CERN Document Server

We explore the structure of a new family gauge symmetry U(3) and show its experimental signatures to search for. U(3) gauge bosons obviate an unwelcome deviation of the charged lepton mass formula with the running masses from that with the pole masses. The current structure of this model leads to flavor number violations via exchange of extra gauge bosons. We obtain bounds on the masses of the gauge bosons from rare kaon decay searches and muonium-antimuonium oscillation searches. We propose attractive signatures at LHC and lepton colliders and discuss feasibility of their discovery.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Relatively low molecular weights polyelectrolytes (10{sup 4}-10{sup 6}) behave as worm-like chain when electrostatic repulsions are assumed to govern the excluded volume parameter. Under such conditions, predictions of chain expansion and effect of polyelectrolyte concentrations are made assuming that unperturbed dimensions could be obtained at infinite salt content. Experimental studies of an ionic polysaccharide, namely the Na-hyaluronate, were done and the values obtained for the radius of gyration as well as the intrinsic viscosity at different charge densities are in good agreement with the predictions.

Science.gov (United States)

The electromagnetic properties of the baryon decuplet are calculated in quenched QCD on a 20{sup 3}x40 lattice with a lattice spacing of 0.128 fm using the fat-link irrelevant clover fermion action with quark masses providing a pion mass as low as 300 MeV. Magnetic moments and charge radii are extracted from the electric and magnetic form factors for each individual quark sector. From these, the corresponding baryon properties are constructed. We present results for the higher-order moments of the spin-3/2 baryons, including the electric-quadrupole moment E2 and the magnetic-octupole moment M3. The world's first determination of a nonzero M3 form factor for the {delta} baryon is presented. With these results we provide a conclusive analysis which shows that decuplet baryons are deformed. We compare the decuplet-baryon results from a similar lattice calculation of the octet baryons. We establish that the environment sensitivity is far less pronounced for ...

Energy Technology Data Exchange (ETDEWEB)

The Linac Coherent Light Source (LCLS) is an x-ray free-electron laser (FEL) project based on the SLAC linac. The LCLS Photoinjector beamline has been designed to deliver 10-ps long electron bunches of 1 nC with a normalized projected transverse emittance smaller than 1.2 mm-mrad at 135 MeV. Tolerances and regulation requirements are tight for this tuning. Half of the total emittance at the end of the injector comes from the ''cathode emittance'' which is 0.7 mm-mrad for our nominal 1nC tuning. As the ''cathode emittance'' scales linearly with laser spot radius, the emittance will be dramatically reduced for smaller radius, but this is only possible at lower charge. In particular, for a 0.2 nC charge, we believe we can achieve an emittance closer to 0.4 mm-mrad. This working point will be easier to tune and the beam quality should ...

International Nuclear Information System (INIS)

A technique for calculation of the total weight of quark clusters-fluctons: in nuclei is developed. Blokhintsev's formula is justified microscopically and refined by introduction of spin-charge and quark factors. It is shown that the large values of the correlation radius (R/sub C/#approx =#0.75 fm or 1.0 fm) derived from experimental data in various papers using this formula correspond to #left brace#similarreverse arrowto#right brace#2.5 times smaller internucleon distances in the flucton (0.3--0.4 fm), i.e., the hardness of fluctons is caused by unsuppressed manifestation of hidden color at such distances (the corresponding probabilities are presented).

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 ...

Energy Technology Data Exchange (ETDEWEB)

This work is based on the study of cesium ({sup 118,146}Cs) and francium ({sup 207-213}Fr,{sup 220-228}Fr) isotopes by hyperfine atomic spectroscopy and on the interpretation of these results from the nuclear physics point of view. The measured nuclear quantities are: the spin, the magnetic moment, the electric quadrupole moment and the mean square charge radius. The experimental method which is based on hyperfine optical pumping with a tunable laser, followed by magnetic analysis of the atoms is described in the first part. Results related to atomic physics are also presented. In the second part, these data are interpreted in the framework of nuclear models. The deformation of light cesium isomers are compared to values obtained from a theoretical self-consistent calculation. Heavy francium isotopes are situated in an area where the existence of static octupole deformations have been predicted. The odd-even staggering measured on the mean ...

Energy Technology Data Exchange (ETDEWEB)

This paper develops a clear procedure for solving the nonlinear Vlasov-Maxwell equations for a one-component intense charged particle beam or finite-length charge bunch propagating through a cylindrical conducting pipe (radius r = r(subscript)w = const.), and confined by an applied focusing force. In particular, the nonlinear Vlasov-Maxwell equations are Lorentz-transformed to the beam frame ('primed' variables) moving with axial velocity relative to the laboratory. In the beam frame, the particle motions are nonrelativistic for the applications of practical interest, already a major simplification. Then, in the beam frame, we make the electrostatic approximation which fully incorporates beam space-charge effects, but neglects any fast electromagnetic processes with transverse polarization (e.g., light waves). The resulting Vlasov-Maxwell equations are then Lorentz-transformed back to ...

International Nuclear Information System (INIS)

The authors search for the extended conformal algebra with two spin-s (s:integer) and one spin-1 generators. This search is inspired by the existence of chiral algebra in the Gaussian model for rational radius. For odd s, the conformal properties of the three-point functions imply that a general fusion rule can be reduced to those of the Gaussian model. For arbitrary even s, these conditions are weaker. In particular, for s = 2 the authors show that the chiral algebra of the Gaussian model is the unique extended conformal algebra with the value of the central charge fixed to be c = 1. It is also shown that the conformal generator is necessarily a bilinear of the spin-1 generator just as the Gaussian model. The authors conjecture that this remains true for arbitrary value of s.

International Nuclear Information System (INIS)

This paper describes stable strontium as composed of four stable isotopes ( Sr 88, Sr 87, Sr 86, and Sr 84), of which Sr 88 contributes more than 82% to its composition. Strontium exists in three crystalline, plymorphic forms; face-centered cubic alpha form, hexagonal beta form and body-centered cubic gamma form. Strontium occupies in many physicochemical aspects an intermediate position between calcium and barium, as does the solubility of strontium salts. As a result of its oxidation potential, strontium readily forms oxides, halides, and sulfide. The author proposes that the slight discrimination against strontium incorporation into bony tissues may be due to the difference in ionic potential (14%) between strontium and calcium. Ionic potential is an indicator of the strength of ionic bonds: strontium has a smaller ratio of ionic charge to ionic radius when compared with calcium.

Energy Technology Data Exchange (ETDEWEB)

Laser spectroscopy measurements have been performed on neutron deficient iridium isotopes. The hyperfine structure and isotope shift of the optical Ir I transition 5d{sup 7}6s{sup 24}F{sub 9/2} {sup {yields}} 5d{sup 7}6s6p {sup 6}F{sub 11/2} at 351.5 nm have been studied for the {sup 182-189}Ir, {sup 186}Ir{sup 1}m and {sup 191,193}Ir isotopes. The nuclear magnetic and quadrupole moments were obtained from the HFS measurements and the changes of the mean square charge radii from the IS measurements. A large mean square charge radius change between {sup 187}Ir and {sup 186}Ir and between {sup 186}Ir{sup 1}m and {sup 186}Ir{sup 1}g has been observed.

CERN Document Server

The radiative decay K->mu nu gamma has been studied at ISTRA+ setup in a new kinematical region. About 46K events of K->mu nu gamma have been observed. The sign and value of Fv-Fa have been measured for the first time. The result is Fv-Fa=0.16(4)(5).

Energy Technology Data Exchange (ETDEWEB)

The fine scale mechanical probing capability of NI-AFM was used to examine hydrogen interaction with plasticity. To realize this, an electrochemical three electrode setup was incorporated into the NI-AFM. The developed ECNI-AFM is capable of performing nanoindentation as well as imaging surfaces inside electrolytes. The developed ECNI-AFM setup was used to examine the effect of cathodically charged hydrogen on dislocation nucleation in pure metals and alloys. It was shown that hydrogen reduces the pop-in load in all of the tested materials except Cu. The reduced pop-in load can be interpreted as the HELP mechanism. Classical dislocation theory was used to model the homogeneous dislocation nucleation and it was shown that H reduces the activation energy for dislocation nucleation in H sensitive metals which are not undergoing a phase transformation. The activation energy for dislocation nucleation is related to the material specific parameters; shear modulus {mu}, ...

International Nuclear Information System (INIS)

Elise is a heavy ion induction linear accelerator that will demonstrate beam manipulations required in a driver for inertial fusion energy. With a line charge density similar to that of heavy ion drivers, Elise will accelerate a #>=# 1 gs beam pulse of K"+ ions from an initial energy of 2 MeV to a final energy #>=# 5 MeV. In the present design, the Elise electrostatic quadrupoles (ESQ) will have a 2.33 cm radius aperture operating at #+-#59 kV. The half-lattice periods range from 21 cm to 31 cm. The entire machine will be approximately 30 m long, half of that is the induction accelerator and the remaining half is the injector (including the Marx generator) and the matching section. Elise will be built in a way that allows future expansion into the full ILSE configuration, therefore it will have an array of four ESQ focusing channels capable of transporting up to a total of 3.2 A of beam current. Elise will also have an active alignment ...

CERN Document Server

Attention is paid to the production mechanisms of light scalars that reveal their nature. We reveal the chiral shielding of the \\sigma(600) meson. We show that the kaon loop mechanism of the \\phi radiative decays, ratified by experiment, points to the four-quark nature of light scalars. We show also that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor q\\bar q mesons that are produced via two-quark transitions $\\gamma\\gamma\\to q\\bar q$. The history of spontaneous breaking of symmetry in quantum physics is discussed in Appendix.

Science.gov (United States)

Derivations are made for the mass and the mass-turnover time scale of an accretion disk as a function of the accretion rate, the observed disk radius, the non-viscous disk radius, and two parameters. These parameters depend on the effectiveness of viscosity and tidal angular momentum loss. Application is made to DQ Herculis.

Energy Technology Data Exchange (ETDEWEB)

This work has analyzed the key variables of indentation tip radius, contact radius, delamination radius, residual stress and superlayer/film/interlayer properties on nanoindentation measurements of adhesion. The goal to connect practical works of adhesion for very thin films to true works of adhesion has been achieved. A review of this work titled ''Interfacial toughness measurements of thin metal films,'' which has been submitted to Acta Materialia, is included.

CERN Document Server

We discuss an experimental technique aimed at tagging electron neutrinos in multi-GeV artificial sources on an event-by-event basis. It exploits in a novel manner calorimetric and tracking technologies developed in the framework of the LHC experiments and of rare kaon decay searches. The setup is based on an instrumented decay tunnel equipped with tagging units that intercept secondary and tertiary leptons from the bulk of undecayed pi+ and protons. We show that the taggers are able to reduce the nue contamination originating from K_e3 decays by about one order of magnitude. Only a limited suppression (~60%) is achieved for nue produced by the decay-in-flight of muons; for moderate beam powers, similar performance as for K_e3 can be reached supplementing the tagging system with an instrumented beam dump.

Science.gov (United States)

major radius of the toroidal containment volume. The containment time was calculated using equation (4) as derived in references 16 and 17. The solid ...

British Library Electronic Table of Contents (United Kingdom)

The rolls and stand deflections induced by rolling force lead to a significant decrease in the radius prediction accuracy of the ring product in the in-plane roll-bending of strip. To precisely predict the deflections and control the radius, a new analytical model is developed. Numerical implementation is presented to solve the theoretical rolling force, the deflections as well as the inherent force-deflection relationship considering the interactions of the strip workpiece, the rolls and the stand. A series of profile measurements of the formed ring parts are made to assess the accuracy of the predicted deflections. Different control approaches are used in the experiments to validate the radius control model. The experimental results show that the model is reliable to control the radii wi...

Science.gov (United States)

... GUN PROPELLANTS, GUN CHAMBERS, PROPELLANT GRAINS, HOWITZERS, COMBUSTIBLE CARTRIDGE CASES, ZONE CHARGES. ...

