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The structural properties and radial distributions of the valence electron in different excited levels of Na atom (n = 3–5, l = 0–4; n and l being the principal and orbital angular momentum quantum numbers, respectively) under impenetrable spherical confinement have been studied, where the interaction between the frozen core and the valence electron is mimicked by a model potential available in the literature. The effect of the core on the valence electron has been investigated by estimating the structural properties of Na10+ ion under similar confinement. Scaled radial densities at the nucleus and related ratios are presented for a few excited states of the valence electron of Na atom and the corresponding analytic results have been tested numerically.

We present an analysis of the physical and dynamical states of two sets of EAGLE zoom simulations of galaxy haloes, one at high redshift ($z=2-3$) and the other at low redshift ($z=0$), with masses of $\approx 10^{12} M_{\odot}$. Our focus is how the circumgalactic medium (CGM) of these $L^*$ star-forming galaxies change over the last 10 Gyr. We find that the high-$z$ CGM is almost equally divided between the "cool" ($T, 16 pages, 15 figures. Submitted to MNRAS. Comments welcome. (revision submitted on May 22, 2020 fixes Fig. 3. right panel that mistakenly displayed metal mass and now correctly displays total gas mass)

Molecular dynamics simulations of benzene and 12 fluorobenzenes with various degrees of fluorine substitution in water reveal that the accumulation of water in the first solvent shell decreases with increase in number of fluorine atoms relative to benzene, with an exception of hexafluorobenzene. Further, the solute–solute radial density function indicates that partially substituted fluorobenzenes sample $$ \uppi $$-stacked and T-shaped geometries. In contrast benzene and hexafluorobenzene sample only the T-shaped geometries. Comparison of solute–solute and solute–solvent radial density functions suggests that solute–solute interactions is preferred over solute–solvent interaction, which suggests the hydrophobic nature of fluorobenzenes, which increases with increase in number of fluorine atoms on the phenyl ring. The spatial distribution of water around the fluorobenzenes suggests that water avoids the C–F bond group, which indicates increase in hydrophobicity of fluorobenzenes with number of fluorine atoms.

The full-field moisture-induced strains (in-plane) and Z-displacements (out-of-plane) of the different tissues of tamarack and red oak woods were assessed by three-dimensional digital image correlation (3D-DIC). Swelling strains in tangential (Ɛxx) and radial (Ɛyy) directions and Z-displacements in axial direction were measured on the cross section of wood samples from dried condition below P2O5 to moisture adsorption condition at 20 °C and 90% RH. Global swelling coefficients (α) were calculated and compared with 3D-DIC strains. Ɛxx, Ɛyy, and Z-displacement data were extracted from earlywood (EW) and latewood (LW) of tamarack, and from three tissue zones of red oak: large vessel zone of the earlywood (EW-v), fiber-dominated (LW-Fiber) and axial parenchyma-dominated (LW-Pa) zones of the latewood. The localized full-field strains were matched with density data obtained by X-ray densitometry. Tamarack wood had a homogeneous Ɛxx, while different Ɛyys were observed for EW and LW. Red oak wood had a more complex mapping of full-field strains, in which the effects of the broad rays on Ɛxx and differences between tissues on Ɛyy appear. A discussion about the radial density profile data and the full-field strains at the tissue level as well as the anisotropic behavior of different tissues is presented for both species. An opposite behavior was found for the EW and LW of tamarack in the longitudinal direction (Z-displacement), showing that EW swells and LW shrinks after moisture adsorption. For red oak, EW-v also swelled and LW-Fiber shrank in the longitudinal direction. LW-Pa zone also shrank after adsorption but to a lower degree.

Although the assumption of elliptical symmetry is quite common in multivariate analysis and widespread in a number of applications, the problem of testing the null hypothesis of ellipticity so far has not been addressed in a fully satisfactory way. Most papers in the literature indeed are dealing with the null hypothesis of elliptical symmetry with specified location and actually address location rather than non-elliptical alternatives. In this paper, we are proposing new classes of testing procedures, both for specified and unspecified location. The backbone of our construction is Le Cam’s asymptotic theory of statistical experiments, and optimality is to be understood locally and asymptotically within the family of generalized skew-elliptical distributions. The tests we are proposing are enjoying all the desirable properties of a “good” test of elliptical symmetry: they have simple asymptotic distributions under the entire null hypothesis of elliptical symmetry with unspecified radial density and shape parameter; they are affine-invariant, computationally fast, intuitively understandable, and not too demanding in terms of moments. While achieving optimality against generalized skew-elliptical alternatives, they remain quite powerful under a much broader class of non-elliptical distributions and significantly outperform the available competitors.

