10,105 research outputs found

    Geoneutrinos in Borexino

    Full text link
    This paper describes the Borexino detector and the high-radiopurity studies and tests that are integral part of the Borexino technology and development. The application of Borexino to the detection and studies of geoneutrinos is discussed.Comment: Conference: Neutrino Geophysics Honolulu, Hawaii December 14-16, 200

    Elliptic Flow, Initial Eccentricity and Elliptic Flow fluctuations in Heavy Ion Collisions at RHIC

    Get PDF
    We present measurements of elliptic flow and event-by-event fluctuations established by the PHOBOS experiment. Elliptic flow scaled by participant eccentricity is found to be similar for both systems when collisions with the same number of participants or the same particle area density are compared. The agreement of elliptic flow between Au+Au and Cu+Cu collisions provides evidence that the matter is created in the initial stage of relativistic heavy ion collisions with transverse granularity similar to that of the participant nucleons. The event-by-event fluctuation results reveal that the initial collision geometry is translated into the final state azimuthal particle distribution, leading to an event-by-event proportionality between the observed elliptic flow and initial eccentricity.Comment: To appear in the proceedings of the Lake Louise Winter Institute 2007. The proceedings of the institute will be published by World Scientifi

    Beam-Energy and System-Size Dependence of Dynamical Net Charge Fluctuations

    Full text link
    We present measurements of net charge fluctuations in Au+AuAu + Au collisions at sNN=\sqrt{s_{NN}} = 19.6, 62.4, 130, and 200 GeV, Cu+CuCu + Cu collisions at sNN=\sqrt{s_{NN}} = 62.4, 200 GeV, and p+pp + p collisions at s=\sqrt{s} = 200 GeV using the net charge dynamical fluctuations measure ν+−,dyn\nu_{+-,dyn}. The dynamical fluctuations are non-zero at all energies and exhibit a rather modest dependence on beam energy. We find that at a given energy and collision system, net charge dynamical fluctuations violate 1/Nch1/N_{ch} scaling, but display approximate 1/Npart1/N_{part} scaling. We observe strong dependence of dynamical fluctuations on the azimuthal angular range and pseudorapidity widths.Comment: 4 pages, 4 figures, presented at the 19th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions, "Quark Matter 2008", Jaipur, India, February 4-10, 200

    Caudal cervical vertebral morphological variation is not associated with clinical signs in Warmblood horses

    Get PDF
    Background Variation in equine caudal cervical spine morphology at C6 and C7 has high prevalence in Warmblood horses and is suspected to be associated with pain in a large mixed-breed group of horses. At present no data exist on the relationship between radiographic phenotype and clinical presentation in Warmblood horses in a case-control study. Objectives To establish the frequency of radiographically visible morphologic variation in a large group of Warmblood horses with clinical signs and compare this with a group without clinical signs. We hypothesised that occurrence of morphologic variation in the case group would not differ from the control group, indicating there is no association between clinical signs and morphologic variation. Study design Retrospective case-control. Methods Radiographic presence or absence of morphologic variation of cervical vertebrae C6 and C7 was recorded in case (n = 245) and control horses (n = 132). Case and control groups were compared by univariable Pearson's Chi-square and multivariable logistic regression for measurement variables age, sex, breed, degenerative joint disease and morphologic variation at C6 and C7. Odds ratio and confidence intervals were obtained. A P <= 0.05 was considered statistically significant. Results Morphologic variation at C6 and C7 (n = 108/377 = 28.6%; Cases 58/245 = 23.7%; Control 50/132 = 38%) was less frequent in horses with clinical signs in univariable testing (OR 0.48, 95% CI 0.3-0.8, P = 0.001). Age, sex, breed and degenerative joint disease were not retained in the final multivariable logistic regression step whereas morphologic variation remained significantly less present in horses with clinical signs. Main limitations Possible demographic differences between equine clinics. Conclusions Morphologic variation in the caudal cervical spine was detected more frequently in horses without clinical signs. Therefore, radiographic presence of such variation does not necessarily implicate the presence of clinical signs

    Energy and system dependence of high-pTp_T triggered two-particle near-side correlations

    Get PDF
    Previous studies have indicated that the near-side peak of high-pTp_T triggered correlations can be decomposed into two parts, the \textit{Jet} and the \textit{Ridge}. We present data on the yield per trigger of the \textit{Jet} and the \textit{Ridge} from d+Aud+Au, Cu+CuCu+Cu and Au+AuAu+Au collisions at sNN\sqrt{s_{NN}} = 62.4 GeV and 200 GeV and compare data on the \textit{Jet} to PYTHIA 8.1 simulations for p+pp+p. PYTHIA describes the \textit{Jet} component up to a scaling factor, meaning that PYTHIA can provide a better understanding of the \textit{Ridge} by giving insight into the effects of the kinematic cuts. We present collision energy and system dependence of the \textit{Ridge} yield, which should help distinguish models for the production mechanism of the \textit{Ridge}.Comment: 4 pages, 6 figures, proceedings for Hot Quarks in Estes Park, Colorad

    Pseudorapidity dependence of parton energy loss in relativistic heavy ion collisions

    Full text link
    We analyze the recent data from the BRAHMS Collaboration on the pseudorapidity dependence of nuclear modification factors in Au+Au collisions at sNN\sqrt{s_{NN}} = 200 GeV by using the full three dimensional hydrodynamic simulations for the density effects on parton energy loss. We first compute the transverse spectra at η=0\eta=0 and 2.2, and next take a ratio Rη=RAA(η=2.2)/RAA(η=0)R_{\eta}=R_{AA}(\eta=2.2)/R_{AA}(\eta=0), where RAAR_{AA} is a nuclear modification factor. It is shown that hydrodynamic components account for Rη≃1R_{\eta}\simeq 1 at low pTp_\mathrm{T} and that quenched pQCD components lead Rη<1R_{\eta} < 1 at high pTp_\mathrm{T} which are consistent with the data. Strong suppression at η=2.2\eta=2.2 is compatible with the parton energy loss in the final state.Comment: 5 pages, 4 figures; one figure adde
    • …
    corecore