CERN Document Server

This Resource Letter provides a guide to the literature on Quantum Chromodynamics (QCD), the relativistic quantum field theory of the strong interactions. Journal articles, books, and other documents are cited for the following topics: quarks and color, the parton model, Yang-Mills theory, experimental evidence for color, QCD as a color gauge theory, asymptotic freedom, QCD for heavy hadrons, QCD on the lattice, the QCD vacuum, pictures of quark confinement, early and modern applications of perturbative QCD, the determination of the strong coupling and quark masses, QCD and the hadron spectrum, hadron decays, the quark-gluon plasma, the strong nuclear interaction, and QCD's role in nuclear physics. The letter {E} after an item indicates elementary level or material of general interest to persons ...

Energy Technology Data Exchange (ETDEWEB)

A survey is given on the present status of the nucleon parton distributions and related precision calculations and precision measurements of the strong coupling constant {alpha}{sub s}(M{sup 2}{sub Z}). We also discuss the impact of these quantities on precision observables at hadron colliders. (orig.)

CERN Document Server

We compute QCD corrections to the production of a ttbar pair in association with a hard photon at the Tevatron and the LHC. This process allows a direct measurement of the top quark electromagnetic couplings that, at the moment, are only loosely constrained. We include top quark decays, treating them in the narrow width approximation, and retain spin correlations of final-state particles. Photon radiation off top quark decay products is included in our calculation and yields a significant contribution to the cross-section. We study next-to-leading order QCD corrections to the ppbar -> ttbar+gamma process at the Tevatron for the selection criteria used in a recent measurement by the CDF collaboration. We also discuss the impact of QCD corrections to the pp -> ttbar+gamma process on the measurement of the top quark electric charge at the 14 TeV LHC.

CERN Document Server

The use of a running coupling constant in renormalizable theories is well known, but the implementation of this idea for effective field theories with a dimensional coupling constant is in general less useful. Nevertheless there are multiple attempts to define running couplings including the effects of gravity, with varying conclusions. We sort through many of the issues involved, most particularly the idea of operator mixing and also the kinematics of crossing, using calculations in Yukawa and lambda phi^4 theory as illustrative examples. We remain in the perturbative regime. In some theories with a high permutation symmetry, such as lambda phi^4, a reasonable running coupling can be defined. However in most cases, such as Yukawa and gauge theories, a running coupling fails to correctly account for ...

International Nuclear Information System (INIS)

The research of the CELLO collaboration is reviewed. After a description of the CELLO detector tests of QCD and hadronic final states by determination of the strong coupling constant and studies of inclusive production of electrons and muons in multihadronic events in e"+e"- annihilation are described. Then studies of deep inelastic e#gamma# scattering with lepton pair production and the study of the structure function of the photon are briefly described. Finally studies on QED processes are described together with tau decays. (HSI).

Energy Technology Data Exchange (ETDEWEB)

This report presents the operating results for Run 255 at the Advanced Coal Liquefaction Research and Development Facility in Wilsonville, Alabama. This run operated in the Close Coupled Integrated Two-Stage Liquefaction mode (CC-ITSL) using Martin Lake Texas lignite. The purpose of this run was to demonstrate unit and system operability with Martin Lake lignite. Run 255 began on 20 March 1988 and continued through 9 June 1988. During this period, 204.4 MF tons of Martin Lake Texas lignite were fed in 1865.5 hours of operation. 70 figs., 21 tabs.

CERN Document Server

A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving aside exotic spectroscopy, which has been the subject of other publications, in this note I call attention on two recent applications. One is that the running quark mass in the mid-infrared can be probed from excited baryons thanks to parity doubling, a consequence of insensitivity to chiral symmetry breaking. Fast quarks are asymptotically free and behave as massless, so hadrons containing fast quarks decouple from the condensate. Their (power-law) rate of decoupling reflects on the rate of decreasing parity splittings, which can be measured. The second is that, in analogy with the Franck-Condon principle of molecular physics, the velocity distribution of the heavy quarks inside a heavy hadron can be mapped out ...

Science.gov (United States)

This report presents the results of Run 261 performed at the Advanced Coal Liquefaction R & D Facility in Wilsonville, Alabama. The run started on January 12, 1991 and continued until May 31, 1991, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Illinois No. 6 seam bituminous coal (from Burning star No. 2 mine). In the first part of Run 261, a new bimodal catalyst, EXP-AO-60, was tested for its performance and attrition characteristics in the catalytic/catalytic mode of the CC-ITSL process. The main objective of this part of the run was to obtain good process performance in the low/high temperature mode of operation along with well-defined distillation product end boiling points. In the second part of Run 261, Criterion (Shell) 324 catalyst was tested. The objective of this test was to evaluate the operational stability and ...

Energy Technology Data Exchange (ETDEWEB)

This patent describes a display unit of a speedometer for an automobile, comprising: a constant speed running circuit capable of producing output signals indicative of a desired car speed; an actual car speed operational circuit capable of producing output signals indicative of actual car speed; a comparing circuit for comparing the amplitudes of the output signals of the constant speed running operational circuit and the actual car speed operational circuit; bar graph decoders receiving the output signals from the constant speed running operational circuit and the actual car speed operational circuit; an EX-OR circuit having inputs coupled to respective bar graph decoders and having an output; and OR circuit having inputs coupled to respective bar graph decoders and having an output; selector means coupled to the output of the EX-OR circuit and the output of ...

CERN Document Server

We make a comparison of the predicted effective weak mixing angle, the Z-on resonance asymmetries and the W-boson mass to the LEP and SLD data at their present status. We find that the predicted MSSM values for the effective weak mixing angle are in agreement with the LEP+SLD average value for a ``heavy'' SUSY breaking scale while we observe an agreement with SLD data in the case of a ``light'' SUSY breaking scale. The resulting values for the W-boson mass and for the electron left-right asymmetries are compatible with CDF,UA2,DO and LEP data respectively. Unexpectedly we find that the supersymmetric QCD contributions to the Z-observables tend to vanish everywhere in the M1/2-M0 plane. Furthermore, values of M1/2 which are greater than 500 GeV are favoured by the MSSM if one considers the current experimental value for the strong coupling.

CERN Document Server

We study the high energy behaviour of Yang-Mills theory under the inclusion of gravity. In the weak-gravity limit, the running gauge coupling receives no contribution from the gravitational sector, if all symmetries are preserved. This holds true with and without cosmological constant. We also show that asymptotic freedom persists in general field-theory-based gravity scenarios including gravitational shielding as well as asymptotically safe gravity.

Science.gov (United States)

TART97 is a coupled neutron-photon, 3 dimensional, combinatorial geometry, time dependent Monte Carlo transport code. This code can run on any modern computer. It is a complete system to assist you with input preparation, running Monte Carlo calculations, and analysis of output results. TART97 is also incredibly fast: if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART 97 is distributed on CD. This CD contains on-line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART97 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART97 and ist data files.

CERN Document Server

In this article, we investigate the "naive non-abelianization" (NNA) contributions of the higher-twist Feynman diagrams to the large-$p_T$ inclusive pion production cross section in proton-proton collisions and present the general formulae for the higher-twist differential cross sections in the case of the running coupling and frozen coupling approaches. We compared the resummed "naive non-abelianization" higher-twist cross sections with the ones obtained in the framework of the frozen coupling approach and leading-twist cross section. The structure of infrared renormalon singularities of the higher twist subprocess cross section and it's resummed expression (the Borel sum) are found. It is shown that the resummed result depends on the choice of the meson wave functions used in the calculations. We discuss the phenomenological consequences of possible higher-twist contributions to the meson production ...

Energy Technology Data Exchange (ETDEWEB)

This thesis describes the analysis of the semileptonic decay D{sup 0} {yields} {bar K}{sup 0} {pi}{sup -} {mu}{sup +}{nu} using FOCUS data. FOCUS is a fixed target experiment at Fermilab that studies the physics of the charm quark. Particles containing charm are produced by photon-gluon fusion from the collision of a photon beam on a BeO target. The experiment is characterized by excellent vertex resolution and particle identification. The spectrometer consists of three systems for track reconstruction (two silicon systems and one multiwire proportional chamber system) and two magnets of opposite polarity. The polarity of the magnet is such that the events of e{sup +}e{sup -} pairs produced in the target (which constitutes the main background) travel through a central opening in the detectors without interactions. Particle momentum is measured from the deflection angle in the magnets. Three multicell Cerenkov counters are used for charged particle identification (for e, {pi}, K, and ...

Energy Technology Data Exchange (ETDEWEB)

We find that tachyonic orbifold examples of AdS/CFT have corresponding instabilities at small radius, and can decay to more generic gauge theories. We do this by computing a destabilizing Coleman-Weinberg effective potential for twisted operators of the corresponding quiver gauge theories, generalizing calculations of Tseytlin and Zarembo, and interpreting them in terms of the large-N behavior of twisted-sector modes. The dynamically generated potential involves double-trace operators, which affect large-N correlators involving twisted fields but not those involving only untwisted fields, in line with large-N inheritance arguments. We point out a simple reason that no such small radius instability exists in gauge theories arising from freely acting orbifolds, which are tachyon free at large radius. When an instability is present, twisted gauge theory operators with the quantum numbers of the large-radius tachyons aquire vacuum expectation values, leaving a gauge theory with fewer ...

CERN Document Server

We present a model of inflation in a supergravity framework in the Einstein frame where the Higgs field of the next to minimal supersymmetric standard model (NMSSM) plays the role of the inflaton. Previous attempts which assumed non-minimal coupling to gravity failed due to a tachyonic instability of the singlet field during inflation. A canonical K\\"{a}hler potential with \\textit{minimal coupling} to gravity can resolve the tachyonic instability but runs into the $\\eta$-problem. We suggest a model which is free of the $\\eta$-problem due to an additional coupling in the K\\"{a}hler potential which is allowed by the Standard Model gauge group. This induces directions in the potential which we call K-flat. For a certain value of the new coupling in the (N)MSSM, the K\\"{a}hler potential is special, because it can be associated with a certain shift symmetry for the Higgs doublets, ...

CERN Document Server

Assuming the hoop conjecture in classical general relativity and quantum mechanics, any observer who attempts to perform an experiment in an arbitrarily small region will be stymied by the formation of a black hole within the spatial domain of the experiment. This behavior is often invoked in arguments for a fundamental minimum length. Extending a proof of the hoop conjecture for spherical symmetry to include higher curvature terms we investigate this minimum length argument when the gravitational couplings run with energy in the manner predicted by asymptotically safe gravity. We show that argument for the mandatory formation of a black hole within the domain of an experiment fails. Neither is there a proof that a black hole doesn't form. Instead, whether or not an observer can perform measurements in arbitrarily small regions depends on the specific numerical values of the couplings near the UV fixed point. We further ...

Energy Technology Data Exchange (ETDEWEB)

An advanced process for the separation of hydrogen sulfide (H{sub 2}S) from coal gasification product streams through an electrochemical membrane is being developed. H{sub 2}S is removed from the syn-gas stream, split into hydrogen, which enriches the exiting syn-gas, and sulfur, which is condensed from an inert sweep gas stream. The process allows removal of H{sub 2}S without cooling the gas stream and with negligible pressure loss through the separator. The process is made economically attractive by the lack of need for a Claus process for sulfur recovery. Membrane manufacturing coupled with full-cell experimentation was the primary focus this quarter. A tape-casted zirconia membrane was developed and utilized in one full-cell experiment (run 25); run 24 utilized a fabricated membrane purchased from Zircar Corporation. Results are discussed.

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: study of Z{sup 0} decays; QCD; new particles; Higgs bosons; and forward hadron calorimeter system.

British Library Electronic Table of Contents (United Kingdom)

Ground thermal energy storage is a means of storing thermal energy underground during the summer and utilizing it during the winter. The main use of such a technology is in the heating, ventilating and air conditioning sector where the ground provides a stable temperature reservoir for a heat pump system. Heat pumps are mechanical systems that provide heating to a space in the winter, and cooling in the summer. They are increasingly popular because the same system provides both heating modes, depending on the direction of the cycle upon which they operate. The stable temperature reservoir allows the heat pump system to run at a higher efficiency. Thermal energy is transmitted to and from the ground by circulation of water through standing column geothermal wells. In commercial applications...