The molecular radial density ( ρ rad ) serves as a powerful tool to partition molecules into: non-bonding, core, and bonding regions. Similar to ρ rad , a method is presented where both forms of the radial kinetic, exchange, Coulomb, and electron-nuclear potential energy densities are plotted on a mesh. As far as we are aware, this is the first time expressions for energy densities have been presented. Such plots provide an alternative approach to understanding the physics and chemistry of molecular properties and make it possible to partition molecular energies into atomic and bonding regions (ABIM) using any weighting function.

Birch and spruce samples were scanned using X-ray computed tomography (CT) to determine changes in the density and density profile caused by thermo-hydro treatment (THT). Small-dimension wood blocks were subjected to treatment at three different temperatures (160 degrees C, 170 degrees C and 180 degrees C) for 1 h and scanned before and after treatment. Identical acquisition and analysis procedures were used to evaluate the changes in approximate mean density and radial density profile of oven-dried untreated and treated material. The X-ray CT scans enabled measuring of the changes in wood density after THT. The results confirm that there were similar tendencies in the total density decrease with increasing temperature. However, variations in density changes between the earlywood (EW) and latewood (LW) of birch and spruce were found. A correlation of the radial density profiles of treated versus untreated specimens showed a similar density decrease in EW and LW in birch wood and inconsistent reductions in spruce wood.

Sodium imaging typically employs ultrashort echo time radial, density adapted and cones trajectories to capture the rapidly decaying short T2 signal. The present study considers the parameter choices involved in the use of these trajectories in terms of their impact on the resolution and signal to noise ratio. Many parameters have a strong effect on these image properties, particularly the number of spokes which impacts voxel size. The present article develops an understanding of the trade-offs involved and how to choose optimal (or at least reasonable) parameter values. This has a practical role in designing clinical protocols for imaging sodium.

This paper presents a study of the interaction between Alfvén modes and zonal structures, considering a realistic ASDEX Upgrade equilibrium. The results of gyrokinetic simulations with the global, electromagnetic, particle-in-cell code ORB5 are presented, where the modes are driven unstable by energetic particles with a bump-on-tail equilibrium distribution function, with radial density gradient. Two regimes have been observed. At low energetic particle concentration, the zonal structure (identified as an energetic particle-driven geodesic acoustic mode) is more unstable than the Alfvén mode. In the regime at high energetic particle concentration, the Alfvén mode is more unstable than the zonal structure. The interplay between the modes leads to a modification of their growth rates as well as to a modification of their saturation levels. The theoretical explanation of the mode interaction is given in terms of three-wave coupling of the energetic particle-driven geodesic acoustic mode and Alfvén mode, mediated by the curvature–pressure coupling term of the energetic particles.

We propose the numerical method for determining the radius of a star cluster using its radial surface density profile. The method realizes the algorithm of an eye estimate but minimizes a subjectivity; its result is in a good agreement with the eye estimate of the radius for the open cluster NGC 2516.

Experiments at the GOL-PET facility have shown that injection of a relativistic electron beam at kiloampere current into a magnetized plasma column with strong radial density gradients is accompanied by generation of THz radiation flux which power estimated at the level of several megawatts. Extraction of this flux along the axis of the beam-plasma system is essentially increased in case when the end of the plasma column is separated by a vacuum gap from the wall of a plasma chamber. Results of measuring the spatial and angular properties of such megawatt flux of THz radiation going out from the plasma to an air of the experimental hall are described in our paper.

Observations of X-ray absorption lines in magnetically driven disk winds around black hole binaries and active galactic nuclei yield a universal radial density profile rho proportional to r^{-1.2} in the wind. This is in disagreement with the standard Blandford & Payne profile rho_BP proportional to r^{-1.5} expected when the magnetic field is neither advected nor diffusing through the accretion disk. In order to account for this discrepancy, we establish a new paradigm for magnetically driven astrophysical winds according to which the large scale ordered magnetic field that threads the disk is continuously generated by the Cosmic Battery around the inner edge of the disk and continuously diffuses outward. We obtain self-similar solutions of such magnetically advected winds (MAW) and discuss their observational ramifications., 5 pages, 1 figures, accepted for publication in Monthly Notices Letters

We study the isoperimetric problem for the axially symmetric sets in the Heisenberg group $$\mathbb {H}^n$$ with density $$|z|^p$$ . At first, we prove the existence of weighted isoperimetric sets. Then, we characterize weighted isoperimetric sets uniquely as bubble sets. Finally, we deduce an interesting result that, up to a constant multiplicator, $$|z|^p$$ is the only horizontal radial density for which bubble sets can be weighted isoperimetric sets.

