195 research outputs found

    Neutrinos and Future Concordance Cosmologies

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    We review the free parameters in the concordance cosmology, and those which might be added to this set as the quality of astrophysical data improves. Most concordance parameters encode information about otherwise unexplored aspects of high energy physics, up to the GUT scale via the "inflationary sector," and possibly even the Planck scale in the case of dark energy. We explain how neutrino properties may be constrained by future astrophysical measurements. Conversely, future neutrino physics experiments which directly measure these parameters will remove uncertainty from fits to astrophysical data, and improve our ability to determine the global properties of our universe.Comment: Proceedings of paper given at Neutrino 2008 meeting (by RE

    Hadrons with Charm and Beauty

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    By combining potential models and QCD spectral sum rules (QSSR), we discuss the spectroscopy of the (bcˉ)(b\bar c) mesons and of the (bcq)(bcq), (ccq)(ccq) and (bbq)(bbq) baryons (q≡d{q}\equiv {d} or ss), the decay constant and the (semi)leptonic decay modes of the BcB_c meson. For the masses, the best predictions come from potential models and read: MBc=(6255±20)M_{B_c} = (6255 \pm 20)~MeV, MBc∗=(6330±20)M_{B^*_c} = (6330 \pm 20)~MeV, MΛ(bcu)=(6.93±0.05)M_{\Lambda(bcu)} = (6.93\pm 0.05)~GeV, MΩ(bcs)=(7.00±0.05)M_{\Omega(bcs)} = (7.00\pm 0.05)~GeV, MΞ∗(ccu)=(3.63±0.05)M_{\Xi^*(ccu)} =(3.63\pm 0.05)~GeV and MΞ∗(bbu)=(10.21±0.05)M_{\Xi^*(bbu)} = (10.21\pm 0.05)~GeV. The decay constant fBc=(2.94±0.21)fπf_{B_c} = (2.94 \pm 0.21) f_\pi is well determined from QSSR and leads to: Γ(Bc→Μττ)=(3.0±0.4)(Vcb/0.037)2\Gamma(B_c \rightarrow \nu_\tau \tau) = (3.0 \pm 0.4)( V_{cb}/0.037 )^2 ×1010\times 10^{10} s−1^{-1}.The uses of the vertex sum rules for the semileptonic decays of the BcB_c show that the tt-dependence of the form factors is much stronger than predicted by vector meson dominance. It also predicts the almost equal strength of about 0.30 ×1010\times 10^{10} sec−1^{-1} for the semileptonic rates BcB_c into Bs,Bs∗,ηcB_s, B^*_s,\eta_c and J/ψ\psi. Besides these phenomenological results, we also show explicitly how the Wilson coefficients of the ⟚αsG2⟩\langle\alpha_s G^2\rangle and ⟹G3⟩\langle G^3\rangle gluon condensates already contain the full heavy quark- (⟹QˉQ⟩\langle\bar QQ\rangle) and mixed- (⟹QˉGQ⟩\langle\bar QGQ\rangle) condensate contributions in the OPE.}Comment: 32 pages, LaTeX, no changes in the 1994 paper, latex errors corrected in 201

    Electromagnetic Form Factors in the hypercentral CQM

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    We report on the recent results of the hypercentral Constituent Quark Model (hCQM). The model contains a spin independent three-quark interaction which is inspired by Lattice QCD calculations and reproduces the average energy values of the SU(6) multiplets. The splittings are obtained with a SU(6)-breaking interaction, which can include also an isospin dependent term. Concerning Constituent Quark models, we have shown for the first time that the decreasing of the ratio of the elastic form factors of the proton is due to relativistic effects using relativistic corrections to the e.m. current and boosts. Now the elastic nucleon form factors have been recalculated, using a relativistic version of the hCQM and a relativistic quark current showing a very detailed reproduction of all the four form factor existing data over the complete range of 0-4 GeV2GeV^2. Futhermore, the model has been used for predictions concerning the electromagnetic transverse and longitudinal transition form factors giving a good description of the medium Q2Q^2 behaviour. We show that the discrepancies in the reproduction of the helicity amplitudes at low Q2Q^2 are due to pion loops. We have calculated the helicity amplitudes for all the 3 and 4 star resonances opening the possibility of application to the evaluation of cross sections.Comment: 5 pages, 7 figures, Invited talk at the ICTP 4th International Conference on Perspectives in Hadronic Physics, Trieste, Italy, 12-16 May 2003. Accepted by Eur. Phys. J.