Energy Technology Data Exchange (ETDEWEB)

Wonderful opportunities await particle physics over the next decade, with the coming of the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. Here I have in mind the work of the B factories and the Tevatron collider on CP violation and the weak interactions of the b quark; the wonderfully sensitive experiments at Brookhaven, CERN, Fermilab, and Frascati on CP violation and rare decays of kaons; the prospect of definitive accelerator experiments on neutrino oscillations and the nature of the neutrinos; and a host of new experiments on the sensitivity frontier. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the ...

Science.gov (United States)

An approximate method of calculating the radius of thawing around an injection well is presented. The method is based on the assumption that for a cylindrical system the position of the phase interface in the Stefan problem can be approximated through two functions: one function determines the position of the melting-temperature isotherm in the problem without phase transitions and the second function does not depend on time. The adjusted heating time concept was used to describe the first function. The second function is a known analytical relationship and is expressed in terms of ice content, thermal properties of thawed/frozen formations, formation temperature and the temperature of the injected fluid. Simple approximate formulae are suggested to estimate the duration of the freezeback period. To verify the proposed formulae, the results of numerical solutions were used. An example which shows that the duration of the 'safety period' (free from freezing of water ...

CERN Document Server

We present a set of structural parameters for the central parts of 57 early-type galaxies observed with the Planetary Camera of the Hubble Space Telescope. These parameters are based on a new empirical law that successfully characterizes the centers of early type galaxies. This empirical law assumes that the surface brightness profile is a combination of two power laws with different slopes gamma and beta for the inner and outer regions. Conventional structural parameters such as core radius and central surface brightness are replaced by break radius r_b, where the transition between power-law slopes takes place, and surface brightness mu_b at that radius. An additional parameter alpha describes the sharpness of the break. The structural parameters are derived using a chi-squared minimization process applied to the mean surface brightness profiles. The resulting model profiles generally give very good agreement to the ...

Energy Technology Data Exchange (ETDEWEB)

We have constructed models for the vertical structure of disks around a black hole of 10/sup 6/ M/sub sun/ at distances from it smaller than the tidal breakup radius. These disks are massive enough that nuclear burning occurs in their central layers.

Science.gov (United States)

The GBM location uncertainties range from 5-15deg (radius, 1 sigma, stat+sys). ... The site's dis/enabling on Notice types and their other filter criteria .... Fermi Pointing Direction Notice gives the current pointing direction of the ...

Energy Technology Data Exchange (ETDEWEB)

The dependence of the rms radius of the deuteron cluster in /sup 6/Li on the relative d-..cap alpha.. momentum was investigated on the basis of the three-body wave function given by Rai, Lehman, and Ghovanlou.

UK PubMed Central (United Kingdom)

Charge-charge interactions dramatically influence the dissociation and proton transfer reactivity of large multiply protonated ions. In combination with tandem mass spectrometry, proton transfer...Full Text Available

Science.gov (United States)

A reactor was proposed in which the breeder mantel would consist of a charge of homogeneous cast breeder elements, so that the breeder element has the same shape as the fuel elements. By this method it would be possible to use the breeder element after its irradiation immediately for the charging of the fuel elements.

International Nuclear Information System (INIS)

The formation of the ions charge and energy distributions of the ions slowed down or randomly changing their charge in the collisions with the medium particles are studied. The effect of the ions dispersion by the charge on the Bragg curve form is investigated. The proposed diffusion approximation for the heavy ions kinetic equation makes it possible to determine simply the parameters of the ions distribution by charge and energy on the whole way of the ions motion. The relation between the ions charge distribution characteristics and the cross sections of the ionization-recombination processes is indicated. The ions distributions, calculated in the proposed analytical model, are compared with the results of the numerical calculations. Good agreement between the analytical, numerical and experimental results is obtained

Science.gov (United States)

... In the Proceedings of INTC 2003, we studied charging effects on target coverage during electrospinning (16). ... of Fibers from Electrospinning of ...

Energy Technology Data Exchange (ETDEWEB)

Short communication.

Science.gov (United States)

... Descriptors : *PROPELLING CHARGES, *NITROCELLULOSE, *COMBUSTIBLE CARTRIDGE CASES, DENSITY, FIBERS, MANUFACTURING ...

Energy Technology Data Exchange (ETDEWEB)

Implementation of a plan to charge waste management costs to the facility that generates such waste requires a long-term commitment and consistent administration. The benefit is that generators are provided the incentive to optimize waste management practices if the charges are appropriately applied. This paper summarizes (1) a plan to charge waste generators, (2) the administrative structure of the plan, (3) a comparison between the rate structure and changes in waste disposal operations, and (4) issues that have surfaced as the plan is implemented. 2 refs., 1 fig., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

... Part A: The electromagnetic radiation of a charged tachyon. Part B: Some

Science.gov (United States)

Progress in four research areas on this project are summarized under the following topics: (1) Geminate charge pair recombination in hexane; (2) Fast current measurements resulting from excitation of charge transfer (CT) states; (3) Measurement of the dipole moment of excited states by DC conductivity; and (4) Charge separation at macroscopic interfaces between electron donor and acceptor solids. In a final section, personnel who have contributed to the project during the past budget period are described.

CERN Document Server

The top-color assisted technicolor (TC2) mode predicts the existence of a pair of charged top-pions $\\pi^{\\pm}_t$. In this paper, we study the production of the charged top-pions pair $\\pi^{\\pm}_t$ at next generation $\\gamma\\gamma$ colliders. The results show that the production rates can reach the level of $10^2$ fb with reasonable parameter space. With a large number of events and the clean background, the charged top-pion should be observable at the $\\gamma\\gamma$ colliders. Therefore, our studies can help us to search for charged top-pion, and furthermore, to test the TC2 model.

CERN Document Server

We provide a quantitative assessment of the probability distribution function of the concentration parameter of galaxy clusters. We do so by using the probability distribution function of halo formation times, calculated by means of the excursion set formalism, and a formation redshift-concentration scaling derived from results of N-body simulations. Our results suggest that the observed high concentrations of several clusters are quite unlikely in the standard Lambda CDM cosmological model, but that due to various inherent uncertainties, the statistical range of the predicted distribution may be significantly wider than commonly acknowledged. In addition, the probability distribution function of the Einstein radius of A1689 is evaluated, confirming that the observed value of ~45" +/- 5" is very improbable in the currently favoured cosmological model. If, however, a variance of ~20% in the theoretically predicted value of the virial radius is ...

CERN Document Server

We address the deviations of the scaling relations of elliptical galaxies from the expectations based on the virial theorem and homology, including the "tilt" of the "fundamental plane" and the steep decline of density with mass. We show that such tilts result from dissipative major mergers once the gas fraction available for dissipation declines with progenitor mass, and derive the scaling properties of the progenitors. We use hydrodynamical simulations to quantify the effects of major mergers with different gas fractions on the structural properties of galaxies. The tilts are driven by the differential shrinkage of the effective stellar radius as a function of dissipation in the merger, while the correlated smaller enhancements in internal velocity and stellar mass keep the slope of the velocity-stellar mass relation near V \\pr M_*^{1/4}. The progenitors match a straightforward model of disc formation in LCDM haloes. Their total to stellar mass ratio within the ...

International Nuclear Information System (INIS)

We present the design, analysis, and results of the high brightness electron beam experiments currently under investigation at Sandia National Laboratories. The anticipated beam parameters are the following: energy 12 MeV, current 35 endash 40 kA, rms radius 0.5 mm, and pulse duration 40 ns full width at half-maximum. The accelerator is SABRE, a pulsed linear inductive voltage adder modified to higher impedance, and the electron source is a magnetically immersed foilless electron diode. 20 endash 30 T solenoidal magnets are required to insulate the diode and contain the beam to its extremely small-sized (1 mm) envelope. These experiments are designed to push the technology to produce the highest possible electron current in a submillimeter radius beam. Design, numerical simulations, and experimental results are presented. copyright 1997 American Institute of Physics.

Energy Technology Data Exchange (ETDEWEB)

The plastic deformation behavior of formed CICC for the superconducting Tokamac fusion device was examined and appropriate manufacturing information was provided. A relation between travel of the bending roller and spring back displacement was obtained via virtual manufacturing. The radius of CICC after forming was expressed as a function of the bend-roll travel. The maximum von Mises stress after spring back was also monitored for the SAGBO prediction. Next, the variation of the CICC cross-sectional area was examined during the first turn and during conduit bending with the largest curvature. Finally, the coil radius was measured and compared with the data generated from the virtual manufacturing. The measured data showed similar pattern as predicted one. Using the mapping function found to match with the real data, the data from the virtual manufacturing may facilitate accurate manufacturing.

International Nuclear Information System (INIS)

The intercalation reaction of some layered transition metal disulfides with alkali metals, alkali metal hydroxides, and tetraalkylammonium hydroxides were investigated. The alkali metal intercalates were prepared in the respective metal-hexamethylphosphoric triamide solutions in vaccuo, and the hydroxide intercalates in aqueous hydroxide solutions. According to the intercalation reaction, the c-lattice parameter was increased, and the increase indicated the expansion of the interlayer distance. In the case of alkali metal intercalates, the expansion of the interlayer distance increased continuously, corresponding to the atomic radius of the alkali metal. On the other hand, the hydroxide intercalates showed discrete expansion corresponding to the effective ionic radius of the intercalated cation. All intercalates of TaS_2 amd NbS_2 were superconductors. The expansion of the interlayer distance tended to increase the superconducting transition ...

Science.gov (United States)

We consider a unified model of Fe ion acceleration in the solar corona. The model comprises charge-changing processes, Coulomb energy losses, and both regular and stochastic acceleration. At a given acceleration scenario, the type of acceleration is found to have a minor effect on the mean charge states, but the shapes of the charge-state distributions produced by regular acceleration and by stochastic acceleration are different. During a continual acceleration at coronal temperatures, iron ions typically follow rising trajectories on the charge-energy plane. These trajectories are situated below the mean equilibrium charge curve defined from the balance of ionization and recombination at fixed energy. During stopping, the iron ions cross the equilibrium charge curve and run through a series of charge states above the mean equilibrium ...

Energy Technology Data Exchange (ETDEWEB)

Picosecond charge-collection transients measured for GaAs/AlGaAs HBTs following 3.0 MeV [alpha]-particle and 620 nm picosecond laser excitation reveal charge-collection efficiencies up to twenty-eight times smaller than for GaAs MESFETs, with [approximately]90% of the charge collected within 75 ps of the ionizing event. The small charge-collection efficiency of the HBTs is a consequence of the ultrafast charge-collection dynamics in these devices. The authors show that picosecond laser excitation reproduces nicely the ion-induced transients, providing a valuable tool for the investigation of charge-collection and SEU phenomena in these devices.

Energy Technology Data Exchange (ETDEWEB)

We report the use of ion beam induced charge imaging to characterise the charge signal uniformity of epitaxial gallium nitride radiation detectors. The detectors were fabricated from 2 {mu}m thick semi-insulating gallium nitride, grown by MOCVD on a sapphire substrate. A carrier concentration of 1.4x10{sup 15} cm{sup -3} was measured using capacitance-voltage measurements. Ion beam induced charge imaging was carried out with a 2 MeV alpha particle beam focussed to a 3 {mu}m diameter and raster scanned across the device. The resulting ion beam images show excellent charge signal uniformity in this material with no evidence of material defects or polycrystalline structure on the micrometer length scale. No evidence of charge signal trapping was observed in these devices.

Energy Technology Data Exchange (ETDEWEB)

Using the Relativistic Mean Field Theory (RMF) it is shown that different proton fraction which is directly connected with the neutron excess and with the asymmetry of the system affects proto-neutron stars parameters and changes their composition. The obtained form of the equation of state allows to construct the mass-radius relations and shows that the increasing asymmetry creates more compact stars. The inclusion of {delta} meson together with nonlinear vector meson interaction terms and magnetic field make this effect even stronger.

Energy Technology Data Exchange (ETDEWEB)

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.).

