Hadron Spectroscopy with COMPASS at CERN

The aim of the COMPASS hadron programme is to study the light-quark hadron spectrum, and in particular, to search for evidence of hybrids and glueballs. COMPASS is a fixed-target experiment at the CERN SPS and features a two-stage spectrometer with high momentum resolution, large acceptance, particle identification and calorimetry. A short pilot run in 2004 resulted in the observation of a spin-exotic state with $J^{PC} = 1^{-+}$ consistent with the debated $\pi1(1600)$. In addition, Coulomb production at low momentum transfer data provide a test of Chiral Perturbation Theory. During 2008 and 2009, a world leading data set was collected with hadron beam which is currently being analysed. The large statistics allows for a thorough decomposition of the data into partial waves. The COMPASS hadron data span over a broad range of channels and shed light on several different aspects of QCD.Comment: 4 pages, 5 figure

Checklist of the Ants of Michigan (Hymenoptera: Formicidae)

A total of 113 species of ants is recorded by county from the state of Michigan. The list is based upon literature records and specimens in the authors\u27 collections and those of the University of Michigan Museum of Zoology and the Michigan State University Department of Entomology. The list includes 3 species in Ponerinae, 44 in Myrnucinae, 6 in Dolichoderinae, and 60 in Formicinae. Ten species represent new state records. Five distribution pat- terns are evident: statewide (39 species), southern counties only (5), southern 3/4th of Lower Peninsula (10), Lower Peninsula (17), and Upper Peninsula (2). Forty species have been collected too infrequently to determine the distribution within the state

Quantum Correction to Conductivity Close to Ferromagnetic Quantum Critical Point in Two Dimensions

We study the temperature dependence of the conductivity due to quantum interference processes for a two-dimensional disordered itinerant electron system close to a ferromagnetic quantum critical point. Near the quantum critical point, the cross-over between diffusive and ballistic regimes of quantum interference effects occurs at a temperature $T^{\ast}=1/\tau \gamma (E_{F}\tau)^{2}$, where $\gamma$ is the parameter associated with the Landau damping of the spin fluctuations, $\tau$ is the impurity scattering time, and $E_{F}$ is the Fermi energy. For a generic choice of parameters, $T^{\ast}$ is smaller than the nominal crossover scale $1/\tau$. In the ballistic quantum critical regime, the conductivity behaves as $T^{1/3}$.Comment: 5 pages, 1 figur

Inefficiency and productivity growth in banking: a comparison of stochastic econometric and thick frontier methods

A comparison of alternative methods for estimating inefficiency and productivity growth in banking, showing that inefficiencies are sufficiently large to dominate scale economies and that measured technological progress has been small, or even negative, as a result of institutional events that occurred during 1977-88.Banks and banking - Costs ; Production (Economic theory)

Quantum and Fisher Information from the Husimi and Related Distributions

The two principal/immediate influences -- which we seek to interrelate here -- upon the undertaking of this study are papers of Zyczkowski and Slomczy\'nski (J. Phys. A 34, 6689 [2001]) and of Petz and Sudar (J. Math. Phys. 37, 2262 [1996]). In the former work, a metric (the Monge one, specifically) over generalized Husimi distributions was employed to define a distance between two arbitrary density matrices. In the Petz-Sudar work (completing a program of Chentsov), the quantum analogue of the (classically unique) Fisher information (montone) metric of a probability simplex was extended to define an uncountable infinitude of Riemannian (also monotone) metrics on the set of positive definite density matrices. We pose here the questions of what is the specific/unique Fisher information metric for the (classically-defined) Husimi distributions and how does it relate to the infinitude of (quantum) metrics over the density matrices of Petz and Sudar? We find a highly proximate (small relative entropy) relationship between the probability distribution (the quantum Jeffreys' prior) that yields quantum universal data compression, and that which (following Clarke and Barron) gives its classical counterpart. We also investigate the Fisher information metrics corresponding to the escort Husimi, positive-P and certain Gaussian probability distributions, as well as, in some sense, the discrete Wigner pseudoprobability. The comparative noninformativity of prior probability distributions -- recently studied by Srednicki (Phys. Rev. A 71, 052107 [2005]) -- formed by normalizing the volume elements of the various information metrics, is also discussed in our context.Comment: 27 pages, 10 figures, slight revisions, to appear in J. Math. Phy

Planar laser-induced fluorescence imaging of OH in the exhaust of a bi-propellant thruster

