifications of vector-meson spectral functions in hot and dense matter, their application to dilepton spectra in ultrarelativistic heavy-ion collisions, and possible relations to chiral symmetry restoration. We emphasize the importance of constraining in-medium spectral functions by empirical information from scattering data, QCD sum rules, and lattice QCD. This is a mandatory prerequisite to arrive at reliable predictions for low-mass dileptons in heavy-ion collisions.Comment: 8 pages latex, 15 figure

Thermal analysis of production of resonances in relativistic heavy-ion collisions

Production of resonances is considered in the framework of the single-freeze-out model of ultra-relativistic heavy ion collisions. The formalism involves the virial expansion, where the probability to form a resonance in a two-body channel is proportional to the derivative of the phase-shift with respect to the invariant mass. The thermal model incorporates longitudinal and transverse flow, as well as kinematic cuts of the STAR experiment at RHIC. We find that the shape of the pi+ pi- spectral line qualitatively reproduces the preliminary experimental data when the position of the rho peak is lowered. This confirms the need to include the medium effects in the description of the RHIC data. We also analyze the transverse-momentum spectra of rho, K*(892), and f_0(980), and find that the slopes agree with the observed values. Predictions are made for eta, eta', omega, phi, Lambda(1520), and Sigma(1385).Comment: minor modifications, a reference adde