Energy Technology Data Exchange (ETDEWEB)

The interest in efficient solar collector design has stimulated investigation of two-dimensional (trough-like) cavity structures. A novel principle for designing cavity enclosures is described. The present method maintains high transmission albeit at the expense of some concentration in the presence of gaps as large as the radius between reflector and receiver. The new method can be applied to advantage to nonimaging concentrator design as well as to line focus concentrators.

International Nuclear Information System (INIS)

We study the dynamical evolution of globular clusters containing primordial binaries, including full single and binary stellar evolution using our Monte Carlo cluster evolution code updated with an adaptation of the single and binary stellar evolution codes SSE and BSE from Hurley et al. We describe the modifications that we have made to the code. We present several test calculations and comparisons with existing studies to illustrate the validity of the code. We show that our code finds very good agreement with direct N-body simulations including primordial binaries and stellar evolution. We find significant differences in the evolution of the global properties of the simulated clusters using stellar evolution compared with simulations without any stellar evolution. In particular, we find that the mass loss from the stellar evolution acts as a significant energy production channel simply by reducing the total gravitational binding energy and can significantly prolong the initial core ...

Energy Technology Data Exchange (ETDEWEB)

Transonic flows with heat addition due to condensation are important to many technical applications, e.g. to the last stages of large steam turbines, where nucleation and droplet formation become important. Our current research concentrates on the interaction of vortex shedding with condensation in turbines and on rotor/stator interaction in nucleating flows. Both phenomena lead to a significant change of the condensate mass and the droplet radius distribution in the downstream two-phase flow regime. (orig.)

International Nuclear Information System (INIS)

The IGC-30 HPGe detector with MCA 'CANBERRA-10 PLUS' allows to determine surface contamination of areas of any type with a minimum error in radius 8-10 m, at a 'uniform' contamination. A modification of the CANBERRA hardware and software is described allowing determination of both the activity of a possible 'radioactive spot' and the activity of the whole observed surface. (author).

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 ...

Energy Technology Data Exchange (ETDEWEB)

We present a set of exact solutions for quantum Bianchi type-IX anisotropic cosmological models (including the Taub model) of the form {Psi}={ital We}{sup {minus}{ital S}}. These solutions are spread over all values of anisotropy near the singularity, but at larger values of the radius of the universe they are strongly peaked around the {ital k}=+1 Friedmann-Robertson-Walker model.

UK PubMed Central (United Kingdom)

Using QCT, we made a longitudinal, population-based assessment of rates of bone loss over life at the distal radius, distal tibia, and lumbar spine. Cortical bone loss began in perimenopause in women...Full Text Available

International Nuclear Information System (INIS)

The measured result of charged multiplicity in cosmic-ray proton induced nuclear reaction from Chinese satellite emulsion is reported. The correlation of shower and heavy particles is discussed and compared with p-emulsion interactions.

Energy Technology Data Exchange (ETDEWEB)

Electric cars can be recharged via charging stations, battery exchange, or induction cable lanes in asphalted roads. The users' wishes remain unexplored, so a number of technologies are competing in this sector.

Science.gov (United States)

Charge flow and valence/d-band behavior in ion-beam-mixed (IBM) Pd1-xAgx (x = 0.5-0.9) alloys have been studied by X-ray photoemission measurement of the valence bands and of core-level binding energy shifts and X-ray absorption near-edge structure. We correlated the observed Ag 3d5/2 core-level shifts in these IBM alloys, relative to the elemental Ag, with the White Line area changes at the Pd and Ag L3-edge to investigate the charge redistribution at the Ag site. The results indicate that there is a decrease in sp-like conduction electron and a negligible change in the number of d-electrons at the Ag site upon alloying. These results are in line with our previous results in which Pd gains d-charges and loses sp-type charges. This electron redistribution due to hybridization in the alloy leads small net charge transfer from the Ag site to the Pd site in accordance with ...

Science.gov (United States)

... small water or ice particles by impaction ... flight recording; principally the hydrometeor charge unit ... capability of directing aircraft movements by radio ...

Energy Technology Data Exchange (ETDEWEB)

Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)

Energy Technology Data Exchange (ETDEWEB)

The purpose of this document is to describe the NIF Project Organization and the roles and responsibilities of the managers charged with executing the Project.

Science.gov (United States)

... The task consisted of determination of the most economical composition of the charge of the cupola furnace of the foundry. 21s was no simple task. ...

International Nuclear Information System (INIS)

(May 1974). United Kingdom Hemp, J. Oxford Univ. (UK). Dept. of

International Nuclear Information System (INIS)

We review recent progress on experimental studies of collective charge excitations in hole-doped spin ladder system Sr_1_4_-_xCa_xCu_2_4O_4_1, focusing on anomalous features of phase excitation. We also discuss possible candidates for related charge ordered state, together with a controversial issue of the hole density transferred from spin chain layers to spin ladder layers. (author)

CERN Document Server

Motivated by recent anomalous CDF data on $Wjj$ events, we study a possible explanation within the framework of the two-Higgs doublet model. We find that a charged Higgs boson of mass $\\sim$ 140 GeV with appropriate couplings can account for the observed excess. In addition, we consider the flavor-changing neutral current effects induced at loop level by the charged Higgs boson on the $B$ meson system to further constrain the model. Our study shows that the like-sign charge asymmetry $A_{s\\ell}^b$ can be of ${\\cal O}(10^{-3})$ in this scenario.

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} The use of resonant photoemission in its 'core-hole clock' expression for the study of the dynamical charge transfer across hybrid organic-inorganic interfaces and for the intermolecular charge transfer in the bulk of organic thin films is reviewed. {yields} The electronic coupling to the substrate and the efficiency of charge transport across hybrid interfaces is different for individual electronic subsystems of the molecular adsorbate. {yields} The intermolecular charge transfer in the bulk of discotic liquid crystals occurs on the order of a few femtoseconds and is faster than expected from the macroscopic charge transport characteristics of the material. -- Abstract: The focus of this brief review is the use of resonant photoemission in its 'core-hole clock' expression for the study of two important problems ...

Energy Technology Data Exchange (ETDEWEB)

A generic insensitive fuze train to initiate insensitive high explosives, such as PBXW-124. The insensitive fuze train uses a slapper foil to initiate sub-gram quantities of an explosive, such as HNS-IV or PETN. This small amount of explosive drives a larger metal slapper onto a booster charge of an insensitive explosive, such as UF-TATB. The booster charge initiates a larger charge of an explosive, such as LX-17, which in turn, initiates the insensitive high explosive, such as PBXW-124.

Energy Technology Data Exchange (ETDEWEB)

This paper mainly deals with the charging processes of a cylindrical heat storage capsule filled with stearic acid, sliced paraffin and lauric acid as phase-change materials (PCMs). Experimental results demonstrate that, compared to the capsule with a single PCM, the charging rate of the capsule employing three PCMs is enhanced obviously. (author)

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the charging mode of an in-series assembly of lithium-carbon battery cells, a test has been performed on 5 commercial cells (18650) of 0.95 Ah nominal capacity. Results show that it is possible to cycle the cells at 80% of their output capacities during more than 2000 cycles. The management of the battery consists in maintaining a constant battery voltage as soon as a cell reaches its limit voltage during constant current charging. The initial dispersion of cells has been maintained practically constant during the cycling and the charge state of all cells has decreased progressively. (J.S.)

International Nuclear Information System (INIS)

Cluster calculations of the electronic structure and charge distribution in V_3Si have been performed using two different molecular orbital methods: a semiempirical LCAO and the MS X#alpha# model. The results are compared with X-ray emission spectra and band structure calculations. An analysis of the calculated electronic distribution reveals a charge transfer from Si-atoms to V-atoms, the additional charge on a V-atom being 0.6e (LCAO) and 0.4e (MS X#alpha# method). The results are in good agreement with experiment, which indicates that the cluster approach is adequate for the description of charge distributions and spectra characteristics of the A-15 compounds. (author).

Energy Technology Data Exchange (ETDEWEB)

A mathematical model has been constructed to describe the creation and filling of thermoluminescence traps during irradiation. Processes considered include trap filling, recombinations both between free charges and between free and trapped charges and thermal de-trapping. Also a simple trap creation term, linear with dose, has been included. A computer program has been written in order to solve the system of differential equations describing the various charge carrier flows during irradiation. The model and the program are described and the results of the application of the model to some simple energy-level schemes are discussed. Thermal de-trapping and band-to-band recombinations can introduce a dose rate dependence into the accumulation of trapped charge, whilst trap creation leads to the supralinear growth of charge trapped at certain defects with increasing dose.

International Nuclear Information System (INIS)

The energy deposited by the passage of a single, energetic, heavy-ion through a semiconductor produces dense electron-hole (eh) pair concentrations near the ion trajectory. The size, shape, and charge density of an ion track represent critical parameters for many models of single event phenomena. The authors describe the design and uses of possible semiconductor test structures for measuring the initial radial distribution of charge and subsequent charge transport in a high energy, heavy-ion track. Numerical simulations show how the test structure can resolve different radial distributions of charge within an ion track. The test structure simulations also show the importance of accurately representing ion track structure in single event effects simulations.

International Nuclear Information System (INIS)

UBVRI CCD surface photometry and color gradients are presented for 10 central dominant galaxies (CDGs), comprising gE, D, and cD morphological types and covering the range of Bautz-Morgan cluster types. The mean magnitude of the color gradients to a radius of 20 kpc is in agreement with those found in recent CCD studies of bright ellipticals in Virgo. The size of the gradients are consistent with N-body model predictions in which these galaxies are formed or enhanced by merger events. Parameters such as ellipticity, position angle of the major axis, and deviation from ellipticity for eight single-nucleus CDGs are also given. All galaxies show large changes in ellipticity and position angle with radius, and can be considered similar to Kormendy's T3 class of galaxies, in which tidal effects on isophotal structure are very probable. Three out of eight single-nucleus CDGs, NGC 1399, NGC 6876 and IC 1860, show evidence of isochromal flattening ...

International Nuclear Information System (INIS)

Seeing convolved two-dimensional de Vaucouleurs profiles have been fitted to digital images of the brightest elliptical galaxies in two nearby groups of galaxies and three clusters of galaxies with redshifts in the range 0.06 to 0.15. The digital images were created by scanning electronographic plates obtained by the use of several versions of the RGO electronographic camera. The linear relation between effective surface brightness #mu#/sub e/ and the logarithm of the effective radius r/sub e/, first discovered by Kormendy to be valid for nearby elliptical galaxies, is found to be equally valid for the largest and brightest galaxies in rich clusters of galaxies. The apparent universal nature of that relation indicates that the same type of processes might have been involved during the formation of all ellipticals from cD galaxies in clusters to fainter ellipticals in small groups. It is suggested that the (I/sub e/,r/sub e/) relation is not changed by the expected ...

International Nuclear Information System (INIS)

A new foilless diode with a non-magnetically immersed cathode was recently designed and built for the Sandia Recirculating Linear Accelerator (RLA). Because there is also no radial component of electric field at the cathode, the electron beam starts almost parallel and is matched to a solenoidal transport system with minimum increase in divergence and radius. The electrode emission surface is specified by an area covered with felt which undergoes explosive electron emission at low electrical field stresses (60 kV/cm). The 1.7 MV, 4.8-kA produced beam is transported 1.5 meters to the injection region of the racetrack via a system of solenoids and focusing coils. The maximum transverse velocity component at injection point (1.5 m downstream from the cathode surface) is #beta# perpendicular = 0.03 and the radius r = 2.8 cm which give a quite small beam emittance #epsilon# = 0.08 rad-cm. Three- dimensional numerical simulations suggest that ...

CERN Document Server

We present results from an investigation of the dynamical behavior of buoyant magnetic flux rings in the radiative interior of a uniformly rotating early-type star. Our physical model describes a thin, axisymmetric, toroidal flux tube that is released from the outer boundary of the convective core, and is acted upon by buoyant, centrifugal, Coriolis, magnetic tension, and aerodynamic drag forces. We find that rings emitted in the equatorial plane can attain a stationary equilibrium state that is stable with respect to small displacements in radius, but is unstable when perturbed in the meridional direction. Rings emitted at other latitudes travel toward the surface along trajectories that largely parallel the rotation axis of the star. Over much of the ascent, the instantaneous rise speed is determined by the rate of heating by the absorption of radiation that diffuses into the tube from the external medium. Since the time scale for this heating varies like the ...