CERN Document Server

We study general two-dimensional sigma-models which do not possess manifest Lorentz invariance. We show how demanding that Lorentz invariance is recovered as an emergent on-shell symmetry constrains these sigma-models. The resulting actions have an underlying group-theoretic structure and resemble Poisson--Lie T-duality invariant actions. We consider the one-loop renormalization of these models and show that the quantum Lorentz anomaly is absent. We calculate the running of the couplings in general and show, with certain non-trivial examples, that this agrees with that of the T-dual models obtained classically from the duality invariant action. Hence, in these cases solving constraints before and after quantization are commuting operations.

International Nuclear Information System (INIS)

We review two types of D-brane processes where open strings are created. In the first type, a closed string incident on a collection of D-branes is converted into a number of open strings running along them. For the case of threebranes we compare the leading absorption rate with that in semiclassical gravity, and find exact agreement. A supersymmetric non-renormalization theorem guarantees that this agreement survives all corrections in powers of the string coupling times the number of branes. The second type of process is creation of stretched open strings by crossing D-branes. We show that this is possible whenever a p-brane passes through an (8-p)-brane positioned orthogonally to it. The extra attractive force exerted by the stretched open string is crucial for finding that the net force cancels in this BPS system. (orig.)

CERN Document Server

We study the phenomenological consequences of a four site Higgsless model based on the SU(2)_L x SU(2)_1 x SU(2)_2 x U(1)_Y gauge symmetry, which predicts two neutral and four charged extra gauge bosons, Z_{1,2} and W_{1,2}. The model represents an extension of the minimal three site version (or BESS model), largely investigated in the literature, which includes three heavy vector bosons. We compute the properties of the new particles, and derive indirect and direct limits on their masses and couplings from LEP and Tevatron data and from the perturbative unitarity requirements. In contrast to other Higgsless models characterized by fermiophobic extra gauge bosons, here sizeable fermion-boson couplings are allowed by the electroweak precision data. The prospects of detecting the new predicted particles in the favoured Drell-Yan channel at the LHC are thus investigated. The outcome is that all six extra gauge bosons could be discovered in the ...

Science.gov (United States)

The Simplified Boiling Water Reactor (SBWR) designed by General Electric is a natural circulation reactor with enhanced safety features for potential accidents. It has a strong coupling between power and flow in the reactor core, hence the neutronic coupling with thermal-hydraulics is specially important. The potential geysering instability during the early part of a SBWR startup at low flow, low power and low pressure is of particular concern. The RAMONA-4B computer code developed at Brookhaven National Laboratory (BNL) for the SBWR has been used to simulate a SBWR startup transient and evaluate its stability, using a simplified four-channel representation of the reactor core for the thermal-hydraulics. This transient was run for 20,000 sec (5.56 hrs) in order to cover the essential aspect of the SBWR startup. The simulation showed that the SBWR startup was a very challenging event to analyze as it required accurate ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents an approach to comparing computer run time of building simulation programs. The computing run time of a simulation program depends on several key factors, including the calculation algorithm and modeling capabilities of the program, the run period, the simulation time step, the complexity of the energy models, the run control settings, and the software and hardware configurations of the computer that is used to make the simulation runs. To demonstrate the approach, simulation runs are performed for several representative DOE-2.1E and EnergyPlus energy models. The computer run time of these energy models are then compared and analyzed.

Energy Technology Data Exchange (ETDEWEB)

After reviewing some of the mathematical foundations and numerical difficulties facing lattice QCD, I review the status of several calculations relevant to experimental high-energy physics. The topics considered are moments of structure functions, which may prove relevant to search for new phenomena at the LHC, and several aspects of flavor physics, which are relevant to understanding CP and flavor violation.

Energy Technology Data Exchange (ETDEWEB)

I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.

International Nuclear Information System (INIS)

I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.

Energy Technology Data Exchange (ETDEWEB)

I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.

CERN Document Server

We calculate the light `glueball' mass spectrum in N_f=2 lattice QCD using a fermion action that is non--perturbatively O(a) improved. We work at lattice spacings a~0.1 fm and with quark masses that range down to about half the strange quark mass. We find the statistical errors to be moderate and under control on relatively small ensembles. We compare our mass spectrum to that of quenched QCD at the same value of a. Whilst the tensor mass is the same (within errors), the scalar mass is significantly lighter in the dynamical lattice theory, by a factor of ~0.84 +/- 0.03. We discuss what the observed m_q dependence of this suppression tells us about the dynamics of glueballs in QCD. We also calculate the masses of flux tubes that wind around the spatial torus, and extract the string tension from these. As we decrease the quark mass we see a small but growing vacuum expectation value for the corresponding flux tube operators. ...

Energy Technology Data Exchange (ETDEWEB)

The microbial transport simulator (MTS) is a three-dimensional, three-phase, multiple-component numerical model that permits the study of the transport of microorganisms and nutrients in porous media. Microbial parameters incorporated into MTS include: Microbial growth and decay, microbial deposition, chemotaxis, diffusion, convective dispersion, tumbling, and nutrient consumption. Governing equations for microbial and nutrient transport are coupled with continuity and flow equations under conditions appropriate for a black oil reservoir. The model`s mathematical formulations and preparation procedures of data files for conducting simulations using MTS are described. A general background of microbial transport simulation is given in Section I and the governing equations, mechanisms, and numerical solutions of MTS are given in Section II. Explanations for preparing an input data file with reservoir and microbial transport data are described in Section III, and ...

CERN Document Server

We present here the effective theory of inflation `a la Ginsburg-Landau in which the inflaton potential is a polynomial. The slow-roll expansion becomes a systematic 1/N expansion where N ~ 60. The spectral index and the ratio of tensor/scalar fluctuations are n_s - 1 = O(1/N), r = O(1/N) while the running turns to be d n_s/d \\ln k = O(1/N^2) and can be neglected. The energy scale of inflation M ~ 0.7 10^{16} GeV is completely determined by the amplitude of the scalar adiabatic fluctuations. A complete analytic study plus the Monte Carlo Markov Chains (MCMC) analysis of the available CMB+LSS data showed: (a) the spontaneous breaking of the phi -> - phi symmetry of the inflaton potential. (b) a lower bound for r: r > 0.023 (95% CL) and r > 0.046 (68% CL). (c) The preferred inflation potential is a double well, even function of the field with a moderate quartic coupling yielding as most probable values: n_s = 0.964, r = 0.051. This ...

CERN Document Server

Both Grand Unified symmetries and discrete flavour symmetries are appealing ways to describe apparent structures in the gauge and flavour sectors of the Standard Model. Both symmetries put constraints on the high energy behaviour of the theory. This can give rise to unexpected interplay when building models that possess both symmetries. We investigate on the possibility to combine a Pati-Salam model with the discrete flavour symmetry S4 that gives rise to quark-lepton complementarity. Under appropriate assumptions at the GUT scale, the model reproduces fermion masses and mixings both in the quark and in the lepton sectors (the Beauty). We show that in particular the Higgs sector and the running Yukawa couplings are strongly affected by the combined constraints of the Grand Unified and family symmetries (the Beast). This in turn reduces the phenomenologically viable parameter space. In the allowed regions, we can reproduce the quark masses and ...

Energy Technology Data Exchange (ETDEWEB)

Operating the Stanford Linear Collider (SLC) at 120Hz repetition rate requires the presence of two bunches in both the electron and the positron damping ring. The {pi}-mode instability, a coupled bunch instability where the two bunches oscillate with a phase difference of 180{degrees}, had been observed in both rings with low current thresholds of 7{sup *}10{sup 9} particles per bunch. To avoid the instability, the RF system had to be operated in ways which in general reduced the cavity gap voltages and required constant operational attention. For the 1992 running cycle a passive cavity was installed and successfully tested. It is tuned to the frequency of the lower synchrotron oscillation sideband of an odd revolution harmonic. The impedance of the cavity then damps {pi}-mode oscillations very similar to the Robinson damping provided by the main RF cavities which damps O-mode synchrotron oscillations. In this report we describe the motivation ...

Energy Technology Data Exchange (ETDEWEB)

At future [gamma][gamma] colliders copious production of [ital t] [bar t] pairs is possible. This would allow for a detailed investigation of the interactions involving the top quark. We propose some correlations which are sensitive to [ital t] [bar t] final state interactions and we compute the QCD and standard model Higgs boson contributions to these correlations. A correlation resulting from the QCD induced transverse polarization of top quarks is found to be sizable and measurable at a high energy [ital e][sup +][ital e][sup [minus

International Nuclear Information System (INIS)

At future #gamma##gamma# colliders copious production of t bar t pairs is possible. This would allow for a detailed investigation of the interactions involving the top quark. We propose some correlations which are sensitive to t bar t final state interactions and we compute the QCD and standard model Higgs boson contributions to these correlations. A correlation resulting from the QCD induced transverse polarization of top quarks is found to be sizable and measurable at a high energy e"+e"- collider, which is operated as a photon collider through backscattering of laser photons, at an integrated luminosity of 10 fb"-"1.

Energy Technology Data Exchange (ETDEWEB)

The curves that describe the M-theoretic extension of type IIA string configurations with non-supersymmetric field theories on their surface exhibit a duality map. The map suggests a continued link between an SU(N) gauge theory with F flavors and an SU(F{minus}N) gauge theory with F flavors (the duality of supersymmetric QCD) even when the gaugino mass is taken to infinity. Within the context of the field theory such a duality only continues to make sense if the scalar fields remain light. We discuss the difficulties of decoupling the scalars within this framework. thinsp {copyright} {ital 1998} {ital The American Physical Society}

Energy Technology Data Exchange (ETDEWEB)

Based on QCD conformal partial wave expansion to leading order conformal spin accuracy, we present the light-cone distribution amplitudes (DAs) of {sigma} and {lambda} baryons up to twist 6. It is concluded that fourteen independent DAs are needed to describe the valence three-quark states of the baryons at small transverse separations. The nonperturbative parameters relevant to the DAs are determined within the framework of QCD sum rule method. With the obtained DAs, a simple investigation on the electromagnetic form factors of these baryons are given. The magnetic moments of the baryons are estimated by fitting the magnetic form factor with the dipole formula.

Energy Technology Data Exchange (ETDEWEB)

The goal of this DOE Vision-21 project work scope is to develop an integrated suite of software tools that can be used to simulate and visualize advanced plant concepts. Existing process simulation software does not meet the DOE's objective of ''virtual simulation'' which is needed to evaluate complex cycles. The overall intent of the DOE is to improve predictive tools for cycle analysis, and to improve the component models that are used in turn to simulate the cycle. Advanced component models are available; however, a generic coupling capability that will link the advanced component models to the cycle simulation software remains to be developed. In the current project, the coupling of the cycle analysis and cycle component simulation software will be based on an existing suite of programs. The challenge is to develop a general-purpose software and communications link between the cycle analysis ...

Energy Technology Data Exchange (ETDEWEB)

The title of the workshop, ''The QCD Phase Transitions'', in fact happened to be too narrow for its real contents. It would be more accurate to say that it was devoted to different phases of QCD and QCD-related gauge theories, with strong emphasis on discussion of the underlying non-perturbative mechanisms which manifest themselves as all those phases. Before we go to specifics, let us emphasize one important aspect of the present status of non-perturbative Quantum Field Theory in general. It remains true that its studies do not get attention proportional to the intellectual challenge they deserve, and that the theorists working on it remain very fragmented. The efforts to create Theory of Everything including Quantum Gravity have attracted the lion share of attention and young talent. Nevertheless, in the last few years there was also a tremendous progress and even some shift of ...

Energy Technology Data Exchange (ETDEWEB)

New measurements of the spin structure functions of the proton and deuteron g{sub 1}{sup p}(x, Q{sup 2}) and g{sub 1}{sup d}(x, Q{sup 2}) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W < 2 GeV), the data and QCD fits are in good agreement in both magnitude and Q{sup 2} dependence for Q{sup 2} > 1.7 GeV{sup 2}/c{sup 2}. This ''global'' duality appears to result from cancellations among the prominent ''local'' resonance regions: in particular strong {sigma}{sub 3/2} contributions in the {Delta}(1232) region appear to be compensated by strong {sigma}{sub 1/2} contributions in the resonance region centered on 1.5 GeV. These results are encouraging for the extension of NLO QCD fits to lower W and Q{sup 2} ...

Energy Technology Data Exchange (ETDEWEB)

We point out that the occurrence of a large-distance ''Coulomb'' term in the static quark-antiquark potential is related to tachyons in the underlying string model. Thus, the tachyon contents determine the coefficient of the ''Coulomb'' term. For a scalar string, one has Luescher's result -(d-2) /24R, for a Neveu-Schwarz string one obtains -(d-2) /16R, whereas for the Ramond string (and strings without tachyons) the ''Coulomb'' term vanishes. Monte Carlo data for QCD prefers a ''Coulomb'' term. This is not inconsistent with the tachyonic origin of this term, since the large-distance behaviour of string models is consistent even with tachyons. Also, critical dimensions are not necessary at large distances.

