Hybrid meson production by electromagnetic and weak interactions in a flux-tube simulation of lattice QCD

We calculate rates for hybrid meson production by electromagnetic and weak interactions in the flux-tube model. Applications include photo and electroproduction at Jefferson Laboratory and HERA, and the production of light strange and charmed hybrids in the weak decays of heavy flavours. Photoproduction of some light hybrids is predicted to be prominent in charge exchange reactions, $\gamma p \to n \cal{H}$ and accessible in $\gamma p \to p \cal{H}$. Production of light or charmed hybrids in $B$ and $D$ decays may be feasible with high statistics. Photoproduction of the axial hybrid meson is predicted to be large courtesy of $\pi$ exchange, and its strange counterpart is predicted in $B \to \psi K_H(1^+)$ with $b.r. \sim 10^{-4}$. Production rates for exotic hybrid candidates $1^{-+};(0,2)^{+-}$ are given special attention. Selection rules that can help to distinguish between hybrid and conventional states with the same $J^{PC}$ are noted.Comment: uses psfrag; One reference correcte

Electroweak production of hybrid mesons in a Flux-Tube simulation of Lattice QCD

We make the first calculation of the electroweak couplings of hybrid mesons to conventional mesons appropriate to photoproduction and to the decays of $B$ or $D$ mesons. $E1$ amplitudes are found to be large and may contribute in charge exchange $\gamma p \to n H^+$ allowing production of (amongst others) the charged $1^{-+}$ exotic hybrid off $a_2$ exchange. Axial hybrid meson photoproduction is predicted to be large courtesy of $\pi$ exchange, and its strange hybrid counterpart is predicted in $B \to \psi K_H(1^+)$ with $b.r. \sim 10^{-4}$. Higher multipoles, and some implications for hybrid charmonium are briefly discussed.Comment: 4 page

Pentaquark Symmetries, Selection Rules and another potentially Narrow State

We identify essential differences between the pentaquark and chiral soliton models of \10bar$_5$ and {\bf 8}$_5$ pentaquarks and conventional {\bf 8}$_3$ states, which are experimentally measurable. We show how the decays of $\Xi_5$ states in particular can test models of the pentaquarks, recommend study of the relative branching ratios of e.g. $\Xi^{-}_5 \to \Xi^-\pi^0:\Xi^0\pi^-$, and predict that the decay amplitude $\Xi_5 \to \Xi^*\pi$ is zero at leading order in pentaquark models for any mixture of \10bar and the associated {\bf 8}$_5$. We also include a pedagogic discussion of wavefunctions in the pentaquark picture and show that pentaquark models have this {\bf 8}$_5$ with $F/D=1/3$, in leading order forbidding $\Xi_5 \to \Lambda K$. The role of Fermi-Dirac symmetry in the $qqqq$ wavefunction and its implications for the width of pentaquarks are briefly discussed. The relative couplings $g^2(\Theta_Q N K_Q^*)/g^2(\Theta_Q N K_Q) = 3$ for $Q \equiv s,c,b$. A further potentially narrow state $\Lambda$ in {\bf 8}$_5$ with $J^P = 3/2^+$ is predicted around 1650 MeV.Comment: Revised version, corrects PDF margin problems, minor changes to tex

Systems approach provides management control of complex programs

Integrated program management process provides management visual assistance through three interrelated charts - system model that identifies each function to be performed, matrix that identifies personnel responsibilities for these functions, process chart that breaks down the functions into discrete tasks

Options for the SELEX state D_{s\J}^+(2632)

We consider possible assignments for the D_{s\J}^+(2632), which was recently reported in D$_s^+\eta$ and D$^0$K$^+$ final states by the SELEX Collaboration at Fermilab. The most plausible quark model assignment for this state is the first radial excitation ($2^3\S_1$) of the $c\bar s$ D$_s^*(2112)$, although the predicted mass and strong decay branching fractions for this assignment are not in agreement with the SELEX data. The reported dominance of D$_s\eta$ over DK appears especially problematic. An intriguing similarity to the K$^*(1414)$ is noted. $2^3\S_1$--^3\D_1 configuration mixing is also considered, and we find that this effect is unlikely to resolve the branching fraction discrepancy. Other interpretations as a $c\bar s$-hybrid or a two-meson molecule are also considered, but appear unlikely. Thus, if this state is confirmed, it will require reconsideration of the systematics of charmed meson spectroscopy and strong decays.Comment: 6 revtex4 pages, 2 eps figure