Science.gov (United States)

To estimate of the dispersion trend of 3H and 14C discharged from the Wolsung Nuclear Power Plants, the present level of 3H and 14C in environmental samples in the vicinity of the Wolsong site was studied. Tree-ring cellulose analyses were carried out for retrospective evaluation of 3H and 14C in the environment around the Wolsong Nuclear Power Plants. 3H released from the Wolsong Nuclear Power Plants has affected an area up to a 25-km radius from the site, while almost all 14C was deposited within a 2-km radius, reaching to a natural level over 2 km. Organically bound tritium concentrations in tree rings were strongly correlated with the gaseous tritium discharge rate, while delta14C (excess) in tree rings ranged from 204 per thousand to 460 per thousand, which did not significantly vary with year. PMID:10832930

Science.gov (United States)

For the estimation of the dispersion trend of tritium discharged from the Wolsung nuclear power plant, the present level of tritium in environmental samples in the vicinity of the Wolsong site has been studied. On the basis of tritium concentrations in environmental samples, the effective dose due to tritium has been estimated for an individual and population within a 16 km radius from the Wolsong site. The annual effective dose of tritium to an inhabitant around the Wolsong site ranged from 0.15 microSv y-1 to 1.3 microSv y-1. The dose level was negligible and much lower than some applicable standards, i.e. the limit on exposure from nuclear fuel cycle to the general public as recommended by ICRP (1 mSv y-1) or US EPA's limit (0.25 mSv y-1). The collective dose to the total population within a 16 km radius from the site, 1.2 x 10(-2) man.Sv y-1 was much lower than 1 man.Sv y-1, an applicable criterion for the so-called "exemption" of radiation ...

Energy Technology Data Exchange (ETDEWEB)

A design of the modular coil system for CHS-qa has been made for the plasma configuration '2b32' with the aspect ratio 3.2. The magnetic field strength and the major radius are 1.5 T and 1.5 m, respectively. The normal component of magnetic field produced by the modular coils is minimized on the plasma boundary to obtain the optimum coil design. We put engineering constraint on the distance between adjacent modular coils and the radius of coil curvature. The dependence of the residual normal component of the field on these conditions is examined, and the realistic values for them are selected. Additional coils to control various properties of the magnetic field configuration (the rotational transform, the magnetic well depth, etc.) have been designed and a flexibility of the magnetic field configuration is realized. For the case that the rotational transform crosses the low-order rational value resulting in magnetic islands, ...

CERN Document Server

The bright star 55 Cancri is known to host five planets, including a transiting super-Earth. The interferometric study presented here yields directly determined values for 55 Cnc's stellar astrophyiscal parameters: $R=0.943 \\pm 0.010 R_{\\odot}$, $T_{\\rm EFF} = 5196 \\pm 24$ K. We use isochrone fitting to determine 55 Cnc's age to be 10.2 $\\pm$ 2.5 Gyr, implying a stellar mass of $0.905 \\pm 0.015 M_{\\odot}$. Our analysis of the location and extent of the system's habitable zone (0.67--1.32 AU) shows that planet f ($M \\sin i = 0.155 M_{Jupiter}$) spends the majority of the duration of its elliptical orbit in the circumstellar habitable zone, where, with moderate greenhouse heating, it could harbor liquid water. Finally, our direct value for 55 Cancri's stellar radius allows for a model-independent calculation of the physical diameter of the transiting super-Earth 55 Cnc e ($\\sim 2.05 \\pm 0.15 R_{\\earth}$), which, depending on the planetary mass assumed, ...

British Library Electronic Table of Contents (United Kingdom)

The details of pulsating stochastic flows accompanying the interaction of a microwave filament (regarded as a heated rarefied channel) and an aerodynamic body in supersonic flow are examined numerically using the Euler equations. Symmetrical and asymmetrical filament locations relative to the aerodynamic body are considered. The flowfields are characterized by large scale pulsations and small scale stochastic fluctuations. The mechanisms of the formation of these flow structures are discussed. Two qualitatively different kinds of flowfields are observed depending on the magnitude of the filament radius, with domination of the pulsations of flow parameters or stochastic phenomena. Flow instabilities inherent to the problems under interest are described. The problems are considered in both p...

Energy Technology Data Exchange (ETDEWEB)

The signature of the negative snakes from the soft X-ray cameras is very similar to the more usual snakes except that the localised region of the snake has, compared with its surroundings, decreased rather than increased emission. Circumstances where negative snakes have been seen are reviewed. The negative snake appears as a region of increased resistance and of increased impurity density. The relationship between the shear and the current perturbation is shown, and it seem probable that the magnetic shear is reversed at the point of the negative snake, i.e. that q is decreasing with radius. 6 refs., 6 figs.

Energy Technology Data Exchange (ETDEWEB)

Measurements of the expansion rate of pure-electron plasmas have been performed on the Electron Diffusion Gauge (EDG) device at background helium gas pressures in the 5 x 10(superscript -8) Torr to 1 x 10(superscript -5) Torr range, where plasma expansion due to electron-neutral collisions dominates over plasma expansion due to trap asymmetries. It is found that the expansion rate, defined as the time rate of change of the particles' mean-square radius, scales approximately linearly with pressure and inversely as the square of the magnetic field strength in this regime, in agreement with classical predictions.

International Nuclear Information System (INIS)

A study of the #pi#1g/sub 9/2/ orbit size in "8"8Sr, "9"0Zr, and "9"2Mo is presented. The rms radius for the point-proton density is extracted by studying transitions to 8"+ states in these nuclei. The radii are consistently larger than a value determined in a magnetic electron scattering experiment on "9"3Nb. A qualitative discussion of the ground state occupation of the #pi#1g/sub 9/2/ orbit based on the transition amplitudes to the 8"+ states is given.

Science.gov (United States)

Long cylindrical mirror sections with an 'Alliptical' cross- section and an interfoci distance of approximately 1 m can be produced by means of diamond fly cutting. However, because of the finite tool radius, the generated profile is basically not an ellipse, but an equidistant ellipse or 'Allipse'. By numerical ray tracing analysis two unique conjugated 'A-points' can be found that are optically nearly equivalent with pure elliptical focal points. A reversed modeling procedure is used to predict the optimum machine configuration for producing just the required ellipse sections. Optical figure quality, focal line position and straightness are tested by a simple deflectometer set-up.

Science.gov (United States)

Using near-field optical microscopy, the authors investigate propagation of channel plasmon polaritons excited in the wavelength range of 1425-1640 nm along smoothly bent and split V-shaped grooves milled in a gold film. We find that for 0.6-?m-wide and 1.1-?m-deep grooves bent with the smallest curvature radius of ?0.83 ?m, the double bend (for S bends) and splitting (for Y splitters) losses decrease for longer wavelengths approaching (in the wavelength range of 1600-1640 nm) the levels of ~0 and 0.5 dB, respectively.

Energy Technology Data Exchange (ETDEWEB)

The present analysis shows that the observed efficiency of current drive with synergy between LHCD and ICRH is in good agreement with the relativistic theory of Karney and Fisch for Landau damped waves. The predicted power absorption from the fast wave by the electron tail is within 30% of the measured value. In the presence of significant fast electron diffusion within a slowing down time it would be possible to produce central current drive using multiple ICRF resonances even when the LHCD deposition is at half radius, as in an ITER type device. (authors). 4 refs., 6 figs.

International Nuclear Information System (INIS)

This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed ...

Energy Technology Data Exchange (ETDEWEB)

The general usefulness of neutron activation analysis (NAA) for samples containing the platinum group elements and Au, either as major or trace constituents, is discussed. Charged particle activation is shown to be a viable or complementary alternative. Proton (6-10 MeV) and alpha particle (9-15 MeV) beams, produced in a Tandem van de Graaff accelerator, have been established to be the most effective choice. By taking advantage of the Coulomb barrier effect and the fact that many charged particle induced reactions have relatively large threshold values, the same instrumental technique can be applied, with minor modifications, to a wide range of materials.

Energy Technology Data Exchange (ETDEWEB)

Doubly-excited 2s{sup -1}2p{sup -1}3pnp autoionizing resonance series of Ne atom as well as autoionizing resonances in the 2s region of Na and Mg atoms have been studied with monochromatized synchrotron radiation. Use of charge-separated photoion-yield method allowed us to detect these weak resonances in a clarified way in the yield curves of doubly-charged ions. The observed resonance states have been interpreted with the help of MCDF calculations, and the decay processes of these resonance states are discussed briefly.

Energy Technology Data Exchange (ETDEWEB)

The proton momentum distributions of (39)K,(40)Ca and (48)Ca are calculated from the model-independent charge distributions obtained from analyses of electron elastic scattering and muonic atoms, and also from the charge distributions calculated from the single-particle potential method in the framework of the flucton model. The sensitivities of the momentum distribution to different regions of the charge distribution are determined. The analysis is extended to the neutron distributions using the single-particle potential method, and the differences between the proton and neutron momentum distributions are examined. The resulting momentum distribution in the case of (40)Ca is used for analyzing the quasielastic electron scattering.

International Nuclear Information System (INIS)

Energy conservation and local energy deposition are investigated in the context of coupled-particle (i.e., neutrons, gamma rays, and charged particles) transport analysis. For charged particles, the concept of group splitting the 1 = 0 transfer matrix to ensure both particle and energy conservation is introduced. Although these procedures are more complex than those found in the usual neutron or coupled-neutron gamma-ray problem, they yield a consistent approach for the calculation of local energy deposition.

CERN Document Server

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of a baryon charge diffusion in rapidity space. Evidently, such a diffusion should decrease the baryon charge in the fragmentation region leading to the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. We present the quantitative predictions for the Feynman scaling violation at LHC energies and even at highier energies that can be important for cosmic ray physics.

Energy Technology Data Exchange (ETDEWEB)

The velocity distribution of electrons ejected close to the forward direction by 0.8-2 MeV/A ions traversing various solid targets, including a Au monocrystal, is measured in coincidence with emerging charge-selected ions. The velocity spectrum is observed to be independent of outgoing projectile velocity and charge state for polycrystalline targets. Measurements on the Au crystal under channeling conditions show dependences on final charge state, and are tentatively explained by assuming that the main contribution to the production yield comes from the non-channeled fraction of the ions. A simple model for the creation of the forward-ejected electrons is proposed, which accounts for most of the experimental findings.

International Nuclear Information System (INIS)

The charge distribution in the alpha particle induced fission of "2"0"9Bi has been studied at alpha particle energy of 55.7 MeV and 58.6 MeV. The fractional cumulative yields of "9"7Zr, "9"9Mo, "1"0"1Mo and "1"1"2Pd have been determined using gamma ray spectrometry. The charge distribution have been found to be broad. (author). 4 refs., 1 ta b.

International Nuclear Information System (INIS)

A new potential function based on spectroscopic results for diatomic molecules is presented and applied to the hydrogen bonding systems. The potential energy of interaction is supposed to have electrostatic, polarization, dispersion, repulsion and effective charge-transfer contributions. Estimates of the effective charge-transfer quantity have been made based on the average charge of the proton donor and the acceptor atoms. For dimers such as water, methanol, acetic acid and formic acid, the vibrational stretching frequencies and dimerization energies are calculated and discussed in connection with Badger-Bauer rule. (author).

Science.gov (United States)

... the Park Services Colorado Canyons National Conservation Area (CCNA)....

CERN Document Server

Monopolar charge disorder effects are studied in the context of fluctuation-induced interactions between neutral dielectric slabs. It is shown that quenched bulk charge disorder gives rise to an additive contribution to the net interaction force which decays as the inverse distance between dielectric surfaces. This effect may thus completely mask the standard Casimir--van der Waals effect. By contrast, annealed (bulk or surface) charge disorder leads to a net interaction force whose large-distance behavior coincides with the universal Casimir force between perfect conductors, which scales as inverse cubic distance, and the dielectric properties enter only in subleading corrections.