Energy Technology Data Exchange (ETDEWEB)

We present production rates of the two- and three-jet final states for the processes of massive cc/bb quark production in circularly polarized photon-photon collisions, including QCD radiative corrections. Lowest-order cross section, one-loop virtual correction, and gluon emission correction are shown to be of the same order of magnitude for bb quark production at s{sub {gamma}{gamma}} similar 100 GeV. It is shown that the signal from an intermediate mass Higgs boson is observable at a photon-photon collider, though the statistical significance is substantially reduced with respect to the tree-level calculation. ((orig.)).

CERN Document Server

In QCD the spontaneous breaking of chiral symmetry and the U(1) axial anomaly can be understood considering instantons as the gauge configurations mediating quark-quark interaction. The existence of an exact zero mode solution of the Dirac equation in the field of a single instanton is the fundamental ingredient of this analysis. Explicit expressions for psi_0 are available for T different from 0 and mu=0, and mu different from 0 and T=0. In this paper we derive the solution for the most general case T different from 0 and mu different from 0. This new result opens the possibility of investigating the QCD dynamics associated with instantons in the full phase diagram. As a first step in this direction we will study the dependence of the instanton density from the thermodynamic coordinates.

CERN Document Server

The main topic of this thesis concerns efficient algorithms for the calculation of determinants of the kind of matrix typically encountered in lattice QCD. In particular an efficient method for calculating the fermion determinant is described. Such a calculation is useful to illustrate the effects of light dynamical (virtual) quarks. The methods employed in this thesis are stochastic methods, based on the Lanczos algorithm, which is used for the solution of large, sparse matrix problems via a partial tridiagonalisation of the matrix. Here an implementation is explored which requires less exhaustive treatment of the matrix than previous Lanczos methods. This technique exploits the analogy between the Lanczos tridiagonalisation algorithm and Gaussian quadrature in order to calculate the fermion determinant. A technique for determining a number of the eigenvalues of the matrix is also presented. A demonstration is then given of how one can improve upon this estimate ...

Energy Technology Data Exchange (ETDEWEB)

A classic sum rule by Das et al. is extended to seven of the low-energy constant K{sub i}, introduced by Urech, which parameterizes electromagnetic corrections at chiral order O(e{sup 2}p{sup 2}). Using the spurion formalism, a simple convolution representation is shown to hold and the structure in terms of the chiral renormalization scale, QCD renormalization scale and the QED gauge parameter is displayed. The role of the resonances is studied as providing rational interpolants to relevant QCD n-point functions in the Euclidean domain. A variety of asymptotic constraints must be implemented which have phenomenological consequences. A current assumption concerning the dominance of the lowest-lying resonances is shown clearly to fail in some cases. (author)

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

The extensive research and development effort was initiated by the U.S. Department of Energy (DOE) in 2002 at West Virginia University (WVU) in order to investigate practical ways of reducing the structural weight and increasing the durability of heavy vehicles through the judicious use of lightweight composite materials. While this project was initially focused on specific Metal Matrix Composite (MMC) material, namely Aluminum/Silicon Carbide (Al/SiC) commercially referenced as ''LANXIDE'', the current research effort was expanded from the component level to the system level and from MMC to other composite material systems. Broadening the scope of this research is warranted not only by the structural and economical deficiencies of the ''LANXIDE'' MMC material, but also by the strong coupling that exists between the material and the geometric characteristics of the structure. Such ...

Energy Technology Data Exchange (ETDEWEB)

The running data of the super energy saving car on a course with a little difference within 1m in elevation were reported which was developed to pursue the minimum fuel consumption. The super car was featured by length of 2.72m, vehicle running mass of 38.5kg, engine displacement of 42cc and a rear drive tricycle with 2(F) and 1(R). The super car turned 10 times on a racing circuit of 925m a round at 20km/h or more in average speed, repeating engine-driven running and engine-stopped coasting. As a result, the vehicle velocity distribution was slightly affected by tire revolution, while the accelerating resistance was strongly affected by that. With an increase in tire revolution, the maximum accelerating resistance decreased in driven running and its variation converged rapidly in coasting. A total of distance in driven running was only 8% of the whole running ...

UK PubMed Central (United Kingdom)

1. The relation of V̇_O2 and speed was measured on seven athletes running on a cinder track and an all-weather track. The results were compared...Full Text Available

Science.gov (United States)

Information Technology Glossary of Terms. Applets: Programs that run inside net browsers, usually in Java and typically involving modestly interactive ...

Science.gov (United States)

... Hydropower analysis may include run-of-river, peaking, and pumped storage plants as well as system power operation. ...

Energy Technology Data Exchange (ETDEWEB)

A polarized proton physics run took place during January, 1988, at the Brookhaven AGS. It is the purpose of this paper to review the tune-up period preceding that run. This was the third such run at the AGS; the others occurred in June of 1984 and February of 1986. Some comparisons will be drawn among these. A thorough review of the history and hardware associated with the acceleration of polarized protons at the AGS can be found in the proceedings of the last meeting of this group at Protvino and will not be repeated here. 2 refs., 6 figs., 1 tab.

CERN Document Server

The early idea that a non-perturbative gluon condensate affects the spectrum of heavy quarks is revisited in the light of modern simulation techniques. We evaluate the low lying spectrum of bound states of two heavy quarks for large hypothetical quark mass, m_Q > m_b, using non-relativistic QCD and compare with other models to test the consistency.

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Stable strange quark matter produced in the QCD phase transition in the early universe will trap neutrons and repel protons, thus reducing primordial helium production, Ysub(p). For reasonable values of Ysub(p), the radius of strange droplets must exceed 10/sup 6/ cm if strange matter shall solve the dark-matter problem without spoiling Big Bang helium synthesis. (orig.).

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Quark-hadron duality addresses some of the most fundamental issues in strong interaction physics, in particular the nature of the transition from the perturbative to non-perturbative regions of QCD. I summarize recent developments in quark-hadron duality in lepton-hadron scattering, and outline how duality can be studied at future high-luminosity facilities such as Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.

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Generalization of the alternate directions implicit technique is used to compute the pion propagator in quenched QCD on a lattice. The full four-dimensional problem is reduced to a series of partly decoupled two-dimensional inversions. Chiral properties of the theory computed in this approach agree with those found using other methods.

CERN Document Server

An energy frontier or QCD Explorer ep and collider can be realized by colliding high-energy photons generated by Compton backscattered off a CLIC electron beam, at either 75 GeV or 1.5 TeV, with protons or ions stored in the LHC. In this study we discuss a performance optimization of this type of collider by tailoring the parameters of both CLIC and LHC. An estimate of the ultimately achievable luminosity is given.

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Over 7000 events containing a fully reconstructed D{bar D} pair have been extracted from data recorded by the FOCUS photoproduction experiment at Fermilab. Preliminary results from a study of correlations between D and {bar D} mesons are presented. Correlations are used to study perturbative QCD predictions and investigate non-perturbative effects. We also present a preliminary result on the production of {psi}(3770).

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The correlation between baryon number and strangeness elucidates the nature of strongly interacting matter. This diagnostic can be extracted theoretically from lattice QCD calculations and experimentally from event-by-event fluctuations. The analysis of present lattice results above the critical temperature severely limits the presence of q{bar q} bound states, thus supporting a picture of independent (quasi)quarks. Details may be found in [1].

Science.gov (United States)

The extraction and recovery of cesium from simulated Purex waste solutions was successfully demonstrated in the pilot plant pulse column. Stable volumetric capacities as high as 670 gph/ft/sup 2/ (sum of both phases) were obtained for alkaline supernate-type waste; however, for efficient operation (transfer unit height - HTU -of two feet or less), the maximum throughput rate was limited to about 500 gph/ft/sup 2/. This rate could be achieved with feeds diluted to densities within 0.08 g/cc of the solvent density. Stable feed was prepared from simulated current, denitrated waste by addition of citric acid to complex the iron before neutralization to the desired operating pH of 7 to 8. Capacities of 500 gph/ft/sup 2/ were readily achieved with this feed, together with HTU's of 1.0 to 1.3 feet. Sodium extracted with the cesium was satisfactorily scrubbed from the solvent with a dilute citric acid solution. Scrub section sodium decontamination factors ...

Energy Technology Data Exchange (ETDEWEB)

The construction of networks consisting of optically interconnected processing units is a promising way to scale up quantum information processing systems. To store quantum information, single trapped atoms are among the most proven candidates. By placing them in high finesse optical resonators, a bidirectional information exchange between the atoms and photons becomes possible with, in principle, unit efficiency. Such an interface between stationary and ying qubits constitutes a possible node of a future quantum network. The results presented in this thesis demonstrate the prospects of a quantum interface consisting of a single atom trapped within the mode of a high-finesse optical cavity. In a two-step process, we distribute entanglement between the stored atom and two subsequently emitted single photons. The long atom trapping times achieved in the system together with the high photon collection efficiency of the cavity make the applied protocol in principle deterministic, allowing ...

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California s major energy utilities and the California Energy Commission (CEC) are seeking to allocate capital that yields the greatest return on investment for energy infrastructure that meets any part of the need for reliable supplies of energy. The utilities are keenly interested in knowing the amount of electrical energy savings that would occur if cool roof color materials are adopted in the building market. To meet this need the Oak Ridge National Laboratory and the Lawrence Berkeley National Laboratory (LBNL) have been collaborating on a Public Interest Energy Research (PIER) project to develop an industry-consensus energy-savings calculator. The task was coordinated with an ongoing effort supported by the DOE to develop one calculator to achieve both the DOE and the EPA objectives for deployment of cool roof products. Recent emphasis on domestic building energy use has made the work a top priority by the Department of Energy s (DOE) Building Technologies Program. The Roof ...

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Using the constrained-curve fitting method and overlap fermions with the lowest pion mass at 180 MeV, we observe that the masses of the first positive and negative parity excited states of the nucleon tend to cross over as the quark masses are taken to the chiral limit. Both results at the physical pion mass agree with the experimental values of the Roper resonance (N{sup 1/2+}(1440)) and S{sub 11} (N{sup 1/2-}(1535)). This is seen for the first time in a lattice QCD calculation. These results are obtained on a quenched Iwasaki 16{sup 3}x28 lattice with a=0.2 fm. We also extract the ghost {eta}{sup '}N states (a quenched artifact) which are shown to decouple from the nucleon interpolation field above m{sub {pi}}{approx}300 MeV. From the quark mass dependence of these states in the chiral region, we conclude that spontaneously broken chiral symmetry dictates the dynamics of light quarks in the nucleon.

Energy Technology Data Exchange (ETDEWEB)

Using the constrained curve fitting method and overlap fermions with the lowest pion mass at 180 MeV, we observe that the masses of the first positive and negative parity excited states of the nucleon tend to cross over as the quark masses are taken to the chiral limit. Both results at the physical pion mass agree with the experimental values of the Roper resonance (N{sup 1/2+} (1440)) and S{sub 11} (N{sup 1/2-}(1535)). This is seen for the first time in a lattice QCD calculation. These results are obtained on a quenched Iwasaki 16{sup 3} x 28 lattice with a = 0.2 fm. We also extract the ghost {eta}{prime} N states (a quenched artifact) which are shown to decouple from the nucleon interpolation field above m{sub {pi}} {approx} 300 MeV. From the quark mass dependence of these states in the chiral region, we conclude that spontaneously broken chiral symmetry dictates the dynamics of light quarks in the nucleon.

CERN Document Server

We summarize results of recent studies of heavy quarkonia correlators and spectral functions at finite temperatures from lattice QCD and systematic T-matrix studies using QCD motivated finite-temperature potentials. We argue that heavy quarkonia dissociation shall occur in the temperature range $1.2 \\le T_d/T_c \\le 1.5$ by the interplay of both screening and absorption in the strongly correlated plasma medium. We discuss these effects on the quantum mechanical evolution of quarkonia states within a time-dependent harmonic oscillator model with complex oscillator strength and compare the results with data for $R_{\\rm AA}/R_{\\rm AA}^{\\rm CNM}$ from RHIC and SPS experiments. We speculate whether the suppression pattern of the rather precise NA60 data from In-In collisions may be related to the recently discovered X(3872) state. Theoretical support for this hypothesis comes from the cluster expansion of the plasma Hamiltonian for heavy ...

