29 research outputs found

    Measurement of hadronic cross section and preliminary results on the pion form factor using the radiative return at DAPHNE

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    In the fixed energy environment of the e+ee^{+}e^{-} collider DAΦ\PhiNE, KLOE can measure the cross section of the process e+ee^{+}e^{-} \to hadrons as a function of the hadronic system energy using the radiative return. At energies below 1 GeV, e+eρπ+πe^{+}e^{-} \to \rho \to \pi^{+}\pi^{-} is the dominating hadronic process. We report here on the status of the analysis for the e^{+}e^{-} \to \ppg channel, which allows to obtain a preliminary measurement of the pion form factor using an integrated luminosity of 73pb1\sim73 pb^{-1}.Comment: Invited talk at the Seventh International Workshop on Tau Lepton Physics (TAU02-WE07), Santa Cruz, Ca, USA, Sept 2002, 9 pages, LaTeX, 9 eps figure

    Measuring the hadronic cross section via radiative return

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    Recently it has been demonstrated that particle factories, such as DAPHNE and PEP-II, operating at fixed center-of-mass energies, are able to measure hadronic cross sections as a function of the hadronic system energy using the raditive return. This paper is an experimental overview of the progress in this aera. Preliminary results from KLOE for the process e+e- -> \rho \gamma -> \pi+\pi-\gamma and a fit to the pion form factor are presented. Some first results from the BABAR collaboration are also shown.Comment: Invited talk presented at RADCOR/Loops and Legs 2002, Kloster Banz/Germany, September 8-13 2002, 6 pages, 2 Figures; v1: references added, typos correcte

    Measurement of the branching fraction for the decay KS --> pi e nu

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    We present a measurement of the branching ratio BR(KS --> pi e nu) performed using the KLOE detector. KS mesons are produced in the reaction e+ e- --> phi --> KS KL at the DAFNE collider. In a sample of about 5 million KS-tagged events we find 624 +- 30 semileptonic KS decays. Normalizing to the KS --> pi+ pi- count in the same data sample, we obtain BR(KS --> pi e nu) = (6.91 +- 0.37) 10^-4, in agreement with the Standard Model expectation.Comment: 9 pages, 5 Encapsulated Postscript figures. Submitted to Phys. Lett.

    Measurement of Gamma(phi -> eta' gamma)/Gamma(phi -> eta gamma) and the pseudoscalar mixing angle

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    We have measured the radiative decays phi -> eta gamma, phi ->etaprime gamma selecting pi+ pi- gamma gamma gamma final state in a sample of about 5 times 10^7 phi mesons produced at the Frascati phi factory DAFNE. We obtain Gamma(phi -> etaprime gamma)/Gamma(phi -> eta gamma)=(4.70 +- 0.47 +- 0.31) times 10^-3. From this result we derive new accurate values for the branching ratio BR(phi ->etaprime gamma) = (6.10 +- 0.61 +- 0.43) times 10^-5, and the mixing angle of pseudoscalar mesons in the flavour basis phi_P=(41.8 +1.9 -1.6) degrees.Comment: Submitted to Phys. Lett.

    Study of the Decay phi --> eta pi0 gamma with the KLOE detector

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    In a sample of 5.3x10^7 phi-decays observed with the KLOE detector at the Frascati phi-factory Dafne we find 605 eta pi0 gamma events with eta --> gamma\gamma and 197 eta pi0 gamma events with eta --> pi+ pi- pi0. The decay phi --> eta pi0 gamma is dominated by the process phi --> a0 gamma. From a fit to the eta pi0 mass spectrum we find BR(phi --> ao(980) gamma)= (7.4 +- 0.7)x10^-5.Comment: 12 pages, 6 figures, submitted to Phys.Lett.

    Measurement of the ratio Gamma(K_L -> gamma gamma)/Gamma(K_L -> pi^0 pi^0 pi^0) with the KLOE detector

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    We have measured the ratio R=Gamma(K_L -> gamma gamma)/ \Gamma(K_L -> 3 pi^0) using the KLOE detector. From a sample of ~ 10^9 phi-mesons produced at DAFNE, the Frascati phi-factory, we select ~ 1.6 10^8 K_L-mesons tagged by observing K_S -> pi^+ pi^- following the reaction e^+ e^- -> phi -> K_L K_S. From this sample we select 27,375 K_L -> gamma gamma events and obtain R = (2.79 \pm 0.02_{stat} \pm 0.02_{syst}) \times 10^{-3}. Using the world average value for BR(K_{L} -> 3 pi^0), we obtain BR(K_{L} -> gamma gamma) = (5.89 \pm 0.07 \pm 0.08) \times 10^{-4} where the second error is due to the uncertainty on the 3 pi^0 branching fraction.Comment: 14 page

    Socio-economic analysis and stakeholders involvement: the case of the Bue Marino Caves tourist valorization

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    The authors are involved in the research project \u201cSustainable Exploitation of karst areas: study and conservation of biodiversity in the caves of Sardinia (KARSTBIOSAR)\u201d, funded by the Region of Sardinia with LR 7/2007. The aims of this paper is to show the progress of the project, focusing on the case study of the \u2018Bue Marino\u2019 Caves. The area has been chosen mainly because it is characterized by a very vulnerable natural system for its high and fragile biodiversity joined to a heavy tourist pressure. More than annual 60000 visitors coming from all over the world, are distributed in a relatively short tourist season from April to October. During the winter time, the access to the Caves is impossible for the high level of the sea-waters. The Stakeholder Analysis is an useful tool to enucleate the complicated and multi-faced relations between local communities and policy-makers, also in order to reconcile private and public goals, helping local communities to better understand their actual goals and the political institutions to identify supporters and opponents to eventual and alternative protectionist/exploiting policies. We will identify the network of interests surrounding the \u2018Bue Marino\u2019 Caves, by analyzing: (1) the social network of interests and actors; (2) the key patterns of the interaction among the actors; (3) the values, interests, aptitudes and aspirations of stakeholders; (4) the reasons for opposition/support to the management patterns of the Caves; (5) the role of the public institutions in the governance process. Following an already tested method, we discuss the availability of quantitative and qualitative data, these latter regarding the stakeholders\u2019 perceptions about the necessity of managing biodiversity of the Caves, balancing relevant socio-economic and environmental goals. We report some results about the cooperative involvement that has already been established between researches and some of the key stakeholders during several preceding meetings. The free commitment of participants during meetings and interviews shows us the possibility to further enhance the sharing of common ideas about the socio-economic convenience of improving a well defined managing policy, oriented to the reconciliation of environmental protection and tourism exploitation. The results of the field research will usefully support the development of a \u2018common pool of knowledge' that both institutions and private actors can use in identifying a model for selecting a shared environmental policy, thus having more chances of successful policy choices
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