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1.	Adcox, K, et al. (författare) PHENIX detector overview 2003 Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479 Tidskriftsartikel (refereegranskat)abstract The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
2.	Adloff, C, et al. (författare) Measurement of inclusive jet cross-sections in deep-inelastic ep scattering at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 542:3-4, s. 193-206 Tidskriftsartikel (refereegranskat)abstract A measurement of inclusive jet cross-sections in deep-inelastic ep scattering at HERA is presented based on data with an integrated luminosity of 21.1 pb(-1). The measurement is performed for photon virtualities Q(2) between 5 and 100 GeV2, differentially in Q(2), in the jet transverse energy E-T, in E-T(2)/Q(2) and in the pseudorapidity eta(lab). With the renormalization scale mu(R) = E-T, perturbative QCD calculations in next-to-leading order (NLO) give a good description of the data in most of the phase space. Significant discrepancies are observed only for jets in the proton beam direction with ET below 20 GeV and Q2 below 20 GeV2. This corresponds to the region in which NLO corrections are largest and further improvement of the calculations is thus of particular interest.
3.	Adloff, C, et al. (författare) A measurement of the t dependence of the helicity structure of diffractive rho meson electroproduction at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 539:1-2, s. 25-39 Tidskriftsartikel (refereegranskat)abstract The helicity structure of the diffractive electroproduction of rho mesons, e + p --> e + rho + Y, is studied in a previously unexplored region of large four-momentum transfer squared at the proton vertex, t: 0 < t' < 3 GeV2, where t' = - min. The data used are collected with the HI detector at HERA in the kinematic domain 2.5 < Q(2) < 60 GeV2, 40 < W < 120 GeV No t dependence of the r(00)(04) spin density matrix element is found. A significant t dependent helicity non-conservation from the virtual photon to the rho meson is observed for the spin density matrix element combinations r(00)(5) + 2r(11)(5) and r(00)(1) + 2r(11)(1). These t dependences are consistently described by a perturbative QCD model based on the exchange of two gluons.
4.	Adloff, C, et al. (författare) Diffractive photoproduction of psi(2S) mesons at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 541:3-4, s. 251-264 Tidskriftsartikel (refereegranskat)abstract Results on diffractive photoproduction of psi(2S) mesons are presented using data collected between 1996 and 2000 with the H1 detector at the HERA ep collider. The data correspond to an integrated luminosity of 77 pb(-1). The energy dependence of the diffractive psi(2S) cross section is found to be similar to or possibly somewhat steeper than that for J/psi mesons. The dependences of the elastic and proton dissociative psi(2S) photoproduction cross sections on the squared momentum transfer t at the proton vertex are measured. The t-dependence of the elastic channel, parametrised as e(bt), yields b(el)(psi(2S)) = (4.31 +/- 0.57 +/- 0.46) GeV-2, compatible with that of the J/psi. For the proton dissociative channel the result b(pd)(psi(2S)) = (0.59 +/- 0.13 +/- 0.12) GeV-2 is 2.3 standard deviations smaller than that measured for the J/psi. With proper account of the individual wavefunctions theoretical predictions based on perturbative QCD are found to describe the measurements well. (C) 2002 Elsevier Science B.V. All rights reserved.
5.	Adloff, C, et al. (författare) Energy flow and rapidity gaps between jets in photoproduction at HERA 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 24:4, s. 517-527 Tidskriftsartikel (refereegranskat)abstract Dijet events in photon-proton collisions in which there is a large pseudorapidity separation, Deltaeta > 2.5 between the two highest E-T jets are studied with the H1 detector at HERA. The inclusive dijet cross sections are measured as functions of the longitudinal momentum fractions of the proton and photon which participate in the production of the jets, x(p)(jets) and x(gamma)(jets) respectively, Deltaeta, the pseudorapidity P separation between the two highest E-T jets, and E-T(gap), the total summed transverse energy between the jets. Rapidity gap events are defined as events in which E-T(gap) is less than E-T(cut), for E-T(cut) varied between jets 0.5 and 2.0 GeV. The fraction of dijet events with a rapidity gap is measured differentially in Deltaeta, x(p)(jets) and x(gamma)(jets). An excess of events with rapidity gaps at low values of E-T(cut) is observed above the expectation from standard photoproduction processes. This excess can be explained by the exchange of a strongly interacting colour singlet object between the jets.
