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In this paper, electronic properties of Janus MSX monolayers (M = Mo, W; X = Se or Te), including electron energy loss near edge structures (ELNES), as K and L2,3 edge spectra of sulfur atoms, have been calculated using a full potential scheme and the augmented plane wave plus local orbitals (APW+lo) method in the framework of density functional theory (DFT). Due to the lack of experimental results, the obtained spectra are compared with the corresponding spectra of MoS2 monolayer. The band structure analysis shows that the Janus MoSSe and WSSe monolayers are direct bandgap semiconductors, while the Janus MoSTe and WSTe monolayers are indirect bandgap semiconductors. In comparison to MoS2, the main structures of the K edge ELNES spectra of sulfur atoms in Janus monolayers occur at lower energies, due to the structural change and increased bond length. The relative reduction of intensities in the main structures predicts the possibility of reducing the number of partial densities of states (PDOS), that is, the reduced p PDOS for the K edge in the corresponding energy range. In the K (L2,3) edge ELNES spectra of the sulfur atom in Janus monolayers and MoS2 monolayers, the main structures are due to the electron transfer to the unoccupied px+py and pz states (3s of sulfur and 4d states of the transition metal). [ABSTRACT FROM AUTHOR]

We propose a new method for calculating the redshift in galaxies, according to which the amount of redshift in the spectrum of each galaxy consists of two parts: about 2/3 of the redshift is due to the speed of the galaxy moving away from us, and about 1/3 is due to the fact that photons moving in the expanding Universe acquire an additional (non-Doppler) redshift. The additional reddening of photons in the spectrum of the galaxy is due to photons coming to us from the past, when the gravitational potential of the universe was lower, and consequently, the frequencies of atomic spectra were also lower than at present. A scheme of a laboratory experiment is proposed that will allow direct measurement of a non-Doppler (additional) part of the cosmological redshift and demonstrate the very fact of the expansion of the universe in real time in about 15 min. The experiment also makes it possible to measure the expansion rate of the universe and its current gravitational potential. These results will help to significantly refine modern ideas about the age of the universe, and about the amount of dark energy and dark matter in it. [ABSTRACT FROM AUTHOR]

The observation of electromagnetic radiation emitted or absorbed by matter was instrumental in revealing the quantum properties of atoms and molecules in the early XX century, and constituted a turning-point in the development of the quantum theory. Quantum mechanics changes dramatically the way radiation and matter interact, making the probability of emission and absorption of light strongly frequency dependent, as clearly manifested in atomic spectra. In this essay, we advocate that gravitational radiation can play, for the quantum aspects of black holes, a similar role as electromagnetic radiation did for atoms, and that the advent of gravitational-wave astronomy can bring this fascinating possibility to the realm of observations. [ABSTRACT FROM AUTHOR]

Explicit formulas for orbital carriers of periods 4, 5 and 6 are reported for discrete-time quadratic dynamics. A systematic investigation of orbital inheritance for periods as high as k ≤ 1 2 is also reported. Inheritance means that unknown orbits may be obtained by nonlinear transformations of known orbits. Such nested orbit within orbit stratification shows orbits not to be necessarily independent of each other as generally assumed. Orbital stratification is potentially significant to rearrange trajectories sums in trace formulas underlying modern semiclassical interpretations of atomic physics spectra. The stratification seems to dominate as the orbital period grows. [ABSTRACT FROM AUTHOR]

The Schrödinger spectrum of a hydrogen atom, modeled as a two-body system consisting of a point electron and a point proton, changes when the usual Coulomb interaction between point particles is replaced with an interaction which results from a modification of Maxwell's law of the electromagnetic vacuum. Empirical spectral data thereby impose bounds on the theoretical parameters involved in such modified vacuum laws. In the present paper the vacuum law proposed, in the 1940s, by Bopp, Landé–Thomas, and Podolsky (BLTP) is scrutinized in such a manner. The BLTP theory hypothesizes the existence of an electromagnetic length scale of nature — the Bopp length ϰ − 1  —, to the effect that the electrostatic pair interaction deviates significantly from Coulomb's law only for distances much shorter than ϰ − 1 . Rigorous lower and upper bounds are constructed for the Schrödinger energy levels of the hydrogen atom, E ℓ , n (ϰ) , for all ℓ ∈ { 0 , 1 , 2 , ... } and n > ℓ. The energy levels E 0 , 1 (ϰ) , E 0 , 2 (ϰ) , and E 1 , 2 (ϰ) are also computed numerically and plotted versus ϰ − 1 . It is found that the BLTP theory predicts a nonrelativistic correction to the splitting of the Lyman- α line in addition to its well-known relativistic fine-structure splitting. Under the assumption that this splitting does not go away in a relativistic calculation, it is argued that present-day precision measurements of the Lyman- α line suggest that ϰ − 1 must be smaller than ≈ 1 0 − 1 8 m. Finite proton size effects are found not to modify this conclusion. As a consequence, the electrostatic field energy of an elementary point charge, although finite in BLTP electrodynamics, is much larger than the empirical rest mass (× c 2 ) of an electron. If, as assumed in all "renormalized theories" of the electron, the empirical rest mass of a physical electron is the sum of its bare rest mass and its electrostatic field energy, then in BLTP electrodynamics the electron has to be assigned a negative bare rest mass. [ABSTRACT FROM AUTHOR]