CERN Document Server

We present several recent results from the BaBar collaboration in the areas of initial state radiation physics and transition form factors. An updated study of the processes e+e- -> K+K-pi+pi- and e+e- -> K+K-pi0pi0 provides an improved understanding of the Y(2175) meson. A very precise study of the process e+e- -> pi+pi- improves the precision on the calculated anomalous magnetic moment of the muon and provides by far the best information on excited rho states. Our previous measurements of the timelike transition form factors (TFF) of the eta and eta' mesons at Q^2=112 GeV^2, combined with new measurements of the their spacelike TFFs and those of the pi0 and eta_c mesons, provide powerful tests of QCD and models of the distribution amplitudes of quarks inside these mesons. The eta_c TFF shows the expected behavior over the Q^2 range 1-50 GeV^2, and we are sensitive to next-to-leading-order QCD corrections. The eta and eta' TFFs are ...

CERN Document Server

The Drell-Yan mechanism for the production of lepton pairs is one of the most basic processes for physics studies at hadron colliders. It is therefore important to have accurate theoretical predictions. In this work we compute the two-loop virtual mixed QCD x QED corrections to Drell-Yan production. We evaluate the Feynman diagrams by decomposing the amplitudes into a set of known master integrals and their coefficients, which allows us to derive an analytical result. We also perform a detailed study of the ultraviolet and infrared structure of the two-loop amplitude and the corresponding poles in epsilon.

International Nuclear Information System (INIS)

We construct a phenomenological model which describes the dynamical chiral symmetry breaking (DCSB) of a QCD vacuum and reproduces meson spectra. Quark condensates, the pion decay constant, and meson spectra are well reproduced by the phenomenological interaction which consists of a linear confining potential, a Coulombic potential, and the close-quote t Hooft determinant interaction. In this model, the close-quote t Hooft determinant interaction plays an important role to not only the mass difference between the #eta# and #eta#"' mesons, but other meson masses through DCSB. copyright 1997 The American Physical Society.

CERN Document Server

The branching ratio of J/psi-->K_S K_L is measured with improved precision to be B(J/psi-->K_S K_L) = (1.82\\pm 0.04\\pm 0.13)\\times 10^{-4}. using J/psi data collected with the Beijing Spectrometer (BESII) at the Beijing Electron-Positron Collider. This result is used to test the perturbative QCD ``12%'' rule between psi(2S) and J/psi decays and to investigate the relative phase between the three-gluon and one-photon annihilation amplitudes in J/psi decays.

International Nuclear Information System (INIS)

This paper describes the observation and partial wave analysis of 1203 (22 GeV) #pi#"-p #-># phi phi n events. This is an OZI suppressed channel in which the OZI suppression is found to be absent. Assuming QCD and the OZI rule as Ansatzen, it is concluded that the breakdown of the OZI suppression is due to glueballs. The g/sub T/(2160) and the g/sub T/(2320) with I/sup G/J/sup PC/ = 0"+2"+"+ are two resonances determined from the partial wave analysis. It is concluded that one or two primary glueballs with the above quantum numbers are responsible for the observed two states. A brief discussion of other glueball candidates and some relevant phenomenology is also included.

Science.gov (United States)

This report presents the operating results for Run 243 at the Advanced Coal Liquefaction R and D Facility in Wilsonville, Alabama. This run was made in an Integrated Two-Stage Liquefaction (ITSL) mode using Illinois 6 coal from the Burning Star mine. The primary objective was to demonstrate the effect of a dissolver on the ITSL product slate, especially on the net C/sub 1/-C/sub 5/ gas production and hydrogen consumption. Run 243 began on 3 February 1983 and continued through 28 June 1983. During this period, 349.8 tons of coal was fed in 2947 hours of operation. Thirteen special product workup material balances were defined, and the results are presented herein. 29 figures, 19 tables.

Science.gov (United States)

Biophysical Journal 8 (2):252-302. Acknowledgements: We wish to thank Kenneth Cheung, for writing the program to run the experiment and Joelle Schmidt- ...

Science.gov (United States)

... Thus initiation will be from the shock generated from the front surface of the pellet after traversing the inert packing. Exploding bridgewire detonator ...

Science.gov (United States)

... World Bank-run Afghanistan Reconstruction Trust Fund. ... No funds for Afghanistan have been held up ... Tehrik-e-Taliban Pakistan, TTP) is primarily ...

International Nuclear Information System (INIS)

In this paper, we study the J/#psi#(#UPSILON#) production in Z boson decay in a color-singlet model (CSM). We calculate the next-to-leading-order (NLO) QCD correction to Z#->#quarkonium+QQ, the dominant contribution in the CSM, with the vector and axial-vector parts in the ZQQ vertex being treated separately. The results show that the vector and axial-vector parts have the same K factor (the ratio of the NLO result to the leading-order result) 1.13 with the renormalization scale #mu#=2m_c and m_c=1.5 GeV, and the K factor falls to 0.918 when applying the Brodsky, Lepage, and Mackenzie (BLM) renormalization scale scheme with obtained #mu#_B_L_M=2.28 GeV and m_c=1.5 GeV. By including the contributions from the next-dominant ones, the photon and gluon fragmentation processes, the branching ratio for Z#->#J/#psi#_p_r_o_m_p_t+X is (7.3-10.0)x10"-"5 with the uncertainty consideration for the renormalization scale and charm quark mass. The results are about one-half ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

In clause it is shown a method optimization of brake of forces in view of a bias road it is established, that in mountain conditions of loss of coupling weight of automobiles than 2-3 times concerning flat conditions therma are more. The degree of use of coupling weight in result use of a regulator of brake forces very much increases also efficiency of brake systems such a kind of automobiles is provided with definition of optimum factor of coupling at which value of loss of coupling weight is provided minimal

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UK PubMed Central (United Kingdom)

The generation of synthetic forms of cellular life requires solutions...Full Text Available

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CERN Document Server

A major goal in optomechanics is to observe and control quantum behavior in a system consisting of a mechanical resonator coupled to an optical cavity. Work towards this goal has focused on increasing the strength of the coupling between the mechanical and optical degrees of freedom; however, the form of this coupling is crucial in determining which phenomena can be observed in such a system. Here we demonstrate that avoided crossings in the spectrum of an optical cavity containing a flexible dielectric membrane allow us to realize several different forms of the optomechanical coupling. These include cavity detunings that are (to lowest order) linear, quadratic, or quartic in the membrane's displacement, and a cavity finesse that is linear in (or independent of) the membrane's displacement. All these couplings are realized in a single device with extremely low optical loss and can ...

British Library Electronic Table of Contents (United Kingdom)

The interlayer exchange coupling between Co/Pt perpendicular-to-plane magnetized layers across a thin IrMn spacer layer was experimentally studied. In contrast to earlier studies on interlayer coupling through antiferromagnetic NiO, which revealed an oscillatory coupling behavior as a function of NiO thickness, a ferromagnetic coupling was observed here in the range of IrMn thickness between 0.6 and 1.5nm and antiferromagnetic between 1.5 and 2.5nm. The antiferromagnetic coupling is attributed to an orange peel magnetostatic mechanism whereas the ferromagnetic coupling is attributed to an out-of-plane polarization of the antiferromagnetic IrMn layer induced by the interfacial exchange interaction with the adjacent out-of-plane ferromagnetic layers. Measurements of hysteresis loops versus t...

International Nuclear Information System (INIS)

Possible anomalous top-quark couplings induced by SU(2)xU(1) gauge-invariant dimension-6 effective operators were studied in the process of ttbar productions and decays at polarized #gamma##gamma# colliders. Two CP-violating asymmetries, a linear-polarization asymmetry and a circular-polarization asymmetry, were computed including both non-standard ttbar#gamma# and #gamma##gamma#H couplings. An optimal-observable analysis for the process #gamma##gamma##->#ttbar#->#l"#+-# was performed in order to estimate the precision for determination of all relevant non-standard couplings, including the anomalous tbW coupling.

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The Tevatron Run 2 has begun. The Tevatron program in the next six years offers a real opportunity to significantly advance our understanding of the fundamental properties of the universe. It is an exciting, challenging program that goes straight to the highest priorities of high energy physics worldwide. The accelerator and detectors are being commissioned and seem to be performing well. We anticipate first physics results in the summer of 2002.

International Nuclear Information System (INIS)

It has been acknowledged that river morphology and hydrology have been intensively altered due to the anthropic demands in floodplain land use and management, flood protection, promotion of navigability or energy production. Rivers were transformed in water highways, having lost contact with their surrounding floodplain as well as the plethora of ecological processes and occupants once thriving in these ecotonal zones. The identification of this emerging threat of morphological and hydrological alteration on ecological integrity adds further complexity in the exploitation of hydrosystem resources. These resources are heavily coveted and guarded by different lobbies each having strategic views on future project development. Stakeholders may want to promote hydro-electricity, ecologists a natural reserve, communes may wish to have an increased flood protection and leisure promoters a nautical center. As a result, the proposition of a river development project is certain to face ...

CERN Document Server

We present an update of the most stringent experimental bounds on the trilinear R-parity violating couplings. We then analyse bounds on the R-parity violating couplings at the unification scale by renormalising the weak scale bounds. We derive unification scale upper bounds upon the couplings which are broadly independent of the fermion mass texture assumed. The R-parity violating couplings are factors of two to five more severely bounded at the unification scale than at the electroweak scale. In the presence of quark mixing, a few of the bounds are orders of magnitude stronger than their weak scale counterparts due to new R-parity violating operators being induced in the renormalisation between high and low scales. These induced bounds are fermion mass texture dependent. New bounds upon the weak scale couplings are obtained by the requirement of perturbativity between the weak and ...

Science.gov (United States)

A phase 2 study has been initiated to investigate surfactant-assisted coal liquefaction, with the objective of quantifying the enhancement in liquid yields and product quality. This report covers the second quarter of work. The major accomplishments were: completion of coal liquefaction autoclave reactor runs with Illinois number 6 coal at processing temperatures of 300, 325, and 350 C, and pressures of 1800 psig; analysis of the filter cake and the filtrate obtained from the treated slurry in each run; and correlation of the coal conversions and the liquid yield quality to the surfactant concentration. An increase in coal conversions and upgrading of the liquid product quality due to surfactant addition was observed for all runs.

British Library Electronic Table of Contents (United Kingdom)

This paper proposes a panel threshold cointegration approach to investigate the relationship between crude oil shocks and stock markets for the OECD and non-OECD panel from January 1995 to December 2009. Nonlinear cointegration is confirmed for the oil-stock nexus in the panel. Because threshold cointegration is found, the threshold vector error correction models can be run to investigate the presence of asymmetric dynamic adjustment. The Granger causality tests demonstrate the existence of bidirectional long-run Granger causality between crude oil shocks and stock markets for these OECD and non-OECD countries. However, the short-run Granger causality between them is bidirectional under positive changes in the deviation and unidirectional under negative ones. Moreover, the speed of adjustm...

Energy Technology Data Exchange (ETDEWEB)

We investigate the semihard production of neutral pseudoscalar and tensor mesons in high-energy [gamma][gamma] collisions (M=P=[pi][sup 0], [eta], [eta]' or M=T=a[sub 2], f[sub 2], f[sub 2]'). We deal with the exclusive [gamma][gamma][yields]MM' or semi-exclusive [gamma][gamma][yields]MX reactions (X is the hadron jet with not too large mass). The considered transfer momenta are small in comparison with the photon energies and they are large in comparison with the confinement scale. The amplitudes of these processes are determined by the odderon exchange, i.e. three-gluon exchange in the lowest order of perturbative QCD. The cross sections are calculated in this approximation. The possibility of measurements at LEP and at future [gamma][gamma] colliders is discussed. (orig.).

International Nuclear Information System (INIS)

Multiple Reggeon exchange supplies subleading logarithms that may be used to restore unitarity to the Low-Nussinov Pomeron, provided it can be proven that the sum of Feynman diagrams to all orders gives rise to such multiple Regge exchanges. This question cannot be easily tackled in the usual way except for very low-order diagrams, on account of delicate cancellations present in the sum which necessitate individual Feynman diagrams to be computed to subleading orders. Moreover, it is not clear that sums of high-order Feynman diagrams with complicated crisscrossing of lines can lead to factorization implied by the multi-Regge scenario. Both of these difficulties can be overcome by using the recently developed non-Abelian cut diagrams. We are then able to show that the sum of s-channel-ladder diagrams to all orders does lead to such multiple Reggeon exchanges. copyright 1997 The American Physical Society.