We show that in superfluids with fermionic imbalance and uniform ground state, there are stable solitons. These solutions are formed of radial density modulations resulting in nodal rings. We demonstrate that these solitons exhibit nontrivial soliton-soliton and soliton-vortex interactions and can form complicated bound states in the form of "soliton sacks". In a phase-modulating (Fulde-Ferrell) background, we find different solitonic states, in the form of stable vortex-antivortex pairs., Version published in Physical Review Research

A scenario for the formation of the bi-modality in the chemical space [$\alpha$/Fe] vs [Fe/H] of the Milky Way was recently proposed in which $\alpha$-enhanced stars are produced early and quickly in clumps. Besides accelerating the enrichment of the medium with $\alpha$-elements, these clumps scatter the old stars, converting in-plane to vertical motion, forming a geometric thick disc. In this paper, by means of a detailed analysis of the data from smooth particle hydrodynamical simulations, we investigate the geometric properties (in particular of the chemical thick disc) produced in this scenario. For mono-age populations we show that the surface radial density profiles of high-[$\alpha$/Fe] stars are well described by single exponentials, while that of low-[$\alpha$/Fe] stars require broken exponentials. This break is sharp for young populations and broadens for older ones. The position of the break does not depend significantly on age. The vertical density profiles of mono-age populations are characterized by single exponentials, which flare significantly for low-[$\alpha$/Fe] stars but only weakly (or not at all) for high-[$\alpha$/Fe] stars. For low-[$\alpha$/Fe] stars, the flaring level decreases with age, while for high-[$\alpha$/Fe] stars it weakly increases with age (although with large uncertainties). All these properties are in agreement with observational results recently reported for the Milky Way, making this a plausible scenario for the formation of the Galactic thick disc., Comment: 11 pages, 12 figures; Updated to published (MNRAS) version - inclusion of extra references and minor changes suggested by the referee

We report the discovery of four new open clusters (named as QC 1, QC 2, QC3 and QC 4) in the direction of Cygnus Cloud and select their members based on five astrometric parameters (l, b, \varpi, \mu^*_{\alpha}, \mu_{\delta}) of Gaia DR2. We also derive their astrophysical parameters for each new cluster. Structure parameters are generated by fitting the radial density distribution with King's profile. Using solar metallicity, we performed isochrone-fitting on their purified color-magnitude diagrams (CMDs) to achieve the age of the clusters. The known cluster NGC 7062 at adjacent area is chosen to verify our identification process. The estimated distance, reddening and age of NGC 7062 are in good agreement with the literature., Comment: 10 pages, 4 figures, 3 tables. Accepted for publication in Research in Astronomy and Astrophysics

The circumgalactic medium (CGM) of the Milky Way is mostly obscured by nearby gas in position-velocity space because we reside inside the Galaxy. Substantial biases exist in most studies on the Milky Way's CGM that focus on easier-to-detect high-velocity gas. With mock observations on a Milky-Way analog from the FOGGIE simulation, we investigate four observational biases related to the Milky Way's CGM. First, QSO absorption-line studies probe a limited amount of the CGM mass: only 35% of the mass is at high Galactic latitudes $|b|>20$ degrees, of which only half is moving at $|v_{\rm LSR}|\gtrsim100$ km s$^{-1}$. Second, the inflow rate ($\dot{M}$) of the cold gas observable in HI 21cm is reduced by a factor of $\sim10$ as we switch from the local standard of rest to the galaxy's rest frame; meanwhile $\dot{M}$ of the cool and warm gas does not change significantly. Third, OVI and NV are promising ions to probe the Milky Way's outer CGM ($r\gtrsim$15 kpc), but CIV may be less sensitive. Lastly, the scatter in ion column density is a factor of 2 higher if the CGM is observed from inside-out than from external views because of the gas radial density profile. Our work highlights that observations of the Milky Way's CGM, especially those using HI 21cm and QSO absorption lines, are highly biased. We demonstrate that these biases can be quantified and calibrated through synthetic observations with simulated Milky-Way analogs., ApJ in press

We quantify the performance of mass mapping techniques on mock imaging and gravitational lensing data of galaxy clusters. The optimum method depends upon the scientific goal. We assess measurements of clusters' radial density profiles, departures from sphericity, and their filamentary attachment to the cosmic web. We find that mass maps produced by direct (KS93) inversion of shear measurements are unbiased, and that their noise can be suppressed via filtering with MRLens. Forward-fitting techniques, such as Lenstool, suppress noise further, but at a cost of biased ellipticity in the cluster core and over-estimation of mass at large radii. Interestingly, current searches for filaments are noise-limited by the intrinsic shapes of weakly lensed galaxies, rather than by the projection of line-of-sight structures. Therefore, space-based or balloon-based imaging surveys that resolve a high density of lensed galaxies, could soon detect one or two filaments around most clusters., Comment: 19 pages, 10 figures, updated to match MNRAS version

