2,263 research outputs found

    Results of a fish health survey of North Biscayne Bay, June 1976-June 1977

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    Fish were collected weekly in Biscayne Bay using a monofilament gill net set from a small skiff during 20-30 minute intervals. Although weekly sampling took place for 2.5 years, only the data from samples collected from June 1976 to June 1977 were used in this document. Abnormal external conditions of fins and body were observed on each fish and recorded. Fish were returned immediately to their habitats. Fish collected in the time period for this study numbered 3,765 and included 32 species. Of these, 16 species, totaling 3,556 fish, were caught in sufficient numbers (20 or more) to warrant data analysis. Only 3 of the 16 species could be considered relatively unafflicted: Aetobatus narinari (spotted eagle ray), Diodon hystrix (porcupinefish), and Selene vomer (lookdown). More than 80% of the examined specimens of these three species were unaffected. Less than 20% of the specimens of Diapterus plumieri (striped mojarra), Micropogonias undulatus (Atlantic croaker), and Pogonias cromis (black drum) displayed normal conditions. The three most afflicted species were Diapterus plumieri, striped mojarra; Micropogonias undulatus, Atlantic croaker; and Pogonias cromis, black drum. Only 7, 3, and 7% respectively showed no external evidence of disease. Data described in this document were originally tabulated in the mid-1970s, remained unpublished, and are no longer available. This document was based on archived unpublished text, a data summary table, and figures. Most of the text and cited references were the ones used in the original manuscript and no attempt was made to update them. (PDF contains 44 pages

    Prospects for Direct CP Violaton in Exclusive and Inclusive Charmless B decays

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    Within the Standard Model, CP rate asymmetries for B→K−π+,0B\to K^-\pi^{+,0} could reach 10%. With strong final state phases, they could go up to 20--30%, even for Kˉ0π−\bar K^0\pi^- mode which would have opposite sign. We can account for K−π+K^-\pi^{+}, Kˉ0π−\bar K^0\pi^- and ϕK\phi K rate data with new physics enhanced color dipole coupling and destructive interference. Asymmetries could reach 40--60% for KπK\pi and ϕK\phi K modes and are all of the same sign. We are unable to account for K−π0K^-\pi^0 rate. Our inclusive study supports our exclusive results.Comment: Minor changes, correct a small bug in Fig. 1(b). Version to appear in Phys. Rev. Let

    An imaging time-of-propagation system for charged particle identification at a super B factory

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    Super B factories that will further probe the flavor sector of the Standard Model and physics beyond will demand excellent charged particle identification (PID), particularly K/pi separation, for momenta up to 4 GeV/c, as well as the ability to operate under beam backgrounds significantly higher than current B factory experiments. We describe an Imaging Time-of-Propagation (iTOP) detector which shows significant potential to meet these requirements. Photons emitted from charged particle interactions in a Cerenkov radiator bar are internally reflected to the end of the bar, where they are collected on a compact image plane using photodetectors with fine spatial segmentation in two dimensions. Precision measurements of photon arrival time are used to enhance the two dimensional imaging, allowing the system to provide excellent PID capabilities within a reduced detector envelope. Results of the ongoing optimization of the geometric and physical properties of such a detector are presented, as well as simulated PID performance. Validation of simulations is being performed using a prototype in a cosmic ray test stand at the University of Hawaii.Comment: 3 pages, 5 figures, submitted to TIPP09 proceeding

    Model-independent analysis of \bbox{B}-\bbox{\bar B} mixing and \bbox{CP} violation in \bbox{B} decays

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    We present a framework to analyze effects of new physics beyond the standard model on BB-Bˉ\bar B mixing and CPCP violation in BB decays in a model-independent manner. Assuming that tree level decay amplitudes are dominated by the standard model ones, new physics contribution to the BB-Bˉ\bar B mixing can be extracted from several measurements at BB factories. Using this framework, we show the present constraint on new physics contribution to the BB-Bˉ\bar B mixing, and illustrate constraints expected to be given by future experiments at BB factories. We also point out a possibility that CPCP asymmetries in B→ψKSB\rightarrow\psi K_S, B→ππB\rightarrow\pi\pi, and B→DKB\rightarrow DK modes look consistent with the standard model, even if a large new physics contribution is present in the BB-Bˉ\bar B mixing.Comment: 11 pages, 3 Postscript figures, also available via anonymous ftp at ftp://ftp.kek.jp/kek/preprints/TH/TH-44

    B-> K photon photon via intermediate eta'

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    We examine our previous conjecture that the eta' intermediate resonance has the dominant role in the long distance contributions to B decay into two photons and a strange final state hadron. We calculate the branching ratio of the exclusive B-> K eta'-> K photon photon decay using the nonspectator mechanism for eta' production in charmless hadronic B decays. It is shown that the obtained branching ratio B^eta'(B-> K\gamma\gamma)~ 8.7 X 10^{-7} is more than twice as large as the eta_c contribution to this decay mode.Comment: 6 pages, latex, no figure

    A relativistic chiral quark model for pseudoscalar emission from heavy mesons

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    The amplitudes for one-pion mediated transitions between heavy meson excited states are obtained in the framework of the relativistic chiral quark model. The effective coupling constants to pions and the decay widths of excited heavy mesons with l<=2 for non-radially excited, and the l=0 radially excited mesons are presented for both charmed and beauty mesons. We also discuss the allowed decays of strange excited heavy mesons by emission of a K-meson.Comment: 20 pages, revte

    CP-Violating Observables in Tagged D0D^0--Dˉ0\bar{D}^0 Decays

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    We perform a systematic study of CP-violating observables in \ddbar\ decays. We show that given a final state, which may be a CP eigenstate or not, all the observables can in principle be measured if decay-time information is available and if, for CP non-eigenstates, both decay rates into ff and fˉ\bar f are considered. As an illustration of our analysis we discuss an effective superweak scenario.Comment: 9 pages LATEX, no figure

    On the algebraic K-theory of the complex K-theory spectrum

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    Let p>3 be a prime, let ku be the connective complex K-theory spectrum, and let K(ku) be the algebraic K-theory spectrum of ku. We study the p-primary homotopy type of the spectrum K(ku) by computing its mod (p,v_1) homotopy groups. We show that up to a finite summand, these groups form a finitely generated free module over a polynomial algebra F_p[b], where b is a class of degree 2p+2 defined as a higher Bott element.Comment: Revised and expanded version, 42 pages

    Measuring V_ub and probing SUSY with double ratios of purely leptonic decays of B and D mesons

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    The experimental prospects for precise measurements of the leptonic decays B_u -> tau nu / mu nu, B_s -> mu+ mu-, D -> mu nu and D_s -> mu nu / tau nu are very promising. Double ratios involving four of these decays can be defined in which the dependence on the values of the decay constants is essentially eliminated, thus enabling complementary measurements of the CKM matrix element V_ub with a small theoretical error. We quantify the experimental error in a possible future measurement of |V_ub| using this approach, and show that it is competitive with the anticipated precision from the conventional approaches. Moreover, it is shown that such double ratios can be more effective than the individual leptonic decays as a probe of the parameter space of supersymmetric models. We emphasize that the double ratios have the advantage of using |V_ub| as an input parameter (for which there is experimental information), while the individual decays have an uncertainty from the decay constants (e.g. f_B_s), and hence a reliance on theoretical techniques such as lattice QCD.Comment: 21 pages, 4 figure
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