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We present the first measurements of long-range angular correlations and the transverse momentum dependence of elliptic flow v2 in high-multiplicity p+Au collisions at √ s N N = 200 GeV. A comparison of these results with previous measurements in high-multiplicity d+Au and 3 He+Au collisions demonstrates a relation between v2 and the initial collision eccentricity ε2, suggesting that the observed momentum-space azimuthal anisotropies in these small systems have a collective origin 3 and reflect the initial geometry. Good agreement is observed between the measured v2 and hydrodynamic calculations for all systems, and an argument disfavoring theoretical explanations based on initial momentum-space domain correlations is presented. The set of measurements presented here allows us to leverage the distinct intrinsic geometry of each of these systems to distinguish between different theoretical descriptions of the long-range correlations observed in small collision systems.

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Recently, multiparticle-correlation measurements of relativistic p/d/^{3}He+Au, p+Pb, and even p+p collisions show surprising collective signatures. Here, we present beam-energy-scan measurements of two-, four-, and six-particle angular correlations in d+Au collisions at sqrt[s_{NN}]=200, 62.4, 39, and 19.6 GeV. We also present measurements of two- and four-particle angular correlations in p+Au collisions at sqrt[s_{NN}]=200  GeV. We find the four-particle cumulant to be real valued for d+Au collisions at all four energies. We also find that the four-particle cumulant in p+Au has the opposite sign as that in d+Au. Further, we find that the six-particle cumulant agrees with the four-particle cumulant in d+Au collisions at 200 GeV, indicating that nonflow effects are subdominant. These observations provide strong evidence that the correlations originate from the initial geometric configuration, which is then translated into the momentum distribution for all particles, commonly referred to as collectivity.

This study evaluated the effects of placebo medication on pulmonary responses in asthmatics, and investigated the roles of expectancy and anxiety. Twelve adult asthmatics were recruited for a laboratory experiment described as a study of the effectiveness of a new bronchodilator. Distilled nebulized water was inhaled in each session. The solution was described as water in session 1 (control), while in sessions 2 and 3 subjects were told that the nebulizer contained a chemical likely to cause chest tightness and wheezing (bronchoconstrictive suggestion). Prior to the inhalation sequence in sessions 2 and 3, subjects inhaled from an aerosol that they were told contained either a powerful new drug (placebo) or a non-active substance (neutral). Pulmonary function was measured with the forced oscillation technique and spirometry, while autonomic parameters, anxiety and expectancies were also monitored. Pulmonary function deteriorated following the inhalations accompanied by bronchoconstrictive suggestion, and this effect was abolished by pre-treatment with placebo. Neither subject expectations nor changes in anxiety were associated with the experimental manipulations. The implications of these results for theories of placebo action are considered.