Science.gov (United States)

... detonation velocity of single base and double base propellants is investigated using two types ofignititor; an exploding bridgewire detonator with C4 ...

Science.gov (United States)

... MPS) Advanced Liquid Crystalline Optical Materials Superconductivity Computation and Visualization ... Cement-Based Materials Synthesis, Growth, and Analysis of Electronic Materials Photoinduced Charge ...

International Nuclear Information System (INIS)

German (15 Jun 1974). Switzerland Kocian, P. Ecole Polytechnique Federale,

Science.gov (United States)

Page 1. USAFSAM-TR-89-1 AD-A221 893 ... Dr. Johnathan L. Kiel (USAFSAM/RZP) was the Laboratory Project Scientist-in-Charge. ...

Science.gov (United States)

... An explosive charge (exploding bridgewire (EBW) detonator) was used for the crosshole P-wave tests. For the crosshole S-wave tests a ...

Energy Technology Data Exchange (ETDEWEB)

Electrostatic beneficiation of dry coal has received significant attention in the last decade. In this process the coal is ground and then charged, either by corona charging or by triboelectrification (friction charging). Coal and minerals receive different levels of charge -- often opposite polarities in the case of triboelectrification -- and can then be separated based on differences in electrical mobility. Problems associated with the techniques include rapid deposition of particles on the electrodes, thus, effecting further separation. The goal of this project is to optimize the electrostatic coal cleaning process to remove pyrites and inorganic materials through studies of the electrostatic properties of powdered coal, in-situ measurements of the electrodynamics of coal and mineral particles inside the separator, and development of self-cleaning collector plates for continuous separation.

Science.gov (United States)

Electron charge distributions are presented for Nb3Ge, Nb3Al, and two hypothetical A-15 structures. Results indicate that the bonding in these materials is mainly metallic in character with some covalentlike bonding between Nb-chain atoms. We find significant coupling between neighboring chains and also between chain atoms and atoms at the cubic site. Comparison is made with various theoretical models. Investigation of the charge character of states near EF suggests further developments in current theories on the structural transformation of A-15 compounds. The effect of chain dimerization on electronic states and charge distribution of Nb3Ge is also investigated.

International Nuclear Information System (INIS)

(1976). USSR Lupin, VM Ramazanov, PE Tomskij Gosudarstvennyj Univ.

International Nuclear Information System (INIS)

Measurements of absolute differential cross sections for H"+-H_2 direct, single-, and double-charge-transfer scattering at 0.5, 1.5, and 5.0 keV are reported at laboratory scattering angles less than 1 degree with an angular resolution of approximately 0.02 degree. The cross sections exhibit deep interference oscillations in single-charge-transfer scattering, but no such oscillations are present in direct and double-charge-transfer scattering. Theoretical cross sections derived using the diatoms-in-molecules method to describe the molecular states in a semiclassical molecular-orbital three-state close-coupling model within a semiclassical framework agree satisfactorily with the experimental results.

Energy Technology Data Exchange (ETDEWEB)

Electric cars are as unpopular as ever, but the hopes for environmentally sound, quiet vehicles may lie, surprisingly, with the commercial market. Advances in electric vans and lorries are reviewed. (author).

Energy Technology Data Exchange (ETDEWEB)

Mass shift of accelerated charges-sources of a massive vector and massive scalar fields, are considered in an approximation which is classical with respect to the charge motion but quantum with respect to their interaction with their proper field. For uniformly accelerated charges the mass shifts are expressed in terms of cylindrical functions of the quantum parameter ..mu..c/sup 3//h/2..pi..w/sub 0/ which is the ratio of the mass ..mu.. of the proper field quanta to the charge acceleration w/sub 0/. For finite positive values of the parameter both the imaginary and real parts of the shifts are nonvanishing and negative. For ..mu -->..0 the real part of the mass shift of a vector charge tends to the classical value -..cap alpha..h/2..pi..w/sub 0//2c/sup 3/ obtained earlier, thereas that of the scalar charge tends to zero. These and other properties of the ...

International Nuclear Information System (INIS)

... brakes reactor charging machines reactors machine parts Int. Cl. B66d5/00;

Science.gov (United States)

Photoinduced charge separation reactions form the basis for energy storage processes in both natural and artificial photosynthesis. Moreover, rapid reversible photoinduced electron transfer reactions are a class of photophysical phenomena that can be exploited to develop schemes for optical switching. Examples from each of these fields are discussed.

International Nuclear Information System (INIS)

A new formulation of the theory of tachyons is developed using the same two postulates as in special relativity. Use is made of a 'switching principle' to show how tachyons automatically obey the laws of conservation of energy, momentum and electric charge. Tachyonic mechanics is further developed by a consideration of tachyonic rods and clocks. There follows a discussion of the conservation of electric charge and the apparent visual appearance of a tachyonic cube. 19 refs., 9 figs.

Energy Technology Data Exchange (ETDEWEB)

There are 13 Electron Beam Ion Sources in operation which produce highly charged ions, up to Th{sup 80+} and Xe{sup 53+}. Most of the sources are used to study these ions under electron impact or when recombining with gaseous or solid targets. That provides an insight into the atomic physics of these highly charged ions and into the physics of the plasma in which such ions can be found. This paper reviews the present knowledge of atomic processes, important in the production of such ions with an EBIS.

Energy Technology Data Exchange (ETDEWEB)

It is shown that a cosmic gamma-ray telescope made of a multilayer silicon tracker and a imaging CsI calorimeter, is capable of identifying cosmic ray nuclei. The telescope charge resolution is estimated around 4% independently of charge. Simulation methods are used to determine the telescope properties for nuclei detection.

Energy Technology Data Exchange (ETDEWEB)

The amplitudes for the pion-nucleon charge exchange reaction of the Karlsruhe-Helsinki and the George-Washington-University partial-wave analyses are compared with those of a Regge-cut model with the aim to explore the possibility to provide high-energy constraints for theoretical baryon resonance analyses in the energy region above 2 GeV. (orig.)

International Nuclear Information System (INIS)

The distribution of mass, charge and angular momentum transfer among the products of 54-Fe (255 MeV) ions collisions with the 106 Cd target have been studied. The energy level schemes for 92-Mo, 60-Ni, 96-Ru and 56-Fe are presented. The production yields of different isotopes were also measured. 1 ref., 14 figs.

British Library Electronic Table of Contents (United Kingdom)

We study the influence of Sr substitutions on the structural counterpart of the MI transition of Formula Not Shown . When Sr content increases, the commensurate CDW modulation of pure Formula Not Shown is changed into an incommensurate short range modulation that we attribute to a charge ordering of the Formula Not Shown electrons. The same features are observed in S deficient samples.

International Nuclear Information System (INIS)

We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the one of the top quark, at future Linear Colliders operating in #gamma##gamma# mode at the TeV energy scale. Final states with one or two H"#+-# bosons are considered, as produced by both tree- and loop-level interactions. (orig.)

International Nuclear Information System (INIS)

The original purpose of this research was an investigation into the use of slow space charge waves on weakly relativistic electron beams for ion acceleration. The work had three main objectives namely, the development of a suitable ion injector, the growth and study of the properties of slow space charge waves on an electron beam, and a combination of the two components parts into a suitable proof of principle demonstration of the wave accelerator. This work focusses on the first two of these objectives.

CERN Document Server

Koide's mass formula is an empirical relation among the charged lepton masses which holds with a striking precision. We present a model of charged lepton sector based on U(3)\\times SU(2) family gauge symmetry, which predicts Koide's formula within the present experimental accuracy. Radiative corrections as well as other corrections to Koide's mass formula are kept under control. We adopt a known mechanism, through which the charged lepton spectrum is determined by the vacuum expectation value of a 9-component scalar field \\Phi. On the basis of this mechanism, we implement the following mechanisms into our model: (1) The radiative correction induced by family gauge interaction cancels the QED radiative correction to Koide's mass formula, assuming a scenario in which the U(3) family gauge symmetry and SU(2)_L weak gauge symmetry are unified at 10^2-10^3 TeV scale; (2) A simple potential of \\Phi invariant under U(3)\\times ...

International Nuclear Information System (INIS)

The Jodrell Bank MERLIN array was used to map the OH 1665-and 1667-MHz masers in the circumstellar envelope of U Orionis in 1984, 1986 and 1987. The OH masers lie within a region of extent 130 x 180 AU"2, and have complex distribtuions which are different for each line and polarization. The masers show clumpy structures with a typical clump size of #approx# 25 AU. The strongest emission is from a ring of radius 60 AU which we interpret as part of an expanding, tilted torus. Proper motions have been measured for the OH masers on the ring. The ring has a proper motion of 5.4#+-#1.4 mass yr"-"1 corresponding to a transverse expansion velocity of #approx# 7 km s"-"1 for the period-luminosity distance of U Orionis of 260 pc. (author).

International Nuclear Information System (INIS)

Determining the radial distribution of the thermal neutron field in the core of the Dalat reactor was done by the Cu foil activation method. The measured data were fitted by the least square method to determine some physical parameters of the reactor, as follows: 1. Laplacian: B_r"2 = (84.6 +- 5.5)10_-_4/,cm"2. 2. The effective radius: R_e_f_f = (27.6 +- 1.0)cm. 3. The extrapolation distance: #lambda#_r = (8.7 +- 1.0)cm. 4. The unequal coefficient of the effective multiplication: k_r = 1.77 +- 0.11. (author). 3 refs., 4 figs., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

The intermediate silicon layers detector (ISL) was proposed as a part of the upgraded CDF detector at the RUN-II of the Tevatron mean value of pp collider at Fermilab, scheduled to start in year 2000. The ISL is a large-radius (20-30 cm) silicon tracker with a total active area of about 3.5 m. Located in the region between the silicon vertex detector and the central outer tracker, the ISL will allow tracking in the forward region and significantly improve it in the central area. Together with the SVX II the ISL forms a standalone, 3D silicon tracker. The challenge is to build a low-cost device which provides precise 3 D tracking in a approximately equal to 2 m long area with a minimal amount of material for the supporting structure. The conceptual design and the status of the project are reviewed.

CERN Document Server

We present high-resolution hydrodynamical simulations of the degree and direction of polarisation imprinted on the CMB by the Sunyaev-Zel'dovich effect in the the line of sight to massive galaxy clusters. We focus on two contributions which contribute most of the induced CMB polarisation in addition to the intrinsic CMB quadrupole: the radiation quadrupole seen by electrons due to their own velocity in the plane normal to the line of sight, and the radiation quadrupole due to the thermal Sunyaev-Zel'dovich effect, which is generated by a previous scattering elsewhere in the cores of the local and nearby clusters. We show that inside the virial radius of a massive cluster, this latter effect, although being second order in the optical depth, can reach the level of the former effect. These two effects can, respectively, constrain the projected tangential velocity and inner density profile of the gas, if they can be separated with multi-frequency observations. As the ...

Energy Technology Data Exchange (ETDEWEB)

A numerical package called RESID has been assembled to calculate the residual stresses in VAWT blades induced during cold forming. Using a strength of materials - elementary beam theory approach, RESID models the material response with a bilinear stress-strain curve, and the cross-sectional geometry with an array of area increments. Through an iterative solution procedure residual stresses are predicted for a specified final radius of curvature or applied bending moment. RESID results are compared to theoretical solutions for simple geometries and with MARC Finite element results for VAWT blade geometries. Calculating residual stress levels, determining acceptable residual stress levels, and a method of reducing residual stresses are discussed. A complete listing and sample run are included in the appendicies.

