N = 1 heterotic / M-theory duality and Joyce manifolds

We present an ansatz which enables us to construct heterotic/M-theory dual pairs in four dimensions. It is checked that this ansatz reproduces previous results and that the massless spectra of the proposed new dual pairs agree. The new dual pairs consist of M-theory compactifications on Joyce manifolds of G₂ holonomy and Calabi-Yau compactifications of heterotic strings. These results are further evidence that M-theory is consistent on orbifolds. Finally, we interpret these results in terms of M-theory geometries which are K3 fibrations and heterotic geometries which are conjectured to be T³ fibrations. Even though the new dual pairs are constructed as non-freely acting orbifolds of existing dual pairs, the adiabatic argument is apparently not violated.     

Some necessary conditions for fermion N-representability

The analogues of the Q and B conditions for the N-representability of a p-particle fermion density operator are derived. These conditions impose some new necessary conditions for the N-representability of 2-density operators. It is shown that the new conditions are no more restrictive than the conventional Q and B conditions.     

Elastic photoelectron-scattering effects in quantitative X-ray photoelectron spectroscopy

We present improved formulae for the correction parameters Q_x and β_eff that are used to account for elastic scattering of photoelectrons in quantitative X-ray photoelectron spectroscopy (XPS). The new formulae are based on new Monte Carlo simulations for 584 photoelectrons in 39 elemental solids that could be excited by Mg Kα and Al Kα X-rays in 315 different XPS configurations. The new simulations differed from similar earlier calculations in that differential elastic-scattering cross sections calculated from the Dirac–Hartree–Fock potential were utilized rather than those from the Thomas–Fermi–Dirac potential, a smaller analyzer acceptance angle was chosen, and the number of trajectories in each simulation was an order of magnitude larger. New values of Q_x and β_eff were obtained for each photoelectron line, each X-ray source, and each XPS configuration. These Q_x and β_eff values could be fitted to simple two-parameter expressions, each a function of the single-scattering albedo and the photoelectron emission angle. Values of Q_x from the new predictive formula differed from the previous expression by less than 1%. Larger deviations in the values of β_eff, up to 2.5%, were found from the new fit to the β_eff parameter. The new expressions for Q_x and β_eff provide a convenient means for correction of elastic-scattering effects in XPS.     

High-pressure phases in the GaSb-Mn system

The effect of high pressure (6 GPa) on the formation of new phases in a polycrystalline mixture GaSb: Mn = 1: 1 upon heating was studied. Sphalerite-type solid solutions with a small amount of Mn form at temperatures below 520–600 K. At higher temperatures, new crystalline GaSbMn phases are synthesized: a phase with a simple cubic structure with a lattice parameter a = 2.946 ± 0.001 Å (at 620–670 K) and a phase with a tetragonal CuAl₂-type structure (space group I4/mcm) with lattice parameters a = 6.426 ± 0.004 Å and c = 5.349 ± 0.004 Å (at 690–870 K). These new phases are metastable under normal conditions and have magnetic properties. The structure, conductivity, and thermal stability of the synthesized phases are investigated, and the products of decomposition of these new phases upon annealing are analyzed.     

New Parameterized Coherent-Entangled State Representation and Its Applications

Based on EPR’s idea of quantum entanglement, new parameterized coherent-entangled states |α,p〉 _μ,ν are introduced in two-mode Fock space, which can be implemented by using a beam splitter. Possible superpositions of |α,p〉 _μ,ν result in some new entangled states. The asymmetric ket-bra integration from |α,p〉 _μ,ν leads to a new one- and two-mode combinatorial squeezing operator with stronger squeezing, which clearly shows the intrinsic relationship between squeezing mechanism and quantum entanglement.     

Termanalyse der 4d 9 5s 5d-Konfiguration im Bogenspektrum des Silbers

The arc spectrum of silver has been remeasured in the range of 1100 to 9800 Å. This yielded some 140 new lines. Analysing these lines together with about 50 previously unidentified lines of Shenstone established 20 new levels. The configurations 4d ⁹ 5s 5p and 4d ⁹ 5s 6s are now completely analysed. In the 4d ⁹ 5s 5d-configuration about half of the expected levels were identified. Two new 4d ⁹ 5s 7s levels were found.     