International Nuclear Information System (INIS)

The collisions of high energy photons produced at an electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the standard model. The luminosity and energy of the colliding photons produced by backscattering laser beams is expected to be comparable to that of the primary e"+e"- collisions. In this overview, we shall focus on tests of electroweak theory in photon-photon annihilation, particularly #gamma##gamma##->#W"+W"-, #gamma##gamma##->#Higgs bosons, and higher-order loop processes, such as #gamma##gamma##->##gamma##gamma#, Z#gamma# and ZZ. Since each photon can be resolved into a W"+W"- pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying WW collisions and annihilation. We also review high energy #gamma##gamma# tests of quantum chromodynamics, such as the scaling of the photon structure function, tt production, mini-jet ...

Energy Technology Data Exchange (ETDEWEB)

Energy flows in deep inelastic electron-proton scattering are investigated at a centre-of-mass energy of 296 GeV for the range Q{sup 2}{>=}10 GeV{sup 2} using the ZEUS detector. A comparison is made between events with and without a large rapidity gap between the hadronic system and the proton direction. The energy flows, corrected for detector acceptance and resolution, are shown for these two classes of events in both the HERA laboratory frame and the Breit frame. From the differences in the shapes of these energy flows we conclude that QCD radiation is suppressed in the large-rapidity-gap events compared to the events without a large rapidity gap. (orig.)

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We analyze the nucleon axial-vector coupling to two loops in chiral perturbation theory. We show that chiral extrapolations based on this representation require lattice data with pion masses below 300 MeV.

UK PubMed Central (United Kingdom)

Gastrin-releasing peptide receptor (GRPR), a member of the G protein-coupled receptor superfamily, has been utilized for receptor-mediated targeting of imaging and therapeutic agents; here we extend...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The authors derive in full details the Hamiltonian formulation of the N = 1D = 10 supergravity coupled to super Yang-Mills theory. In particular, they present the explicit form of the first class constraints and compute the constraints gauge algebra.

Energy Technology Data Exchange (ETDEWEB)

A Bragg waveguide consisting of multiple dielectric layers with alternating index of refraction becomes an excellent option to form electron accelerating structure powered by high power laser sources. It provides confinement of a synchronous speed-of-light mode with extremely low loss. However, laser field can not be coupled into the structure collinearly with the electron beam. There are three requirements in designing input coupler for a Bragg electron accelerator: side-coupling, selective mode excitation, and high coupling efficiency. We present a side coupling scheme using a distributed grating-assisted coupler to inject the laser power into the waveguide. Side coupling is achieved by a grating with a period on the order of an optical wavelength. The phase matching condition results in resonance coupling thus providing selective mode excitation capability. ...

International Nuclear Information System (INIS)

... mixing coupled channel theory differential cross sections excited states helium

International Nuclear Information System (INIS)

... coupling deformed nuclei gold 195 high spin states iridium 187 moment of

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A general analysis is presented of a photon storage cavity, coupled to free-electron laser (FEL) cavity. It is shown that if the coupling between the FEL cavity and the storage cavity is unidirectional (for example, a ring resonator storage cavity) then storage is possible, but that if the coupling is bi-directional then storage is not possible. Parameters are presented for an infra-red FEL storage cavity giving an order of magnitude increase in the instantaneous photon power within the storage cavity. 4 refs., 3 figs.

International Nuclear Information System (INIS)

In this paper, finite-difference time-domain method is used to research the transient electromagnetic pulse (EMP) coupling to the cylinder object which is shielded in another shielding cavity with a hole numerically. The different coupling effectiveness of three transient EMP is simulated. The distribution of the electric field in the shielding cavity and the current on the cavity are researched. The shielding effectiveness is evaluated. (authors)

UK PubMed Central (United Kingdom)

Stress strongly inhibits proliferation of granule cell precursors in the dentate gyrus, while voluntary running has the opposite effect. Few studies, however, have examined the possible effects...Full Text Available

Science.gov (United States)

Sep 28, 1990 ... RCA Whirlpool builtins, gas stove and cooktop,. 998-7872. Shelly,383-7153. '77 Ford Pinto. runs, needs some work. faded red, ...

UK PubMed Central (United Kingdom)

BackgroundIn rats, alcohol exposure during the period of rapid brain growth produces long-term changes in the free-running period, photoentrainment and phase-shifting...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Both DOE and DOD use water and/or steam in the process of removing high explosives, resulting in large quantities of contaminated water, which is then run through activated carbon, which then has to be decontaminated. Research has been underway to utilize microorganisms to degrade RDX and HMX.

CERN Multimedia

The head of KEK expressed his dismay that SLAC has entered into a collaboration with 3 other US labs and proposes to build the next linear collider at Fermilab, Ilinois. KEK wants the next accelerator to be built somewhere in the Asian Pacific region (1 page).

International Nuclear Information System (INIS)

This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO2) and sulfur dioxide (SO2) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO2 emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO2 emissions. Furthermore, the causality results show that the relationship between income and pollution in Tunisia is one ...

Energy Technology Data Exchange (ETDEWEB)

This report deals with the establishment of durability and reliability for the new type decompression brake system for large diesel engines. By testing engines on the bench, it has been found that the cylinder pressure, with the cylinder at the compression stroke upper dead center, imposed on the exhaust valve bevel section during brake operation constitutes the maximum load on the valve train system, that the cylinder pressure, with the cylinder at the compression stroke upper dead center, rises in proportion to a rise in the engine rpm, and that the load on the valve train system is at its maximum when the exhaust valve opens by brake operation. By examining the conditions whereunder a real vehicle was allowed to run, it has been found that the brake is applied approximately four times more often when the vehicle runs in a city area than on an expressway and that when running on the expressway the brake is often applied ...

CERN Document Server

The Daya Bay Neutrino Experiment is proposed to measure sin^2(2\\theta_{13}) to better than 0.01 at 90% C.L. in a three-year run. The experimental site, detector design, and background estimation are presented.

Energy Technology Data Exchange (ETDEWEB)

Taboada et al. have recently developed a computer model to predict gamma radiation doses to aircrews flying through nuclear-debris clouds. Although the model has the advantages of taking a large number of parameters into account and using the benchmark DELFIC code to model cloud dynamics, it takes up to 20 min for a single run on a mainframe computer. Results from a number of runs have been generalized into empirical formulae. From these results it is possible to estimate worst case gamma radiation doses for complex scenarios using a hand calculator.

Energy Technology Data Exchange (ETDEWEB)

The marine ram-type blowout preventer deployed from an offshore drilling rig has one serious disadvantage, its inaccessibility. A development to promote reliability of the subsea ram-type preventer and reduce the excess running and pulling to charge out rams, is the variable bare ram (VBR). Unlike the standard ram, the VBR has the ability to pack off a range of pipe sizes. Interest in VBR's has been revived and research and development in this equipment goes on at each of three manufacturer's facilities in Houston.

Energy Technology Data Exchange (ETDEWEB)

Results obtained on induced current and voltage caused by a high voltage transmission lines running parallel at a trolley bus contact lines, are presented. A computer program in Basic language, was developed to calculate the electric induction, problems of safety, a theoretical development and mathematical model of the electric factors between two lines (inductor and induced) are also discussed. 11 figs., 1 tab., 8 refs.

Science.gov (United States)

We present a high-statistics calculation of nucleon electromagnetic form factors in N{sub f}=2+1 lattice QCD using domain wall quarks on fine lattices, to attain a new level of precision in systematic and statistical errors. Our calculations use 32{sup 3}x64 lattices with lattice spacing a=0.084 fm for pion masses of 297, 355, and 403 MeV, and we perform an overdetermined analysis using on the order of 3600 to 7000 measurements to calculate nucleon electric and magnetic form factors up to Q{sup 2{approx_equal}}1.05 GeV{sup 2}. Results are shown to be consistent with those obtained using valence domain wall quarks with improved staggered sea quarks, and using coarse domain wall lattices. We determine the isovector Dirac radius r{sub 1}{sup v}, Pauli radius r{sub 2}{sup v} and anomalous magnetic moment {kappa}{sub v}. We also determine connected contributions to the corresponding isoscalar observables. We extrapolate these observables to the physical pion mass using ...

Energy Technology Data Exchange (ETDEWEB)

The quenched chiral logarithms are examined on a 163x28 lattice with Iwasaki gauge action and overlap fermions. The pion decay constant fpi is used to set the lattice spacing, a = 0.200(3) fm. With pion mass as low as {approx}180 MeV, we see the quenched chiral logarithms clearly in mpi2/m and fP, the pseudoscalar decay constant. The authors analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory (chiPT) to apply. With the constrained curve-fitting method, they are able to extract the quenched chiral logarithmic parameter delta together with other low-energy parameters. Only for mpi<=300 MeV do we obtain a consistent and stable fit with a constant delta which they determine to be 0.24(3)(4) (at the chiral scale Lambdachi = 0.8 GeV). By comparing to the 123x28 lattice, they estimate the finite volume effect to be about 2.7% for the smallest pion mass. They also fitted the pion mass to the form for the re-summed ...

International Nuclear Information System (INIS)

Strong coupled organic-inorganic microcavities device has been realized and studied. One of the two cavities contains an organic thin film of tetrakis(4-methoxyphenyl)porphyrin, whereas the other microcavity is a dielectric structure coupled to the organic one by means of a LiF/ZnS Bragg mirror. Reflectivity spectra show the presence of two well defined cavity dips. We observe an energy splitting of the two cavity-modes. Despite only one cavity contains the active layer, the photoluminescence spectra display two peaks at the same energy of the reflectivity dips. These observations indicate the strong coupling of the two cavities. The comparison of the diagonalized effective Hamiltonian with the observed resonances further confirms the strong coupling.

CERN Document Server

The celebrated Kuramoto model captures various synchronization phenomena in biological and man-made dynamical systems of coupled oscillators. It is well-known that there exists a critical coupling strength among the oscillators at which a phase transition from incoherency to synchronization occurs. This paper features three contributions. First, we characterize and distinguish the different notions of synchronization used throughout the literature and formally introduce the concept of phase cohesiveness as an analysis tool and performance index for synchronization. Second, we review the vast literature providing necessary, sufficient, implicit, and explicit estimates of the critical coupling strength in the finite and infinite-dimensional case. Finally, we present the first explicit necessary and sufficient condition on the critical coupling strength to achieve synchronization in the finite-dimensional ...

CERN Document Server

We investigate the effect of anomalous gamma-W-W couplings in e-gamma --> nu W through the angular and energy spectrum of the secondary leptons. Within the narrow-width approximation, a semi-analytical study of the secondary lepton energy-angle double distribution is considered. Utility of observables derived from this is demonstrated by considering the anomalous coupling, delta-kappa-gamma. Results of our investigation for typical ILC machine considered at Ecm = 300-1000 GeV re-affirms potential of this collider as a precision machine.

Energy Technology Data Exchange (ETDEWEB)

A process for the production of transportation fuels from heavy hydrocarbonaceous feedstock is provided comprising a two-stage, close-coupled process, wherein the first stage comprises a hydrothermal zone into which is introduced a mixture comprising a feedstock and red mud having coke-suppressing and demetalizing activity, and hydrogen; and the second, close-coupled stage comprises a hydrocatalytic zone into which substantially all the effluent from the first stage is directly passed and processed under hydrocracking conditions.

Energy Technology Data Exchange (ETDEWEB)

The problem of thermal instability of compressible, electrically conducting couple-stress fluids in the presence of a uniform magnetic field is considered. Following the linearized stability theory and normal mode analysis, the dispersion relation is obtained. For stationary convection, the compressibility, couple-stress, and magnetic field postpone the onset of convection. Graphs have been plotted by giving numerical values of the parameters to depict the stability characteristics. The principle of exchange of stabilities is found to be satisfied. The magnetic field introduces oscillatory modes in the system that were non-existent in its absence. The case of overstability is also studied wherein a sufficient condition for the non-existence of overstability is obtained. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The effect of the electric field on an exciton confined in a pair of vertically coupled quantum dots is studied. We use a single-band approximation and a parabolic model potential. As a result of these idealizations, we obtain a numerically solvable model, which is used to describe the influence of the electron-hole interaction on the Stark effect for the lowest-energy photoluminescence lines. We show that for intermediate tunnel coupling between the dots this interaction leads to an anomalous Stark effect with an essential deviation of the recombination energy from the usual quadratic dependence on the electric field.