International Nuclear Information System (INIS)

Elastic scattering cross sections of keV protons in solids (Z=3-82) are calculated using the partial wave expansion technique and the ''muffin-tin'' bound-atom potential. The differential cross sections for small scattering angles of less than 10deg are smaller than those with the Ziegler-Biersack-Littmark potential at all energies and for all solids, although, for larger angles, the two cross sections agree with each other. The mean free paths of the protons in the solids, obtained from the total cross sections, decrease very slowly with decreasing energy. Furthermore, at low energies they approach half the nearest-neighbor distance, which is taken as the radius of the augmented plane wave sphere in the muffin-tin model of crystalline solids. (orig.).

Energy Technology Data Exchange (ETDEWEB)

A method has been developed to optimize the energy resolution of a horizontally focusing monochromator. The method consists of determining the optimum radius of curvature of the cylindrically bent monochromator crystal by minimizing the total diffracted X-ray flux measured through an X-ray absorption foil. When measured at an absorption edge a global minimum can be identified, which corresponds to the minimum energy band accepted along the entire length of the crystal. Experimental verification of this method has been validated by comparing X-ray fluorescent scans taken for a series of crystal curvatures and by directly measuring the X-ray beam profiles at the corresponding points. The actual optical configuration and asymmetric-cut parameter of the focusing monochromator on beamline X4C at the National Synchrotron Light Source are modeled and ray tracing simulations of the optical system are compared with direct beam profile measurements.

Energy Technology Data Exchange (ETDEWEB)

In a new series of modulated electron cyclotron heating (MECH) on RTP the MECH power was deposited either on-axis or off-axis in plasmas with different values of the plasma current (I{sub p}). Besides confirming all previous MECH results on RTP, the new data can be simulated by assuming a radial profile of the incremental diffusivity ({chi}{sup inc}) that is constant ({chi}{sup inc} < 1 m{sup 2}/s) inside the sawtooth region, makes a sharp step near the inversion radius, and has an offset parabolic profile elsewhere with a value of {chi}{sup inc} {approx} 6 m{sup 2}/s at r/a {approx} 0.6. No significant dependence of {chi}{sup inc} on q{sub a} is observed apart from the position of the transition from low to high {chi}{sup inc}. (author) 5 refs., 4 figs.

International Nuclear Information System (INIS)

We describe in detail the space of the two Kaehler parameters of the Calabi-Yau manifold P_4"("1","1","1","6","9")[D. R. Morrison, 1993] by exploiting mirror symmetry. The large complex structure limit of the mirror, which corresponds to the classical large radius limit, is found by studying the monodromy of the periods about the discriminant locus, the boundary of the moduli space corresponding to singular Calabi-Yau manifolds. A symplectic basis of periods is found and the action of the Sp(6, Z) generators of the modular group is determined. From the mirror map we compute the instanton expansion of the Yukawa couplings and the generalized N=2 index, arriving at the numbers of instantons of genus zero and genus one of each bidegree. We find that these numbers can be negative, even in genus zero. We also investigate an SL(2, Z) symmetry that acts on a boundary of the moduli space. ((orig.)).

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in certain shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing 3-dimensional and multi-component seismic area is being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil-in-place will result in additional oil production by primary and enhanced recovery processes.

Science.gov (United States)

The purpose of this project is to demonstrate targeted infill and extension drilling opportunities, better determinations of oil-in-place, methods for improved completion efficiency and the suitability of waterflooding in Red River and Ratcliffe shallow-shelf carbonate reservoirs in the Williston Basin, Montana, North Dakota and South Dakota. Improved reservoir characterization utilizing three-dimensional and multi-component seismic are being investigated for identification of structural and stratigraphic reservoir compartments. These seismic characterization tools are integrated with geological and engineering studies. Improved completion efficiency is being tested with extended-reach jetting lance and other ultra-short-radius lateral technologies. Improved completion efficiency, additional wells at closer spacing and better estimates of oil in place will result in additional oil recovery by primary and enhanced recovery processes.

CERN Document Server

The possible physical linkage between galactic cosmic rays intensity and the Earth's cloud cover is discussed using the analysis of the first indirect aerosol effect (Twomey effect) and its experimental representation as the dependence of average cloud droplet effective radius on aerosol index characterizing the aerosol concentration in the atmospheric air column of unit section. It is shown that the basic kinetic equation of the Earth's climate energy-balance model is described by the bifurcation equation (with respect to the temperature of the Earth's surface) in the form of fold catastrophe with two governing parameters defining the variations of insolation and Earth's magnetic field (or galactic cosmic rays intensity in the atmosphere), respectively. The principle of hierarchical climatic models construction, which consists in the structural invariance of balance equations of these models evolving on the different time scales, is described. It means that if the ...

DEFF Research Database (Denmark)

Given a set of users, their friend relationships, and a distance threshold per friend pair, the proximity detection problem is to find each pair of friends such that the Euclidean distance between them is within the given threshold. This problem plays an essential role in friend-locator applications and massively multiplayer online games. Existing proximity detection solutions either incur substantial location update costs or their performance does not scale well to a large number of users. Motivated by this, we present a centralized proximity detection solution that assigns each mobile client with a mobile region. We then design a self-tuning policy to adjust the radius of the region automatically, in order to minimize communication cost. In addition, we analyze the communication cost of our solutions, and provide valuable insights on their behaviors. Extensive experiments suggest that our proposed solution is efficient and robust with respect to various ...

Science.gov (United States)

Rapid administration of stable iodine is essential for the saturation and subsequent protection of the thyroid gland against the potential harm caused by radioiodines. This paper proposes the Dutch risk analysis that uses an atmospheric dispersion model to calculate the size of the zones around nuclear power plants where radiological thyroid doses for children might be sufficiently high to warrant iodine administration. Dose calculations for possible releases from the nuclear power plants of Borssele (The Netherlands), Doel (Belgium) and Emsland (Germany) are based on two scenarios in combination with a 1-y set of authentic, high-resolution meteorological data. The dimensions of the circular zones were defined for each nuclear power plant. In these zones, with a radius up to 50 km, distribution of stable iodine tablets is advised. PMID:20332130

DEFF Research Database (Denmark)

Oscillating stars in binary systems are among the most interesting stellar laboratories, as these can provide information on the stellar parameters and stellar internal structures. Here we present a red giant with solar-like oscillations in an eclipsing binary observed with the NASA Kepler satellite. We compute stellar parameters of the red giant from spectra and the asteroseismic mass and radius from the oscillations. Although only one eclipse has been observed so far, we can already determine that the secondary is a main-sequence F star in an eccentric orbit with a semi-major axis larger than 0.5 AU and orbital period longer than 75 days.

Energy Technology Data Exchange (ETDEWEB)

A study of the ..pi..1g/sub 9/2/ orbit size in /sup 88/Sr, /sup 90/Zr, and /sup 92/Mo is presented. The rms radius for the point-proton density is extracted by studying transitions to 8/sup +/ states in these nuclei. The radii are consistently larger than a value determined in a magnetic electron scattering experiment on /sup 93/Nb. A qualitative discussion of the ground state occupation of the ..pi..1g/sub 9/2/ orbit based on the transition amplitudes to the 8/sup +/ states is given.

British Library Electronic Table of Contents (United Kingdom)

We consider the evolution of binary systems formed by a Supermassive Black Hole (SMBH) residing in the center of a galaxy or a globular cluster and a star in its immediate vicinity. The star is assumed to fill its Roche lobe, and the SMBH accretes primarily the matter of this star. The evolution of such a system is mainly determined by the same processes as for an ordinary binary. The main differences are that the donor star is irradiated by hard radiation emitted during accretion onto the SMBH; in a detached system, nearly all the donor wind is captured by the black hole, which strongly affects the evolution of the semi-major axis; it is not possible for companions of the most massive SMBHs to fill their Roche lobes, since the corresponding orbital separations are smaller than the radius ...

Energy Technology Data Exchange (ETDEWEB)

This study investigated the influence of different charge typologies and additives on the PCDD/Fs amount produced and on the congener profiles in an iron ore sintering plant. Many tests were carried out combining different typologies of charge (iron materials) and solid fuel ('coke breeze' or 'anthracite') with or without the use of urea. The PCDD/Fs produced ranged from 1.2 to 22.7 {mu} g I-TEQ/ton of agglomerate, whereas the PCDD/Fs released to the ambient air ranged from 0.10 to 1.92 ng I-TEQ/Nm{sup 3} because of cleaning in an electrostatic precipitator (ESP) and a Wetfine scrubber (WS). A more homogeneous charge with a higher amount of fine particles charge appeared to produce a lower PCDD/Fs concentration due to a better combustion but this hypothesis needs further investigations on charges having different dimension particles. Only a ...

International Nuclear Information System (INIS)

Ion desorption from a condensed gas solid Ne impacted by singly- and multiply-charged Ar"q"+ ions (q = 1-7) has been investigated. Various secondary ions such as cluster ions, Ne"+_n (n = 2-20) as well as atomic ions are observed. Mass spectral patterns, thickness dependence of the yields, and kinetic energy distributions of the desorbed Ne"+_n (n = 1,2) depend strongly on the projectile charge state. These results indicate that the dissipation of the projectile potential energy on the surface leads to the desorption of the monomer and small cluster ions by a Coulomb repulsion between adjacent target ions.

CERN Document Server

We use the semi-classical approximation in perturbative scalar quantum electrodynamics to calculate the quantum correction to the Larmor radiation formula to first order in Planck's constant in the non-relativistic approximation, choosing the initial state of the charged particle to be a momentum eigenstate. We calculate this correction in two cases: in the first case the charged particle is accelerated by a time-dependent but space-independent vector potential whereas in the second case it is accelerated by a time-independent vector potential which is a function of one spatial coordinate. We find that the corrections in these two cases are different even for a charged particle with the same classical motion. The correction in each case turns out to be non-local in time in contrast to the classical approximation.

International Nuclear Information System (INIS)

Electrodynamic properties of processes involving charged tachyons are considered in connection with the real superluminal Lorentz transformations. These transformations are interpreted without making use of a tachon corridor and so that the interaction of tachyons from subluminal sources with ordinary matter is Lorentz invariant. Transformations of the electromagnetic fields are deduced from the extended principle of relativity. They are necessary in order to obtain the field equations that are satisfied by fields obeying Maxwell equations relative to superluminal inertial frames with respect to subluminal inertial frames. The field equations allow one to get the dependence of the field energy density and its current on the field strengths. The resulting equations are applied in a discussion of plane electromegnetic waves, sent out by a superluminal source. The obtained electrodynamics allows the existence of charged tatric ...

Energy Technology Data Exchange (ETDEWEB)

Charge transport in disordered organic semiconductors is generally described as thermally activated hopping in a gaussian distribution of localized states. The presence of charge traps is critical to the performance of organic electronic devices, since trapped charge carriers do no longer contribute to the current flow. The trap distribution in the polymer poly(3-hexylthiophene) (P3HT) is investigated by applying the fractional thermally stimulated current technique. Thereby, a low temperatur double-peak distribution has been revealed. One of the peaks is believed to belong to the tail of the intrinsic density of states, whereas the other trap is strongly affected by exposure to oxygen. We discuss the influence of oxygen exposure time on the trap distribution.

CERN Document Server

Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. The excess of diffuse Galactic Gamma Rays from EGRET shows all the features expected from DMA. The new precise measurements of the antiproton and positron fractions from PAMELA are compared with the EGRET excess. It is shown that the charged particles are strongly dependent on the propagation model used. The usual propagation models with isotropic propagation models are incompatible with the recently observed convection in our Galaxy. Convection leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space. It is shown that such anisotropic propagation models including convection prefer a contribution from DMA for the ...

International Nuclear Information System (INIS)

A theoretical study of electron and positron band structures of zinc-blende AlN and InN and their alloy Al_0_._5In_0_._5N is presented using the first-principles full-potential linearized augmented plane-wave method. Equilibrium lattices constants are determined from the total-energy minimization method. The results are compared with previous calculations and with experimental measurement. Electron and positron charge densities are computed as function of position in the unit cell. Detailed plots of distributions are along the direction. The ionicity factors are calculated by means of three different approaches. The calculated results of the positron charge density reflect the high insight for the annihilation effect.