6.	Adloff, C, et al. (författare) Inelastic leptoproduction of J/psi mesons at HERA 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:1, s. 41-53 Tidskriftsartikel (refereegranskat)abstract The leptoproduction of J/psi mesons is studied in inelastic reactions for four momentorri transfers 2 < Q(2) < 100GeV(2). The data were taken with the H1 detector at the electron proton collider HERA and correspond to an integrated luminosity of 77 pb(-1). Single differential and double differential cross sections are measured with increased precision compared with previous analyses. New leading order calculations within the non-relativistic QCD factorisation approach including colour octet and colour singlet contributions are compared with the data and are found to give a reasonable description of most distributions. An exception is the shape of the distribution in the J/psi fractional energy. z, which deviates significantly from that of the data. Comparisons with photoproduction are made and the polarisation of the produced J/psi meson is analysed.
7.	Adloff, C, et al. (författare) Inelastic photoproduction of J/psi mesons at HERA 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:1, s. 25-39 Tidskriftsartikel (refereegranskat)abstract An analysis of inelastic photoproduction of J/psi mesons is presented using data collected at the ep collider HERA corresponding to an integrated luminosity of above 80 pb(-1), Differential and double I < P-t/psi(2) < differential cross sections are measured in a wide kinematic region: 60 < W-gammap < 260 GeV, 1 p(t,psi)(2) < 60 GeV2 and 0.05 < z < 0.9. where z is the fraction of the energy of the exchanged photon transferred to the J/psi meson in the rest frame of the target proton. Cross sections at z less than or similar to 0.3 are presented for the first time. Theoretical calculations within the Colour Singlet Model at NLO for direct photon processes are shown to give a good description of the data in the medium z region (0.3 < z < 0.9) up to the highest p(t,psi)(2) values. A calculation using a k(t) factorisation approach in LO in the Colour Singlet Model is also able to describe these data. The data in the full z range are also compared to LO calculations within a non-relativistic QCD framework including colour octet and colour singlet contributions for direct and resolved photons. It seems possible to reconcile data and theory with modest contributions from colour octet processes. The polarisation of the J/psi meson is measured as a function of z and p(t,psi) and is reasonably described by the theoretical predictions.
8.	Adloff, C, et al. (författare) Measurement of D(+/-) meson production and F-2(c) in deep-inelastic scattering at HERA 2002 Ingår i:* Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 528:3-4, s. 199-214 Tidskriftsartikel (refereegranskat)abstract The inclusive production of D+/-(2010) mesons in deep-inelastic scattering is studied with the HI detector at HERA. In the kinematic region 1 < Q(2) < 100 GeV2 and 0.05 < y < 0.7 an e(+) p cross section for inclusive D+/- meson production of 8.50 +/- 0.42(stat.)(-100)(+1.21)(syst.) nb is measured in the visible range p(tD) > 1.5 GeV and eta(D) < 1.5. Single and double differential inclusive D*+/- meson cross sections are compared to perturbative QCD calculations in two different evolution schemes, The charm contribution to the proton structure, F-c(2)(x, Q(2)), is determined by extrapolating the visible charm cross section to the full phase space. This contribution is found to rise from about 10% at Q(2) = 1.5 GeV2 to more than 25% at Q(2) = 60 GeV2 corresponding to x values ranging from 5 x 10(-5) to 3 x 10(-3). (C) 2002 Elsevier Science B.V. All rights reserved.
9.	Adloff, C, et al. (författare) Measurement of dijet cross sections in photoproduction at HERA 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:1, s. 13-23 Tidskriftsartikel (refereegranskat)abstract Dijet cross sections as functions of several jet observables are measured in photoproduction using the HI detector at HERA. The data sample comprises e(+)p data with an integrated luminosity of 319 pb(-1). Jets are selected using the inclusive k(perpendicular to) algorithm with a minimum transverse energy of 25 GeV for the leading jet. The phase space covers longitudinal proton momentum fraction x(p) and photon longitudinal momentum fraction x(gamma) in the ranges 0.05 < x(p) < 0.6 and 0.1 < x(gamma) < 1. The predict ions of next-to-leading order perturbative QCD, including recent photon and proton parton densities, are found to be compatible with the data in a wide kinematical range.