Planar laser-induced fluorescence imaging of the hydroxyl radical has been performed on the flow produced by the exhaust of a subscale H2/O2 fueled bi-propellant rocket engine. Measurements were made to test the feasibility of OH (0,0) and (3,0) excitation strategies by using injection seeded XeCl and KrF excimer lasers, respectively. The flow is produced with hydrogen and oxygen reacting at a combustor chamber pressure of 5 atm which then exhausts to the ambient. The hydroxyl concentration in the exhaust flow is approximately 8 percent. Fluorescence images obtained by pumping the Q1(3) transition in the (0,0) band exhibited very high signals but also showed the effect of laser beam absorption. To obtain images when pumping the P1(8) transition in the (3,0) band it was necessary to use exceptionally fast imaging optics and unacceptably high intensifier gains. The result was single-shot images which displayed a signal-to-noise ratio of order unity or less when measured on a per pixel basis

Imaging through turbulence with a quadrature-phase optical interferometer

We present an improved technique for imaging through turbulence at visible wavelengths using a rotation shearing pupil-plane interferometer, intended for astronomical and terrestrial imaging applications. While previous astronomical rotation shearing interferometers have made only visibility modulus measurements, this interferometer makes four simultaneous measurements on each interferometric baseline, with phase differences of π/2 between each measurement, allowing complex visibility measurements (modulus and phase) across the entire input pupil in a single exposure. This technique offers excellent wavefront resolution, allowing operation at visible wavelengths on large apertures, is potentially immune to amplitude fluctuations (scintillation), and may offer superior calibration capabilities to other imaging techniques. The interferometer has been tested in the laboratory under weakly aberrating conditions and at Palomar Observatory under ordinary astronomical observing conditions. This research is based partly on observations obtained at the Hale Telescope

Physical properties of SrSn4 single crystals

We present detailed thermodynamic and transport measurements on single crystals of the recently discovered binary intermetallic superconductor, SrSn4. We find this material to be a slightly anisotropic three-dimensional, strongly-coupled, possibly multi-band, superconductor. Hydrostatic pressure causes a decrease in the superconducting transition temperature at the rate of -0.068 K/kbar. Band structure calculations are consistent with experimental data on Sommerfeld coefficient and upper superconducting critical field anisotropy and suggest complex, multi-sheet Fermi surface formed by four bands.Comment: Figure 11 correcte

PU(2) monopoles and a conjecture of Marino, Moore, and Peradze

In this article we show that some of the recent results of Marino, Moore, and Peradze (math.DG/9812042, hep-th/9812055) -- in particular their conjecture that all closed, smooth four-manifolds with b_2^+ > 1 (and Seiberg-Witten simple type) are of `superconformal simple type' -- can be understood using a simple mathematical argument via the PU(2)-monopole cobordism of Pidstrigach and Tyurin (dg-ga/9507004) and results of the first and third authors (dg-ga/9712005, dg-ga/9709022).Comment: 13 pages, 1 figure. Improved exposition, typographical slips corrected, figure and references added. Minor correction on page 2. To appear in Mathematical Research Letter

Pretvorba elektromagnetskog vala u elektronsko-zvučni val u nehomogenoj plazmi

The transverse electromagnetic waves and the longitudinal electron-acoustic waves are coupled to each other by the gradients of density or temperature in a plasma. There are also other coupling factors, such as the static magnetic field or nonlinearities existing in the medium. Due to coupling of waves, excitation of one leads to the generation of the other. This results in mutual transfer of power. In the present paper, the expression for the energy flux of acoustic wave due to conversion of electromagnetic wave passing through an inhomogeneous plasma has been obtained using the W. K. B. method. It is suggested that expansion of ionized shell of hot stars and mass loss would be possibly due to the energy conversion process.Poprečni elektromagnetski valovi i uzdužni elektronsko-zvučni valovi vezani su međusobno gradijentima gustoće i temperature u plazmi. Djeluju i drugi vezni čimbenici, kao statičko magnetsko polje ili nelinearnost plazme. Zbog povezivanja valova, uzbuda jednih stvara druge. Stoga imamo uzajamni prijenos energije. U ovom se radu, primjenom W. K. B. metode, izvodi izraz za tok energije zvučnog vala zbog pretvorbe elektromagnetskog vala koji prolazi nehomogenom plazmom. Izražava se mogućnost da su širenje ionizirane ljuske vrućih zvijezda i gubitak mase posljedica procesa pretvorbe energije