Factors affecting the on-line detecting thickness of lithium battery pole by laser sensor are mainly the accuracy of the sensor, the inherent frequency and dynamic error of the C scanning mechanism. Improved highly redundant optimal atomic parameters for the thickness of lithium battery pole piece under different circumstances are obtained. The best atomic parameters are extracted in the training phase to construct the sub-optimal atomic function. The results show that, compared with wavelet algorithm and conventional sparse decomposition algorithm, the improved sparse decomposition algorithm has better denoising performance under the condition of lacking prior knowledge. [ABSTRACT FROM AUTHOR]

We investigate the tunneling of ultracold atoms in optical traps by using the path-integral method. We obtain the decay rate for tunneling out of a single-well and discuss how the rate is affected by the level splitting caused by the presence of a second adjacent well. Our calculations show that the transition through the potential barrier can be divided into three regions: the quantum tunneling region, the thermally assisted region and the thermal activation region. The tunneling process is found to be a second-order transition. We also show that level splitting due to tunneling can increase the tunneling rate. [ABSTRACT FROM AUTHOR]

In this paper, the statistical properties of energy levels are studied numerically for atom in parallel electric and magnetic fields, which is an ideal system to examine the contributions of external fields and ionic core to quantum chaos. The Stark maps of diamagnetic spectra and nearest neighbor spacing (NNS) distributions are obtained by diagonalization method incorporating core effect. We identify obvious level anti-crossing and large value of for barium, indicating that core effect has predominant contribution to chaotic dynamics in barium. To study the core effect in detail, we sweep the quantum defect artificially and find that larger core effect will undoubtedly induce stronger chaotic dynamics. [ABSTRACT FROM AUTHOR]

We prove two results on the stability spectrum for Lω1,ω. Here $S^m_i(M)$ denotes an appropriate notion (at or mod) of Stone space of m-types over M. (1) Theorem for unstable case: Suppose that for some positive integer m and for every α < δ(T), there is an M ∈ K with $\vert S^m_i(M)\vert > \vert M\vert^{\beth_\alpha(\vert T\vert)}$. Then for every λ ≥ |T|, there is an M with $\vert S^m_i(M)\vert > \vert M\vert = \lambda$. (2) Theorem for strictly stable case: Suppose that for every α < δ (T), there is Mα ∈ K such that λα = |Mα| ≥ ℶα and $\vert S^m_{i}(M_\alpha)\vert > \lambda_\alpha$. Then for any μ with μℵ0 > μ, K is not i-stable in μ. These results provide a new kind of sufficient condition for the unstable case and shed some light on the spectrum of strictly stable theories in this context. The methods avoid the use of compactness in the theory under study. In this paper, we expound the construction of tree indiscernibles for sentences of Lω1,ω. Further we provide some context for a number of variants on the Ehrenfeucht-Mostowski construction. [ABSTRACT FROM AUTHOR]

We construct a Dirac equation in κ-Minkowski spacetime and analyze its implications. This κ-deformed Dirac equation is expanded as a power series involving derivatives with respect to commutative coordinates and the deformation parameter, a. We show that the κ-deformation breaks the charge conjugation invariance but preserves parity and time reversal. We then study how the hydrogen atom spectrum is modified due to the κ-deformation, applying perturbation theory. Using this, we obtain bounds on the deformation parameter a, which are a few orders higher than the Planck length. We also show that the effects of deformation on the spectrum are distinct from that of Moyal deformation and generalized uncertainty principle. [ABSTRACT FROM AUTHOR]

The SIDDHARTA experiment aims a precise measurement of K-series kaonic hydrogen x-rays and the first-ever measurement of the kaonic deuterium x-rays to determine the strong-interaction energy-level shifts and widths of the lowest lying atomic states. These measurements offer a unique possibility to precisely determine the isospin-dependent kaon-nucleon (KN) scattering lengths [1] which are directly connected with the physics of the KN interaction. Kaonic Helium transitions to the 2p level (L-lines) were as well measured. The experiment has been performed at the DAΦNE e+e- collider which produces the Φ-resonance. The resulting low energy negative charged kaons, coming from the Φ decay, are well suited to be stopped efficiently in a high density gas target for producing such kind of atoms. As x-ray detectors, we employed 144 Silicon Drift Detectors developed especially for this experiment, having good energy resolution of 140 eV FWHM at 6keV and time resolution of sub-micro seconds. The data taking was completed in November 2009. In this paper, an overview of this experiment and preliminary results are presented, together with future plans. [ABSTRACT FROM AUTHOR]