Science.gov (United States)

... The unscented "sigma-point" Kalman filter "UKF ... set of carefully chosen sample points. ... Descriptors : *KALMAN FILTERING, *INERTIAL NAVIGATION ...

UK PubMed Central (United Kingdom)

The immediate early gene Arc is emerging as a versatile, finely tuned system capable of coupling changes in neuronal activity patterns to synaptic plasticity, thereby optimizing information...Full Text Available

Science.gov (United States)

For coupled quantum wires and dots, tunneling effects and coherent transport for quantum computing are being studied. In 2D systems, electron-hole bilayers for exciton...

International Nuclear Information System (INIS)

(Jun 1972). United States Woolson, WA Las Vegas, Nev. 18 Jun 1972.

UK PubMed Central (United Kingdom)

Orphan G protein-coupled receptors (GPCRs) are receptors lacking endogenous ligands. Found by molecular biological analyses, they became the roots of reverse pharmacology, in which receptors are attempted...Full Text Available

Science.gov (United States)

coupled heat/mass transfer Stefan problem. Taking the diffusion coefficient of Bi as a free parameter, the best fit was observed for the published value, ...

Energy Technology Data Exchange (ETDEWEB)

As a general approach to the problem of precursive behavior in alloys that undergo a displacive transformation, defect theories are becoming increasingly popular. However, the microscopic origin of the proposed defects is usually not considered. Yu and Anderson (1984) have argued that properties of strong-coupling superconductors, such as the A-15 compounds, imply a breakdown of Migdal's theorem (the adiabatic, or Born-Oppenheimer approximation for separation of electrons and phonons) in these systems. The electron-phonon coupling is so strong that it must be incorporated already in zeroth order. This is the basis for local phonon models, in which the electron-phonon coupling provides an effective double well potential for a localized group of atoms. The Yu-Anderson model and an analogous local Jahn-Teller model (Abell, 1983) are reviewed in connection with displacive transformations in ...

Energy Technology Data Exchange (ETDEWEB)

Code coupling activities have so far focused on coupling the neutronics modules with the CFD module. An interface module for the CFD-ACE/DeCART coupling was established as an alternative to the original STAR-CD/DeCART interface. The interface module for DeCART/CFD-ACE was validated by single-pin model. The optimized CFD mesh was decided through the calculation of multi-pin model. It was important to consider turbulent mixing of subchannels for calculation of fuel temperature. For the parallel calculation, the optimized decompose process was necessary to reduce the calculation costs and setting of the iteration and convergence criterion for each code was important, too.

International Nuclear Information System (INIS)

Using a realistic three-body model, angular distributions for the "1"6O(d,p)"1"7O(1/2"+) reaction, based on the channel coupling array (CCA) theory and various forms of the coupled reaction channel (CRC) method are compared. Despite the different forms and theoretical foundations of these methods, they yield similar angular distributions, within the bound state approximations used herein. The expected breaking of time reversal inveriance in the approximated CCA theory is quite small over most of the angular range. Of all the methods used, coupling effects in the forward directions are largest for the post form of the CRC, indicating that it is the least reliable of the CRC forms for fitting data. (Auth.).

International Nuclear Information System (INIS)

This chapter consists of some points including an introduction, the basic parts of mass spectroscope device, sample introduction into the inductively coupled plasma, pneumatic nebuliser, ultrasonic nebuliser, dry gas cloud system, laser ablation unit, inductively coupled plasma-ion source, extraction of ions from ion source, mass analysis, quad-polar mass spectrometer, dual assembly mass spectrometer, mass spectrometer by calculation of time of flight, ion interferences and the ability of resolution, ion counter, working conditions of inductively coupled plasma mass spectroscope device, efficiency of ion transportation in an inductively coupled plasma mass spectroscope device and applications of analysis using mass spectroscope of induced plasma including nuclear, industrial, geological, environmental and archaeological applications, measurement of isotopes ratio and applications in tracing crimes.

International Nuclear Information System (INIS)

(Jun 1972). United States Greene, NM Mynatt, FR Las Vegas, Nev. 18 Jun

Energy Technology Data Exchange (ETDEWEB)

Water protection wetlands aim to reduce nitrogen and phosphorous concentrations either separately or simultaneously. In the latter case, a wetland must contain parts differing clearly in both function and physical condition. In efforts to reduce nitrogen the most important process is denitrification. Phosphorus is deposited with solids and bound to the vegetation and soil in wetlands. As the bulk of the solid and nutrient load comes from catchments during spring floods, wetlands should be designed on the basis of, at least, the average maximum vernal run-off (MHq). Use of higher run-offs, e.g. MHql/10 or MHql/20, in the design without reducing the target retention would require large wetlands. The efficiency of wetlands is constrained by too short retention times and low leachate temperatures. Wetlands established with special environmental support are normally designed on the basis of MHq. The average catchment area of such wetlands is 1.86 ...

International Nuclear Information System (INIS)

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating variables are stored in a PC for off line ...

Energy Technology Data Exchange (ETDEWEB)

Local blood flow in the thigh was measured with /sup 133/Xe clearance technique in eight male distance runners after compression with a foam rubber compress and a standard elastic bandage. Two degrees of compression were tested, and an initial experiment with rested subjects was followed by a similar experiment immediately after running. Maximum compression exerted a cutaneous pressure of 85 (+/- 8) mm Hg and caused an immediate cessation of intra-muscular blood flow in the compressed area. Moderate compression gave a cutaneous pressure of 40 (+/- 5) mm Hg and resulted in a reduction of blood flow by approximately 50%. During compression, there were no significant differences in the blood flow of rested subjects compared to subjects immediately after running. In acute soft tissue injuries, a maximum compression bandage should effectively reduce or eliminate the formation of an intra-muscular hematoma, and an additive effect on blood flow of ice ...

Energy Technology Data Exchange (ETDEWEB)

This report describes a microcomputer-based, single-project financial analysis program: BREEDER. BREEDER is a user-friendly model designed to facilitate frequent and rapid analyses of the financial implications associated with alternative design and financing strategies for electric generating plants and large-scale prototype breeder (LSPB) reactors in particular. The model has proved to be a useful tool in establishing cost goals for LSPB reactors. The program is available on floppy disks for use on an IBM personal computer (or IBM look-a-like) running under PC-DOS or a Kaypro II transportable computer running under CP/M (and many other CP/M machines). The report documents version 1.5 of BREEDER and contains a user's guide. The report also includes a general overview of BREEDER, a summary of hardware requirements, a definition of all required program inputs, a description of all algorithms used in performing the construction-period ...

International Nuclear Information System (INIS)

Cross sections for (n,2n) (n,p) (n,#alpha#), and (n,d*)"1 reactions have been measured on ruthenium isotopes at the neutron energies of 13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Data are reported for the following reactions: "1"0"4Ru(n,2n)"1"0"3Ru, "9"8Ru(n,2n)"9"7Ru, "9"6Ru(n,2n)"9"5Ru, "9"6Ru(n,p)"9"6Tc"g, "9"6Ru(n,p)"9"6Tc"m, "1"0"4Ru(n,p)"1"0"4Tc, "1"0"2Ru(n,p)"1"0"2Tc"m, "1"0"4Ru(n,#alpha#)"1"0"1Mo, "1"0"2Ru(n,#alpha#)"9"9Mo, "9"6Ru(n,#alpha#)"9"3Mo"m, and "9"6Ru(n,d*)"9"5Tc"m. Results were discussed and compared with the previous works.

International Nuclear Information System (INIS)

A number of systems which can elucidate physics beyond the standard model are investigated. The production of axions by a network of cosmic strings in the early universe is calculated. This allows an upper bound to be placed on the axion decay constant, and provides the preferred Peccei-Quinn symmetry breaking scale for axions to make up the dark matter of the universe. Models of neutrino mass arising from strong interactions are investigated. These models possess a massless up quark, thereby solving the strong CP problem. A systematic analysis of the contributions to time reversal violating atomic and molecular electric dipole moments is presented. Specific contributions from the supersymmetric standard model are calculated. The contributions arising from the QCD vacuum angle are also discussed. Prospects for detecting the axion by its long range coherent force are related to measurable electron dipole moments. A method for measuring neutrino mass by nuclear ...

CERN Document Server

We present a detailed phenomenological study of direct photon production in association with a heavy-quark jet in pA collisions at the Relativistic Heavy Ion Collider (RHIC) and at the Large Hadron Collider (LHC) at next-to-leading order in QCD. The dominant contribution to the cross-section comes from the gluon--heavy-quark (gQ) initiated subprocess, making \\gamma + Q production a process very sensitive to both the gluon and the heavy-quark parton distribution functions (PDFs). Additionally, the RHIC and LHC experiments are probing complementary kinematic regions in the momentum fraction x_2 carried by the target partons. Thus, the nuclear production ratio R^{\\gamma+Q}_{pA} can provide strong constraints, over a broad x-range, on the poorly determined nuclear parton distribution functions which are extremely important for the interpretation of results in heavy-ion collisions.

CERN Document Server

It has by now been established that standard QCD factorization using transverse momentum dependent parton distribution functions fails in hadro-production of nearly back-to-back hadrons with high transverse momentum. The essential problem is that gauge invariant transverse momentum dependent parton distribution functions cannot be defined with process-independent Wilson line operators, thus implying a breakdown of universality. This has led naturally to proposals that a correct approach is to instead use a type of "generalized" transverse momentum dependent factorization in which the basic factorized structure is assumed to remain valid, but with transverse momentum dependent parton distribution functions that contain non-standard, process dependent Wilson line structures. In other words, to recover a factorization formula, it has become common to assume that it is sufficient to simply modify the Wilson lines in the parton correlation functions for each separate ...

Science.gov (United States)

Semi-inclusive pi+ electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range in Q2, x, z, and pT and over the complete range of azimuthal angles, phi, enabling us to separate the different structure functions, H2+eps*H1, H3 and H4. Our measurements of H2 at low-x were found to be in fairly good agreement with pQCD calculations, suggesting a precocious factorization of the process. Indeed, the conventional f(x)*D(z) term can account for almost all of the observed cross section, even at small z. The measured xF-distributions are in qualitative agreement with high energy data, which suggests a surprising numerical similarity between the spectator diquark fragmentation in the present reaction and the anti-quark fragmentation measured in e+e- collisions. We ...

Energy Technology Data Exchange (ETDEWEB)

We calculate the masses of the resonances D{sub s0}{sup *}(2317) and D{sub s1}(2460) as well as their bottom partners as bound states of a kaon and a D{sup (*)} - and B{sup (*)} -meson, respectively, in unitarized chiral perturbation theory at next-to-leading order. After fixing the parameters in the D{sub s0}{sup *}(2317) channel, the calculated mass for the D{sub s1}(2460) is found in excellent agreement with experiment. The masses for the analogous states with a bottom quark are predicted to be M{sub B{sup *}{sub s0}}=(5696{+-}40) MeV and M{sub B{sub s1}}=(5742{+-}40) MeV in reasonable agreement with previous analyses. In particular, we predict M{sub B{sub s1}}-M{sub B{sub s0}}{sup *}=46{+-}1 MeV. We also explore the dependence of the states on the pion and kaon masses. We argue that the kaon mass dependence of a kaonic bound state should be almost linear with slope about unity. Such a dependence is specific to the assumed molecular nature of the states. We suggest to extract the ...

CERN Document Server

The basic theoretical milestones were the Sakata SU(3) symmetry, the Goldberg-Ne'eman composite model with SU(3) triplets having baryon number (1/3) and the Nambu color gauge Lagrangian. The transition was led in right and wrong directions by experiments interpreted by phenomenology. A "good" experiment on $\\bar p p$ annihilation at rest showed that the Sakata model predictions disagreed with experiment. A "bad" experiment prevented the use of the Goldberg-Ne'eman triplet model to predict the existence and masses of the of the $\\Xi^*$ and $\\Omega^-$. More "good" experiments revealed the existence and mass of the $\\Xi^*$ and the $\\Omega^-$ and the absence of positive strangeness baryon resonances, thus confirming the "tenfold way". Further "good experiments" revealed the existence of the vector meson nonet, SU(3) breaking with singlet-octet mixing and the suppression of the $\\phi \\to \\rho \\pi$ decay. These led to the quark triplet model. The paradox of peculiar statistics then ...

