Estimation of applicability of perturbation theory to solution of the kinetic Boltzmann equation in calculations of charge-carrier relaxation time in isotropic polycrystalline <Emphasis Type="Italic">p-</Emphasis>silicon

A condition is formulated for application of perturbation theory to solution of the kinetic Boltzmann equation in calculations of charge-carrier relaxation time in an isotropic silicon polycrystal, where holes are scattered both by a disordered system of potential barriers formed on crystallite surfaces and by a disordered lattice of silicon atoms characterized by local ordering. The total specific resistance of p-type isotropic polycrystalline silicon is estimated for the grain size d = 230 ?, temperature T = 300 K, and hole concentration p = (5.0 – 10.0) ⋅ 10¹⁹ cm⁻³. The calculated specific resistances of p-type polycrystalline silicon are compared with the experimental data.     

Recent high-<Emphasis Type="Italic">p</Emphasis><Subscript><Emphasis Type="Italic">T</Emphasis></Subscript> results from STAR

We present selected recent results of multi-hadron correlation measurements in azimuth and pseudorapidity at intermediate and high p _T in Au+Au collisions at , from the STAR experiment at RHIC. At intermediate p _T , measurements are presented that attempt to determine the origin of the associated near-side (small Δφ) yield at large pseudo-rapidity difference Δη that is found to be present in heavy ion collisions. In addition, results are reported on new multi-hadron correlation measures at high-p _T that use di-hadron triggers and multi-hadron cluster triggers with the goal to constrain the underlying jet kinematics better than in the existing measurements of inclusive spectra and di-hadron correlations.     

Improvement of <Emphasis Type="Italic">n</Emphasis>-ZnO/<Emphasis Type="Italic">p</Emphasis>-Si photodiodes by embedding of silver nanoparticles

The photo-current of n-ZnO/p-Si heterojunction photodiodes was improved by embedding Ag nanoparticles in the interface (ZnO/nano-P_Ag/p-Si), and the ratio between photo- and dark-current increased by about three orders more than that of a n-ZnO/p-Si specimen. The improvement in the photo-current resulted from the light scattering of embedded Ag nanoparticles. The I–V curve of n-ZnO/p-Si degraded after thermal treatment (A-ZnO/p-Si) because the silicon robbed the oxygen from ZnO to form amorphous silicon dioxide and left an oxygen vacancy. Notably, the properties of ZnO/nano-P_Ag/p-Si were better in the time-dependent photoresponse under 10 V bias. Ag nanoparticles (15–20 nm) scattered the UV light randomly and increased the probability for the absorption of ZnO to enhance the properties of the photodiode.     

Noncommutative electromagnetism as a large <Emphasis Type="Italic">N</Emphasis> gauge theory

We map noncommutative (NC) U(1) gauge theory on ℝ _C ^d ×ℝ _NC ²ⁿ to U(N→∞) Yang–Mills theory on ℝ _C ^d , where ℝ _C ^d is a d-dimensional commutative spacetime while ℝ _NC ²ⁿ is a 2n-dimensional NC space. The resulting U(N) Yang–Mills theory on ℝ _C ^d is equivalent to that obtained by the dimensional reduction of (d+2n)-dimensional U(N) Yang–Mills theory onto ℝ _C ^d . We show that the gauge-Higgs system (A _μ ,Φ ^a ) in the U(N→∞) Yang–Mills theory on ℝ _C ^d leads to an emergent geometry in the (d+2n)-dimensional spacetime whose metric was determined by Ward a long time ago. In particular, the 10-dimensional gravity for d=4 and n=3 corresponds to the emergent geometry arising from the 4-dimensional N=4{\mathcal{N}}=4 vector multiplet in the AdS/CFT duality. We further elucidate the emergent gravity by showing that the gauge-Higgs system (A _μ ,Φ ^a ) in half-BPS configurations describes self-dual Einstein gravity.     

