Classical elementary particles in general relativity

Elementary particles, regarded as the constituents of quarks and leptons, are described classically in the framework of the general relativity theory. There are neutral particles and particles having charges±1/3e. They are taken to be spherically symmetric and to have mass density, pressure, and (if charged) charge density. They are characterized by an equation of state P=– suggested by earlier work on cosmology. The neutral particle has a very simple structure. In the case of the charged particle there is one outstanding model described by a simple analytic solution of the field equations.     

Elementary particles in bimetric general relativity. II

The possibility of an elementary particle in the framework of classical bimetric general relativity is explored further. A model is considered which is filled with a pressureless primal fluid having a fixed ratio of charge density to mass density. This ratio is assumed to be0, ± ₀ , where ₀ is a universal constant <0.5. If the particle charge is assumed to be ±1/3e, the mass is a fraction of the Planck mass, the fraction being greater than0.0285.     

Measurement of Inherent Material Density of Nanoparticle Agglomerates

We describe a new technique to measure the size dependent inherent material density of chain agglomerate particles. Measurements were carried out for diesel soot and aluminum/alumina agglomerate particles in the nanometer size range. Transmission electron microscopy was used to measure the volumes of agglomerate particles that were preselected by mass using an aerosol particle mass analyzer. We found that the density of diesel exhaust particles increased from 1.27 to 1.78g/cm³ as particle mobility size increased from 50 to 220nm. When particles are preheated to remove volatile components, the density was 1.77±0.07g/cm³, independent of particle size. The densities measured after heating correspond to the inherent material density of diesel soot. Measurements with aluminum nanoparticles were made downstream of a furnace where aluminum (Al) was converted to alumina (Al₂O₃). From measurements of inherent material density we were able to infer the extent of reaction, which varied with furnace temperature.     

Search for heavy charged particles and for particles with anomalous charge in e+e? collisions at LEP

Using the OPAL data accumulated in 1991–1993 amounting to 74 pb^–1 of integrated luminosity, corresponding to 1.64×10⁶ selected multi-hadronic events, a search has been performed for charged particles with unusual mass or unusual charge. The mass was determined from a combination of momentum and ionization energy loss measurements. No isolation criteria were applied to the tracks examined, so that both isolated particles and particles produced in jets were valid candidates. For particles with chargeQ/e=–1, one candidate with a mass of approximately 4.2 GeV/c² was found, which is compatible with the background rate expected according to a Monte Carlo simulation. The implications of this search for the mass limits of a conjectured stable or quasi-stable charged gluino composite are discussed. Limits are also presented for the production of fractionally-charged particles withQ/e=±2/3 and ±4/3 as well as for particles withQ/e=±2.     

Nitric acid method for fabrication of gate oxides in TFT

We have developed low temperature formation methods of SiO₂ layers which are applicable to gate oxide layers in thin film transistors (TFT) by use of nitric acid (HNO₃). Thick (>10 nm) SiO₂ layers with good thickness uniformity (i.e., ±4%) can be formed on 32 cm × 40 cm substrates by the two-step nitric acid oxidation method in which initial and subsequent oxidation is performed using 40 and 68 wt% (azeotropic mixture) HNO₃ aqueous solutions, respectively. The nitric acid oxidation of polycrystalline Si (poly-Si) thin films greatly decreases the height of ridge structure present on the poly-Si surfaces. When poly-Si thin films on 32 cm × 40 cm glass substrates are oxidized at azeotropic point (i.e., 68 wt% HNO₃ aqueous solutions at 121 °C), ultrathin (i.e., 1.1 nm) SiO₂ layers with a good thickness uniformity (±0.05 nm) are formed on the poly-Si surfaces. When SiO₂/Si structure fabricated using plasma-enhanced chemical vapor deposition is immersed in 68 wt% HNO₃, oxide fixed charge density is greatly decreased, and interface states are eliminated. The fixed charge density is further decreased by heat treatments at 200 °C, and consequently, capacitance-voltage characteristics which are as good as those of thermal SiO₂/Si structure are achieved.     