CERN Document Server

The $\\bar{K}N$ system at threshold is a sensitive testing ground for low energy QCD, especially for the explicit chiral symmetry breaking. Therefore, we have measured the $K$-series x rays of kaonic hydrogen atoms at the DA$\\Phi$NE electron-positron collider of Laboratori Nazionali di Frascati, and have determined the most precise values of the strong-interaction energy-level shift and width of the $1s$ atomic state. As x-ray detectors, we used large-area silicon drift detectors having excellent energy and timing resolution, which were developed especially for the SIDDHARTA experiment. The shift and width were determined to be $\\epsilon_{1s} = -283 \\pm 36 \\pm 6 {(syst)}$ eV and $\\Gamma_{1s} = 541 \\pm 89 {(stat)} \\pm 22 {(syst)}$ eV, respectively. The new values will provide vital constraints on the theoretical description of the low-energy $\\bar{K}N$ interaction.

British Library Electronic Table of Contents (United Kingdom)

The generalized demodulation time-frequency analysis is a novel signal processing method, which is particularly suitable for the processing of multi-component amplitude-modulated and frequency-modulated (AM-FM) signals as it can decompose a multi-component signal into a set of single-component signals whose instantaneous frequencies own physical meaning. While fault occurs in gear, the vibration signals measured from gearbox would exactly display AM-FM characteristics. Therefore, targeting the modulation feature of gear vibration signal in run-ups and run-downs, a fault diagnosis method in which generalized demodulation time-frequency analysis and envelope order spectrum technique are combined is put forward and applied to the transient analysis of gear vibration signal. Firstly the multi-...

Energy Technology Data Exchange (ETDEWEB)

The TRIMPWR code has been developed as a post processor for TRIMHX (transient 3D diffusion code) in support of the reactor limits program. TRIMPWR is designed to produce JOSHUA files containing: core power as a function of time, assembly power by hex as a function of time, assembly power post peaking as a function of time, and axial power shapes for each assembly as a function of time (formatted for use by the FLOWTRAN code) from the output of a TRIMHX run. In an attempt to simplify the reactor limits process by reducing the number of assemblies which must be run through FLOWTRAN, TRIMPWR also sorts the assemblies by the product of the power post peaking and the maximum normalized axial power density for each assembly. This follows from the assumption that those assemblies having the maximum value of this product will have the most restrictive limits.

Science.gov (United States)

This report summarizes the 1981 operating and test data obtained at the six ton per day Advanced Coal Liquefaction Research and Development Facility in Wilsonville, Alabama. Special emphasis is placed on data accumulated during the fourth quarter of 1981. The Wilsonville R and D Facility was in operation 71% of 1981 (70% of the fourth quarter) with scheduled shutdowns accounting for 23% of the downtime (28% during the fourth quarter). Kentucky 9 coal from the Fies mine was processed in all runs conducted during 1981 (Runs 222 through 235). The hydrotreater (HTR) unit was brought on stream successfully in May 1981. The three process units of the Wilsonville facility were operated in a non-integrated mode during the second half of 1981. Significant data was obtained and is summarized.

International Nuclear Information System (INIS)

The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled fast reactor, which is designed to test a variety of different structural and fuel materials. A safety analysis is performed for each experiment that is irradiated in FFTF. The FFTF final safety analysis report (FSAR) assumed that all driver fuel assemblies would maintain cladding integrity during normal operations and all design transients. Maintenance of cladding integrity retains three barriers to any fission gas release to the public and also prevents any potential contact between the fuel and coolant. Experiments are, in general, expected to meet the same criterion. Selected experiments can, however, be classified as run-to-cladding-breach experiments (RTCB). The purpose of this paper is to describe alternative acceptance criteria for RTCB experiments that they feel provide protection equivalent to the maintenance of cladding integrity.

Science.gov (United States)

Numerical results on aeroelastic standard configurations are presented. The methods used for two dimensional configurations include the small perturbations approach for inviscid flow, coupling methods for unseparated flow, coupling methods for unseparated or separated, laminar or turbulent boundary layers, and a numerical solution of the Euler equations for inviscid flow. The three dimensional configurations are studied by the transonic small disturbance approach. The detailed results are given.

Energy Technology Data Exchange (ETDEWEB)

A method to deduce the 2 x 2 transport matrix for coupled heat and particle transport in Tokamaks is proposed. The method applies to perturbative experiments, and is based on a Fourier transform of the measured signals of temperature and density. By analyzing different linear combinations of temperature and density, the eigenvectors and eigenvalues of the transport matrix are determined. The method is tested for a number of illustrative cases using simulated data, and the sensitivity to noise on the signals is evaluated. (author).

International Nuclear Information System (INIS)

To simulate the effects of the breakup channel on rearrangement amplitudes, the conventional coupled-reaction-channel (CRC) expansion is augmented by pseudoreaction channels. The construction of the projector for the extended CRC space is discussed, and transition-operator equations on this space are given. By solving the full and post-approximation forms of the CRC equations for a model three-particle problem, the crucial role played by the nonorthogonality terms is demonstrated.

Energy Technology Data Exchange (ETDEWEB)

The relations between nuclear energy availability and nuclear plant safety are analyzed in the particular cases of naval propulsion nuclear boilers (aircraft carriers, submarines): safety objectives, present and potential risk analysis, optimization of the availability-safety couple, at the design stage and during operation (procedural rules related to the boiler state, real time decisions). 6 fig., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

The authors propose an integrated indicator of pump-rod couplings that allows both the couplings and the pump operations to be appraised according to the given formula. (Formula provided). The dynamic relationships of rod operations were determined with nomographs. These relationships involve such factors as: the type and size of the sucker-rod string; the pressure load at the equalizer head and its correlation to threshold pressure at pump discharge; pump diameter; the rod weight and construction; and integral reliability indicators.

Energy Technology Data Exchange (ETDEWEB)

The electroweak-symmetry-breaking sector of the standard model can be weakly-coupled or can be strongly-coupled, which is characterized by some kinds of strong interaction among the Goldstone bosons of the electroweak-symmetry-breaking sector. In this paper, we summarize an investigation of probing the strong electroweak-symmetry-breaking effects at photon colliders. ((orig.)).

Science.gov (United States)

The vibration behavior of turbomachine bladings is described, and the behavior of different kinds of coupled low pressure stages was experimentally investigated. Besides purely stationary flow conditions, conditions were also considered where pulsating fl...

Energy Technology Data Exchange (ETDEWEB)

The kinetic parameters, ..cap alpha.. the coupling coefficient and tau-bar the mean neutron transit time have been determined using a reactor oscillator on the coupled-core of the Queen Mary College research reactor. By using correlation techniques it has proved possible to use detectors small enough to be inserted in the fuel tanks. It is shown that the simplified Baldwin model with one-group diffusion theory is inadequate to describe the kinetic behaviour and the experimentally-determined parameters are dependent upon the positioning of the detectors.

Energy Technology Data Exchange (ETDEWEB)

The Albedo Theory was applied in order to develop an one-group algorithm for coupled neutron-gamma shielding calculations. The configuration analyzed consists of multilayered plane systems, where a incident neutron current generates gamma radiation through neutron-gamma reactions. The results obtained by Albedo Method and ANISN code have shown excellent agreement. (author)

Energy Technology Data Exchange (ETDEWEB)

A multi-group neutron-gamma cross-section library in DTF-IV format is supplemented with electron production matrix to generate a coupled neutron-gamma-electron library. This is realized by estimating the contributions from Compton scattering, pair production and photoelectric effect to the electron production cross-sections. A novel application of this new library, which involves transport of neutrons, gammas and electrons, for estimating the Compton current due to a pulse of radiation in air is discussed.

International Nuclear Information System (INIS)

A consistent mathematical derivation is given for the Sommerfeld fine structure electromagnetic coupling 1/?-bar 0=?0-bar 1/137.036. Following 't Hooft's holographic principle two complimentary forms of the derivation are given both leading to the E(?) theoretical value, namely ?-bar 0=(20)(1/?)4=137.082039311. The experimental value is subsequently found by projection as ?-bar 0(exp)=137/[cos(?/?-bar 0)]-bar 137.036.

International Nuclear Information System (INIS)

The onset of double-diffusive convection in a couple-stress fluid-saturated horizontal porous layer is studied using linear and weak nonlinear stability analyses. The modified Darcy equation that includes the time derivative term and the inertia term is used to model the momentum equation. The expressions for stationary, oscillatory and finite-amplitude Rayleigh number are obtained as a function of the governing parameters. The effect of couple-stress parameter, solute Rayleigh number, Vadasz number and diffusivity ratio on stationary, oscillatory and finite-amplitude convection is shown graphically. It is found that the couple-stress parameter and the solute Rayleigh number have a stabilizing effect on stationary, oscillatory and finite-amplitude convection. The diffusivity ratio has a destabilizing effect in the case of stationary and finite-amplitude modes, with a dual effect in the case of oscillatory convection. The ...

Energy Technology Data Exchange (ETDEWEB)

Magnetic coupling between two or more metal centers is an important facet of d- and f-block transition metal chemistry due to its implications in chemical bonding. With respect to actinide metals, magnetic coupling between polymetallic actinide centers is less well-known. Of the few documented examples, only one bimetallic uranium(V) complex, [(MeC{sub 5}H{sub 4}){sub 2}U]{sub 2}[{mu}-1,4-N{sub 2}C{sub 6}H{sub 4}] (1), has unequivocally demonstrated antiferromagnetic coupling. This complex employs a {pi}-conjugated 1,4-phenylenedimide ligand system which bridges the two f{sup 1}-metal centers and enables antiferromagentic coupling between unpaired f-e1ectrons residing in a {pi}-symmetry orbital. In this communication, we report the synthesis of a dimeric bis(imido) uranium(V) iodide complex and demonstrate with magnetic susceptibility measurements and density functional theory (DFT) calculations that ...

Energy Technology Data Exchange (ETDEWEB)

This study attempts to elucidate some of the effects of adding argon, neon and hydrogen to low pressure thermionically supported discharges used for plasma nitriding AISI M2 steel substrates. Four runs were performed at the same substrate temperature (550 C) and bias voltage (500 V), using the following gas mixtures: 8% N{sub 2} in Ar, 8% N{sub 2} in Ne, N{sub 2}+H{sub 2} in equal proportions, and N{sub 2} only. By careful control of the discharge parameters, most of the bombardment energy was transported to the substrates by 500 eV ions in all cases; these were mainly Ar{sup +} ions in the N{sub 2}+Ar run and N{sub 2}{sup +} ions in the other runs, notably by the action of Penning ionization in the N{sub 2}+Ne run. We found that the surface hardness was not significantly influenced by the type of ion delivering the bombardment energy, although we suggest that ions would need sufficient mass to cause ...

Energy Technology Data Exchange (ETDEWEB)

The proposed device incorporates an axle which has a roller bearing support mounted upon it. This support uses a cylindrical sleeve that comes in contact with the housing, the sensors, and the bearing support component. Metering accuracy is improved by placing roller bearing supports into grooves running through the protruding center sections of the sensor elements. These roller bearing supports interface with the cylindrical sleeve.

Energy Technology Data Exchange (ETDEWEB)

Cost and programmatic aspects of a recommended satellite power system are documented. Computer generated summaries are presented, and the detailed computer runs structured in a Work Breakdown Structure are given. The six configurations developed during the study period are summarized.

CERN Document Server

This comprehensive guide offers several tried and true steps to help you successfully manage the complex process of developing free software. Topics include project management, developer motivation, technical infrastructure to support collaboration, and project promotion. Producing Open Source Software is ideal for developers starting their own free software projects, or people who simply want to participate in the process.

Wastenet

... The moorland landscape looks especially colourful in late summer, while spring is the perfect time to come and see migrant birds like redstarts,...Valley This is a delightful oak woodland to walk through - especially in spring and early summer when lots of migrating birds come to breed ... Fowlmere Fowlmere's reedbeds and pools are fed by natural chalk springs, and a chalk stream runs through the reserve. Special birds ... There are common woodland birds in spring and turtle doves in spring and summer. Haweswater If you want to see a golden ...

British Library Electronic Table of Contents (United Kingdom)

Interchangeable technology from Flexicon Liquid Filling, a business division of Watson-Marlow Pumps Group, has helped family-run diagnostic reagent manufacturer, Hart Biologicals Ltd, to accommodate business growth with the recent upgrade to a tabletop bottle filling and capping machine. A peristaltic dispensing pump is crucial for succes

International Nuclear Information System (INIS)

The Finnish simulation code APROS and especially its 5-equation model is applied to modelling the horizontal steam generator. Different nodalizations are used in the secondary side of different models. Simulation results of the stationary state run are compared with results of RELAP5/MOD2 calculations and with an experimental plant data. (2 refs., 3 figs., 4 tabs.).