Re-appraisal of the <Emphasis Type="Italic">P,T</Emphasis>-odd interaction constant <Emphasis Type="Italic">W</Emphasis><Subscript>d</Subscript> in YbF: Relativistic configuration interaction approach

Restricted active space (RAS) configuration interaction (CI) approach is employed to compute the P,T-odd interaction constant W _d for the ground (²Σ_1/2) state of YbF molecule. The present estimate of W _d = −1.164 × 10²⁵ Hz/e-cm is expected to provide a reliable limit on the electron’s electric dipole moment (EDM), d _e.     

Partial-wave analysis for elastic <Emphasis Type="Italic">p</Emphasis><Superscript>13</Superscript>C scattering at astrophysical energies

A standard partial-wave analysis was performed on the basis of known measurements of differential cross sections for elastic p ¹³C scattering at energies in the range 250–750 keV. This analysis revealed that, in the energy range being considered, it is sufficient to take into account the ³ S ₁ wave alone. A potential for the triplet ³ S ₁-wave state of the p ¹³C system in the region of the J ^p T = 1⁻¹ resonance at 0.55 MeV was constructed on the basis of the phase shifts obtained from the aforementioned partial-wave analysis.     

Fitting Cosmological Data to the Function <Emphasis Type="Italic">q</Emphasis>(<Emphasis Type="Italic">z</Emphasis>) from GR Theory: Modified Chaplygin Gas

In the Friedmann cosmology, the deceleration of the expansion q plays a fundamental role. We derive the deceleration as a function of redshift q(z) in two scenarios: ΛCDM model and modified Chaplygin gas (MCG) model. The function for the MCG model is then fitted to the cosmological data in order to obtain the cosmological parameters that minimize χ ². We use the Fisher matrix to construct the covariance matrix of our parameters and reconstruct the q(z) function. We use Supernovae Ia, WMAP5, and BAO measurements to obtain the observational constraints. We determined the present acceleration as q ₀ = − 0.65 ±0.19 for the MCG model using the Union2 dataset of SNeIa, BAO, and CMB and q ₀ = − 0.67 ±0.17 for the Constitution dataset, BAO and CMB. The transition redshift from deceleration to acceleration was found to be around 0.80 for both datasets. We have also determined the dark energy parameter for the MCG model: Ω _X0 = 0.81 ±0.03 for the Union2 dataset and Ω _X0 = 0.83 ±0.03 using the Constitution dataset.     

The effect of fast neutrons on the electrophysical properties of nuclear-doped <Emphasis Type="Italic">p</Emphasis>-silicon

The influence of the defects induced by fast-neutron irradiation on the rate of charge-carrier removal in nuclear-doped silicon (p-Si < B, P>) and a test p-Si < B > sample is studied by measuring the Hall coefficient and resistivity at room temperature. It is shown that the rate of removal of charge carriers in p-Si < B, P > is higher than that in p-Si < B>. A barrier model is developed to explain the observed effect.     

On the <Emphasis Type="Italic">K</Emphasis><Superscript>+</Superscript><Emphasis Type="Italic">d</Emphasis> interaction at low energies

The Kd reactions are considered in the impulse approximationwithNN final-state interactions (FSI) taken into account. Realistic parameters for the KN phase shifts are used. The “quasi-elastic” energy region, in which the elementary KN interaction is predominantly elastic, is considered. The theoretical predictions are compared with the data on the K ⁺ d → K ⁺ pn, K ⁺ d → K⁰ pp, K ⁺ d → K ⁺ d, and K ⁺ d total cross sections. The NN FSI effect in the reaction K ⁺ d → K ⁺ pn has been found to be large. The predictions for the Kd cross sections are also given for slow kaons, produced from ϕ(1020) decays, as the functions of the isoscalar KN scattering length a ₀. These predictions can be used to extract the value of a ₀ from the data. The text was submitted by the authors in English.     

Re-evaluation of the LHC potential for the measurement of <Emphasis Type="Italic">m</Emphasis><Subscript><Emphasis Type="Italic">W</Emphasis></Subscript>

We present a study of the LHC sensitivity to the W boson mass based on simulation studies. We find that both experimental and phenomenological sources of systematic uncertainties can be strongly constrained with Z measurements: the lineshape, dσ _Z /dm, is robustly predicted, and its analysis provides an accurate measurement of the detector resolution and absolute scale, while the differential cross-section analysis, d² σ _Z /dydp _T , absorbs the strong interaction uncertainties. A sensitivity δ m _W ∼7 MeV for each decay channel (W→e ν, W→μ ν), and for an integrated luminosity of 10 fb⁻¹, appears as a reasonable goal.     