Stainless super p-branes

The elementary and solitonic supersymmetric p-brane solutions to supergravity theories form families related by dimensional reduction, each headed by a maximal (‘stainless’) member that cannot be isotropically dimensionally oxidized into higher dimensions. We find several new families, headed by stainless solutions in various dimensions D ⩽ 9. In some cases, these occur with dimensions (D, p) that coincide with those of descendants of known families, but since the new solutions are stainless, they are necessarily distinct. The new stainless supersymmetric solutions include a 6-brane and a 5-brane in D = 9, a string in D = 5, and particles in all dimensions 5 ⩽ D ⩽ 9.     

Catalytic reactions in heavy-ion collisions

We discuss a new type of reactions of a ?-meson production on hyperons, ??Y ?? ?Y and antikaons -KN ?? ?Y. These reactions are not suppressed according to Okubo-Zweig-Iizuka rule and can be a new efficient source of ? mesons in a nucleus-nucleus collision. We discuss how these reactions can affect the centrality dependence and the rapidity distributions of the ? yield.     

Analysis of the ν2 and 2ν2-ν2 ozone bands from high-resolution infrared atmospheric spectra

High-resolution (0.02 cm^?1) infrared atmospheric spectra were used for a new analysis of the ν₂ and 2ν₂-ν₂ bands of ozone and for generating a new line parameters compilation. Samples of the spectra and the analysed lines are presented.     

The randomly organized structure of urban ground bus-transport networks in China

In this paper, the evolution dynamical properties of four topological urban ground bus-transport networks (BTNs) in China are empirically researched. As the statistical results of some common used measurements show that there are large fluctuations because of small sample sizes to induce some indistinct conclusions, and there are even incorrect BTN structure pictures as positive degree relation of the adjacent vertices in those BTNs though they are actually uncorrelated at all, i.e., exhibiting “pseudo positive connectivity correction”. Thus in order to uncover the randomly organized architecture of BTNs, new measurements of the average sum of the nearest-neighbors’ degree-degree correlation D_nn(k), and the degree average edges among the nearest-neighbors L(k) are proposed. The obtained results of two new measurements do reflect that the considered BTNs are organized randomly. In this point, those empirical results provide one new framework for a more realistic BTN model, which will capture the underlying evolution principles of a BTN in the geographical topology.     

Crossover scaling behaviour of the quasi-one-dimensional n-vector models

Crossovers in the quasi-one-dimensional n-vector models are discussed by making new scaling hypotheses. Predictions regarding critical point shifts and amplitudes are made for one-to two- and three-dimensional crossovers for 1 ? n ? ∞. Many new scaling functions are obtained exactly and studied by series-expanding methods.     

Arguments against one-boson-exchange models of nuclear forces and new mechanism for intermediate-and short-range nucleon-nucleon interaction

Arguments against the traditional Yukawa-type approach to NN intermediate-and shortrange interaction due to scalar-isoscalar and heavy-meson exchanges are presented. Instead of the Yukawa mechanism for intermediate-range attraction, some new approach based on the formation of a symmetric six-quark bag in the state |(0s)⁶[6]_X, L=0〉 dressed owing to strong coupling to π, σ, and ρ fields is suggested. This new mechanism offers a strong intermediate-range attraction, which replaces effective σ exchange (or excitation of two isobars in the intermediate state) in traditional force models. A similar mechanism with the production of a vector ρ meson in the intermediate six-quark state is expected to lead to a strong short-range spin-orbit nonlocal interaction in the NN system, which may resolve the long-standing puzzle of the spin-orbit force in baryons and in two-baryon systems. The effective interaction in the NN channel provided by the new mechanism will be enhanced significantly if the partial restoration of chiral symmetry is assumed to occur inside the six-quark symmetric bag. A simple illustrative model is developed that demonstrates clearly how well the suggested new mechanism can reproduce NN data. Strong interrelations have been shown to exist between the proposed microscopic model and one-component Moscow NN potential developed by the authors previously and also with some hybrid models and the one-term separable Tabakin potential. The new implications of the proposed model for nuclear physics are discussed.     

Antiferromagnetism of quasi two-dimensional manganese stearate

The magnetic properties of manganese stearate, a highly two-dimensional magnetic material, are found to be changed considerably when it is synthesized by a new procedure. Whereas earlier samples behaved like weak-ferromagnets with ordering temperatures about 5 K, the new material is an antiferromagnet with T_n = 10 K. The reason may be a change in the crystal structure.     