International Nuclear Information System (INIS)

Purpose: To obtain stabilized operation by preventing over heat in emergency cooling pumps upon accidents of flow regulators. Constitution: A pressure suppression chamber pool and a pressure vessel are communicated to each other with a pipeway and the water in the suppression pool is charged by a charging pump to the pipeway. The pipeway is interposed with an emergency cooling pump so as to feed water in the pipeway to the pressure vessel and a water source and the emergency cooling pumps are connected by way of a closed pipeway. Further, the closed pipeway and the pipeway interposed with the charging pump are communicated to each other by way of a connecting pipeway, to which are interposed an instrument for detecting the increase in the temperature of the emergency cooling pumps due to abnormality in the closed pipe (such as troubles in flow regulators) and outputting control signals and an electrically actuated valve ...

Energy Technology Data Exchange (ETDEWEB)

We demonstrate control and improvement of charge injection in organic electronic devices by utilizing self-assembled monolayers (SAMs) to manipulate the Schottky energy barrier between a metal electrode and the organic electronic material. Hole injection from Cu electrodes into the electroluminescent conjugated polymer poly[2-methoxy,5-(2{sup {prime}}-ethyl-hexyloxy)-1,4-phenylene vinylene] was varied by using two conjugated-thiol based SAMs. The chemically modified electrodes were incorporated in organic diode structures and changes in the metal/polymer Schottky energy barriers and current{endash}voltage characteristics were measured. Decreasing (increasing) the Schottky energy barrier improves (degrades) charge injection into the polymer. {copyright} {ital 1997 American Institute of Physics.}

Energy Technology Data Exchange (ETDEWEB)

This paper describes the development and testing of a system to provide isolated power to the cathode-subsystem electronics of an x-ray tube. These components are located at the cathode potential of several hundred kilovolts, requiring a supply of power isolated from this high voltage. In this design a fiber-optically connected photonic power system (PPS) is used to recharge a lithium-ion battery pack, which will subsequently supply power to the cathode-subsystem electronics. The suitability of the commercially available JDSU PPS for this application is evaluated. The output of the ppe converter is characterized. The technical aspects of its use for charging a variety of Li-Ion batteries are discussed. Battery charge protection requirements and safety concerns are also addressed.

Energy Technology Data Exchange (ETDEWEB)

Autonomous robots or remotely operated vehicles have raised high hopes in the military and industrial communities because of the potential safety improvement and gain of productivity they may provide. Waste management on nuclear sites, pallet manipulation in factories, interventions on battle-fields, etc., are actively studied. A lot of these applications require powerful four-wheel vehicles, the kinematics of which is similar to that of a car. Such vehicles have three degrees of freedom: the (x,y) positions in a plane and the orientation of the vehicle. Path planning is often understood as only changing the position of the vehicle, whereas the tasks performed by this kind of robot requires a perfect orientation of the vehicle: forklifting a pallet or docking at a loading or unloading station requires accuracy in the orientation of the vehicle. It is this requirement and the kinematic constraints of the motion mode which have led to the path-planning algorithm presented in this paper. ...

Energy Technology Data Exchange (ETDEWEB)

Small unilamellar vesicles which form when gel-state long-chain phosphatidylcholines are mixed with micellar short-chain lecithins undergo an increase in size as the long-chain species melts to its liquid-crystalline form. Analysis of the vesicle population with quasi-elastic light scattering shows that the particle size increases from 90-A radius to greater than 5000-A radius. Resonance energy transfer experiments show total mixing of lipid probes with unlabeled vesicles only when the Tm of the long-chain phosphatidylcholine is exceeded. This implies that the large size change represents a fusion process. Aqueous compartments are also mixed during this transition. 31P NMR analysis of the vesicle mixtures above the phase transition shows a great degree of heterogeneity with large unilamellar particles coexisting with oligo- and multilamellar structures. Upon cooling the vesicles below the Tm, the original size distribution (e.g., small ...

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 ...

UK PubMed Central (United Kingdom)

This paper summarizes the deliberations of a work group charged with addressing specific questions relevant to risk estimation in developmental neurotoxicology. We focused on eight questions. a) Does...Full Text Available

CERN Document Server

We show that, in addition to radiation travelling at the speed of light, QED theory predicts a second type of radiation with an infinite velocity. We also show that charge, as it appears in the Dirac equation, may have a triune nature.

International Nuclear Information System (INIS)

Arguments in favour of the possibility of the existence and the non-existence of tachyons are put forward. Some of the theoretical and experimental attempts which have either supported the view that tachyons exist or not are mentioned. In the light of evidence, available as of now, it is surmised that they may not exist and if they do, they may be neutral in charge. (K.B.).

Energy Technology Data Exchange (ETDEWEB)

Perturbative approach to two-dimensional gravity and supergravity is considered. One-loop renormalization of the central charge of SL(2,R) Kac-Moody algebra is calculated perturbatively by functional integration and by explicit calculations of the Feynman diagrams. Also the wavefunction renormalization and the anomalous dimensions in the presence of gravity are calculated.

Energy Technology Data Exchange (ETDEWEB)

The future e{sup +}e{sup -} linear colliders can also operate in the e{gamma} or {gamma}{gamma} modes. In the context of the top-color assisted technicolor (TC2) model, we study the single charged top-pion production process {gamma}{gamma} {yields} tb-bar{pi}{sub t}{sup -}. The results show that the production rates can reach the level of tens fb with reasonable parameter values. So one can expect that enough signals could be produced in future high-energy linear collider experiments. Furthermore, the flavor-changing (FC) decay mode {pi}{sub t}{sup -} {yields} bc-bar is the best channel to detect the charged top pion due to the clean standard model background. With a large number of events and the clean background, the charged top pion should be observable at future linear colliders operating in {gamma}{gamma} mode at the TeV energy scale.

Energy Technology Data Exchange (ETDEWEB)

During the past 3 years, progress was made in elucidating the excited state structures of Pt(diimine)(dithiolate) complexes, while more recent efforts focused on the photochemistry of these complexes and electronic structure of other dithiolate systems. A carbonyl-Ir-maleonitrile dithiolate complex is also studied.

UK PubMed Central (United Kingdom)

In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

It is still a vision at the time being, but wind power and electric cars may complement each other efficiently: Batteries are charged when the power demand of the grid has been saturated. In case of sudden demand peaks, the stored power is transmitted back into the grid. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to present a summary of new methods, employing Lie algebraic tools, for characterizing beam dynamics in charged-particle optical systems. These methods are applicable to accelerator design, charged-particle beam transport, electron microscopes, and also light optics. The new methods represent the action of each separate element of a compound optical system, including all departures from paraxial optics, by a certain operator. The operators for the various elements can then be concatenated, following well-defined rules, to obtain a resultant operator that characterizes the entire system. This paper deals mostly with accelerator design and charged-particle beam transport. The application of Lie algebraic methods to light optics and electron microscopes is described elsewhere (1, see also 44). To keep its scope within reasonable bounds, they restrict their treatment of accelerator design and ...

Energy Technology Data Exchange (ETDEWEB)

Thin Fe and Ta layers of 30-45 nm thickness, deposited via magnetron sputtering on Si (1 0 0) substrates, were bombarded at room temperature with 100 keV Ar{sup 1+} or Ar{sup 8+} or with 250 keV Xe{sup 1+} or Xe{sup 19+} ions in order to test the influence of the ion charge state on the surface sputtering and interface mixing. The samples were characterized by means of Rutherford backscattering at 0.9-3.0 MeV {alpha}-particle energy, time-of-flight elastic recoil detection analysis with a 53 MeV {sup 127}I{sup 10+} beam and atomic force microscopy. No influence of the charge state on the sputtering and athermal mixing rate was observed in the case of the Ta/Si system. However, in the case of the Fe/Si system, the ion charge was observed to have an influence on the mixing rate.

International Nuclear Information System (INIS)

The systems for which the algebra of gauge transformations in the lagrangian formalism is closed, are considered. The hamiltonian BRST charge and the BRST-invariant hamiltonian are found explicitly. Their expansions in powers of the ghost variables contain, in general, an infinite number of terms. (orig.).

UK PubMed Central (United Kingdom)

BackgroundAlthough ivermectin is distributed free of charge through the African Programme for Onchocerciasis Control (APOC), not all eligible individuals within communities receive...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Electrification of Teflon (PTFE) particles pneumatically transported while repeating collision with the wall is different from the cases of nylon 66 or PMMA. PTFE is known as negatively charging substance. Extremely little electrification was found when vertically colliding to the wall. By experiments, it was found that: 1. In the case of vertical collision, electrification was extremely low. 2. Chareg amount by collision increases as v cos increases when it is less than 7.5 m/s in a condition that a horizontal component of a collision speed is present. When v cos is more than 7.5 m/s, the charge approaches that of vertical collision. 3. Measured value of collision area roughly coincided with the result of calculation using an equation based on the assumption that the deforamtion depended only on the vertical component of the collision speed. 4. Charge density gets larger for less v cos and more v sin . ...

Energy Technology Data Exchange (ETDEWEB)

Manned-space missions bring an exposure due to corpuscular radiations of which nature is quite different from what we encounter in the ground environment. In the space environment, many secondaries are produced through interactions of cosmic ray primaries with the spacecraft wall and other surrounding materials. Among this large variety of radiation components in the space, the contribution of neutrons to the radiation exposure of astronauts has remained to be studied. Up to today, efforts to measure neutron dose equivalent have been made using passive detector systems. Considering uncertainties involved in current measurements and estimations of high energy neutrons, and their increasing importance for future manned missions, it is necessary to measure neutron spectrum in the spacecraft under realistic conditions. The neutron spectra have never been measured on board a spacecraft, because the neutron measurement requires to discriminate between the neutron events due to ...

Energy Technology Data Exchange (ETDEWEB)

The scattering of a charged scalar field on Coulomb potential on de Sitter space-time is studied using the solution of the free Klein-Gordon equation. We find that the scattering amplitude is independent of the choice of the picture and in addition the total energy is conserved in the scattering process.

Energy Technology Data Exchange (ETDEWEB)

The pulse radiolysis technique has been employed in studying charge-transfer reactions of anionic C{sub 2}O{sub 4}{sup {minus}}, and cationic C{sub 2}O{sub 4}{sup +} species in supercritical carbon dioxide (scCO{sub 2}) over a range of reduced densities {rho}{sub r} = 0.36--1.5 and at a reduced temperature of T{sub r} = 1.03. The absorption spectrum measured in the visible region with a maximum around 700 nm is assigned to the dimer cation C{sub 2}O{sub 4}{sup +}. The pressure dependence of charge-transfer reactions was examined using dimethylaniline (DMA), benzoquinone (BQ), and oxygen as charge acceptors. The reaction rates of DMA with cations, and BQ with anions are at or near the diffusion-controlled limit. The rates decrease an order of magnitude with increase of pressure. The reaction of C{sub 2}O{sub 4}{sup +} with oxygen is much slower with an almost constant rate over the pressure range examined. The measured rate ...

UK PubMed Central (United Kingdom)

In this study we have profiled the free sterol content of cerebrospinal fluid by a combination of charge tagging and liquid chromatography-tandem mass spectrometry. Surprisingly, the most abundant cholesterol...Full Text Available

UK PubMed Central (United Kingdom)

Amino acid transport was studied in membranes of the peptidolytic, thermophilic, anaerobic bacterium Clostridium fervidus. Uptake of the negatively charged amino acid L-glutamate, the neutral amino...Full Text Available

UK PubMed Central (United Kingdom)

A general procedure for stabilization of O2-labile enzymes exploiting "salting out" of oxygen from the microenvironment in the molecular layers immediately adjacent to charged surfaces of polyionic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A general model for wakefield-generated instabilities in linear accelerators, originally developed for cumulative beam breakup [1], is applied to the resistive wall instability. The general solution for various bunch charge distributions and application to various accelerator configurations are presented.

Energy Technology Data Exchange (ETDEWEB)

A generalized integral representation involving two types of charges is explored to construct correlation functions on the plane for c = 1 - 6/(m(m + 1)) < 1 discrete unitary Virasoro series. The various local operator product algebras emerging contain integer, or half-integer, spin fields along with scalar fields. The examples also include a generalization for arbitrary m of the Z/sub 2/sup -// statistics of the Ising model order-disorder fields.

