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 Decade: 1990-1999
Radionuclide Coefficients for the BNL Site: For the Saturated and Unsaturated Zones

Radionuclide Coefficients for the BNL Site: For the Saturated and Unsaturated Zones

Date: February 1, 1999
Creator: Fuhrmann,M.
Description: The partition coefficient (K{sub d}) is defined as the concentration of a species of interest on the solid phase divided by the concentration of that species in the liquid phase, at steady-state. Therefore the lower the K{sub d}, the less sorption takes place. It is a parameter that is readily incorporated in chemical transport models. The K{sub d} approach to the partitioning of contaminants between soil and water in groundwater flow systems, is based on the assumption that sorption reactions are in equilibrium and are reversible. As a contaminant plume advances along flow paths, the movement of the front is retarded (relative to the movement of the groundwater) as a result of transfer of part of the contamination mass to the solid phase. If the input of contaminant mass to the system is discontinued, contaminants will be transferred back to the liquid phase as lower-concentration water flushes through the previously contaminated zone. Several sets of soil/water partition coefficients (K{sub d}) have been measured using BNL site specific soils and groundwater (with tracers added). They were all reported earlier through internal memos or reports. The K{sub d}s obtained for various radionuclides are determined experimentally with soils taken from different locations and ...
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A Pulsed Modulator Power Supply for the g-2 Muon Storage Ring Injection Kicker

A Pulsed Modulator Power Supply for the g-2 Muon Storage Ring Injection Kicker

Date: March 29, 1999
Creator: Mi,J.; Lee, Y.Y.; Morse, W. M.; Pai, C.; Pappas, G.; Sanders, R. et al.
Description: This paper describes the pulse modulator power supplies used to drive the kicker magnets that inject the muon beam into the g-2 storage ring that has been built at Brookhaven. Three modulators built into coaxial structures consisting of a series circuit of an energy storage capacitor, damping resistor and a fast thyratron switch are used to energize three magnets that kick the beam into the proper orbit. A 100 kV charging power supply is used to charge the capacitor to 95 kV. the damping resistor shapes the magnet current waveform to a 450 nanosecond half-sine to match the injection requirements. this paper discusses the modulator design, construction and operation.
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Phase IV Simulant Testing of Monosodium Titanate Adsorption Kinetics

Phase IV Simulant Testing of Monosodium Titanate Adsorption Kinetics

Date: September 29, 1999
Creator: Hobbs, D.T.
Description: The Salt Disposition Systems Engineering Team identified the adsorption kinetics of actinides and strontium onto monosodium titanate (MST) as a technical risk in several of the processing alternatives selected for additional evaluation in Phase III of their effort.
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I: Low Frequency NMR and NQR Using a dc SQUID. II: Variable-temperature 13C CP/MAS of Organometallics

I: Low Frequency NMR and NQR Using a dc SQUID. II: Variable-temperature 13C CP/MAS of Organometallics

Date: November 29, 1995
Creator: Ziegeweid, M.A.
Description: NMR and NQR at low frequencies are difficult prospects due to small nuclear spin polarization. Furthermore, the sensitivity'of the inductive pickup circuitry of standard spectrometers is reduced as the frequency is lowered. I have used a cw-SQUID (Superconducting QUantum Interference Device) spectrometer, which has no such frequency dependence, to study the local atomic environment of {sup 14}N via the quadrupolar interaction. Because {sup 14}N has spin I = 1 and a 0-6 MHz frequency range, it is not possible to obtain well-resolved spectra in high magnetic fields. I have used a technique to observe {sup 14}N NQR resonances via their effect on neighboring protons mediated by the heteronuclear dipolar interaction to study peptides and narcotics. The sensitivity of the SQUID is not enough to measure low-frequency surface (or other low spin density) systems. The application of spin-polarized xenon has been previously used to enhance polarization in conventional NMR experiments. Because xenon only polarizes spins with which it is in contact, it is surface selective. While differences in chemical shifts between surface and bulk spins are not large, it is expected that the differences in quadrupole coupling constant should be very large due to the drastic change of the electric field ...
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Unified Einstein-Virasoro Master Equation in the General Non-Linear Sigma Model