Exact Results for Topological Strings on Resolved <Emphasis Type="Italic">Y</Emphasis><Superscript><Emphasis Type="Italic"> p</Emphasis>,<Emphasis Type="Italic">q</Emphasis></Superscript> Singularities

We obtain exact results in α′ for open and closed A-model topological string amplitudes on a large class of toric Calabi-Yau threefolds by using their correspondence with five dimensional gauge theories. The toric Calabi-Yaus that we analyze are obtained as minimal resolution of cones over Y ^p,q manifolds and give rise via M-theory compactification to SU(p) gauge theories on . As an application we present a detailed study of the local case and compute open and closed genus zero Gromov-Witten invariants of the orbifold. We also display the modular structure of the topological wave function and give predictions for higher genus amplitudes. The mirror curve in this case is the spectral curve of the relativistic A ₁ Toda chain. Our results also indicate the existence of a wider class of relativistic integrable systems associated to generic Y ^p,q geometries.     

Inclusive measure of |<Emphasis Type="Italic">V</Emphasis><Subscript><Emphasis Type="Italic">ub</Emphasis></Subscript>| with the analytic coupling model

By analyzing B→X _u ℓ ν _ℓ spectra with a model based on soft-gluon resummation and an analytic time-like QCD coupling, we obtain

Magnetoresistivity and acoustoelectronic effects in a tilted magnetic field in <Emphasis Type="Italic">p</Emphasis>-Si/SiGe/Si structures with an anisotropic <Emphasis Type="Italic">g</Emphasis> factor

Magnetoresistivity ρ _xx and ρ _xy and the acoustoelectronic effects are measured in p-Si/SiGe/Si with an impurity concentration p = 1.99 × 10¹¹ cm⁻² in the temperature range 0.3–2.0 K and an tilted magnetic field up to 18 T. The dependence of the effective g factor on the angle of magnetic field tilt θ to the normal to the plane of a two-dimensional p-Si/SiGe/Si channel is determined. A first-order ferromagnet-paramagnet phase transition is observed in the magnetic fields corresponding to a filling factor ν = 2 at θ ≈ 59°–60°.     

Reconstruction of some cosmological models in <Emphasis Type="Italic">f</Emphasis>(<Emphasis Type="Italic">R</Emphasis>,<Emphasis Type="Italic">T</Emphasis>) cosmology

In this paper, we reconstruct cosmological models in the framework of f(R,T) gravity, where R is the Ricci scalar and T is the trace of the stress-energy tensor. We show that the dust fluid reproduces ΛCDM, phantom–non-phantom era and phantom cosmology. Further, we reconstruct different cosmological models, including the Chaplygin gas, and scalar field with some specific forms of f(R,T). Our numerical simulation for the Hubble parameter shows good agreement with the BAO observational data for low redshifts, z<2.     

Neutral-meson production in <Emphasis Type="Italic">pp</Emphasis> collisions at RHIC and QCD test of <Emphasis Type="Italic">z</Emphasis> scaling

New experimental data on inclusive cross section of neutral-vector-meson (ω ⁰, ϕ, K _S ⁰) production in proton-proton collisions at = 200 GeV obtained at RHIC are analyzed in the framework of z scaling. Properties of z-presentation are used to predict hadron yields over a wide range of transverse momentum p _T and collisions energy . The next-to-leading-order perturbative QCD calculations of inclusive cross sections of π ⁰ mesons produced in pp and collisions over a wide range of and p _T are compared with ISR, S pS, RHIC data and predictions of z scaling. The dependence of the spectra in p _T and z presentations for different parton distribution and fragmentation functions is studied. The sensitivity of the obtained results to the choice of the renormalization (μ _R ), initial-state factorization (μ _F ), and final-state factorization (fragmentation) (μ _H ) scales is verified. It is shown that self-similar features of particle production dictated by the z scaling give strong restriction on the asymptotic behavior of the inclusive spectra in high-p _T region. The text was submitted by the author in English.     