10.	Adloff, C, et al. (författare) Measurement of dijet electroproduction at small jet separation 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 24:1, s. 33-41 Tidskriftsartikel (refereegranskat)abstract Deep-inelastic scattering data in the range 150 < Q(2) < 35000 GeV2 are used to investigate the minimum jet separation necessary to allow accurate description of the rate of dijet production using next-to-leading order perturbative QCD calculations. The required jet separation is found to be small, allowing about 1/3 of DIS data to be classified as dijet, as opposed to approximately 1/10 with more typical jet analyses. A number of precision measurements made using this dijet sample are well described by the calculations. The data are also described by the combination of leading order matrix elements and parton showers, as implemented in the QCD based Monte Carlo model RAPGAP.
11.	Adloff, C, et al. (författare) Search for excited neutrinos at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 525:1-2, s. 9-16 Tidskriftsartikel (refereegranskat)abstract We present a search for excited neutrinos using e(-) p data taken by the H1 experiment at HERA at a center-of-mass energy of 318 GeV with an integrated luminosity of 15 pb(-1). No evidence for excited neutrino production is found. Mass dependent exclusion limits are determined for the ratio of the coupling to the compositeness scale, f/Lambda, independently of the relative couplings to the SU(2) and U(1) gauge bosons. These limits extend the excluded region to higher masses than has been possible in previous searches at other colliders.
12.	Adloff, C, et al. (författare) Search for odderon-induced contributions to exclusive pi(0) photoproduction at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 544:1-2, s. 35-43 Tidskriftsartikel (refereegranskat)abstract A search for contributions to the reaction ep --> epi(0)N* from photon-odderon fusion in the photoproduction regime at HERA is reported, at an average photon-proton centre-of-mass energy = 215 GeV. The measurement proceeds via detection of the pi(0) decay photons, a leading neutron from the N* decay, and the scattered electron. No pi(0) signal is observed and an upper limit on the cross section for the photon-odderon fusion process of sigma(gammap --> pi(0)N*) < 49 nb at the 95% confidence level is derived, integrated over the experimentally accessible range of the squared four-momentum transfer at the nucleon vertex 0.02 < < 0.3 GeV2. This excludes a recent prediction from a calculation based on a non-perturbative QCD model of a photon-odderon fusion cross section above 200 nb. (C) 2002 Elsevier Science B.V. All rights reserved.
13.	Adcox, K, et al. (författare) Flow Measurements via Two-Particle Azimuthal Correlations in Au+Au Collisions at sqrt[sNN]=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89 Tidskriftsartikel (refereegranskat)abstract Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt[sNN]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone ε, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low pT. A breakdown of this ε scaling is observed for charged hadrons with pT >1.0 GeV/c.
14.	Adler, SS, et al. (författare) PHENIX on-line systems 2003 Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 560-592 Tidskriftsartikel (refereegranskat)abstract The PHENIX On-Line system takes signals from the Front End Modules (FEM) on each detector subsystem for the purpose of generating events for physics analysis. Processing of event data begins when the Data Collection Modules (DCM) receive data via fiber-optic links from the FEMs. The DCMs format and zero suppress the data and generate data packets. These packets go to the Event Builders (EvB) that assemble the events in final form. The Level-1 trigger (LVL1) generates a decision for each beam crossing and eliminates uninteresting events. The FEMs carry out all detector processing of the data so that it is delivered to the DCMs using a standard format. The FEMs also provide buffering for LVL1 trigger processing and DCM data collection. This is carried out using an architecture that is pipelined and deadtimeless. All of this is controlled by the Master Timing System (MTS) that distributes the RHIC clocks. A Level-2 trigger (LVL2) gives additional discrimination. A description of the components and operation of the PHENIX On-Line system is given and the solution to a number of electronic infrastructure problems are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
15.	Adloff, C, et al. (författare) Search for excited electrons at HERA 2002 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 548:1-2, s. 35-44 Tidskriftsartikel (refereegranskat)abstract A search for excited electron (e) production is described in which the electroweak decays e --> egamma, e* --> eZ and e* ---> nuW are considered. The data used correspond to an integrated luminosity of 120 pb(-1) taken in e(+/-)p collisions from 1994 to 2000 with the H1 detector at HERA at centre-of-mass energies of 300 and 318 GeV. No evidence for a signal is found. Mass dependent exclusion limits are derived for the ratio of the couplings to the compositeness scale, f/A. These limits extend the excluded region to higher masses than has been possible in previous direct searches for excited electrons. (C) 2002 Published by Elsevier Science B.V.
