J/ψ\rm{J}/\psi production at low transverse momentum in p+p and d+Au collisions at sNN\sqrt{s_{NN}} = 200 GeV

We report on the measurement of $\rm{J}/\psi$ production in the dielectron channel at mid-rapidity (|y|<1) in p+p and d+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV from the STAR experiment at the Relativistic Heavy Ion Collider. The transverse momentum $p_{T}$ spectra in p+p for $p_{T}$ < 4 GeV/c and d+Au collisions for $p_{T}$ < 3 GeV/c are presented. These measurements extend the STAR coverage for $\rm{J}/\psi$ production in p+p collisions to low $p_{T}$. The $$ from the measured $\rm{J}/\psi$ invariant cross section in p+p and d+Au collisions are evaluated and compared to similar measurements at other collision energies. The nuclear modification factor for $\rm{J}/\psi$ is extracted as a function of $p_{T}$ and collision centrality in d+Au and compared to model calculations using the modified nuclear Parton Distribution Function and a final-state $\rm{J}/\psi$ nuclear absorption cross section

Measurement of the flavour composition of dijet events in pp collisions at root s=7 TeV with the ATLAS detector

This paper describes a measurement of the flavour composition of dijet events produced in pp collisions at &#8730;s=7 TeV using the ATLAS detector. The measurement uses the full 2010 data sample, corresponding to an integrated luminosity of 39 pb−1. Six possible combinations of light, charm and bottom jets are identified in the dijet events, where the jet flavour is defined by the presence of bottom, charm or solely light flavour hadrons in the jet. Kinematic variables, based on the properties of displaced decay vertices and optimised for jet flavour identification, are used in a multidimensional template fit to measure the fractions of these dijet flavour states as functions of the leading jet transverse momentum in the range 40 GeV to 500 GeV and jet rapidity |y|&#60;2.1. The fit results agree with the predictions of leading- and next-to-leading-order calculations, with the exception of the dijet fraction composed of bottom and light flavour jets, which is underestimated by all models at large transverse jet momenta. The ability to identify jets containing two b-hadrons, originating from e.g. gluon splitting, is demonstrated. The difference between bottom jet production rates in leading and subleading jets is consistent with the next-to-leading-order predictions

Di-hadron correlations with identified leading hadrons in 200 GeV Au+Au and d+Au collisions at STAR

The STAR Collaboration presents for the first time two-dimensional di-hadron correlations with identified leading hadrons in 200 GeV central Au + Au and minimum-bias d + Au collisions to explore hadronization mechanisms in the quark gluon plasma. The enhancement of the jet-like yield for leading pions in Au + Au data with respect to the d + Au reference and the absence of such an enhancement for leading non-pions (protons and kaons) are discussed within the context of a quark recombination scenario. The correlated yield at large angles, specifically in the ridge region , is found to be significantly higher for leading non-pions than pions. The consistencies of the constituent quark scaling, azimuthal harmonic model and a mini-jet modification model description of the data are tested, providing further constraints on hadronization

Pro. cardiovascular calcifications are clinically relevant

It is increasingly acknowledged that mineral and bone disorders (MBDs) contribute to the excessively high cardiovascular (CV) disease morbidity and mortality observed in patients with chronic kidney disease (CKD). There is ongoing debate as to whether screening for CV calcification, one of the hallmarks of CKD-MBD, should be implemented in clinical practice in patients with CKD. Issues to be considered in this controversy relate to prevalence, severity, relevance, and last but not least, modifiability and reversibility of vascular and valvular calcifications in the setting of CKD. The recent expansion of the armamentarium to treat CKD-MBD (calcium-free phosphate binders and calcimimetics) creates new opportunities. Mounting experimental and clinical evidence indicates that progression of CV calcification may indeed be attenuated. Whether this will translate into better outcomes remains to be proven. We acknowledge that hard outcome data so far are limited and, overall, yielded inconclusive results. Nevertheless, in an era in which personalized medicine has gained much popularity, we consider it reasonable, awaiting the results of additional studies, to screen for CV calcification in selected individuals. This policy may help to stratify CV risk and to guide therapy. We speculate that such an approach will ultimately improve outcomes and reduce health costs