Unified Einstein-Virasoro Master Equation in the General Non-Linear Sigma Model

Date: June 5, 1996
Creator: Boer, J. de & Halpern, M.B.
Description: The Virasoro master equation (VME) describes the general affine-Virasoro construction $T=L^abJ_aJ_b+iD^a \dif J_a$ in the operator algebra of the WZW model, where $L^ab$ is the inverse inertia tensor and $D^a $ is the improvement vector. In this paper, we generalize this construction to find the general (one-loop) Virasoro construction in the operator algebra of the general non-linear sigma model. The result is a unified Einstein-Virasoro master equation which couples the spacetime spin-two field $L^ab$ to the background fields of the sigma model. For a particular solution $L_G^ab$, the unified system reduces to the canonical stress tensors and conventional Einstein equations of the sigma model, and the system reduces to the general affine-Virasoro construction and the VME when the sigma model is taken to be the WZW action. More generally, the unified system describes a space of conformal field theories which is presumably much larger than the sum of the general affine-Virasoro construction and the sigma model with its canonical stress tensors. We also discuss a number of algebraic and geometrical properties of the system, including its relation to an unsolved problem in the theory of $G$-structures on manifolds with torsion.
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Twining characters and orbit Lie algebras

Twining characters and orbit Lie algebras

Date: December 5, 1996
Creator: Fuchs, Jurgen; Ray, Urmie; Schellekens, Bert & Schweigert, Christoph
Description: We associate to outer automorphisms of generalized Kac-Moody algebras generalized character-valued indices, the twining characters. A character formula for twining characters is derived which shows that they coincide with the ordinary characters of some other generalized Kac-Moody algebra, the so-called orbit Lie algebra. Some applications to problems in conformal field theory, algebraic geometry and the theory of sporadic simple groups are sketched.
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Wakimoto realizations of current algebras: an explicit construction

Wakimoto realizations of current algebras: an explicit construction

Date: November 12, 1996
Creator: de Boer, Jan & Feher, Laszlo
Description: A generalized Wakimoto realization of $\widehat\cal G_K$ can be associated with each parabolic subalgebra $\cal P=(\cal G_0 +\cal G_+)$ of a simple Lie algebra $\cal G$ according to an earlier proposal by Feigin and Frenkel. In this paper the proposal is made explicit by developing the construction of Wakimoto realizations from a simple but unconventional viewpoint. An explicit formula is derived for the Wakimoto current first at the Poisson bracket level by Hamiltonian symmetry reduction of the WZNW model. The quantization is then performed by normal ordering the classical formula and determining the required quantum correction for it to generate $\widehat\cal G_K$ by means of commutators. The affine-Sugawara stress-energy tensor is verified to have the expected quadratic form in the constituents, which are symplectic bosons belonging to $\cal G_+$ and a current belonging to $\cal G_0$. The quantization requires a choice of special polynomial coordinates on the big cell of the flag manifold $P\backslash G$. The effect of this choice is investigated in detail by constructing quantum coordinate transformations. Finally, the explicit form of the screening charges for each generalized Wakimoto realization is determined, and some applications are briefly discussed.
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Monopole Condensation and Confining Phase of N=1 Gauge Theories Via M Theory Fivebrane

Monopole Condensation and Confining Phase of N=1 Gauge Theories Via M Theory Fivebrane

Date: August 7, 1997
Creator: de Boer, Jan & Oz, Yaron
Description: The fivebrane of M theory is used in order to study the moduli space of vacua of confining phase N=1 supersymmetric gauge theories in four dimensions. The supersymmetric vacua correspond to the condensation of massless monopoles and confinement of photons. The monopole and meson vacuum expectation values are computed using the fivebrane configuration. The comparison of the fivebrane computation and the field theory analysis shows that at vacua with a classically enhanced gauge group SU(r) the effective superpotential obtained by the"integrating in" method is exact for r=2 but is not exact for r> 2. The fivebrane configuration corresponding to N=1 gauge theories with Landau-Ginzburg type superpotentials is studied. N=1 non-trivial fixed points are analyzed using the brane geometry.
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Target space supersymmetric sigma model techniques

Target space supersymmetric sigma model techniques

Date: July 1, 1996
Creator: de Boer, Jan & Skenderis, Kostas
Description: We briefly review the covariant formulation of the Green-Schwarz superstring by Berkovits, and describe how a detailed tree-level and one-loop analysis of this model leads, for the first time, to a derivation of the low-energy effective action of the heterotic superstring while keeping target-space supersymmetry manifest. The resulting low-energy theory is old-minimal supergravity coupled to tensor multiplet. The dilaton is part of the compensator multiplet.
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Squarks in Tevatron dilepton events?

Squarks in Tevatron dilepton events?