16.	Adloff, C, et al. (författare) Search for new physics in e +/- q contact interactions at HERA 2003 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 568:1-2, s. 35-47 Tidskriftsartikel (refereegranskat)abstract Deep-inelastic e(+/-) p scattering at high squared momentum transfer Q(2) up to 30 000 GeV2 is used to search for eq contact interactions associated to scales far beyond the HERA centre of mass energy. The neutral current cross section measurements dsigma / dQ(2), corresponding to integrated luminosities of 16.4 pb(-1) of e(-) p data and 100.8 pb(-1) of e(+) p data, are well described by the Standard Model and are analysed to set constraints on new phenomena. For conventional contact interactions lower limits are set on compositeness scales A ranging between 1.6-5.5 TeV. Couplings and masses of leptoquarks and squarks in R-parity violating supersymmetry are constrained to M / lambda > 0.3-1.4 TeV. A search for low scale quantum gravity effects in models with large extra dimensions provides limits on the effective Planck scale of MS > 0.8 TeV. A form factor analysis yields a bound on the radius of light quarks of R-q < 1.0 10(-18) m. (C) 2003 Published by Elsevier B.V.
17.	Adcox, K, et al. (författare) Centrality dependence of the high (PT) charged hadron suppression in Au+Au collisions at root s(NN)=130 GeV 2003 Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 561:1-2, s. 82-92 Tidskriftsartikel (refereegranskat)abstract PHENIX has measured the centrality dependence of charged hadron p(T) spectra from Au +An collisions at root(s)NN = 130 GeV The truncated mean p(T) decreases with centrality for p(T) > 2 GeV/c, indicating an apparent reduction of the contribution from hard scattering to high p(T) hadrdn production. For central collisions the yield at high p(T) is shown to be suppressed compared to binary nucleon-nucleon collision scaling of p + p, data. This suppression is monotonically increasing with centrality, but most of the change occurs below 30% centrality, i.e., for collisions with less than similar to140 participating nucleons. The observed p(T) and centrality dependence is consistent with the particle production predicted by models including hard scattering and subsequent energy loss of the scattered partons in the dense matter created in the collisions. (C) 2003 Published by Elsevier Science B.V.
18.	Adcox, K, et al. (författare) Event-by-event fluctuations in mean p(T) and mean E(T) in root s(NN)=130 GeVAu+Au collisions 2002 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 66:2 Tidskriftsartikel (refereegranskat)abstract Distributions of event-by-event fluctuations of the mean transverse momentum and mean transverse energy near mid-rapidity have been measured in Au+Au collisions at roots(NN)=130 GeV at the Relativistic Heavy-Ion Collider. By comparing the distributions to what is expected for statistically independent particle emission, the magnitude of nonstatistical fluctuations in mean transverse momentum is determined to be consistent with zero. Also, no significant nonrandom fluctuations in mean transverse energy are observed. By constructing a fluctuation model with two event classes that preserve the mean and variance of the semi-inclusive p(T) or e(T) spectra, we exclude a region of fluctuations in roots(NN)=130 GeV Au+Au collisions.
19.	Adcox, K, et al. (författare) Measurement of Lambda and (Lambda)over-bar particles in Au plus Au collisions at root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89:9 Tidskriftsartikel (refereegranskat)abstract We present results on the measurement of Lambda and (&ULambda;) over bar production in Au+Au collisions at roots(NN)=130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The (&ULambda;) over bar/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.
20.	Adcox, K, et al. (författare) Measurement of single electrons and implications for charm production in Au+Au collisions at root(NN)-N-S=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:19 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra of electrons from Au+Au collisions at roots(NN) = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025 +/- 0.004(stat) +/- 0.010( syst) in central collisions, and the corresponding charm cross section is 380 +/- 60(stat) +/- 200(syst ) mub per binary nucleon-nucleon collision.
21.	Adcox, K, et al. (författare) Net charge fluctuations in Au+Au interactions root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 89 Tidskriftsartikel (refereegranskat)abstract Data from Au+ Au interactions at s(NN)=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.
22.	Adcox, K, et al. (författare) Suppression of hadrons with large transverse momentum in central Au+Au collisions at root s(NN)=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:2 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 Gev/c < P-T < 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au + Au collisions at rootS(NN) = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p + p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p + p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.
23.	Adcox, K, et al. (författare) Transverse-mass dependence of two-pion correlations in Au+Au collisions at root(NN)-N-S=130 GeV 2002 Ingår i: Physical Review Letters. - 1079-7114. ; 88:19 Tidskriftsartikel (refereegranskat)abstract Two-pion correlations in roots(NN) = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at roots(NN) = 4.1 , 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R-out/R-side) is consistent with unity and independent of k(T) .