Synthesis of silver and lithium sub-micro- and nanoparticles coated with derivatives of <Emphasis Type="Italic">p</Emphasis>-<Emphasis Type="Italic">tert</Emphasis>-butyl thiacalix[4]arenes

The effect of solvent nature and temperature on the formation of 3D-dimensional SAM (self-assembled monolayers on nanoparticles) based on synthetically available stereoisomers of p-tert-butyl thiacalix[4]arenes tetrasubstituted at the lower rim by pyrrolidide and octylamide groups (cone, partial cone, and 1,3-alternate) with lithium and silver nanoparticles were determined by dynamic light-scattering and transmission electron microscopy. It was found that the variation of the temperature of the system and the nature of the solvent leads to the formation discrete or extended particles (CH₂Cl₂) (98–110 nm), nanostructures (CH₃CN) (120–295 nm) or three-dimensional SAM (DMF) (1–13 nm; 46–622 nm).     

Hyperfine structure of <Emphasis Type="Italic">S</Emphasis>- and <Emphasis Type="Italic">P</Emphasis>-wave states in muonic-helium ion

Corrections of order α ⁵ and α ⁶ to the hyperfine structure of S- and P-wave energy levels of the muonic-helium ion are calculated. Electron-vacuum-polarization effects, corrections for the nuclear structure, and recoil effects are taken into account. The numerical values obtained for respective hyperfine splitting, −1334.73 meV (1S), −166.64 meV (2S), −58 712.90 μeV (2P _1/2), and −24 290.69 μeV (2P _3/2), can be viewed as a reliable estimate for a comparison with experimental data, and the hyperfine-structure interval of Δ₁₂ = 8ΔE ^hfs(2S) − ΔE ^hfs(1S) = 1.59 meV can be used to test QED predictions.     

Effects of <Emphasis Type="Italic">d</Emphasis>-wave pairing in <Emphasis Type="Italic">n</Emphasis>-type high-temperature superconductors with anisotropic impurity scattering

The temperature dependences of the resistivity of single-crystal films of the Nd_{2 − x} Ce _x CuO_{4 + δ} n-type superconductors with x = 0.14 (underdoped region) and x = 0.15 (optimal doping region) and different degrees of disorder δ have been investigated in various magnetic fields (B ‖ c, J ‖ ab) in the temperature range 0.4–300 K. It has been demonstrated that there are differences in the behavior of the dependences of the slope of the upper critical field $ (dB_{c2} /dT)_{T \to T_c } $ (dB_{c2} /dT)_{T \to T_c } on the disorder parameter for the underdoped samples (x = 0.14) and the samples with the optimal doping (x = 0.15). The study of the dependence of the slope of the upper critical field on the degree of disorder has made it possible to discriminate experimentally between the superconductors with the d pairing and anisotropic s pairing. It has been revealed that the relative stability of the n-type superconductor with the optimal doping with respect to disordering is possibly due to the strong anisotropy of impurity scattering with symmetry of the d type.     

Cosmological Models with Variable <Emphasis Type="Italic">G</Emphasis> in <Emphasis Type="Italic">C</Emphasis>-Field Cosmology

Cosmological models with variable G in C-field cosmology for barotropic fluid distribution in FRW space-time are investigated. To get the deterministic model of the universe, we have assumed that G=R ⁿ where R is the scale factor and n the constant. To obtain the results in terms of cosmic time t, we have assumed n=−1. We find that for n=−1, Creation field (C) and spatial volume increase with time, G and ρ (matter density) decreases with time, the model represent accelerating universe. Thus inflationary scenario exists in the model. The model is also free from horizon. The results so obtained match with the astronomical observations.     

Contribution of the <Emphasis Type="Italic">M</Emphasis>1 process to the astrophysical <Emphasis Type="Italic">S</Emphasis>-factor of the <Emphasis Type="Italic">p</Emphasis><Superscript>2</Superscript>H radiative capture

The experimental data on the astrophysical S-factor of the p ²H radiative capture are well described for energies from 1 keV to 10 MeV using the potential cluster model and the Young schemes of orbital cluster state classification with allowance for the E1 and M1 transitions.