Date: September 10, 1996
Creator: Barnett, R.M. & Hall, L.J.
Description: We consider unusual events in the CDF and D0 dilepton+jets sample with very high ET(lepton) and ET(missing). It is possible, but very unlikely, that these events originate from top quark pair production; however, they have characteristics that are better accounted for by decays of supersymmetric quarks with mass in the region of 300 GeV.
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Nucleon decay in GUT and nonGUT SUSY models

Nucleon decay in GUT and nonGUT SUSY models

Date: June 30, 1996
Creator: Murayama, Hitoshi
Description: I first emphasize the importance of searching for nucleon decay in the context of supersymmetric models. The status of minimal SUSY SU(5) model is reviewed, which can be definitively ruled out by a combination of superKamiokande andLEP-2 experiments. Non-minimal models may provide some suppression in the nucleon decay rates, but there is still a good chance for superKamiokande. I point out that the operators suppressed even by the Planck-scale are too large. We need a suppression mechanism for the operators at the level of 10-7, and the mechanism, I argue, may well be a flavor symmetry. A particular example predicts p --> K0e+ to be the dominant mode which does not arise in GUT models.
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F-Theory, T-Duality on K3 Surfaces and N = 2 Supersymmetric Gauge Theories in Four Dimensions

F-Theory, T-Duality on K3 Surfaces and N = 2 Supersymmetric Gauge Theories in Four Dimensions

Date: February 26, 1997
Creator: Hori, K. & Oz, Y.
Description: We construct T-duality on K3 surfaces. The T-duality exchanges a 4-brane R-R charge and a O-brane R-R charge. We study the action of the T-duality on the moduli space of O-branes located at points of K3 and 4-branes wrapping it. We apply the construction to F-theory compactified on a Calabi-Yau 4-fold and study the duality of N = 2 SU(N{sub c}) gauge theories in four dimensions. We discuss the generalization to the N = 1 duality scenario.
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Current Experiments in Particle Physics (September 1996)

Current Experiments in Particle Physics (September 1996)

Date: September 1, 1996
Creator: Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S. et al.
Description: This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.
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Will at least one of the Higgs bosons of the next-to-minimal supersymmetric extension of the standard model be observable at LEP2 or the LHC?

Will at least one of the Higgs bosons of the next-to-minimal supersymmetric extension of the standard model be observable at LEP2 or the LHC?

Date: June 24, 1996
Creator: Gunion, John F.; Haber, Howard E. & Moroi, Takeo
Description: We demonstrate that there are regions of parameter space in the next-to-minimal (i.e. two-Higgs-doublet, one-Higgs-singlet superfield) supersymmetric extension of the SM for which none of the Higgs bosons are observable either at LEP2 with $\sqrt{s}=192 GeV$ and an integrated luminosity of $L=1000inverse pb$ or at the LHC with $L=600 inverse fb$.
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Calculations of Higher Multipole Components in a Large Superconducting Quadrupole Magnet

Calculations of Higher Multipole Components in a Large Superconducting Quadrupole Magnet

Date: November 1, 1990
Creator: Napolitano, James
Description: We analyze the magnetic field of a finite length, large bore superconducting quadrupole magnet for use in a large aperture, high momentum magnetic spectrometer.In particular, we study the 12-pole and 20-pole components which would contribute to geometric aberations.The magnet is 130 cm long, has a pole radius of 4.3 cm, and the field is largely iron dominated.We analyze the magnet with a nominal field gradient of 276 gauss/cm.The field and/or the scalar potential is calculated with the program TOSCA and decomposed consistent with magnetostatic theory.We establish that the small multipole components are determined reliably and consistently.We find that although the absolute magnitude of the higher order multipoles can become quite large near the ends of the magnet, they reverse sign in this region and their contributions to the field integral are quite small.At the pole radius the integral contributions of the 12-pole (n=6) and 20-pole (n=10) are ~ 1.2*10^-2 and ~ 2.4*10^-
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Calculation of the Conditions for Bunched-Beam e-p Instability in the Los Alamos Proton Storage Ring (PSR)

Calculation of the Conditions for Bunched-Beam e-p Instability in the Los Alamos Proton Storage Ring (PSR)

Date: May 1, 1991
Creator: Neuffer, David
Description: Recent observations are consistent with the possibility of an
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Chemical Relaxation Times in a Hadron Gas at Finite Temperature