The asymptotic region of the charge density oscillation around impurities in dilute copper-based alloys

The wipe-out number for the first order quadrupole effect in the magnetic resonance of the matrix nuclei was measured in dilute copper-based alloys to study the asymptotic behaviour of the charge density oscillation around different impurities. The measured values are Cu-Zn: 490 ± 25; Cu-Au: 880 ± 40; Cu-Ni: 1250 ± 125; Cu-Pd: 1200 ± 100; Cu-Pt: 1900 ± 100.     

On the Charge Form Factor and Eigenvalue of Fermion Energy in a Three-Dimensional Electrodynamics

A static field and self-energy of a particle are considered for a particle charge distributed throughout a 2 + 1-measurement space. The potential of the static field for r has the same asymptotics as for the delta form factor, provided an account is taken of the contribution from vacuum polarization; at the origin of coordinates, the above potential is regular. The proposed form factor allows a relation for the particle charge distribution to be derived in a closed form. The diagonal tension-tensor components of the particle-generated field are found to vanish and the particle field mass calculated using the classical method appears to be finite in the case where the proposed form factor is used. This mass coincides with that obtained through quantum calculations by the order of magnitude.     

Fluid-dynamical representations of the Dirac equation

A relative kinetic mass operator is defined bym =c ⁻²·(E −eΦ), and it is shown that bt using it in a symmetric form one can correlate the (charge) velocity operatorα in the Dirac theory exactly with the general quantum mechanical momentum —ih∇. Then the net force, defined as the rate of change of the relative momentum with time, is exactly equal to the Lorentz force. The contribution due to the time variation of mass equals the negative of space variation of the scalar potential, the Newtonian force, whereas the time variation of the charge current absorbs the entire vector potential dependence. The analogous Euler equations can be written either in terms of the charge current or in terms of the mass current. For a many particle system one needs the usual net single particle parameters and the consideration of both the direct and exchange contributions of the two particle interaction. These Euler equations yield two different conditions of the stationary state. It is shown that the charge-current condition is necessary but not sufficient, whereas the mass-current condition retains the appropriate scalar potential dependence. These two conditions are compared for the spherically symmetric case. The charge density, charge current and relative mass current are tabulated for atomic spinors. Differences between the quantum and classical forces for the H ₂ ⁺ molecular ion exhibit the inadequacy of ordinary atomic spinor basis in forming molecular spinors.     

Self-consistent theory of finite Fermi systems and Skyrme–Hartree–Fock method

Recent results obtained on the basis of the self-consistent theory of finite Fermi systems by employing the energy density functional proposed by Fayans and his coauthors are surveyed. These results are compared with the predictions of Skyrme–Hartree–Fock theory involving several popular versions of the Skyrme energy density functional. Spherical nuclei are predominantly considered. The charge radii of even and odd nuclei and features of low-lying 2⁺ excitations in semimagic nuclei are discussed briefly. The single-particle energies ofmagic nuclei are examined inmore detail with allowance for corrections to mean-field theory that are induced by particle coupling to low-lying collective surface excitations (phonons). The importance of taking into account, in this problem, nonpole (tadpole) diagrams, which are usually disregarded, is emphasized. The spectroscopic factors of magic and semimagic nuclei are also considered. In this problem, only the surface term stemming from the energy dependence induced in the mass operator by the exchange of surface phonons is usually taken into account. The volume contribution associated with the energy dependence initially present in the mass operator within the self-consistent theory of finite Fermi systems because of the exchange of high-lying particle–hole excitations is also included in the spectroscopic factor. The results of the first studies that employed the Fayans energy density functional for deformed nuclei are also presented.

     

Charged ±2π-twist Disclinations in Ferroelectric Liquid Crystals

The electrostatic charge of (±2)-twist disclinations in ferroelectric chiral smectic C liquid crystals is introduced as an approximation in order to simplify the evaluation of the electrostatic self-energy of disclination. As an example, electrostatic charges of (±2)-twist disclinations in an infinite sample are evaluated. Screening effects of free charges in a material and of the ferroelectric structure surrounding the disclination are taken into account by introducing a phenomenological depolarization factor.     

