Measurement of charm and bottom production in p+p collisions at s\sqrt{s} = 200 GeV at RHIC-PHENIX

RHIC-PHENIX has observed a large suppression pattern and azimuthal anisotropy of non-photonic electron at mid-rapidity ($\mid\eta\mid<0.35$) in Au+Au collisions at $\sqrt{s_{NN}} = 200$ GeV. To understand these results and the interaction of heavy quarks in the hot and dense medium, experimental determination of production ratio of charm over bottom is one of the most important topics, since the behavior of bottom may differ from charm in the medium. We measured the ratio of charm over bottom and total cross section of bottom via partial reconstruction of D$^0$$\to$e$^+$ K$^-$ $\nu_e$ decay in p+p collisions at $\sqrt{s} = 200$ GeV. Total cross sections of charm and bottom were also measured via di-electron continuum in p+p collisions at $\sqrt{s} = 200$ GeV.Comment: 4pages, 4figures,coferenc

System size and beam energy dependence of azimuthal anisotropy from PHENIX

We present azimuthal anisotropy measurements in Au+Au and Cu+Cu collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV. Comparison between reaction plane and cumulant $v_2$ measurements in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV show that non-flow contributions, originating mainly from jets, influence the extracted $v_2$ for $p_T$ $\gtrsim$ 3.5 GeV/c. Number of constituent quark (NCQ) scaling of $v_2$, when studied as a function of transverse kinetic energy $KE_T$, is seen to hold for Au+Au collisions at $\sqrt{s_{NN}}$ = 62.4 and 200 GeV and for Cu+Cu collisions at $\sqrt{s_{NN}}$ = 200 GeV for $KE_{T}$ $\lesssim$ 1 GeV/c. Differential hexadecupole flow $v_4$ seems to exhibit scaling with integral $v_2$ for centrality $\le$ 40% as has been observed for differential $v_2$.Comment: 4 pages, 3 figures, Proceedings of the QM2008 Conference, Jaipur, India February 4-10 200

Measurements of Cold Nuclear Matter Effects on J/psi in the PHENIX Experiment via Deuteron-Gold Collisions

A new calculation of R_{dAu} has been performed using the 2003 d+Au data and the higher-statistics 2005 p+p data. These nuclear modification factors are compared to calculations using nuclear-modified PDFs and a J/psi breakup cross section is extracted. These values are then used to project the cold nuclear matter effects in Au+Au collisions. Additionally, a more data-driven projection is performed.Comment: 4 pages, 6 figures, proceedings for Quark Matter 200

Measurements of heavy quark production via single leptons at PHENIX

The measurement of single leptons from the semi-leptonic decay of heavy-flavor hadrons has long been a means for studying heavy-quark production. PHENIX has measured single muons in pp collisions at forward rapidity and single electrons in both pp and AuAu collisions at mid-rapidity at sqrt(s_NN)=200 GeV. The most recent PHENIX single lepton results are presented in the context of state-of-the-art pQCD calculations. An updated azimuthal anisotropy, v2(pT), measurement for heavy-flavor single electrons in AuAu collisions is also presented.Comment: 4 pages, 4 figures, presented at the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions, "Quark Matter 2008", Jaipur, India, February 4-10, 200

Identified Particle Jet Correlations from PHENIX

Two-particle azimuthal correlations have been shown to be a powerful probe for extracting novel features of the interaction between hard scattered partons and the medium produced in Au+Au collisions at RHIC. At intermediate $p_T$, 2-5GeV/c, jets have been shown to be significantly modified in both particle composition and angular distribution compared to p+pcollisions. We present recent PHENIX results from Au+Au collisions for a variety of $p_T$ and particle combinations.Comment: Parallel talk given at Quark Matter 2006, Shanghai Chin

