629,380 research outputs found

    Strange form factors of the nucleon in a two-component model

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    The strange form factors of the nucleon are studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. A comparison with the available experimental world data from the SAMPLE, PVA4, HAPPEX and G0 collaborations shows a good overall agreement. The strange magnetic moment is found to be positive, 0.315 nm.Comment: 11 pages, 2 tables, 5 figures, accepted for publication in J. Phys. G. Revised version, new figures, extra table, new results, updated reference

    Extracting nucleon strange and anapole form factors from world data

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    The complete world set of parity violating electron scattering data up to Q^2~0.3 GeV^2 is analysed. We extract the current experimental determination of the strange electric and magnetic form factors of the proton, as well as the weak axial form factors of the proton and neutron, at Q^2 = 0.1 GeV^2. Within experimental uncertainties, we find that the strange form factors are consistent with zero, as are the anapole contributions to the axial form factors. Nevertheless, the correlation between the strange and anapole contributions suggest that there is only a small probability that these form factors all vanish simultaneously.Comment: 4 pages, 3 figs; v2: version to appear in PR

    Strange Assemblage

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    This paper contends that the power of Deleuze & Guattari’s (1988) notion of assemblage as theorised in 1000 Plateaus can be normalised and reductive with reference to its application to any social-cultural context where an open system of dynamic and fluid elements are located. Rather than determining the assemblage in this way, this paper argues for an alternative conception of ‘strange assemblage’ that must be deliberately and consciously created through rigorous and focused intellectual, creative and philosophical work around what makes assemblages singular. The paper will proceed with examples of ‘strange assemblage’ taken from a film by Peter Greenaway (A Zed and 2 Noughts); the film ‘Performance’; educational research with Sudanese families in Australia; the book, Bomb Culture by Jeff Nuttall (1970); and the band Hawkwind. Fittingly, these elements are themselves chosen to demonstrate the concept of ‘strange assemblage’, and how it can be presented. How exactly the elements of a ‘strange assemblage’ come together and work in the world is unknown until they are specifically elaborated and created ‘in the moment’. Such spontaneous methodology reminds us of the 1960s ‘Happenings’, the Situationist International and Dada/Surrealism. The difference that will be opened up by this paper is that all elements of this ‘strange assemblage’ cohere in terms of a rendering of ‘the unacceptable.'

    Phase Space Reconstruction from Economic Time Series Data: Improving Models of Complex Real-World Dynamic Systems

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    Failure of economic models to anticipate the global financial crisis illustrates the need for modeling to better capture complex real-world dynamics. Conventional models—in which economic variables evolve toward equilibria or fluctuate about equilibria in response to exogenous random shocks—are ill-equipped to portray complex real-world dynamics in which economic variables may cycle aperiodically along low-dimensional ‘strange attractors’. We present a method developed in the physics literature—‘phase space reconstruction’—that reconstructs strange attractors present in real-world dynamical systems using time series data on a single variable. Phase space reconstruction provides pictures of real-world dynamics that can guide model specificationphase space reconstruction, time series data, economic dynamics, Agribusiness, Agricultural and Food Policy, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Production Economics, Risk and Uncertainty,

    Flavor content of nucleon form factors in a VMD approach

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    The strange form factors of the nucleon are studied in a two-component model consisting of a three-quark intrinsic structure surrounded by a meson cloud. A comparison with the available experimental world data from the SAMPLE, PVA4, HAPPEX and G0 collaborations shows a good overall agreement. It is shown that the strangeness contribution to the electric and magnetic form factors is of the order of a few percent. In particular, the strange quark contribution to the charge radius is small (0.005 fm**2) and to the magnetic moment it is positive (0.315 n.m.).Comment: 5 pages, 6 figures, 1 table, invited talk at PAVI06, Milos, Greece, May 16-20, 200

    New analysis concerning the strange quark polarization puzzle

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    The fact that analyses of semi-inclusive deep inelastic scattering suggest that the polarized strange quark density Δs(x)+Δsˉ(x)\Delta s(x) + \Delta \bar{s}(x) is positive in the measured region of Bjorken x, whereas all analyses of inclusive deep inelastic scattering yield significantly negative values of this quantity, is known as the "strange quark polarization puzzle". We have analyzed the world data on inclusive deep inelastic scattering, including the COMPASS 2010 proton data on the spin asymmetries, and for the first time, the new extremely precise JLab CLAS data on the proton and deuteron spin structure functions. Despite allowing in our parametrization, for a possible sign change, our results confirm that the inclusive data yield significantly negative values for the polarized strange quark density.Comment: 8 pages, 3 figures, 3 tables; misprints for the values of χ2/DOF\chi^2/DOF in page 5 correcte

    NuTeV Anomaly & Strange-Antistrange Asymmetry

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    The NuTeV Collaboration reported a value of sin⁥2Ξw\sin^{2}\theta_{w} measured in neutrino-nucleon deep inelastic scattering, and found that the value is three standard deviations from the world average value of other electroweak measurements. If this result cannot be explained within conventional physics, it must imply some novel physics beyond the standard model. We report the correction from the asymmetric strange-antistrange sea by using both the light-cone baryon-meson fluctuation model and the chiral quark model, and show that a significant part of the NuTeV anomaly can be explained by the strange-antistrange asymmetry.Comment: 4 pages, 2 figures. Talk at ICHEP04, August 16-22, 2004, Beijing, Chin

    Gothic Cordelias: The Afterlife of Lear and the Construction of Femininity

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    Addresses the gap for an analysis of Shakespeare\u27s relation to the Gothic. The Gothic novel transports you to a strange and fascinating world quite unlike your own, far away from the calm drawing rooms of Regency England. It is the ultimate escapist literature. It is this world, and its mutually beneficial relationship with Catholicism, that Dr Maria Purves so beautifully illuminates for the reader

    The CFL phase and m_s: An effective field theory approach

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    We study the phase diagram of dense quark matter with an emphasis on the role of the strange quark mass. Our approach is based on two effective field theories (EFTs). The first is an EFT that describes quark quasi-particles near the Fermi surface. This EFT is valid at energies small compared to the chemical potential. The second is an EFT for the Goldstone modes in the paired phase. We find that in response to a non-zero strange quark mass the CFL phase first undergoes a transition to a kaon condensed phase, and then to a gapless phase with a non-zero Goldstone boson current.Comment: 26 pages, to appear in ``Pairing in fermionic systems: Basic concepts and modern applications", Series on Advances in Quantum Many-Body Theory, Vol. 8, World Scientific Publishing, Singapor
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