This article deals with the connection between a.m. the hydrogenic radial integrals in the theory of atomic spectra and new properties of Appell's function F2(x, y) to the vicinity of the singular point (1, 1) and to the domain |x|+|y| < 1. In Tables 1-7 exact numerical values of these integrals are first given, i.e., actually for all Mendeleev's table. (Author has all values these of integrals for arbitrary nl-states of H-like atoms, k ≥ 0 and Z ≤ 137). [ABSTRACT FROM AUTHOR]

The static properties of protons are useful for understanding the quark structure of the proton. In his work we have introduced the hypercentral constituent quark model and isospin dependent potentials. Here constituent quarks interact with each other via a potential in which we have taken into account the three-body force effect and the standard two-body potential contributions. According to our model the static properties of protons containing u and d quarks are better than the other models and closer to experimental results. The two key ingredients of this improvement are the effective quark–gluon hypercentral potentials, and hyperfine interaction and isospin dependence potential. Recently, Schrödinger equation has been solved by Giannini but we have solved the Dirac equation exact analytically and we have shown that a considerable improvement in the description of the static properties of proton is obtained with an isospin dependent potential and the complete interaction including spin and isospin terms reproduces the position of the quark. [ABSTRACT FROM AUTHOR]

Glasses of x(ZnO)(50 - x)PbO:50V2O5 system were prepared by melt-quench process in the range x = 0 mol% to 15 mol%. Measurements are reported for DC electrical conductivity as well as thermo electrical power for these samples in both glass and crystalline forms in the temperature range of 27°C and 227°C. The ESR studies of these samples at room temperature are reported. These spectra are characterized by well-resolved eight-line powder pattern. It is observed that the ESR spectra obtained in the crystalline form, the hyperfine structure is nearly smeared out and the spectra are characterized by a relatively broad line with an isotropic g value. The experimental results are analyzed with reference to Mott's model. The analysis shows that at high temperatures the temperature dependence of DC conductivity is consistent with Mott's model for both glass and crystalline samples. The high-temperature thermoelectric power was satisfactorily explained by Heikes' relation and the data also showed evidence of small polaron formation for glass form samples and large polaron formation in crystalline samples. These results indicate that all the glass samples lead metavanadate are n-type at room temperature and the crystalline samples are p-type at room temperature. [ABSTRACT FROM AUTHOR]

We provide a microscopic derivation for the non-Markovian master equation for an atom-cavity system with cavity losses and show that they can induce population trapping in the atomic excited state, when the environment outside the cavity has a non-flat spectrum. Our results apply to hybrid solid state systems and can turn out to be helpful to find the most appropriate description of leakage in the recent developments of cavity quantum electrodynamics. [ABSTRACT FROM AUTHOR]

Dispersive switching effect is examined for a mesoscopic system of coherently injected two-level Rydberg atoms into a driven single-mode superconducting cavity. The effect concerns the switching of the output field by simultaneously varying the atomic and cavity detuning parameters at fixed values of the coherent driving field. For certain atomic coherence parameters, symmetric and asymmetric switching diagrams are exhibited, which include one- and two-way process via multistep transitions between output field states. [ABSTRACT FROM AUTHOR]

In this paper an expert system is presented that was developed with the aim to analyze electron spectra on the threshold energies in collision with triatomic and polyatomic molecules. This expert system was made by updating the expert system for the analysis of the threshold spectra of two-atomic molecules. In contrast to the threshold spectra of two-atomic molecules, where were exist more or less defined structures of excited states, as well as vibrational levels, in the threshold spectra of triatomic molecules clearly defined structures almost do not exist. The application of the expert system in the process of triatomic and polyatomic molecules spectra analysis has an important role because it enables analysis of larger number of excited states, vibrational levels, and resonances, which can be missed in the analysis by classical methods, either because of low intensity or because of insufficiently defined separation of peaks in spectrum, which arise from the overlapping of a large number of peaks. [ABSTRACT FROM AUTHOR]

I briefly review recent QCD Sum Rules determinations of the strange current quark mass, based on the analysis of the two-point δS = 1 scalar correlators and discuss, in particular, the role of resonances and non-resonant background in the spectral function. I briefly review recent QCD Sum Rules determinations of the strange current quark mass, based on the analysis of the two-point δS = 1 scalar correlators and discuss, in particular, the role of resonances and non-resonant background in the spectral function. [ABSTRACT FROM AUTHOR]