ScienceCinema

...in your blue fuller says global warming summit on the top general information ...this because a lot of times when we talk about global warming and climate change we really focus on the ice ...site ? one organization is called global warming one-on-one and it's run by ...can actually go to global warming one-on-one and and ...something to ? slow global warming but sometimes you feel alone so the big deal if i changed my life ...

Energy Technology Data Exchange (ETDEWEB)

The data taken at the Tevatron experiments have been analyzed to search for Higgs bosons. For the Standard Model Higgs searches, no excess is observed, the data are in good agreement with the expectations, so that limits are set on the production rates. For various theoretical models beyond the Standard Model, there is no excess either, which allows to derive constraints in their respective parameter spaces.

Energy Technology Data Exchange (ETDEWEB)

A low voltage FEL operating at 130 kV which can be run cw with a continuous electron beam current level up to 12 mA has been constructed for the X-Band microwave range (8-12 GHz). In this poster, we will report on the dependence on time, after the electron beam is switched on, of the growth and competition of those longitudinal modes in the cavity having nett gain.

Energy Technology Data Exchange (ETDEWEB)

The paper describes a way to control methane that is almost self-sufficient. The Methane Buster extracts methane from longwall mines. The machinery can run virtually unattended and is fuelled by a small proportion of the methane that it extracts. The most popular model is the size of a car and weighs 3000 lbs. With pump inlet sizes varying from 6 to 24 ins. The pumps can handle up to 30,000 CFM. 3 photos.

Energy Technology Data Exchange (ETDEWEB)

After the completion of the 4MWth pilot plant of the Pressurizied Internally Circulating Fluidized-bed Boiler (PICFB), a total of 15 test runs, amounting to 2280 hours of operation, were concluded. The test results have confirmed the superior operating performance. Additionally, Ebara plans to develop a Pressurized Internally Circulating Fluidized-bed Gasifier (PICFG or Advanced PICFB). 8 figs.

Energy Technology Data Exchange (ETDEWEB)

Explosives have been used in the removal of offshore wellhead devices for a number of years. In 1975, the first liquid explosives were run to remove wellheads and have proved to be a safe and reliable method of severing and salvaging the wellhead equipment from most depths of water. Methods of explosive wellhead removal and the areas of safety, reliability, and economics are discussed.

International Nuclear Information System (INIS)

In co-operation with the Scientific Planning Department of the Central Research Institute for Vessel- and Turbine Building the construction office of the turbine factory Charkow finished the draft of a slowly running (n = 1500 min"-"1) 2 GW-turboset for the operation of nuclear power plants. The chief purpose of the project was to determine the technical problems that are used to occur during the development of such steam turbines, as well as to settle the most favourable design. (orig./GL).

CERN Document Server

We make a complete analysis of the Yukawa coupling unification in SU(5) extensions of the MSSM in the framework of the radiative symmetry breaking scenario. Both logarithmic and finite threshold corrections of sparticles have been included in the determination of the gauge and Yukawa couplings at M_Z. The effect of the heavy masses of each model in the renormalization group equations is also included. We find that in the minimal SU(5) model b-tau Yukawa unification can be achieved for too large a value of alpha_s. On the other hand the Peccei-Quinn version of the Missing Doublet model, with the effect of the right handed neutrino also included, exhibits b-tau unification in excellent agreement with all low energy experimental data. Unification of all Yukawa couplings is also discussed.

CERN Document Server

We have combined perturbative unitarity and renormalisation group equation arguments in order to find a dynamical way to constrain the space of the gauge couplings ($g'_1$, \\widetilde{g}$) of the so-called "Minimal $Z'$ Models". We have analysed the role of the gauge couplings evolution in the perturbative stability of the two-to-two body scattering amplitudes of the vector and scalar sectors of these models and we have shown that perturbative unitarity imposes an upper bound that is generally stronger than the triviality constraint. We have also demonstrated how this method quantitatively refines the usual triviality bound in the case of benchmark scenarios such as the $U(1)_\\chi$, the $U(1)_R$ or the "pure" $U(1)_{B-L}$ extension of the Standard Model. Finally, a description of the underlying model structure in Feynman gauge is provided.

International Nuclear Information System (INIS)

The stability of a couple stress fluid saturated horizontal porous layer heated from below and cooled from above when the fluid and solid phases are not in local thermal equilibrium is investigated. The Darcy model is used for the momentum equation and a two-field model is used for energy equation each representing the solid and fluid phases separately. The linear stability theory is employed to obtain the condition for the onset of convection. The effect of thermal non-equilibrium on the onset of convection is discussed. It is shown that the results of the thermal non-equilibrium Darcy model for the Newtonian fluid case can be recovered in the limit as couple stress parameter C?0. We also present asymptotic analysis for both small and large values of the inter phase heat transfer coefficient H. We found an excellent agreement between the exact solutions and asymptotic solutions when H is very small.

International Nuclear Information System (INIS)

We consider a SQUID ring inductively coupled to an electromagnetic field mode, both treated quantum mechanically. We demonstrate a method for creating a maximally entangled state between the ring and the field mode. Our method utilises a non-adiabatic external magnetic flux pulse to move into and out of a transition region. Hence, our approach is fundamentally different to techniques based on Landau-Zener tunnelling that can also be used to achieve similar results. Our analysis is extended to include the effects of coupling the system to a dissipative environment. With this model we show that although such an environment makes a noticeable difference to the time evolution of the system, it need not destroy the entanglement of this coupled system over time scales required for quantum technologies.

International Nuclear Information System (INIS)

In this paper, a time-domain equivalent circuit method is applied to solve dispersion of coupled-cavity travelling-wave tube (CCTWT). First, the time-domain circuit equations of CCTWT coupled-cavity chain are deduced from the equivalent circuit model. Then, the equations are solved numerically by fourth-order Runge-Kutta method and a program CTTDCP is developed using MATLAB. Last, a L-band CCTWT is calculated using CTTDCP and the cavity pass-band of this tube is computed to be 1.08-1.48 GHz, which is consistent with the experimental results and the simulation results of electromagnetic code and demonstrates the validity of the time-domain equivalent circuit method. In addition, a new design method which uses the equivalent circuit method and electromagnetic simulation together to optimize the cold cavity characteristics of CCTWT is proposed. (authors)

CERN Document Server

We study perturbations of a Schwarzschild black hole in Chern-Simons modified gravity. We begin by showing that Birkhoff's theorem holds for a wide family of Chern-Simons coupling functions, a scalar field present in the theory that controls the strength of the Chern-Simons correction to the Einstein-Hilbert action. After decomposing the perturbations in spherical harmonics, we study the linearized modified field equations and find that axial and polar modes are coupled, in contrast to general relativity. The divergence of the modified equations leads to the Pontryagin constraint, which forces the vanishing of the Cunningham-Price-Moncrief master function associated with axial modes. We analyze the structure of these equations and find that the appearance of the Pontryagin constraint yields an overconstrained system that does not allow for generic black hole oscillations. We illustrate this situation by studying the case characterized by a ...

International Nuclear Information System (INIS)

We perform an optimal-observable analysis of the final charged-lepton/b-quark momentum distributions in #gamma##gamma##->#t t-bar #->#lX/bX for various beam polarizations in order to study possible anomalous t t-bar #gamma#, tbW and #gamma##gamma#H couplings, which could be generated by SU(2) x U(1) gauge-invariant dimension-6 effective operators. We find optimal beam polarizations that will minimize the uncertainty in determination of those non-standard couplings. We also compare e e-bar and #gamma##gamma# colliders from the viewpoint of the anomalous-top-quark-coupling determination.

CERN Document Server

We report electronic and magnetic structure of arsenic-doped manganese clusters from density-functional theory using generalized gradient approximation for the exchange-correlation energy. We find that arsenic stabilizes manganese clusters, though the ferromagnetic coupling between Mn atoms are found only in Mn$_2$As and Mn$_4$As clusters with magnetic moments 9 $\\mu_B$ and 17 $\\mu_B$, respectively. For all other sizes, $x=$ 3, 5-10, Mn$_x$As clusters show ferrimagnetic coupling. It is suggested that, if grown during the low temperature MBE, the giant magnetic moments due to ferromagnetic coupling in Mn$_2$As and Mn$_4$As clusters could play a role on the ferromagnetism and on the variation observed in the Curie temperature of Mn-doped III-V semiconductors.

British Library Electronic Table of Contents (United Kingdom)

Coupled continuous time random walks (CTRWs) model normal and anomalous diffusion of random walkers by taking the sum of random jump lengths dependent on the random waiting times immediately preceding each jump. They are used to simulate diffusion-like processes in econophysics such as stock market fluctuations, where jumps represent financial market microstructure like log returns. In this and many other applications, the magnitude of the largest observations (e.g. a stock market crash) is of considerable importance in quantifying risk. We use a stochastic process called a coupled continuous time random maxima (CTRM) to determine the density governing the maximum jump length of a particle undergoing a CTRW. CTRM are similar to continuous time random walks but track maxima instead of sums....

Science.gov (United States)

A detailed study has been performed for estimating the orbital energies, positions and shifts of the Lyman lines of C5+, Al12+ and Ar17+ under strongly coupled plasma with a view to understand such line positions and shifts obtained in laser produced plasma experiments. The effect of strongly coupled plasma has been treated within the Ion Sphere (IS) model. Both non-relativistic and relativistic methods have been used for estimating the spectral properties. Theoretical estimates with IS model of the plasma are in conformity with the results of laser plasma experiments on these highly stripped ions. The experimental data for the systems have also been compared with the theoretical estimates using Debye screening model of the plasma with spatial confinements which gives additional restrictions to the wave functions at finite boundaries.

Energy Technology Data Exchange (ETDEWEB)

The availability of dimeric Pt(I) complexes with bridging bis(diphenylphosphino)methane ligands, (L--L')/sup n+/, presents an opportunity to study the physical properties and reactivity of metal-metal bonds as a function of the ligand trans to it with a minimum of competing variables. Several interesting trends of Pt-P coupling constants with the Pt-L and Pt-Pt bond lengths in Pt(I) dimers, (L--L')/sup n+/, and structurally related Pt(II) complexes are reported here. The data indicate that the Pt-P coupling constants continue to be sensitive indicators of not only the structure and stereochemistry of platinum phosphine complexes but also the electronic and steric influences of the ligand in such complexes, 23 references, 1 figure, 4 tables.

Energy Technology Data Exchange (ETDEWEB)

The flexible, insulated, single strand cables are electrically connected with a cylindrical polar tip (PN) by means of cylindrical and conical shafts for the polar tips, which enter the faces of the divided, multiwire strand, clamped by tension half couplings. The flat ends of the polar tips being joined are positioned in two concentric mandrel bushings, an internal fixed one and an external, axially movable bushing (PV). The internal bushing is rigidly attached to the end of the left polar tip and equipped with three or four rounded, radial openings, whose diameter is determined by the external diameter of the locking device hinges (ShF) of the connecting couplings. The right polar tip is equipped with an annular channel of trapezoidal section into which the locking device hinges enter. The external movable bushing on the right side has a conical turning and on the left, a cylindrical into which the cylindrical spring which holds the movable ...

UK PubMed Central (United Kingdom)

Coupled rat heart mitochondria produce externally hydrogen peroxide at the rates which correspond to about 0.8 and 0.3 per cent of the total oxygen consumption at State 4 with succinate and...Full Text Available

UK PubMed Central (United Kingdom)

The network of coupled neurons in the pre-Bötzinger complex (pBC) of the medulla generates a bursting rhythm, which underlies the inspiratory phase of respiration. In some of these neurons,...Full Text Available

UK PubMed Central (United Kingdom)

The realization that there existed a G-protein coupled signal transduction mechanism developed gradually and was initially the result of an ill fated quest for uncovering the mechanism of action...Full Text Available

CERN Document Server

We present the minimal supersymmetric standard model with general broken R-parity, focusing on minimal supergravity (mSUGRA). We discuss the origins of lepton number violation in supersymmetry. We have computed the full set of coupled one-loop renormalization group equations for the gauge couplings, the superpotential parameters and for all the soft supersymmetry breaking parameters. We provide analytic formule for the scalar potential minimization conditions which may be iterated to arbitrary precision. We compute the low-energy spectrum of the superparticles and the neutrinos as a function of the small set of parameters at the unification scale in the general basis. Specializing to mSUGRA, we use the neutrino masses to set new bounds on the R-parity violating couplings. These bounds are up-to five orders of magnitude stricter than the previously existing ones. In addition, new bounds on the R-parity violating ...