International Nuclear Information System (INIS)

The aim of this paper is to investigate the total ionizing dose (TID) radiation effects on MOS capacitor with nitride/oxide stack gate. The stack gate MOS capacitors are fabricated with 20 nm oxide, 40 nm nitride or 110 nm nitride respectively. Through the analysis of CV curve of the irradiation capacitors, it is found that the degradation of the CV curve is due to a significant increase of interface traps and somewhat smaller oxide charge. It is also shown that the thicker of the nitride, more interface traps and oxide charge will be occurred. (authors)

Energy Technology Data Exchange (ETDEWEB)

The use of canisters filled with a charge of activated charcoal for field measurements of radon surface-emanation rates is well known. The performance of a canister, which is in current use by uranium mining companies and statutory authorities throughout Australia, was investigated using various charcoal thicknesses. To avoid the lower counting efficiencies associated with the smaller charges when measured at the exposed end, the canisters were counted from the closed end, which has become current practice for this canister.

Energy Technology Data Exchange (ETDEWEB)

The paper presents the integration of the SIMBAD space charge module in the UAL framework. SIMBAD is a Particle-in-Cell (PIC) code. Its 3-D Parallel approach features an optimized load balancing scheme based on a genetic algorithm. The UAL framework enhances the SIMBAD standalone version with the interactive ROOT-based analysis environment and an open catalog of accelerator algorithms. The composite package addresses complex high intensity beam dynamics and has been developed as part of the FAIR SIS 100 project.

Energy Technology Data Exchange (ETDEWEB)

A numerical model has been developed to simulate the charging and discharge behaviour of an electrically rechargeable alkaline zinc-air battery. Further a galvanostatic experiment including three charge/discharge cycles has been performed. The cell voltages, the Zn electrode potentials versus a Zn reference, and the O{sub 2} electrode potentials versus a Zn reference calculated with the model are in fairly good agreement with the corresponding experimental data. The model is expected to be useful for zinc-air battery design and for analysis of experimental data. (author)

Energy Technology Data Exchange (ETDEWEB)

An LPP ignition timing control is described for an internal combustion engine including a combustion chamber, means effective to ignite a combustible charge within the combustion chamber and power output apparatus including a rotating crankshaft driven in response to the expansion of the combustible charge following the ignition thereof and having a predefined TDC rotational reference position, the engine being of the type having a normal combustion mode characterized by combustion pressure peaks compatible with closed loop LPP ignition timing control and an abnormal combustion mode which may not be so compatible.

British Library Electronic Table of Contents (United Kingdom)

The interactions of flavonoid, quercetin with sodium dodecyl sulfate (anionic surfactant) and cetyltrimethyl ammonium bromide (cationic surfactant) micelles were investigated. The average location site of quercetin in different micelles was determined by the cyclic voltammetry method with the aid of molecular optimization. The interaction parameters of quercetin with micelles of different charges such as binding constant K and normal binding energy DG were calculated. Furthermore, the morphologic change of the SDS and CTAB spherical micelles and rod-like micelles upon their interaction with quercetin was also observed.

Science.gov (United States)

Molten zone recrystallized as well as sheet grown polycrystalline silicon has shown a minimum in the temperature dependence of the Hall mobility. In order to explain this experimental finding a new model is proposed, which is based on negatively charged grain boundaries for the p-type silicon material under study. This results in a potential well at the grain boundaries instead of the more generally observed potential barrier. A key feature in the model is that the space charge density at the grain boundary depends on the Fermi level position and therefore on temperature. In addition, the change in the measured Hall mobility before and after hydrogen passivation of the grain boundaries is discussed.

Energy Technology Data Exchange (ETDEWEB)

A laser-induced plasma of alkali atoms was studied with a view to efficient recovery of isotope ions, with small charge exchange losses. The electron temperature was measured by the double-probe method for several kinds of excitation schemes, which gave the relationship between temperature and the energy given to ions by laser photons. A charge exchange process between lithium isotopes was also studied in an electromagnetic field. It was shown that optimum electrostatic and magnetic field strength exist which maximise the 'separative power'.

Energy Technology Data Exchange (ETDEWEB)

The emission of light charged particles from heavy fragments of uranium fission induced by 153-MeV protons is studied. The probability of their emission is 2.7 x 10{sup - 2} per fission event. It is found that these particles affect the distribution of angles of fragment divergence and the angular distribution of heavy fragments with respect to the primary-proton beam. Experimental results suggest that the preequilibrium emission of particles is correlated with fission. Two mechanisms of interaction between 153-MeV protons and uranium nuclei are considered. 13 refs., 10 figs., 1 tab.

Energy Technology Data Exchange (ETDEWEB)

Electron scattering data have been used to obtain transition charge densities for the low-lying E2 transitions in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr. These charge densities show a characteristic shape indicative of their microscopic constituency, modified by core-polarization effects. A good description of transitions in the even-even nuclei is obtained by using the measured single-particle transitions in /sup 89/Y as effective densities. .ID LV2086 .PG 19 22

Energy Technology Data Exchange (ETDEWEB)

The centroid and envelope dynamics of a high-intensity charged particle beam are investigated as a beam smoothing technique to achieve uniform illumination over a suitably chosen region of the target for applications to ion-beam-driven high energy density physics and heavy ion fusion. The motion of the beam centroid projected onto the target follows a smooth pattern to achieve the desired illumination, for improved stability properties during the beam-target interaction. The centroid dynamics is controlled by an oscillating "wobbler", a set of electrically-biased plates driven by RF voltage. __________________________________________________

Energy Technology Data Exchange (ETDEWEB)

Nonlinear two-dimensional theory of the space charge of an axially symmetric electron beam propagating in combined right-hand polarized wiggler and uniform axial guide fields in a presence of high-frequency electromagnetic wave is presented. The well-known TE{sub 01} mode in a cylindrical waveguide for the model of radiation fields and paraxial approximation for the wiggler field are used. Space charge field components are written in the Lagrange coordinates by the twice averaged Green`s functions of two equally charged infinitely thin discs. For that {open_quotes}compensating charges{close_quotes} method is applied in which an electron ring model is substituted by one with two different radii and signs discs. On this approach the initial Green`s functions peculiarities are eliminated and all calculations are considerably simplified. Coefficients of a twice averaged Green`s function expansion into a ...

Science.gov (United States)

The simultaneous diffusion of Si and the dopants B, P, and As has been studied by the use of a multilayer structure of isotopically enriched Si. This structure, consisting of 5 pairs of 120 nm thick natural Si and {sup 28}Si enriched layers, enables the observation of {sup 30}Si self-diffusion from the natural layers into the {sup 28}Si enriched layers, as well as dopant diffusion from an implanted source in an amorphous Si cap layer, via Secondary Ion Mass Spectrometry (SIMS). The dopant diffusion created regions of the multilayer structure that were extrinsic at the diffusion temperatures. In these regions, the Fermi level shift due to the extrinsic condition altered the concentration and charge state of the native defects involved in the diffusion process, which affected the dopant and self-diffusion. The simultaneously recorded diffusion profiles enabled the modeling of the coupled dopant and self-diffusion. From the modeling of the simultaneous diffusion, the ...

International Nuclear Information System (INIS)

Results of an experimental study of the interaction of 140 MeV alpha particles with _9_0Zr nuclei resulting in fragmentation of the alpha particle are reported. The experimental observations of the study are analyzed and are found to show that alpha particle breakup reactions leading to at least 4-body final states, composed of two charged alpha particle fragments, contribute significantly to the singles yield of charged fragments observed at a fixed forward angle. The conclusions are based on coincidence measurements where one charged fragment is detected at a small forward angle which remains fixed, while the second charged fragment is detected at a series of coplanar secondary angles. The largest coincidence charged particle yield for the multiparticle final state events results from _9_0Zr(#alpha#,pp)X reactions, where both of the measured protons have energy distributions ...

Energy Technology Data Exchange (ETDEWEB)

Powder mold type solid state battery was fabricated, and positive electrode compounding ratio and the battery characteristics were studied. The current density depended greatly on the TiS2 content of positive electrode material, and the current density showed maximum value of 800 {mu}A/cm{sup 2} at a TiS2 content of 40 wt%. This composition is expected to be the best to provide better charge-discharge characteristics. The rate capability of TiS2 is dominated by Li{sup +} ion in positive electrode. Further, the diffusion of lithium ion is greatly dominated by TiS2 in positive electrode, compounding ratio of solid state electrolyte and its particle size. Results of charge-discharge characteristics studied for various charge-discharge current densities revealed that the rate capability of TiS2 was more than 50% for a current density of less than 254 {mu}A/cm{sup 2}, and this battery system proved the possibility of high rate ...

Energy Technology Data Exchange (ETDEWEB)

An x-ray zone plate was fabricated using the novel approach of focused ion beam (FIB) milling. The FIB technique was developed in recent years, it has been successfully used for transmission electron microscopy (TEM) sample preparation, lithographic mask repair, and failure analysis of semiconductor devices. During FIB milling, material is removed by the physical sputtering action of ion bombardment. The sputter yield is high enough to remove a substantial amount of material, therefore FIB can perform a direct patterning with submicron accuracy. The authors succeeded in fabricating an x-ray phase zone plate using the Micrion 9500HT FIB station, which has a 50 kV Ga{sup +} column. Circular Fresnel zones were milled in a 1.0-{micro}m-thick TaSiN film deposited on a silicon wafer. The outermost zone width of the zone plate is 170 nm at a radius of 60 {micro}m. An achieved aspect ratio was 6:1.

International Nuclear Information System (INIS)

Tremendous progress in the science of extrasolar planets has been achieved since the discovery of a Jupiter orbiting the nearby Sun-like star 51 Pegasi in 1995. Theoretical models have now reached enough maturity to predict the characteristic properties of these new worlds, mass, radius, atmospheric signatures, and can be confronted with available observations. We review our current knowledge of the physical properties of exoplanets, internal structure and composition, atmospheric signatures, including expected biosignatures for exo-Earth planets, evolution, and the impact of tidal interaction and stellar irradiation on these properties for the short-period planets. We discuss the most recent theoretical achievements in the field and the still pending questions. We critically analyze the different solutions suggested to explain abnormally large radii of a significant fraction of transiting exoplanets. Special attention is devoted to the recently discovered ...

CERN Document Server

Homogeneity for highly asymmetric fields has been studied for a Siemens PRIMUS linear accelerator. The flattening filter has a radius smaller than the primary collimator one, creating inhomogeneities that affect large fields in areas far from the collimator axis, and asymmetric fields with large offset. Profiles and absolute dose have been measured in fields with two jaws at maximal position (20 cm) and the other two at maximal overtravel (10 cm.), corresponding to 10 x 10 fields with extreme offset. Profiles have a remarkable gradient decreasing towards the beam edge, making these fields unsuitable for treatments. Results show that the design of the primary collimator and flattening filter assembly has direct consequences in homogeneity. This can have clinical consequences for treatments involving fields that include these inhomogeneous areas. Comparisons with the treatment planning system (Philips Pinnacle) calculations, that computes under the hypotheses of a ...

CERN Document Server

We analyse how the structure of the inner curst is influenced by the pairing correlations. The inner-crust matter, formed by nuclear clusters immersed in a superfluid neutron gas and ultra-relativistic electrons, is treated in the Wigner-Seitz approximation. The properties of the Wigner-Seitz cells, i.e., their neutron to proton ratio and their radius at a given baryonic density, are obtained from the energy minimization at beta equilibrium. To obtain the binding energy of baryonic matter we perform Skyrme-HFB calculations with zero-range density-dependent pairing forces of various intensities. We find that the Wigner-Seitz cells have much smaller numbers of protons compared to previous calculations. For the dense cells the binding energy of the configurations with small proton numbers do not converge to a well-defined minimum value which precludes the determination of their structure. We show that for these cells there is a significant underestimation of the ...