    Living with interpersonal data: observability and accountability in the age of pervasive ICT

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    The Internet of Things, alongside existing mobile digital technologies, heralds a world in which pervasive sensing constantly captures data about us. Simultaneous with this technology programme are moves by policymakers to shore up the digital economy through the legislating of new trust-building models of data management. These moves seek to give individuals control and oversight of their personal data. Within shared settings, the consequences of these changes are the large-scale generation of interpersonal data generated by and acting on the group rather than individual. We consider how such systems create new forms of observability and hence accountability among members of the home, and draw on the work of Simmel and Goffman to explore how these demands are managed. Such management mitigates the more extreme possibilities for domestic monitoring posited by these systems, yet without careful design there remains a considerable danger of unanticipated negative consequences

    Search for Flavoured Multiquarks in a Simple Bag Model

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    We use a bag model to study flavoured mesonic (Qqqˉqˉ)(Qq\bar q\bar q) and baryonic (Q‟qqqq)({\overline Q}qqqq) states, where one heavy quark QQ is associated with light quarks or antiquarks, and search for possible stable multiquarks. No bound state is found. However some states lie not too high above their dissociation threshold, suggesting the possibility of resonances, or perhaps bound states in improved models.Comment: REVTEX, VERSION 3.

    Refractive Index of Humid Air in the Infrared: Model Fits

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    The theory of summation of electromagnetic line transitions is used to tabulate the Taylor expansion of the refractive index of humid air over the basic independent parameters (temperature, pressure, humidity, wavelength) in five separate infrared regions from the H to the Q band at a fixed percentage of Carbon Dioxide. These are least-squares fits to raw, highly resolved spectra for a set of temperatures from 10 to 25 C, a set of pressures from 500 to 1023 hPa, and a set of relative humidities from 5 to 60%. These choices reflect the prospective application to characterize ambient air at mountain altitudes of astronomical telescopes.Comment: Corrected exponents of c0ref, c1ref and c1p in Table

    Enabling quantitative data analysis through e-infrastructures

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    This paper discusses how quantitative data analysis in the social sciences can engage with and exploit an e-Infrastructure. We highlight how a number of activities which are central to quantitative data analysis, referred to as ‘data management’, can benefit from e-infrastructure support. We conclude by discussing how these issues are relevant to the DAMES (Data Management through e-Social Science) research Node, an ongoing project that aims to develop e-Infrastructural resources for quantitative data analysis in the social sciences

    Scalar mesons in the Nambu--Jona-Lasinio model with 't Hooft interaction

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    We calculate the mass spectra of the pseudoscalar and scalar meson nonets in the Nambu--Jona-Lasinio model with the 't Hooft interaction. We obtain satisfactory result for the pseudoscalar mesons. For the scalar mesons, the 't Hooft interaction somewhat increases the values of the masses. However, it is not sufficient to explain the whole scalar mass spectrum. The situation could be improved for the σ\sigma and f0f_0 mesons through mixing with the glueball state. For the description of the masses of a0a_0 and \kstar mesons, it is necessary to involve the other models. The strong decay widths of the scalar mesons are described.Comment: LaTeX text, 8 page

    New Horizons in the use of routine data for ageing research

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    The past three decades have seen a steady increase in the availability of routinely collected health and social care data and the processing power to analyse it. These developments represent a major opportunity for ageing research, especially with the integration of different datasets across traditional boundaries of health and social care, for prognostic research and novel evaluations of interventions with representative populations of older people. However, there are considerable challenges in using routine data at the level of coding, data analysis and in the application of findings to everyday care. New Horizons in applying routine data to investigate novel questions in ageing research require a collaborative approach between clinicians, data scientists, biostatisticians, epidemiologists and trial methodologists. This requires building capacity for the next generation of research leaders in this important area. There is a need to develop consensus code lists and standardised, validated algorithms for common conditions and outcomes that are relevant for older people to maximise the potential of routine data research in this group. Lastly, we must help drive the application of routine data to improve the care of older people, through the development of novel methods for evaluation of interventions using routine data infrastructure. We believe that harnessing routine data can help address knowledge gaps for older people living with multiple conditions and frailty, and design interventions and pathways of care to address the complex health issues we face in caring for older people
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