Bose-Einstein correlations in WW events at LEP

The current status of the LEP results on Bose-Einstein correlations is discussed. Emphasis is given to the measurement of Bose-Einstein correlations between decay products from different W's, in an energy range between 172 and 209 GeV, dependent on the experiment. For the first time all four LEP experiments conclude that no evidence for correlations between pions from different W's is seen at the current level of precision.Comment: 6 pages, 4 figures, Talk given at XXXVI Rencontres de Moriond, Les Arcs, France, March 17-24 200

Bose-Einstein correlations in WW pair production at LEP

This paper presents an overview of the latest results from the L3 and DELPHI collaborations concerning the measurement of Bose-Einstein correlations between identical bosons coming from different W's in fully hadronic WW decays. Using the same method, L3 sees no indication of any inter-W BEC effect, while DELPHI reports an indication of inter-W BEC between like-charged particles of the order of three standard deviations.Comment: 5 pages, 4 figures, Talk given at the XXXVIIIth Rencontres de Moriond (QCD), Les Arcs, France, March 22-29 200

The emerging practice of food forest - a promise for a sustainable urban food system?

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Multichannel calculation of excited vector ϕ\phi resonances and the ϕ(2170)\phi(2170)

A multichannel calculation of excited $J^{PC}=1^{--}$ $\phi$ states is carried out within a generalization of the Resonance-Spectrum Expansion, which may shed light on the classification of the $\phi(2170)$ resonance, discovered by BABAR and originally denoted X(2175). In this framework, a complete spectrum of bare $s\bar{s}$ states is coupled to those OZI-allowed decay channels that should be most relevant for the considered energy range. The included $S$- and $P$-wave two-meson channels comprise the lowest pseudoscalar, vector, scalar, and axial-vector mesons, while in the $q\bar{q}$ sector both the $^{3}S_1$ and $^{3}D_1$ states are coupled. The only two free parameters are tuned so as to reproduce mass and width of the $\phi(1020)$, but come out reasonably close to previously used values. Among the model's $T$-matrix poles, there are good candidates for observed resonances, as well other ones that should exist according to the quark model. Besides the expected resonances as unitarized confinement states, a dynamical resonance pole is found at $(2186-i246)$ MeV. The huge width makes its interpretation as the $\phi(2170)$ somewhat dubious, but further improvements of the model may change this conclusion.Comment: 6 pages, 5 figures, RevTex4; v2: very recent experimental result, some extra discussion, and 2 references added; v3: 3 new figures, 2 new equations, and some rephrasing; version accepted for publication in Phys. Rev.

Lecture notes on ridge regression

The linear regression model cannot be fitted to high-dimensional data, as the high-dimensionality brings about empirical non-identifiability. Penalized regression overcomes this non-identifiability by augmentation of the loss function by a penalty (i.e. a function of regression coefficients). The ridge penalty is the sum of squared regression coefficients, giving rise to ridge regression. Here many aspect of ridge regression are reviewed e.g. moments, mean squared error, its equivalence to constrained estimation, and its relation to Bayesian regression. Finally, its behaviour and use are illustrated in simulation and on omics data. Subsequently, ridge regression is generalized to allow for a more general penalty. The ridge penalization framework is then translated to logistic regression and its properties are shown to carry over. To contrast ridge penalized estimation, the final chapter introduces its lasso counterpart

Equation of state in the inner crust of neutron stars: discusion of the unbound neutron states

In this paper, we calculate the stable Wigner-Seitz (W-S) cells in the inner crust of neutron stars and we discuss the nuclear shell effects. A distinction is done between the shell effects due to the bound states and those induced by the unbound states, which are shown to be spurious. We then estimate the effects of the spurious shells on the total energy and decompose it into a smooth and a residual part. We propose a correction to the Hartree-Fock binding energy in Wigner-Seitz cell (HF-WS).Comment: conference EXOCT07, Catania, 11-15 June, 200

Seagull and pion-in-flight currents in neutrino-induced 1N1N and 2N2N knockout

[Background] The neutrino-nucleus ($\nu A$) cross section is a major source of systematic uncertainty in neutrino-oscillation studies. A precise $\nu A$ scattering model, in which multinucleon effects are incorporated, is pivotal for an accurate interpretation of the data. [Purpose] In $\nu A$ interactions, meson-exchange currents (MECs) can induce two-nucleon ($2N$) knockout from the target nucleus, resulting in a two-particle two-hole (2p2h) final state. They also affect single nucleon ($1N$) knockout reactions, yielding a one-particle one-hole (1p1h) final state. Both channels affect the inclusive strength. We present a study of axial and vector, seagull and pion-in-flight currents in muon-neutrino induced $1N$ and $2N$ knockout reactions on $^{12}$C. [Method] Bound and emitted nucleons are described as Hartree-Fock wave functions. For the vector MECs, the standard expressions are used. For the axial current, three parameterizations are considered. The framework developed here allows for a treatment of MECs and short-range correlations (SRCs). [Results] Results are compared with electron-scattering data and with literature. The strengths of the seagull, pion-in-flight and axial currents are studied separately and double differential cross sections including MECs are compared with results including SRCs. A comparison with MiniBooNE and T2K data is presented. [Conclusions] In the 1p1h channel, the effects of the MECs tend to cancel each other, resulting in a small effect on the double differential cross section. $2N$ knockout processes provide a small contribution to the inclusive double differential cross section, ranging from the $2N$ knockout threshold into the dip region. A fair agreement with the MiniBooNE and T2K data is reached.Comment: 16 pages, 10 figure

Organizing Multidisciplinary Care for Children with Neuromuscular Diseases

The Academic Medical Center (AMC) in Amsterdam, The Netherlands, recently opened the `Children's Muscle Center Amsterdam' (CMCA). The CMCA diagnoses and treats children with neuromuscular diseases. These patients require care from a variety of clinicians. Through the establishment of the CMCA, children and their parents will generally visit the hospital only once a year, while previously they visited on average six times a year. This is a major improvement, because the hospital visits are both physically and psychologically demanding for the patients. This article describes how quantitative modelling supports the design and operations of the CMCA. First, an integer linear program is presented that selects which patients to invite for a treatment day and schedules the required combination of consultations, examinations and treatments on one day. Second, the integer linear program is used as input to a simulation to study to estimate the capacity of the CMCA, expressed in the distribution of the number patients that can be seen on one diagnosis day. Finally, a queueing model is formulated to predict the access time distributions based upon the simulation outcomes under various demand scenarios