24.	Adler, SS, et al. (författare) Bose-Einstein correlations of charged pion pairs in Au+Au collisions at root(NN)-N-s = 200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 93:15 Tidskriftsartikel (refereegranskat)abstract Bose-Einstein correlations of identically charged pion pairs were measured by the PHENIX experiment at midrapidity in Au+Au collisions at roots(NN)=200 GeV. The Bertsch-Pratt radius parameters were determined as a function of the transverse momentum of the pair and as a function of the centrality of the collision. Using the standard core-halo partial Coulomb fits, and a new parametrization which constrains the Coulomb fraction as determined from the unlike-sign pion correlation, the ratio R-out/R-side is within 0.8-1.1 for 0.25<<1.2 GeV/c. The centrality dependence of all radii is well described by a linear scaling in N-part(1/3), and R-out/R-side for similar to0.45 GeV/c is approximately constant at unity as a function of centrality.
25.	Adler, SS, et al. (författare) Elliptic flow of identified hadrons in Au+Au collisions at root s(NN)=200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:18: 182301 Tidskriftsartikel (refereegranskat)abstract The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta<0.35) with respect to the reaction plane defined at high rapidities (eta=3-4 ). We observe that the v(2) of mesons falls below that of (anti)baryons for p(T)>2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.
26.	Adler, SS, et al. (författare) J/psi production from proton-proton collisions at root s=200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 92:5 Tidskriftsartikel (refereegranskat)abstract J/psi production has been measured in proton-proton collisions at roots=200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at the Relativistic Heavy Ion Collider. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 4.0+/-0.6(stat)+/-0.6(syst)+/-0.4(abs) mub. The mean transverse momentum is 1.80+/-0.23(stat)+/-0.16(syst) GeV/c.
27.	Adler, SS, et al. (författare) J/psi production in Au-Au collisions at root s(NN)=200 GeV 2004 Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 69:1 Tidskriftsartikel (refereegranskat)abstract First results on charm quarkonia production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The yield of J/psi's measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au-Au reactions at roots(NN) = 200 GeV is analyzed as a function of collision centrality. For this analysis we have studied 49.3x10(6) minimum bias Au-Au reactions. We present the J/psi invariant yield dN/dy for peripheral and midcentral reactions. For the most central collisions where we observe no signal above background, we quote 90% confidence level upper limits. We compare these results with our J/psi measurement from proton-proton reactions at the same energy. We find that our measurements are not consistent with models that predict strong enhancement relative to binary collision scaling.
28.	Adler, SS, et al. (författare) Midrapidity neutral-pion production in proton-proton collisions at root s 200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:24: 241803 Tidskriftsartikel (refereegranskat)abstract The invariant differential cross section for inclusive neutral-pion production in p+p collisions at roots=200 GeV has been measured at midrapidity (eta<0.35) over the range 1
29.	Adler, SS, et al. (författare) Scaling properties of proton and antiproton production in root s(NN)=200 GeV Au+Au collisions 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:17: 172301 Tidskriftsartikel (refereegranskat)abstract We report on the yield of protons and antiprotons, as a function of centrality and transverse momentum, in Au+Au collisions at rootS(NN)=200 GeV measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. In central collisions at intermediate transverse momenta (1.5
30.	Adler, SS, et al. (författare) Suppressed pi(0) production at large transverse momentum in central Au plus Au collisions at root s(NN)=200 GeV 2003 Ingår i: Physical Review Letters. - 1079-7114. ; 91:7: 072301 Tidskriftsartikel (refereegranskat)abstract Transverse momentum spectra of neutral pions in the range 1
31.	Adloff, C, et al. (författare) Search for QCD instanton-induced processes in deep-inelastic scattering at HERA 2002 Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:4, s. 495-509 Tidskriftsartikel (refereegranskat)abstract Signals of QCD instanton-induced processes are searched for in deep-inelastic scattering (DIS) at the electron-proton collider HERA in a kinematic region defined by the Bjorken-scaling variables x > 10(-3), 0.1 < y < 0.6 and photon virtualities 10 less than or similar to Q(2) < 100 GeV2. Several observables characterising hadronic final state properties of QCD instanton-induced events are exploited to identify a potentially instanton-enriched domain. While an excess of events with instanton-like topology is observed it cannot be claimed significant given the uncertainty of the standard DIS background simulation. Upper limits on the cross-section for instanton-induced processes of between 60 pb and 1000 pb are set dependent on the kinematic domain considered. The data do not exclude the cross-section predicted by instanton perturbation theory for small instanton sizes. At large instanton sizes a naive extrapolation of instanton perturbation theory yields a cross-section in the range of sensitivity of this study. Such a cross-section is not observed, in agreement with non-perturbative lattice simulations of the QCD vacuum.