Hair arsenic level in rice-based diet-fed Staffordshire bull terriers

Background: There have been concerns related to inorganic arsenic (iAs) in rice and the risk of chronic toxicity in human beings, especially children. Rice is a common constituent of pet food, and dogs often eat the same food on a continual daily basis for long periods of time. Therefore, the purpose of this study was to assess the risk of chronic iAs exposure in rice-based diet-fed dogs. Methods: Hair iAs level was measured in seven rice-based diet-fed dogs (mean age 3.8 years) and in nine dogs that did not consume any rice (mean age 4.4 years), using inductively coupled plasma mass spectrometry. Results: The hair iAs level was significantly higher (P=0.005) in dogs fed a rice-based diet (mean 0.143 µg/g) than in dogs that did not consume any rice (mean 0.086 µg/g), while age and sex did not show associations with hair iAs level. Conclusion: The results suggest that eating a rice-based diet for long periods of time represents a risk for chronic iAs exposure in dogs.Peer reviewe

PHENIX measurement of jet properties and their modification in heavy-ion collisions

The properties of jets produced in p+p, d+Au and Au+Au collisions at sqrt{s_NN}=200 GeV are studied using the method of two particle correlations. The trigger particle is assumed to be a leading particle from a high p_T jet while the associated particle is assumed to come from either the same jet or the away jet. From the angular width and yield of the same and away side correlation peaks, the parameters characterizing the jet properties are extracted.Comment: 4 pages, 3 figures, contribution to the proceedings of the 17th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter, Oakland, January 11-17, 2004). To appear in the proceedings (Journal of Physics G

Hadron production in the forward and backward rapidities in dAu collisions at RHIC

We have developed new techniques to detect hadrons with the PHENIX muon spectrometers. This allows us to study the centrality dependent nuclear modification factor $R_{CP}$ with high $p_{T}$ hadrons in both forward (d direction) and backward (Au direction) rapidities, $1 < |\eta| < 2$, in dAu collisions at $\sqrt{s_{NN}} = 200 GeV$. Preliminary results show a suppression (enhancement) of high $p_{T}$ hadron production in central $0-20$ dAu collisions relative to the peripheral one ($60-88$ in centrality) at forward (backward) rapidity.Comment: 4 pages, 4 figures, Quark Matter 2004 tal

Highlights from PHENIX - I

This contribution highlights recent results from the PHENIX Collaboration at RHIC. It covers global variables, flow and 2--particle correlations. A second contribution in this issue, by T.C.Awes, covers PHENIX results on heavy quarks, leptons and photons.Comment: Contribution to the 2008 Quark Matter Conference, Jaipur India Sumbitted to Journal of Physics G: Nuclear and Particle Physic

Diet and dog characteristics affect major and trace elements in hair and blood of healthy dogs

Obtaining correct amounts of essential elements, and avoiding toxic metals are key factors in dog health. Through analyzing major and trace elements in hair and blood of 50 healthy companion dogs using ICP-MS, we study their associations with dog characteristics and diet, hypothesizing that eating the same diet long-term results in strong correlations between hair and blood element concentrations, and that dog characteristics and diet affect element status. The correlation between hair and blood was significant for Hg (R = 0.601, p = 0.000) and Pb (R = 0.384, p = 0.010). The following associations were significant (p < 0.05): Dark hair had higher Ca and Mg compared to light hair. Females had higher hair Zn, blood Mn, and blood As compared to males. Blood Mn and Se increased, while blood Pb decreased with age. Raw diet fed dogs had higher hair Zn and Se compared to dry or mixed diet fed dogs, and lower blood Mn compared to dry diet fed dogs. Dry and mixed diet fed dogs had higher blood Cd compared to raw diet fed dogs. Mixed diet fed dogs had higher hair Ca and Mg compared to raw or dry diet fed dogs, and higher hair Pb compared to dry diet fed dogs. Wild game consumption was associated with higher blood Pb, and rice consumption with higher blood As. In conclusion, hair provides an alternative for assessing Hg and Pb exposure, and major and trace elements status is affected by hair color, sex, age, and diet.Peer reviewe