Suppression of Upsilon production in d plus Au and Au plus Au collisions at root S-NN=200 GeV

We report measurements of Upsilon meson production in p + p, d + Au, and Au + Au collisions using the STAR detector at RHIC. We compare the Upsilon yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au + Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in the rapidity range vertical bar y vertical bar < 1 in d + Au collisions of R-dAu = 0.79 +/- 0.24(stat.) +/- 0.03(syst.) +/- 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R-AA = 0.49 +/- 0.1(stat.) +/- 0.02(syst.) +/- 0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark-Gluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made735127137CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPRHIC Operations Group; NERSC Center at LBNL; KISTI Center in Korea; Open Science Grid consortium; National Science Foundation (NSF); Centre National de la Recherche Scientifique (CNRS); Ministry of Education and Science, Russian Federation; National Natural Science Foundation of China (NSFC); Chinese Academy of Sciences; Korean Research Foundation, GA; Ministry of Education, Youth & Sports - Czech Republic; FIAS of Germany; Department of Atomic Energy (DAE); Department of Science & Technology (India); Council of Scientific & Industrial Research (CSIR) - India; National Science Center, Poland; RosAtom of Russia ; RCF at BNL; United States Department of Energy (DOE); United States Department of Energy (DOE); Ministry of Education, China; Ministry of Science and Technology, China; Ministry of Science, Education and Sports, Republic of Croatia; National Science Foundation (NSF); NSF - Directorate for Mathematical & Physical Sciences (MPS

Beam Energy Dependence of Moments of the Net-Charge Multiplicity Distributions in Au plus Au Collisions at RHIC

We report the first measurements of the moments-mean (M), variance (sigma(2)), skewness (S), and kurtosis (kappa)-of the net-charge multiplicity distributions at midrapidity in Au + Au collisions at seven energies, ranging from root s(NN) = 7.7 to 200 GeV, as a part of the Beam Energy Scan program at RHIC. The moments are related to the thermodynamic susceptibilities of net charge, and are sensitive to the location of the QCD critical point. We compare the products of the moments, sigma(2)/M, S sigma, and kappa sigma(2), with the expectations from Poisson and negative binomial distributions (NBDs). The S sigma values deviate from the Poisson baseline and are close to the NBD baseline, while the kappa sigma(2) values tend to lie between the two. Within the present uncertainties, our data do not show nonmonotonic behavior as a function of collision energy. These measurements provide a valuable tool to extract the freeze-out parameters in heavy-ion collisions by comparing with theoretical models

Intermediate Point Norm Optimal Iterative Learning Control

A Norm-Optimal Iterative Learning Control (NOILC) solution is developed for the problem when tracking is only required at a subset of isolated time points along the trial duration. Well-defined convergence properties are presented, along with design guidelines and supporting experimental results using an electromechanical test facility

An evaluation of the knowledge and needs of women with diabetes in relation to reproductive health; a focus group study

see paper for full list of authorsJet-medium interactions are studied via a multi-hadron correlation technique (called "2+1"), where a pair of back-to-back hadron triggers with large transverse momentum is used as a proxy for a di-jet. This work extends the previous analysis for nearly-symmetric trigger pairs with the highest momentum threshold of trigger hadron of 5 GeV/$c$ with the new calorimeter-based triggers with energy thresholds of up to 10 GeV and above. The distributions of associated hadrons are studied in terms of correlation shapes and per-trigger yields on each trigger side. In contrast with di-hadron correlation results with single triggers, the associated hadron distributions for back-to-back triggers from central Au+Au data at $\sqrt{s_{NN}}$=200 GeV show no strong modifications compared to d+Au data at the same energy. An imbalance in the total transverse momentum between hadrons attributed to the near-side and away-side of jet-like peaks is observed. The relative imbalance in the Au+Au measurement with respect to d+Au reference is found to increase with the asymmetry of the trigger pair, consistent with expectation from medium-induced energy loss effects. In addition, this relative total transverse momentum imbalance is found to decrease for softer associated hadrons. Such evolution indicates the energy missing at higher associated momenta is converted into softer hadrons

Observation of an Antimatter Hypernucleus

Nuclear collisions recreate conditions in the universe microseconds after the Big Bang. Only a very small fraction of the emitted fragments are light nuclei, but these states are of fundamental interest. We report the observation of antihypertritons-comprising an antiproton, an antineutron, and an antilambda hyperon-produced by colliding gold nuclei at high energy. Our analysis yields 70 +/- 17 antihypertritons (3/Lambda(H) over bar) and 157 +/- 30 hypertritons (H-3(Lambda)). The measured yields of H-3(Lambda) (3/Lambda(H) over bar) and He-3 ((3)(He) over bar) are similar, suggesting an equilibrium in coordinate and momentum space populations of up, down, and strange quarks and antiquarks, unlike the pattern observed at lower collision energies. The production and properties of antinuclei, and of nuclei containing strange quarks, have implications spanning nuclear and particle physics, astrophysics, and cosmology

