57 research outputs found

    Enhanced Direct CP Violation in B±→ρ0π±B^{\pm} \to \rho^{0} \pi^{\pm}

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    We study direct CP violation in the hadronic decay B±→ρ0π±B^{\pm} \to \rho^{0}\pi^{\pm}, including the effect of ρ−ω\rho - \omega mixing. We find that the CP violating asymmetry is strongly dependent on the CKM matrix elements, especially the Wolfenstein parameter η\eta. For fixed NcN_{c} (the effective parameter associated with factorization), the CP violating asymmetry, aa, has a maximum of order 3030%-50% when the invariant mass of the π+π−\pi^{+}\pi^{-} pair is in the vicinity of the ω\omega resonance. The sensitivity of the asymmetry, aa, to NcN_{c} is small. Moreover, if NcN_{c} is constrained using the latest experimental branching ratios from the CLEO collaboration, we find that the sign of sin⁥Ύ\sin \delta is always positive. Thus, a measurement of direct CP violation in B±→ρ0π±B^{\pm} \to \rho^{0}\pi^{\pm} would remove the mod(π)(\pi) ambiguity in arg[−VtdVtb⋆VudVub⋆]{\rm arg}[ - \frac{V_{td}V_{tb}^{\star}}{V_{ud}V_{ub}^{\star}}].Comment: 37 pages, 7 figure

    Rescaling employment support accountability: from negative national neoliberalism to positively integrated city-region ecosystems

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    Waves of successive Devolution Deals are transforming England’s landscape of spatial governance and transferring new powers to city-regions, facilitating fundamental qualitative policy reconfigurations and opening up new opportunities as well as new risks for citizens and local areas. Focused on city-region’s recently emerging roles around employment support policies the article advances in four ways what are currently conceptually and geographically underdeveloped literatures on employment support accountability levers. Firstly, the paper dissects weaknesses in the accountability framework of Great Britain’s key national contracted-out employment support programme and identifies the potential for city-regions to respond to these weaknesses. Secondly, the article highlights the centrality of the nationally neglected network accountability lever in supporting these unemployed individuals and advances this discussion further by introducing to the literature for the first time a conceptual distinction between what we term ‘positive’ and ‘negative’ forms of these accountably levers that currently remain homogenised within the literature. Crucially, the argument sets out for the first time in the literature why analytically it is the positive version of network accountability that is the key – and currently missing at national-level – ingredient to the design of effective employment support for the priority group of ‘harder-to-help’ unemployed people who have more complex and/or severe barriers to employment. Thirdly, the paper argues from a geographical perspective that it is city-regions that are uniquely positioned in the English context to create the type of positively networked integrated employment support ‘ecosystem’ that ‘harder-to-help’ individuals in particular require. Finally, the discussion situates these city-region schemes within their broader socio-economic and political context and connects with broader debates around the lurching development of neoliberalism. In doing so it argues that whilst these emerging city-region ecosystem models offer much progressive potential their relationship to the problematic neoliberal employment support paradigm remains uncertain given that they refine, embed and indeed buttress that same neoliberal employment policy paradigm rather than fundamentally challenging or stepping beyond it

    Observing Direct CP Violation in Untagged B-Meson Decays

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    Direct CP violation can exist in untagged B-meson decays to self-conjugate, three-particle final states; it would be realized as a population asymmetry in the untagged decay rate across the mirror line of the Dalitz plot of the three-body decay. We explore the numerical size of this direct CP-violating effect in a variety of B-meson decays to three pseudoscalar mesons; we show that the resulting asymmetry is comparable to the partial rate asymmetry in the analogous tagged decays, making the search for direct CP violation in the untagged decay rate, for which greater statistics accrue, advantageous.Comment: 31 pages, REVTeX4, 1 eps figure, references added, typos corrected, version to appear in PR

    Final-State Phases in Charmed Meson Two-Body Nonleptonic Decays

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    Observed decay rates indicate large phase differences among the amplitudes for the charge states in D→KˉπD \to \bar K \pi and D→Kˉ∗πD \to \bar K^* \pi but relatively real amplitudes in the charge states for D→KˉρD \to \bar K \rho. This feature is traced using an SU(3) flavor analysis to a sign flip in the contribution of one of the amplitudes contributing to the latter processes in comparison with its contribution to the other two sets. This amplitude may be regarded as an effect of rescattering and is found to be of magnitude comparable to others contributing to charmed particle two-body nonleptonic decays.Comment: 19 pages, latex, 4 figures, to be submitted to Phys. Rev.

