7,249 research outputs found

    Chern-Simons Invariants of Closed Hyperbolic 3-Manifolds

    Get PDF
    The Chern-Simons invariants of irreducible U(n)- flat connections on compact hyperbolic 3-manifolds of the form {\Gamma}\H^3 are derived. The explicit formula for the Chern-Simons functional is given in terms of Selberg type zeta functions related to the twisted eta invariants of Atiyah-Patodi-Singer.Comment: 10 pages, 2 diagram

    On the rapidity dependence of the average transverse momentum in hadronic collisions

    Full text link
    The energy and rapidity dependence of the average transverse momentum ⟨pT⟩\langle p_T \rangle in pppp and pApA collisions at RHIC and LHC energies are estimated using the Colour Glass Condensate (CGC) formalism. We update previous predictions for the pTp_T - spectra using the hybrid formalism of the CGC approach and two phenomenological models for the dipole - target scattering amplitude. We demonstrate that these models are able to describe the RHIC and LHC data for the hadron production in pppp, dAudAu and pPbpPb collisions at pT≤20p_T \le 20 GeV. Moreover, we present our predictions for ⟨pT⟩\langle p_T \rangle and demonstrate that the ratio ⟨pT(y)⟩/⟨pT(y=0)⟩\langle p_{T}(y)\rangle / \langle p_{T}(y = 0)\rangle decreases with the rapidity and has a behaviour similar to that predicted by hydrodynamical calculations.Comment: 11 pages, 7 figures; revised version: new results for the average transverse momentum at partonic level added in fig. 4; Results and Discussion section has been improved and enlarge

    Testing the running coupling kTk_{T}-factorization formula for the inclusive gluon production

    Full text link
    The inclusive gluon production at midrapidities is described in the Color Glass Condensate formalism using the kTk_T - factorization formula, which was derived at fixed coupling constant considering the scattering of a dilute system of partons with a dense one. Recent analysis demonstrated that this approach provides a satisfactory description of the experimental data for the inclusive hadron production in pp/pA/AApp/pA/AA collisions. However, these studies are based on the fixed coupling kTk_T - factorization formula, which does not take into account the running coupling corrections, which are important to set the scales present in the cross section. In this paper we consider the running coupling corrected kTk_T - factorization formula conjectured some years ago and investigate the impact of the running coupling corrections on the observables. In particular, the pseudorapidity distributions and charged hadrons multiplicity are calculated considering pppp, dAu/pPbdAu/pPb and AuAu/PbPbAuAu/PbPb collisions at RHIC and LHC energies. We compare the corrected running coupling predictions with those obtained using the original kTk_T - factorization assuming a fixed coupling or a prescription for the inclusion of the running of the coupling. Considering the Kharzeev - Levin - Nardi unintegrated gluon distribution and a simplified model for the nuclear geometry, we demonstrate that the distinct predictions are similar for the pseudorapidity distributions in pp/pA/AApp/pA/AA collisions and for the charged hadrons multiplicity in pp/pApp/pA collisions. On the other hand, the running coupling corrected kTk_T - factorization formula predicts a smoother energy dependence for dN/dηdN/d\eta in AAAA collisions.Comment: 9 pages and 4 figure

    Production of exotic charmonium in γγ\gamma \gamma interactions at hadronic colliders

    Get PDF
    In this paper we investigate the Exotic Charmonium (EC) production in γγ\gamma \gamma interactions present in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC) energies as well as for the proposed energies of the Future Circular Collider (FCC). Our results demonstrate that the experimental study of these processes is feasible and can be used to constrain the theoretical decay widths and shed some light on the configuration of the considered multiquark states.Comment: 7 pages, 2 figures, 3 tables. v2: Revised version published in Physical Review

    Knowledge management in projects

    Get PDF
    Knowledge Transfer in Project-based Organizations has been recognized as productivity and economic growth promoters that are currently not properly managed. Therefore, it is critical to investigate the importance of knowledge regarding its acquisition, use and transfer across all departments of an organization. The main objective of this work was to evaluate how modern organizations from different business sectors manage and share their knowledge by following the Knowledge Management and Transfer Life-Cycles when developing their projects. Organizational surveys were performed to employees working in project management within Portuguese organizations (or with representation in Portugal,) from multiple business sectors and holding different hierarchical positions. The present study revealed that most Companies can identify, capture and retain the relevant knowledge, and apply it to the development of other projects. However, the steps corresponding to the transfer of knowledge between collaborators within the organization and to the evaluation/review of the benefit generated by the transferred knowledge are not being followed. The inexistence of a Project department or a team dedicated to projects within the organization seems to be limiting the effectiveness of knowledge management and transfer.info:eu-repo/semantics/acceptedVersio

    About possible contribution of intrinsic charm component to inclusive spectra of charmed mesons

    Full text link
    We calculate differential energy spectra (xFx_F-distributions) of charmed particles produced in proton-nucleus collisions, assuming the existence of intrinsic heavy quark components in the proton wave function. For the calculation, the recently proposed factorization scheme is used, based on the Color Glass Condensate theory and specially suited for predictions of a production of particles with large rapidities. It is argued that the intrinsic charm component can, if it exists, dominate in a sum of two components, intrinsic + extrinsic, of the inclusive spectrum of charmed particles produced in proton-nucleus collisions at high energies, in the region of medium xFx_F, 0.15<xF<0.70.15 < x_F < 0.7, and can give noticeable contribution to atmospheric fluxes of prompt muons and neutrinos.Comment: 10 pages, 4 figures. Version published in J. Phys. G
    • …
    corecore