7,239 research outputs found

    Reconstituting the Public-Private Divide under Global Conditions: the Case of Dutch and British Water Management

    Full text link
    How is the line to be drawn in the public–private divide when those who would bridge it also assert that globalization restricts the state's ability to deliver public policy objectives? Critics of modernity have seen the distinction between two public–private discourses, state and market, the open and the hidden, as a modern flawed version of classic notions of the democratic citizen community. The projection of the divide on to a global stage appears to take us even further from that ideal. We report the results of a narrative analysis of the way practitioners in the Netherlands and England and Wales now deliver global public goods in the management of water as compared with their predecessors delivering public health and progress in the 19th century. In their adherence to the water systems concept we find them actively supporting a transparent public sphere beyond the state where multiple forms of agency assert global responsibilities

    Probing the atmosphere of the bulge G5III star OGLE-2002-BUL-069 by analysis of microlense H alpha line

    Full text link
    We discuss high-resolution, time-resolved spectra of the caustic exit of the binary microlensing event OGLE 2002-BUL-69 obtained with UVES on the VLT. The source star is a G5III giant in the Galactic Bulge. During such events, the source star is highly magnified, and a strong differential magnification around the caustic resolves its surface. Using an appropriate model stellar atmosphere generated by the NextGEN code we obtained a model light curve for the caustic exit and compared it with a dense set of photometric observations obtained by the PLANET microlensing follow up network. We further compared predicted variations in the H alpha equivalent width with those measured from our spectra. While the model and observations agree in the gross features, there are discrepancies suggesting shortcomings in the model, particularly for the H alpha line core, where we have detected amplified emission from the stellar chromosphere as the source star's trailing limb exited the caustic. This achievement became possible by the provision of the OGLE-III Early Warning System, a network of small telescopes capable of nearly-continuous round-the-clock photometric monitoring, on-line data reduction, daily near-real-time modelling in order to predict caustic crossing parameters, and a fast and efficient response of a 8m-class telescope to a ``Target-Of-Opportunity'' observation request.Comment: 4 pages Latex, 3 figures, accepted for publication to astronomy and astrophysics letter

    Recent QCD results from the Tevatron

    Full text link
    Recent QCD related results from the CDF and the D0 experiments are presented based on proton anti-proton collision data at sqrt(s)=1.96 TeV, taken in Run II of the Fermilab Tevatron Collider. Measured observables include inclusive photon and diphoton production, vector boson plus jets production, event shape variables, and inclusive multijet production. The measurement results are compared to QCD theory calculations in different approximations. A determination of the strong coupling constant from jet data is presented.Comment: 12 pages with 14 figures, to appear in the proceedings of the "Ringberg Workshop: New Trends in HERA Physics 2011", Ringberg Castle, Germany, 25-28 September, 201

    Limb-darkening measurements for a cool red giant in microlensing event OGLE 2004-BLG-482

    Full text link
    Aims: We present a detailed analysis of OGLE 2004-BLG-482, a relatively high-magnification single-lens microlensing event which exhibits clear extended-source effects. These events are relatively rare, but they potentially contain unique information on the stellar atmosphere properties of their source star, as shown in this study. Methods: Our dense photometric coverage of the overall light curve and a proper microlensing modelling allow us to derive measurements of the OGLE 2004-BLG-482 source star's linear limb-darkening coefficients in three bands, including standard Johnson-Cousins I and R, as well as in a broad clear filter. In particular, we discuss in detail the problems of multi-band and multi-site modelling on the expected precision of our results. We also obtained high-resolution UVES spectra as part of a ToO programme at ESO VLT from which we derive the source star's precise fundamental parameters. Results: From the high-resolution UVES spectra, we find that OGLE 2004-BLG-482's source star is a red giant of MK type a bit later than M3, with Teff = 3667 +/- 150 K, log g = 2.1 +/- 1.0 and an assumed solar metallicity. This is confirmed by an OGLE calibrated colour-magnitude diagram. We then obtain from a detailed microlensing modelling of the light curve linear limb-darkening coefficients that we compare to model-atmosphere predictions available in the literature, and find a very good agreement for the I and R bands. In addition, we perform a similar analysis using an alternative description of limb darkening based on a principal component analysis of ATLAS limb-darkening profiles, and also find a very good agreement between measurements and model predictions.Comment: Accepted in A&

    Exclusive Double Diffractive Events: Menu for LHC

    Full text link
    Exclusive double diffractive events (EDDE) are considered in the framework of the Regge-eikonal approach and perturbative calculations for "hard" subprocesses. Total and differential cross-sections for processes p+pp+X+pp+p\to p+X+p are calculated.Comment: 18 pages, Latex 2.09, 6 postscript figures, references are adde

    Central Diffraction at the LHCb

    Full text link
    The LHCb experiment is shown to be ideal for studies of exclusive final states from central diffractive reactions. The gluon-rich environment of the central system allows detailed QCD studies and searches for exotic meson states, such as glueballs, molecules, hybrids and new charmonium-like states. It would also provide a good testing ground for detailed studies of heavy quarkonia. Due to its distinct design features, the LHCb can accurately measure the low-mass central systems with good purity. The efficiency of the FSC system for detecting rapidity gaps is shown to be adequate for the proposed studies. With this detector arrangement, valuable new data can be obtained by tagging central diffractive processes

    Forward Physics with Rapidity Gaps at the LHC

    Get PDF
    A rapidity gap program with great potential can be realized at the Large Hadron Collider, LHC, by adding a few simple forward shower counters (FSCs) along the beam line on both sides of the main central detectors, such as CMS. Measurements of single diffractive cross sections down to the lowest masses can be made with an efficient level-1 trigger. Exceptionally, the detectors also make feasible the study of Central Diffractive Excitation, and in particular the reaction g + g to g + g, in the color singlet channel, effectively using the LHC as a gluon-gluon collider.Comment: 15 pages, 11 figure

    Measurement of exclusive production of scalar χc0\chi_{c0} meson in proton-(anti)proton collisions via χc0π+π\chi_{c0} \to \pi^{+}\pi^{-} decay

    Full text link
    We consider a measurement of exclusive production of scalar χc(0++)\chi_{c}(0^{++}) meson in the proton-proton collisions at LHC and RHIC and in the proton-antiproton collisions at the Tevatron via χc0π+π\chi_{c0} \to \pi^{+}\pi^{-} decay. The corresponding amplitude for exclusive double-diffractive χc0\chi_{c0} meson production was obtained within the ktk_{t}-factorization approach including virtualities of active gluons and the corresponding cross section is calculated with unintegrated gluon distribution functions (UGDFs) known from the literature. The four-body ppppπ+πp p \to p p \pi^+ \pi^- reaction constitutes an irreducible background to the exclusive χc0\chi_{c0} meson production. We calculate several differential distributions for pp(pˉ)pp(pˉ)χc0pp(\bar{p}) \to pp(\bar{p})\chi_{c0} process including absorptive corrections. The influence of kinematical cuts on the signal-to-background ratio is investigated. Corresponding experimental consequences are discussed.Comment: 16 pages, 10 figures, 2 table
    corecore