[en] We present results on charged particle (((dN_ch)/(dη))) and transverse energy densities (((E_T)/(dη))) measured at mid-rapidity in Au-Au collisions at √s_NN=200 GeV. The mean transverse energy per charged particle is derived. The results are presented as a function of centrality, which is defined by the number of participating nucleons (N_p), and compared to results obtained in Au-Au collisions at √s_NN=130 GeV. A comparison with calculations from various theoretical models is performed

[en] We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the polarization-weighted luminosity (figure of merit) in single and double spin measurements in colliding beam experiments. Applications to RHIC are discussed.

[en] The Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory (BNL) was commissioned for polarized proton-proton collisions, at the center of mass energy √s = 200 GeV during the run in 2001-2002. The authors have measured the single transverse-spin asymmetry A_N for production of photons, neutral pions, and neutrons at the very forward angle. The asymmetries for the photon and neutral pion sample were consistent with zero within the experimental uncertainties. In contrast, the neutron sample exhibited an unexpectedly large asymmetry. This large asymmetry will be used for the non-destructive polarimeter for polarized proton beams at the collision points in the RHIC interaction region

[en] This volume archives the presentations at the RIKEN BNL Research Center workshop 'Progress in High-PT Physics at RHIC', held at BNL in March 2010. Much has been learned from high-p_T physics after 10 years of RHIC operations for heavy-ion collisions, polarized proton collisions and d+Au collisions. The workshop focused on recent progress in these areas by both theory and experiment. The first morning saw review talks on the theory of RHIC high-p_T physics by G. Sterman and J. Soffer, and on the experimental results by M. Tannenbaum. One of the most exciting recent results from the RHIC spin program is the first observation of W bosons and their associated single-spin asymmetry. The new preliminary data were reported on the first day of our workshop, along with a theoretical perspective. There also were detailed discussions on the global analysis of polarized parton distributions, including the knowledge on gluon polarization and the impact of the W-data. The main topic of the second workshop day were single-transverse spin asymmetries and their analysis in terms of transverse-momentum dependent parton distributions. There is currently much interest in a future Drell-Yan program at RHIC, thanks to the exciting physics opportunities this would offer. This was addressed in some of the talks. There also were presentations on the latest results on transverse-spin physics from HERMES and BELLE. On the final day of the workshop, the focus shifted toward forward and small-x physics at RHIC, which has become a cornerstone of the whole RHIC program. Exciting new data were presented and discussed in terms of their possible implications for our understanding of strong color-field phenomena in QCD. In the afternoon, there were discussions of nuclear parton distributions and jet observables, among them fragmentation. The workshop was concluded with outlooks toward the near-term (LHC, JLab) and longer-term (EIC) future. The workshop has been a great success. We had excellent presentations throughout and productive discussions, which showed the importance and unique value of the RHIC high-p_T program. We are grateful to all participants for coming to BNL. The support provided by the RIKEN-BNL Research Center for this workshop has been magnificent, and we are most grateful for it. We also thank Brookhaven National Laboratory and the U.S. Department of Energy for providing additional support and for the facilities to hold this workshop. Finally, sincere thanks go to Pamela Esposito for her most efficient and tireless work in organizing and running the workshop.

[en] The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized protons. During beam acceleration and storage profiles of the polarization P develop, which affect the polarization measured in a polarimeter, and the polarization and figure of merit (FOM) in colliding beam experiments. We calculate these for profiles in all dimensions, and give examples for RHIC. Like in RHIC we call the two colliding beams Blue and Yellow. We use the overbar to designate intensity-weighted averages in polarimeters (e.g. (bar P)), and angle brackets to designate luminosity-weighted averages in colliding beam experiments (e.g. < P>).

[en] Acceleration of polarized protons in Relativistic Heavy Ion Collider (RHIC) provides unique tool to study the spin structure of the nucleon. We give a brief overview of the PHENIX program to investigate poorly known gluon and flavor decomposed see quark polarization in the proton, utilizing polarized proton collisions at RHIC. We report PHENIX first results on transverse single-spin asymmetry in π⁰ and charged hadron production and longitudinal double-spin asymmetry in π⁰ production at mid-rapidity. (author)

[en] The polarized pp collisions at RHIC provide very good opportunity to study the structure of the nucleon. Prompt photons are a good probe to measure the gluon density. The main background comes from two photon decays of π⁰ 's and η 's. An electromagnetic calorimeter (EMCal) in PHENIX plays the key role for both prompt photon reconstruction and background suppression. A study based on PYTHIA event generator and EMCal response parameterization including γ/π⁰ and electromagnetic/hadronic shower discrimination is presented. (author)

[en] We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the polarization-weighted luminosity (figure of merit) in single and double spin measurements in colliding beam experiments.

[en] Acceleration of polarized protons in Relativistic Heavy Ion Collider (RHIC) will provide unique tool to study spin structure of the nucleon, covering the √s region from 50 GeV to 500 GeV with proton polarization of 70%. PHENIX, one of the major detector systems at RHIC, is going to investigate poorly known gluon and flavor identified sea quark polarization in the proton. Overview of the RHENIX spin program is presented and sensitivities of the measurements are discussed

[en] We present PHENIX recent results on charged particle and transverse energy densities measured at mid-rapidity in Au-Au collisions at √S_NN = 130 GeV and 200 GeV over a broad range of centralities. The mean transverse energy per charged particle is derived. The first PHENIX measurements at √S_NN = 19.6 GeV are also presented. A comparison with calculations from various theoretical models is performed. (author)