S and D-wave phase shifts in isospin-2 pi pi scattering from lattice QCD

The isospin-2 pi pi system provides a useful testing ground for determining elastic hadron scattering parameters from finite-volume spectra obtained using lattice QCD computations. A reliable determination of the excited state spectrum of two pions in a cubic box follows from variational analysis of correlator matrices constructed using a large basis of operators. A general operator construction is presented which respects the symmetries of a multi-hadron system in flight. This is applied to the case of pi pi and allows for the determination of the scattering phase-shifts at a large number of kinematic points, in both S-wave and D-wave, within the elastic region. The technique is demonstrated with a calculation at a pion mass of 396 MeV, where the elastic scattering is found to be well described by a scattering length parameterisation.Comment: Tables of little-group CGCs in ancillary file; v2: minor changes to reflect published versio

Exotic and excited-state radiative transitions in charmonium from lattice QCD

We compute, for the first time using lattice QCD methods, radiative transition rates involving excited charmonium states, states of high spin and exotics. Utilizing a large basis of interpolating fields we are able to project out various excited state contributions to three-point correlators computed on quenched anisotropic lattices. In the first lattice QCD calculation of the exotic 1-+ eta_c1 radiative decay, we find a large partial width Gamma(eta_c1 -> J/psi gamma) ~ 100 keV. We find clear signals for electric dipole and magnetic quadrupole transition form factors in chi_c2 -> J/psi gamma, calculated for the first time in this framework, and study transitions involving excited psi and chi_c1,2 states. We calculate hindered magnetic dipole transition widths without the sensitivity to assumptions made in model studies and find statistically significant signals, including a non-exotic vector hybrid candidate Y_hyb? -> eta_c gamma. As well as comparison to experimental data, we discuss in some detail the phenomenology suggested by our results and the extent to which it mirrors that of quark potential models and make suggestions for the interpretation of our results involving exotic quantum numbered states

A Novel Hybrid CNN-AIS Visual Pattern Recognition Engine

Machine learning methods are used today for most recognition problems. Convolutional Neural Networks (CNN) have time and again proved successful for many image processing tasks primarily for their architecture. In this paper we propose to apply CNN to small data sets like for example, personal albums or other similar environs where the size of training dataset is a limitation, within the framework of a proposed hybrid CNN-AIS model. We use Artificial Immune System Principles to enhance small size of training data set. A layer of Clonal Selection is added to the local filtering and max pooling of CNN Architecture. The proposed Architecture is evaluated using the standard MNIST dataset by limiting the data size and also with a small personal data sample belonging to two different classes. Experimental results show that the proposed hybrid CNN-AIS based recognition engine works well when the size of training data is limited in siz

The "forbidden" decays of hybrid mesons to πρ\pi \rho can be large

The observation of $\pi_1(1600) \to \pi \rho$ is shown in the flux-tube model to be compatible with this state being a hybrid meson with branching ratio to this channel $\sim 30$. The $\pi \rho$ widths of other hybrids are related by rather general arguments. These results enable cross sections for photoproduction of hybrids to be predicted.Comment: Replaced with revised version correcting a technical mistake, conclusions remain unchanged. Accepted for publication in PR

Progress in caustic dezincing of galvanized scrap

In response to the worldwide increase in consumption of galvanized steel for automobiles in the last fifteen years, and the cost of environmental compliance associated with remelting larger quantities of galvanized steel scrap, processes are being developed to separate and recover the steel and zinc from galvanized ferrous scrap. In the process discussed here, zinc is dissolved from the scrap in hot caustic and is recovered electrolytically as dendritic powder. The dezinced ferrous scrap is rinsed and used directly. The process is effective for zinc, lead, and aluminum removal on loose and baled scrap and on all types of galvanized steel. Pilot testing has been conducted in Hamilton, Ontario for batch treatment of 900 tonnes of mostly baled scrap. A pilot plant in East Chicago, Indiana, now in its second generation, has dezinced in a continuous process mode about 1,800 tonnes of loose clips and shredded stamping plant scrap; this scrap typically has residual zinc below 0.05% and sodium dragout below 0.001%. This paper reviews caustic dezincing pilot plant performance and economics