Investigating the topological structure of quenched lattice QCD with overlap fermions using a multi-probing approximation

The topological charge density and topological susceptibility are determined by a multi-probing approximation using overlap fermions in quenched SU(3) gauge theory. Then we investigate the topological structure of the quenched QCD vacuum, and compare it with results from the all-scale topological density. The results are consistent.Random permuted topological charge density is used to check whether these structures represent underlying ordered properties. The pseudoscalar glueball mass is extracted from the two-point correlation function of the topological charge density. We study 3 ensembles of different lattice spacing a with the same lattice volume 16~3×32. The results are compatible with the results of all-scale topological charge density, and the topological structures revealed by multi-probing are much closer to all-scale topological charge density than those from eigenmode expansion.     

Adsorbate-substrate bonding and the growth of naphthalene thin films on Ag(1 1 1)

The adsorption kinetics, energetics and growth of naphthalene thin films, from submonolayer to about 10 layers, on a Ag(1 1 1) surface at low temperature in a ultrahigh vacuum chamber are examined by using temperature programmed desorption spectroscopy. The first layer adsorption occurs with a desorption energy of 85 ± 5 kJ/mole and results in an interface dipole of 5 ± 1 D, from charge transfer of approximately 0.2 e from naphthalene to Ag. The surface dipole induced inter-adsorbate repulsion causes the lowering of the adsorption energy within the first layer near the saturation coverage so that the second layer deposition begins before the completion of the first layer. The second layer is a metastable phase with desorption energy, 74 ± 3 kJ/mole, smaller than the multilayer desorption energy of 79 ± 5 kJ/mole. Fractional order desorption kinetics were found for both the metastable and the multilayer phases, suggesting desorption from 2-D islanding and 3-D islanding, respectively.     

Dust in Plasma II. Effects of Secondary Electrons: Ionization and Surface Emission

In this second paper, the effect of secondary electrons on the charge and potential of a dust particle immersed in plasma has been studied. The processes of electron‐induced ionization and those of photo‐electron and secondary electron emission from the particle surface as a function of primary electron temperature have been taken into account. Starting from temperatures as low as 6 eV in an Ar plasma, ionization produces an extra ion flux to the dust surface comparable to that of the ion charge exchange effect. For what concerns the surface emission, results show that a transition from negative to positive dust charge/potential takes place, and that the transition regime is characterized by a non‐monotonic behavior of the electric potential around the particle. In the case of photoelectric emission, the dust charge and potential are monotonic decreasing functions of the electron temperature, while in the case of emission induced by primary electrons a minimum charge/potential is reached before they grow towards positive values. In no case multiple dust charge states have been observed due to the presence of the potential well attached to the particle surface. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

A relativistic gravity train

A nonrelativistic particle released from rest at the edge of a ball of uniform charge density or mass density oscillates with simple harmonic motion. We consider the relativistic generalizations of these situations where the particle can attain speeds arbitrarily close to the speed of light; generalizing the electrostatic and gravitational cases requires special and general relativity, respectively. We find exact closed-form relations between the position, proper time, and coordinate time in both cases, and find that they are no longer harmonic, with oscillation periods that depend on the amplitude. In the highly relativistic limit of both cases, the particle spends almost all of its proper time near the turning points, but almost all of the coordinate time moving through the bulk of the ball. Buchdahl’s theorem imposes nontrivial constraints on the general-relativistic case, as a ball of given density can only attain a finite maximum radius before collapsing into a black hole. This article is intended to be pedagogical, and should be accessible to those who have taken an undergraduate course in general relativity.     