    Measurement of the CP Violation Parameter sin(2phi_1) in B^0_d Meson Decays

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    We present a measurement of the Standard Model CP violation parameter sin(2phi_1) based on a 10.5 fb^{-1} data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e+e- collider. One neutral B meson is reconstructed in the J/psi K_S, psi(2S) K_S, chi_{c1} K_S, eta_c K_S, J/psi K_L or J/psi pi^0 CP-eigenstate decay channel and the flavor of the accompanying B meson is identified from its charged particle decay products. From the asymmetry in the distribution of the time interval between the two B-meson decay points, we determine sin(2phi_1) = 0.58 +0.32-0.34 (stat) +0.09-0.10 (syst).Comment: LaTex, 13 pages, 3 figures, submitted to P.R.

    Citizens, consumers and the citizen-consumer: articulating the interests at stake in media and communications regulation

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    The Office of Communications (Ofcom), established by an Act of Parliament in 2003, is a new sector wide regulator in the UK, required to further the interests of what has been termed the ‘citizen-consumer’. Using a critical discursive approach, this article charts the unfolding debate among stakeholders in the new regulatory environment as they attempt to define the interests of citizens, consumers and the citizen-consumer. Ofcom has preferred to align the terms ‘citizen’ and ‘consumer’ so that the interests of both may be met, as far as possible, through an economic agenda of market regulation. Among civil society groups, there is growing concern that the citizen interest is becoming marginalised as the consumer discourse becomes more widespread. We conclude by advocating the development of a positive definition of the citizen interests, distinct from the consumer interests, for the media and communications environment

    Heat flow in the Trans-Hudson orogen of the Canadian Shield: implications for Proterozoic continental growth

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    International audienceFourteen new heat flow and radiogenic heat production measurements have been obtainedi n the Paleo-ProterozoicT rans-HudsonO rogeno f the Canadian Shield. This orogen, which consists of several distinctive belts, corresponds to a pulse of crustal growth through island arc magmatism between 1.9 and 1.8 Ga. The data now available include 17 previously published measurements. Heat flow variations that are related to the history of magmatism and internal differentiation of the belts provide constraintso n the crustal assemblageisn the different belts of the orogen. The average and standard deviation of heat flow values for the entire orogen4, 25:11m W m- 2, are identical to those of the older Superior Province and of the younger Grenville Province. For the orogen as a whole, heat flow is weakly correlated to the heat production of surface rocks. High heat flow values are found in the Thompson belt, consisting of metasedimentary rocks deposited on the ancient continental margin of the Superior craton. There the accumulation of sediments derived from older and differentiated continental upper crust has resulted in significant concentrations of radioelements in large volumes of rocks. The heat flow is low in the belts that expose juvenile Proterozoic crust consisting mostly of arc-related volcanic rocks. In the Flin Flon-Snow Lake Belt, the average heat flow is the same as the average of the orogen. The low heat production and the lack of correlation between heat flow and heat production suggest that the supracrustal volcanics exposed a,t the surface are thin and rest on a basement richer in radioelements. In the Lynn Lake belt, the heat flow is significantly lower than the average for the orogen although the surface heat production is not low. The heat flow data require a thin (<10 kin) surface layer overlying the mid and lower crust depleted in ra.d ioelements. Around the town of Lynn Lake, heat flow is consistently low over a distance of m40 kin. The coincidence between this "cold spot" and anomalouslyt hick crust suggeststh at deep crustal roots may be preserved because of the stronger rheology implied by the low temperatures. The evolution of the Trans-Hudson Orogen exemplifiest he interplay between the processes generating rocks of evolved composition, which require crustal thickening, and those forming "normal" continental crust with average thickness, which require crustal flow and soft crustal rheology
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