Distinctive signatures for new particles in e+ e− annihilation and z-decay

New particles and new interactions reveal themselves most clearly where standard model contributions are negligibly small. A prominent example with this advantage is the one-lepton inclusive longitudinal structure function (W_L) in e⁺ e^? annihilation and Z-decay. We discuss general features of this approach and present structure functions for two types of new particles (heavy charged fermion, e.g. new sequential lepton or top quark; and supersymmetric scalar lepton, i.e. slepton), along with the (small) standard model “background”. The x-dependence of W_L provides a distinct signature of the identity of the new particle. Extensions of this approach are discussed.     

The light pressure force and the friction and diffusion coefficients for atoms in a resonant nonuniformly polarized laser field

The motion of slow atoms with degenerate energy levels in a resonant, nonuniformly polarized laser field is described by the Fokker-Planck equation for the atomic distribution function in phase space in terms of the semiclassical approach. Field gradient expansions are used for the spatially nonuniform coefficients of the equation. For closed atomic transitions J _g =J→J _e =J+1 (J _g and J _e are the total angular momenta of the ground and excited states, respectively), new analytical results are presented for the light pressure force and the friction and diffusion coefficients in momentum space. These results allow the kinetic effects (laser cooling, localization in optical potential wells, etc.) in a field of arbitrary one-, two-, or three-dimensional configuration to be investigated. In several cases, the new contributions to the friction coefficient are interpreted qualitatively.     

Levels in152Gd and152Sm populated by the decay of152Eu

The energy level schemes of¹⁵²Gd and¹⁵²Sm have been established on the basis of singlesγ-spectra, andγ- γ coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC/β⁺ and β^? decays of¹⁵²Eu to¹⁵²Sm and¹⁵²Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and logf t values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model.     

Potential contrast agents for magnetic resonance imaging

The development ofmagneto-pharmaceuticals plays an important role in the extension of nuclear magnetic resonance into diagnostic medicine. That is the reason why fundamental investigations leading to new insights into NMR contrast agents are presently being considered. The synthesis and the proton relaxation rates of some new contrast agents are presented. The high values ofR ₁, andR ₂ relaxivities of the compounds studied by us are promising for various and novel applications.     

New analytical independent-particle model potential for atoms

A new analytical, independent-particle model potential with four shell-independent parameters is proposed, which is suitable for high, medium, and low Z atoms. The four parameters are determined for 101 atoms from Li to Lr by fitting the results of the X _a method found in the literature. The average fitting error 0.675% of the new potential for the 101 atoms is far better than 3.92% of the widely used Green’s potential. The radial Schrödinger equation with the new potential is solved by using Numerov’s numerical method for 7 typical atoms: Ne, Ca, Zn, Zr, Sn, Yb, and Th. The energy eigenvalues, radial wave functions, and atomic ground-state energy are in good agreement with the results of the X _a method. The new potential here shows greater flexibility and better accuracy compared with the Green’s potential.     

Black holes in higher dimensional space-times

Black hole solutions to Einstein's equations are examined in asymptotically flat N + 1 dimensional space-times. First generalizations of Schwarzschild and Reissner-Nordstrøm solutions are examined in a discussion of static black holes in N + 1 dimensions. Then a new family of solutions is found which describe spinning black holes in higher dimensional space-times. In many respects these new solutions are similar to the familiar Kerr and Schwarzschild metrics which are recovered for N = 3. One exceptional case though is that for N ≥ 5, black holes with a fixed mass may have arbitrarily large angular momentum.     

A theory of quasi-channeling for electrons and positions,quasi-channeling radiation in systems of macroscopic extent,and experimental implications for a short wavelength laser

The theory of electron and positron channeling and radiation production in crystals is extended to macroscopic-scale systems. The new theory examines systems that exhibit periodicity along the axis of beam propagation, specifically, periodic electrostatic fields: the dimensions of the field periodicity (l_z) are much greater than typical interatomic lattice spacing (l_L), e.g., l_z≫l_L. The feasibility of a laser based on this predicted new phenomenon is examined. Differences between the properties of the proposed quasi-channeling radiation and radiation produced by wigglers and free electron lasers (FELs) are discussed. System lengths a factor of 10³ shorter than FELs are expected, with favorable scaling for below 500 eV laser photon output energies.