32.	Adler, SS, et al. (författare) Double helicity asymmetry in inclusive midrapidity pi(0) production for polarized p+p collisions at root s=200 GeV 2004 Ingår i: Physical Review Letters. - 1079-7114. ; 93:20: 202002 Tidskriftsartikel (refereegranskat)abstract We present a measurement of the double longitudinal spin asymmetry in inclusive pi(0) production in polarized proton-proton collisions at roots=200 GeV. The data were taken at the Relativistic Heavy Ion Collider with average beam polarizations of 0.27. The measurements are the first in a program to study the longitudinal spin structure of the proton, using strongly interacting probes, at collider energies. The asymmetry is presented for transverse momenta 1-5 GeV/c at midrapidity, where next-to-leading-order perturbative quantum chromodynamic (NLO pQCD) calculations well describe the unpolarized cross section. The observed asymmetry is small and is compared to a NLO pQCD calculation with a range of polarized gluon distributions.
33.	Beral, V, et al. (författare) Alcohol, tobacco and breast cancer - collaborative reanalysis of individual data from 53 epidemiological studies, including 58515 women with breast cancer and 95067 women without the disease 2002 Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 1532-1827 .- 0007-0920. ; 87, s. 1234-45 Tidskriftsartikel (refereegranskat)abstract Alcohol and tobacco consumption are closely correlated and published results on their association with breast cancer have not always allowed adequately for confounding between these exposures. Over 80% of the relevant information worldwide on alcohol and tobacco consumption and breast cancer were collated, checked and analysed centrally. Analyses included 58515 women with invasive breast cancer and 95067 controls from 53 studies. Relative risks of breast cancer were estimated, after stratifying by study, age, parity and, where appropriate, women's age when their first child was born and consumption of alcohol and tobacco. The average consumption of alcohol reported by controls from developed countries was 6.0 g per day, i.e. about half a unit/drink of alcohol per day, and was greater in ever-smokers than never-smokers, (8.4 g per day and 5.0 g per day, respectively). Compared with women who reported drinking no alcohol, the relative risk of breast cancer was 1.32 (1.19 - 1.45, P < 0.00001) for an intake of 35 - 44 g per day alcohol, and 1.46 (1.33 - 1.61, P < 0.00001) for greater than or equal to 45 g per day alcohol. The relative risk of breast cancer increased by 7.1% (95% CI 5.5-8.7%; P<0.00001) for each additional 10 g per day intake of alcohol, i.e. for each extra unit or drink of alcohol consumed on a daily basis. This increase was the same in ever-smokers and never-smokers (7.1 % per 10 g per day, P < 0.00001, in each group). By contrast, the relationship between smoking and breast cancer was substantially confounded by the effect of alcohol. When analyses were restricted to 22 255 women with breast cancer and 40 832 controls who reported drinking no alcohol, smoking was not associated with breast cancer (compared to never-smokers, relative risk for ever-smokers= 1.03, 95% CI 0.98 - 1.07, and for current smokers=0.99, 0.92 - 1.05). The results for alcohol and for tobacco did not vary substantially across studies, study designs, or according to 15 personal characteristics of the women; nor were the findings materially confounded by any of these factors. If the observed relationship for alcohol is causal, these results suggest that about 4% of the breast cancers in developed countries are attributable to alcohol. In developing countries, where alcohol consumption among controls averaged only 0.4 g per day, alcohol would have a negligible effect on the incidence of breast cancer. In conclusion, smoking has little or no independent effect on the risk of developing breast cancer; the effect of alcohol on breast cancer needs to be interpreted in the context of its beneficial effects, in moderation, on cardiovascular disease and its harmful effects on cirrhosis and cancers of the mouth, larynx, oesophagus and liver. (C) 2002 Cancer Research UK.