Properties of Events With Large Total Transverse Energy Produced In Proton-antiproton Collisions At Square-root-s = 1.8 Tev

The properties of proton-antiproton interactions in which the total transverse energy exceeds 400 GeV are described. These events have been recorded at the Fermilab Tevatron collider operating at a center-of-mass energy of 1.8 TeV. The differential cross section, jet rates, jet transverse-momentum and pseudorapidity distributions, single-jet shapes, and the multijet rates and kinematics are compared with QCD predictions. There is no evidence for a significant deviation from standard-model expectations that would be signaled by the presence of an excess of isolated high-transverse-momentum leptons or photons, or an excess of events with unusual jet rates or characteristics

Measurement of elliptic flow of light nuclei at sNN =200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV at the BNL Relativistic Heavy Ion Collider

We present measurements of second-order azimuthal anisotropy (v2) at midrapidity (|y|<1.0) for light nuclei d,t,He3 (for sNN=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV) and antinuclei d\uaf (sNN=200, 62.4, 39, 27, and 19.6 GeV) and He\uaf3 (sNN=200 GeV) in the STAR (Solenoidal Tracker at RHIC) experiment. The v2 for these light nuclei produced in heavy-ion collisions is compared with those for p and p\uaf. We observe mass ordering in nuclei v2(pT) at low transverse momenta (pT<2.0 GeV/c). We also find a centrality dependence of v2 for d and d\uaf. The magnitude of v2 for t and He3 agree within statistical errors. Light-nuclei v2 are compared with predictions from a blast-wave model. Atomic mass number (A) scaling of light-nuclei v2(pT) seems to hold for pT/A<1.5GeV/c. Results on light-nuclei v2 from a transport-plus-coalescence model are consistent with the experimental measurements

Probing parton dynamics of QCD matter with \u3a9 and \u3c6 production

We present measurements of \u3a9 and \u3d5 production at midrapidity from Au+Au collisions at nucleon-nucleon center-of-mass energies sNN=7.7, 11.5, 19.6, 27, and 39 GeV by the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). Motivated by the coalescence formation mechanism for these strange hadrons, we study the ratios of N(\u3a9 12+\u3a9\uaf+)/[2N(\u3d5)]. These ratios as a function of transverse momentum pT fall on a consistent trend at high collision energies, but start to show deviations in peripheral collisions at sNN=19.6, 27, and 39 GeV, and in central collisions at 11.5 GeV in the intermediate pT region of 2.4 123.6 GeV/c. We further evaluate empirically the strange quark pT distributions at hadronization by studying the \u3a9/\u3d5 ratios scaled by the number of constituent quarks (NCQ). The NCQ-scaled \u3a9/\u3d5 ratios show a suppression of strange quark production in central collisions at 11.5 GeV compared to sNN 6519.6 GeV. The shapes of the presumably thermal strange quark distributions in 0\u201360% most central collisions at 7.7 GeV show significant deviations from those in 0\u201310% most central collisions at higher energies. These features suggest that there is likely a change of the underlying strange quark dynamics in the transition from quark matter to hadronic matter at collision energies below 19.6 GeV

MEASUREMENT OF W-PHOTON COUPLINGS IN P-(P)OVER-BAR COLLISIONS AT ROOT-S=1.8 TEV

We report on a study of W + photon production in approximately 20 pb-1 of p-p collisions at s=1.8 TeV recorded with the Collider Detector at Fermilab. Our results are in good agreement with standard model expectations and are used to obtain limits on anomalous CP-conserving WW couplings of -2.3&lt;&lt;2.2 for =0 and -0.7&lt;&lt;0.7 for =0 at 95% C.L. We obtain the same limits for CP-violating couplings. These results provide limits on the higher-order electromagnetic moments of the W boson of 0.