Event-plane-dependent dihadron correlations with harmonic v(n) subtraction in Au plus Au collisions at v root sNN=200 GeV

STAR measurements of dihadron azimuthal correlations (Lambda phi) are reported in midcentral (20-60%) Au + Au collisions at v root sNN = 200 GeV as a function of the trigger particle's azimuthal angle relative to the event plane, phi(s) = | phi(1) -psi(EP)|. The elliptic (v(2)), triangular (v(3)), and quadratic (v(4)) flow harmonic backgrounds are subtracted using the zero yield at mini + Au collisions. It is found that a finite near-side (| Delta phi | pi/2) correlation shows a modification from d+ Au data, varying with fs. The modification may be a consequence of path-length-dependent jet quenching and may lead to a better understanding of high-density QCD

J/psi production at high transverse momenta in p plus p and Au plus Au collisions at root s(NN)=200 GeV

We report J/psi spectra for transverse momenta P-T > 5 GeV/c at mid-rapidity in p + p and Au + Au collisions at root s(NN) = 200 GeV. The inclusive J/psi spectrum and the extracted B-hadron feed-down are compared to models incorporating different production mechanisms. We observe significant suppression of the J/psi yields for p(T) > 5 GeV/c in 0-30% central Au + Au collisions relative to the p + p yield scaled by the number of binary nucleon-nucleon collisions in Au + Au collisions. In 30-60% mid-central collisions, no such suppression is observed. The level of suppression is consistently less than that of high-p(T) pi(+/-) and low-p(T) J/psi at RHIC and high-p(T) J/psi at the LHC. (C) 2013 Elsevier B.V. All rights reserved

J/psi production at high transverse momenta in p plus p and Au plus Au collisions at root s(NN)=200 GeV

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We report J/psi spectra for transverse momenta P-T > 5 GeV/c at mid-rapidity in p + p and Au + Au collisions at root s(NN) = 200 GeV. The inclusive J/psi spectrum and the extracted B-hadron feed-down are compared to models incorporating different production mechanisms. We observe significant suppression of the J/psi yields for p(T) > 5 GeV/c in 0-30% central Au + Au collisions relative to the p + p yield scaled by the number of binary nucleon-nucleon collisions in Au + Au collisions. In 30-60% mid-central collisions, no such suppression is observed. The level of suppression is consistently less than that of high-p(T) pi(+/-) and low-p(T) J/psi at RHIC and high-p(T) J/psi at the LHC. (C) 2013 Elsevier B.V. All rights reserved.722416995562RHIC Operations Group and RCF at BNLNERSC Center at LBNLOpen Science Grid consortiumOffices of NP and HEP within the US DOE Office of ScienceUS NSFSloan FoundationDFG cluster of excellence 'Origin and Structure of the Universe' of GermanyCNRS/IN2P3Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Ministry of Ed. and Sci. of the Russian FederationNNSFCCASMoSTMoE of ChinaGAMSMT of the Czech RepublicFOMNWO of the NetherlandsDAEDSTCSIR of IndiaPolish Ministry of Sci. and Higher Ed.Korea National Research FoundationMinistry of Sci., Ed. and Sports of the Rep. of CroatiaRosAtom of RussiaFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Fluctuations of charge separation perpendicular to the event plane and local parity violation in root S-NN=200 GeV Au + Au collisions at the BNL Relativistic Heavy Ion Collider

Previous experimental results based on data (similar to 15 x 10(6) events) collected by the STAR detector at the BNL Relativistic Heavy Ion Collider suggest event-by-event charge-separation fluctuations perpendicular to the event plane in noncentral heavy-ion collisions. Here we present the correlator previously used split into its two component parts to reveal correlations parallel and perpendicular to the event plane. The results are from a high-statistics 200-GeV Au + Au collisions data set (57 x 10(6) events) collected by the STAR experiment. We explicitly count units of charge separation from which we find clear evidence for more charge-separation fluctuations perpendicular than parallel to the event plane. We also employ a modified correlator to study the possible P-even background in same- and opposite-charge correlations, and find that the P-even background may largely be explained by momentum conservation and collective motion