Chemical Relaxation Times in a Hadron Gas at Finite Temperature

Date: July 1, 1993
Creator: Goity, Jose
Description: The relaxation time of particle numbers in hot hadronic matter with vanishing baryon number are estimated using the ideal gas approximation and taking into account resonance decays and annihilation processes as the only sources of particle number fluctuations.Near the QCD critical temperature the longest relaxation times turn out to be of the order of 10 fm and grow roughly exponentially to become of the order of 10^3 fm at temperatures around 100 MeV.As a consequence of such long relaxation times, a clear departure from chemical equilibrium must be observed in the momentum distribution of secondary particles produced in high energy nuclear collisions.
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Duals for SU(N) SUSY Gauge Theories with an Antisymmetric Tensor: Five Easy Flavors

Duals for SU(N) SUSY Gauge Theories with an Antisymmetric Tensor: Five Easy Flavors

Date: December 16, 1997
Creator: Terning, John
Description: I consider N = 1 supersymmetric SU(N{sub c}) gauge theories with matter fields consisting of one antisymmetric representation, five flavors, and enough antifundamental representations to cancel the gauge anomaly. Previous analyses are extended to the case of even N{sub c} with no superpotential. Using holomorphy I show that the theory has an interacting infrared fixed point for sufficiently large N{sub c}. These theories are interesting due to the fact that in going from five to four flavors the theory goes from a non-trivial infrared fixed point to confinement, in contradistinction to SUSY QCD, but in analogy to the behavior expected in non-SUSY QCD.
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Dynamics of N = 2 Supersymmetric Gauge Theories in Three Dimensions

Dynamics of N = 2 Supersymmetric Gauge Theories in Three Dimensions

Date: March 21, 1997
Creator: de Boer, J.; Hori, K. & Oz, Y.
Description: We study the structure of the moduli spaces of vacua and superpotentials of N = 2 supersymmetric gauge theories in three dimensions. By analyzing the instanton corrections, we compute the exact superpotentials and determine the quantum Coulomb and Higgs branches of the theories in the weak coupling regions. We find candidates for non-trivial N = 2 superconformal field theories at the singularities of the moduli spaces. The analysis is carried out explicitly for gauge groups U(N{sub c}) and SU(N{sub c}) with N{sub f} flavors. We show that the field theory results are in complete agreement with the intersecting branes picture. We also compute the exact superpotentials for arbitrary gauge groups and arbitrary matter content.
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Hadronic loops and the OZI rule

Hadronic loops and the OZI rule

Date: August 1, 1991
Creator: Isgur, Nathan
Description: Arguments based on unitarity indicate that hadronic loop diagrams should produce large violations of the OZI (Okubo-Zweig-Iizuka) rule. The mechanism by which these corrections are evaded has long been a mystery. We have found that there is an exact cancellation of all such loops in a particular (quark model) limit and that, at least for the rho-->omega system which we have studied in detail, the cancellation is maintained in a realistic calculation which takes into account departures from this limit.
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The heavy expansion in B decays

The heavy expansion in B decays

Date: August 1, 1993
Creator: Roberts, Winston & Roberts, Winston
Description: We examine the 1/mc and 1/mb expansions in B^(*)->D^(*) processes, and point out that there are relationships among the form factors that do not receive corrections in any order of 1/mc.A different set of relationships are unchanged by (1/mc)^n corrections, while the (1/mc)^n preserved relationships are also unaffected by terms proportional to powers of Alphas(mc).All relationships are modified when terms of the form 1/(mbmc) or radiative corrections proportional to powers of Alphas(mb) are included.
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The Heavy Mass Expansion lambda(sub)b -> lambda(sub)c Decays

The Heavy Mass Expansion lambda(sub)b -> lambda(sub)c Decays

Date: November 1, 1992
Creator: Mannel, Thomas & Roberts, Winston
Description: We point out that in the decays of the lambda(sub)b to lambda(sub)c one can find predictions which - in the framework of the 1/m(sub)c expansion - do not receive corrections in any order of 1/m(sub)c. We discuss QCD corrections to these predictions and examine some of the consequences for nonleptonic decays.
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1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

Date: February 1, 1992
Creator: Roberts, Winston
Description: We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda<sup>+</sup><sub>c</sub> -> lambda e<sup>+</sup> nu, to order 1/m<sub>c</sub>. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.
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Recent Progress in Weakly-Coupled Heterotic String Phenomenology

Recent Progress in Weakly-Coupled Heterotic String Phenomenology

Date: July 28, 1997
Creator: Wu, Yi-Yen
Description: Some recent developments in the weakly-coupled heterotic string phenomenology are reviewed. We discuss several important issues such as dilaton/moduli stabilization, supersymmetry breaking (by hidden-sector gaugino condensation), gauge coupling unification (or the Newton's constant), the QCD axion, as well as cosmological problems involving the dilaton/moduli and the axion.
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