34.	Carolipio, E. M., et al. (författare) The toroidicity-induced Alfven eigenmode structure in DIII-D : Implications of soft x-ray and beam-ion loss data 2001 Ingår i: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 8:7, s. 3391-3401 Tidskriftsartikel (refereegranskat)abstract The internal structure of the toroidicity-induced Alfven eigenmode (TAE) is studied by comparing soft x-ray profile and beam ion loss data taken during TAE activity in the DIII-D tokamak [W. W. Heidbrink , Nucl. Fusion 37, 1411 (1997)] with predictions from theories based on ideal magnetohydrodynamic (MHD), gyrofluid, and gyrokinetic models. The soft x-ray measurements indicate a centrally peaked eigenfunction, a feature which is closest to the gyrokinetic model's prediction. The beam ion losses are simulated using a guiding center code. In the simulations, the TAE eigenfunction calculated using the ideal MHD model acts as a perturbation to the equilibrium field. The predicted beam ion losses are an order of magnitude less than the observed similar to6%-8% losses at the peak experimental amplitude of deltaB(r)/B(0)similar or equal to2-5x10(-4).
35.	Bennet, W, et al. (författare) Complement regulatory proteins on human and porcine nontransgenic and hDAF transgenic islet cells: expression and role in susceptibility to lysis by human serum 2000 Ingår i: Transplantation proceedings. - 0041-1345. ; 32 Tidskriftsartikel (refereegranskat)
36.	Bennet, W, et al. (författare) Damage to porcine islets of Langerhans after exposure to human blood in vitro, or after intraportal transplantation to cynomologus monkeys: protective effects of sCR1 and heparin 2000 Ingår i: Transplantation. - : Ovid Technologies (Wolters Kluwer Health). - 0041-1337. ; 69:5, s. 711-719 Tidskriftsartikel (refereegranskat)
37.	Bennet, W, et al. (författare) Damage to porcine islets of Langerhans after exposure to human blood invitro, or after intraportal transplantation to cynomologus monkeys:protective effects of sCR1 and heparin [see comments] 2000 Ingår i: Transplantation. ; 69, s. 711- Tidskriftsartikel (refereegranskat)
38.	Bennet, W, et al. (författare) Expression of complement regulatory proteins on islets of Langerhans: a comparison between human islets and islets isolated from normal and hDAF transgenic pigs 2001 Ingår i: Transplantation. - : Ovid Technologies (Wolters Kluwer Health). - 0041-1337. ; 27, s. 312- Tidskriftsartikel (refereegranskat)
39.	Bennet, W, et al. (författare) Porcine islets of langerhans isolated from normal and hDAF transgenic pigs elicit the same acute inflammatory reaction during exposure to human blood; inhibition of the response with soluble complement receptor 1 and heparin 2000 Ingår i: Transplantation proceedings. - : Elsevier BV. - 0041-1345. ; 32:5, s. 1065-1065 Tidskriftsartikel (refereegranskat)
40.	Bennet, W, et al. (författare) Porcine islets of langerhans isolated from normal and hDAF transgenic pigselicit the same acute inflammatory reaction during exposure to humanblood; inhibition of the response with soluble complement 2000 Ingår i: Transplant Proc. ; 32 Tidskriftsartikel (refereegranskat)
41.	Challis, B G, et al. (författare) Mice lacking pro-opiomelanocortin are sensitive to high-fat feeding but respond normally to the acute anorectic effects of peptide-YY(3-36). 2004 Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 101:13, s. 4695-700 Tidskriftsartikel (refereegranskat)abstract Inactivating mutations of the pro-opiomelanocortin (POMC) gene in both mice and humans leads to hyperphagia and obesity. To further examine the mechanisms whereby POMC-deficiency leads to disordered energy homeostasis, we have generated mice lacking all POMC-derived peptides. Consistent with a previously reported model, Pomc(-/-) mice were obese and hyperphagic. They also showed reduced resting oxygen consumption associated with lowered serum levels of thyroxine. Hypothalami from Pomc(-/-) mice showed markedly increased expression of melanin-concentrating hormone mRNA in the lateral hypothalamus, but expression of neuropeptide Y mRNA in the arcuate nucleus was not altered. Provision of a 45% fat diet increased energy intake and body weight in both Pomc(-/-) and Pomc(+/-) mice. The effects of leptin on food intake and body weight were blunted in obese Pomc(-/-) mice whereas nonobese Pomc(-/-) mice were sensitive to leptin. Surprisingly, we found that Pomc(-/-) mice maintained their acute anorectic response to peptide-YY(3-36) (PYY(3-36)). However, 7 days of PYY(3-36) administration had no effect on cumulative food intake or body weight in wild-type or Pomc(-/-) mice. Thus, POMC peptides seem to be necessary for the normal response of energy balance to high-fat feeding, but not for the acute anorectic effect of PYY(3-36) or full effects of leptin on feeding. The finding that the loss of only one copy of the Pomc gene is sufficient to render mice susceptible to the effects of high fat feeding emphasizes the potential importance of this locus as a site for gene-environment interactions predisposing to obesity.