Influence of the initial state of adatoms on the ratio of atoms and ions in a sputtered particle flow

The role of the initial state of adatoms in the formation of the charge composition of a sputtered particle flow is investigated. Calculations are carried out for alkali metal atoms adsorbed on a tungsten surface and subjected to mutual dipole-dipole repulsion. It is shown that the escape probability (yield) of positive ions diminishes as the surface density of adatoms increases, an effect that is enhanced when the initial state ofthe adatoms is taken into account. Zh. Tekh. Fiz. 69, 116–120 (May 1999)     

Theory of resonant Raman scattering from low-energy collective excitations of interacting electrons in quantum wires

The Raman spectra of quantum wires in the region of electronic intra-band excitations are investigated using one- and two-band models based on the Luttinger approximation with spin. Structures related to charge and spin density modes are identified, and analyzed with respect to their behavior with photon energy and temperature. It is found that the low-energy peaks in the polarized spectra, close to resonance that are commonly assigned to “single particle excitations”, can be interpreted as the signature of spin density excitations. A broad structure in the resonant depolarized spectrum is predicted above the frequency of the spin density excitations. This is due to simultaneous but independent propagation of spin and charge density modes. The results, when compared with experiment, show, that the electronic collective excitations of quantum wires at low energies are characteristic for a non-Fermi liquid. Received: 25 March 1998 / Accepted: 3 June 1998     

On the determination of vertical profiles of temperature, charge concentration, and potential in the surface layer of an aircraft

A “3/2 law” law has been established for the vertical charge concentration profile (i.e., the particle concentration is proportional to temperature to a power of 3/2). The expression is derived for the electric field potential produced by charged particles at the upper boundary of the viscous sublayer, as well as for the density current produced by charged particles moving in the air flow streamlining an aircraft. It is shown that all these parameters increase with altitude and assume maximum values at the turbulent layer surface.     

Influence of ethanol on the electrocodeposition of Ni/Al2O3 nanocomposite films

The effect of ethanol on the electrocodeposition of nickel alumina nanocomposites was investigated using an acidic nickel sulfamate electrolyte. The surface charge and sedimentation behaviour of the 13 nm alumina particles in the nickel plating bath were characterized as a function of the ethanol concentration and the pH of the electrolyte. High ethanol contents cause a decrease in the surface charge and dispersion stability of the alumina particles in the plating electrolyte. The effects of the deposition conditions, i.e. ethanol content, current density, and particle content of the electrolyte on the codeposition of nickel alumina composites were investigated systematically. Low values of current density and high amounts of ethanol in the plating bath were found to be beneficial for the particle entrapment. The structure as well as the microhardness of the nickel films were investigated as a function of the electrolyte composition and the particle incorporation. A textural modification combined with a distinct grain refinement was found with increasing ethanol content of the electrolyte and due to the alumina incorporation. The microhardness of the layers increased with decreasing ethanol content of the electrolyte and increasing nanoparticle incorporation.     

Classical model of an electron

Using Penney's balanced field equations it is shown that the electron may be considered as a material ball having charge on its surface. The electromagnetic field energy still turns out to be 3/4 of its total mass. The density of the material ball is found to be half of the square density of charge.     

Heat release of carbon particle formation from hydrogen-free precursors behind shock waves

The process of heat release during carbon particle formation and growth after pyrolysis of carbon suboxide C₃O₂ behind shock waves was investigated. For this goal, temperature and optical density of gas-particle mixtures initially consisting of 3% C₃O₂ + 5% CO₂ in Ar were measured as a function of time. The temperature was determined by two-channel emission-absorption spectroscopy at λ = 2.7 ± 0.4 μm, corresponding to the CO₂ (1,0,1) vibrational band. In the range of initial temperatures behind the shock waves from 1600 up to 2200 K a significant heating of the mixture during particle formation and growth was observed that increased towards higher temperatures. The analysis of the obtained data in combination with previous results about the temperature dependence of the particle size shows a decrease of the heat release of condensation from ∼200 kJ/mol per atom for particles containing ∼1000 atoms to ∼50 kJ/mol per atom for particle containing ∼10⁶ atoms.