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A preliminary analysis has recorded the cushion lifeform in 60 taxa from lowland southern Australia (i.e. latitudes south of 26° S) encompassing six morphological forms from open, non-peat-accumulating species (58 taxa) to hard, dense cushions more typical of alpine and subalpine areas (2 taxa). Only two species appear to be obligate cushions. All but six cushion-forming species are endemic to southern Western Australia. Most species occur in the Transitional Rainfall Zone rather than the High Rainfall Zone or the more arid interior, with only one species being endemic to the arid zone. In Western Australia cushion-forming species occur on exposed coasts, granites, edges of salt lakes and sandplains; almost half of the species also commonly occur across a number of other habitat types. The few plant communities dominated by cushion plants are generally restricted to small areas of a specific habitat type such as Borya herblands on shallow soils around outcropping granites. Lowland cushion species in Western Australia do not appear to be restricted to the most stressful habitats.
We report on a polarization measurement of inclusive J/ψ mesons in the di-electron decay channel at mid-rapidity at 2 < pT < 6 GeV/c in p + p collisions at √s = 200 GeV. Data were taken with the STAR detector at RHIC. The J/ψ polarization measurement should help to distinguish between different models of the J/ψ production mechanism since they predict different pT dependences of the J/ψ polarization. In this analysis, J/ψ polarization is studied in the helicity frame. The polarization parameter λθ measured at RHIC becomes smaller towards high pT , indicating more longitudinal J/ψ polarization as pT increases. The result is compared with predictions of presently available models.
A data-driven method was applied to Au+Au collisions at √sNN = 200 GeV made with the STAR detector at RHIC to isolate pseudorapidity distance η-dependent and η-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a η-independent component of the correlation, which is dominated by anisotropic flow and flow fluctuations. It was also found to be independent of η within the measured range of pseudorapidity |η| < 1. In 20–30% central Au+Au collisions, the relative flow fluctuation was found to be 34%±2%(stat.)±3%(sys.) for particles with transverse momentum pT less than 2 GeV/c. The η-dependent part, attributed to nonflow correlations, is found to be 5% ± 2%(sys.) relative to the flow of the measured second harmonic cumulant at |η| > 0.7.