42.	Cramer, W, et al. (författare) Global response of terrestrial ecosystem structure and function to CO2 and climate change: results from six dynamic global vegetation models 2001 Ingår i: Global Change Biology. - : Wiley. - 1354-1013. ; 7, s. 357-373 Tidskriftsartikel (refereegranskat)
43.	Hammarström, Per, 1972-, et al. (författare) D18G Transthyretin is Monomeric, Aggregation Prone, and Non-Detectable in Plasma and Cerbrospinal Fluid - A Prescription for CNS Amyloidosis? 2003 Ingår i: Biochemistry. - 0006-2960 .- 1520-4995. ; 42, s. 6656-6663 Tidskriftsartikel (refereegranskat)
44.	Hammarström, Per, et al. (författare) D18G transthyretin is monomeric, aggregation prone, and not detectable in plasma and cerebrospinal fluid : A prescription for central nervous system amyloidosis? 2003 Ingår i: Biochemistry. - : American Chemical Society (ACS). - 0006-2960 .- 1520-4995. ; 42:22, s. 6656-6663 Tidskriftsartikel (refereegranskat)abstract Over 70 transthyretin (TTR) mutations facilitate amyloidosis in tissues other than the central nervous system (CNS). In contrast, the D18G TTR mutation in individuals of Hungarian descent leads to CNS amyloidosis. D18G forms inclusion bodies in Escherichia coli, unlike the other disease-associated TTR variants overexpressed to date. Denaturation and reconstitution of D18G from inclusion bodies afford a folded monomer that is destabilized by 3.1 kcal/mol relative to an engineered monomeric version of WT TTR. Since TTR tetramer dissociation is typically rate limiting for amyloid formation, the monomeric nature of D18G renders its amyloid formation rate 1000-fold faster than WT. It is perplexing that D18G does not lead to severe early onset systemic amyloidosis, given that it is the most destabilized TTR variant characterized to date, more so than variants exhibiting onset in the second decade. Instead, CNS impairment is observed in the fifth decade as the sole pathological manifestation, however, benign systemic deposition is also observed. Analysis of heterozygote D18G patient's serum and cerebrospinal fluid (CSF) detects only WT TTR, indicating that D18G is either rapidly degraded postsecretion or degraded within the cell prior to secretion, consistent with its inability to form hybrid tetramers with WT TTR. The nondetectable levels of D18G TTR in human plasma explain the absence of an early onset systemic disease. CNS disease may result owing to the sensitivity of the CNS to lower levels of D18G aggregate. Alternatively, or in addition, we speculate that a fraction of D18G made by the choroid plexus can be transiently tetramerized by the locally high thyroxine (T4) concentration, chaperoning it out into the CSF where it undergoes dissociation and amyloidogenesis due to the low T4 CSF concentration. Selected small molecule tetramer stabilizers can transform D18G from a monomeric aggregation-prone state to a nonamyloidogenic tetramer, which may prove to be a useful therapeutic strategy against TTR-associated CNS amyloidosis.
45.	Lundgren, T, et al. (författare) Soluble complement receptor 1 (TP10) preserves adult porcine islet morphology after intraportal transplantation into cynomolgus monkeys 2001 Ingår i: Transplantation proceedings. - : Elsevier BV. - 0041-1345. ; 33, s. 725- Tidskriftsartikel (refereegranskat)
46.	Lundgren, T, et al. (författare) Soluble complement receptor 1(TP10) preserves adult porcine islets morphology after intraportal transplantation into cynomolgus monkeys. 2000 Ingår i: TRANSPLANTATION. - 0041-1337. ; 69:8, s. S420-S420 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
47.	Mitchell, JT, et al. (författare) Event reconstruction in the PHENIX central arm spectrometers 2002 Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 482:1-2, s. 491-512 Tidskriftsartikel (refereegranskat)abstract The central arm spectrometers for the PHENIX experiment at the Relativistic Heavy Ion Collider have been designed for the optimization of particle identification in relativistic heavy ion collisions. The spectrometers present a challenging environment for event reconstruction due to a very high track multiplicity in a complicated, focusing, magnetic field. In order to meet this challenge, nine distinct detector types are integrated for charged particle tracking, momentum reconstruction. and particle identification. The techniques which have been developed for the task of event reconstruction are described.

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