We aim to characterize the physical and chemical properties of fragmented cores during the earliest evolutionary stages in the very young star-forming regions ISOSS J22478+6357 and ISOSS J23053+5953. NOEMA 1.3 mm data are used in combination with archival mid- and far-infrared observations to construct and fit the SEDs of individual fragmented cores. The radial density profiles are inferred from the 1.3 mm continuum visibility profiles and the radial temperature profiles are estimated from H2CO rotation temperature maps. Molecular column densities are derived with the line fitting tool XCLASS. The physical and chemical properties are combined by applying the physical-chemical model MUSCLE in order to constrain the chemical timescales of a few line-rich cores. The morphology and spatial correlations of the molecular emission are analyzed using the HOG method. The mid-infrared data show that both regions contain a cluster of young stellar objects. Bipolar molecular outflows are observed in the CO 2-1 transition toward the strong mm cores indicating protostellar activity. We find strong molecular emission of SO, SiO, H2CO, and CH3OH in locations which are not associated with the mm cores. These shocked knots can be either associated with the bipolar outflows or, in the case of ISOSS J23053+5953, with a colliding flow that creates a large shocked region between the mm cores. The mean chemical timescale of the cores is lower (20 000 yr) compared to that of the sources of the more evolved CORE sample (60 000 yr). With the HOG method, we find that the spatial emission of species tracing the extended emission and of shock-tracing molecules are well correlated within transitions of these groups., 34 pages, 17 figures, accepted for publication in A&A

The density distribution over the radius of porous permeable hollow cylinder produced by radial isostatic compacting is analyzed and calculated. The factors promoting an inhomogeneous density distribution in porous permeable materials during this type of compacting are determined by analytical calculations. It is proved that the optimal pore distribution across the section of porous permeable material providing maximum operating properties can be obtained by using the compacting procedure that allows relating the structural properties of the material with principal operating modes.

An exploration of the parameter space available for the supercritical water assembly is performed. Geometry and materials selection will be examined. The material selection will be limited to the structural materials because oxide fuels were assumed and enrichment was set to provide a critical assembly. Steels were found to reduce the k eff of the system. Analysis of the results led to the investigation of radial density variation. It is found that a 57.3651 pcm reactivity change occured with radial density variation across 2 × 10 −4 m. This implies that fully 3D thermohydraulic analysis is required for accurate modeling of supercritical water reactors.

We extract void catalogs from the Sloan Digital Sky Survey Data Release 16 (SDSS DR16) survey and also from the Millennium simulation. We focus our comparison on distribution of galaxies brighter than $M_r < -18$ inside voids and study the mean separation of void galaxies, distance from the void center, and the radial density profile. We find that mean separation of void galaxies depends on void size, as bigger voids have lower mean separation in both samples. However, void galaxies in the observation sample seem to have generally larger mean-distance than simulated ones at any given void size. In addition, observed void galaxies tend to reside closer to the void center than those in the simulation. This discrepancy is also shown in the density profile of voids. Regardless of the void size, the central densities of real void profiles are higher than the ones in the predicted simulated catalog.

The effects of temperature and pressure on the adsorption capacity of vanadium oxide nanotube (VONT) were investigated by Monte Carlo (MC) simulation. Hydrogen adsorption was an increasing function...

By considering the anisotropic pressure tensor, two separate equations of state (EoS) as functions of the density, temperature, and carbon nanotube (CNT) diameter have been proposed for the radial and axial directions for the confined Lennard-Jones (LJ) fluid into (11,11), (12,10), and (19,0) CNTs from 120 to 600 K using molecular dynamics (MD) simulations. We have also investigated the effects of the pore size, pore loading, chirality, and temperature on some of the structural and dynamical properties of the confined LJ fluid into (11,11), (12,10), (19,0), and (19,19) CNTs such as the radial density profile and self-diffusion coefficient. We have also determined the EoS for the confined LJ fluid into double and triple walled CNTs.

We obtain exact analytic expressions for (i) the electromagnetic energy radial density within and outside a multilayered sphere and (ii) the total electromagnetic energy stored within its core and each of its shells. Explicit expressions for the special cases of lossless core and shell are also provided. The general solution is based on compact recursive transfer-matrix method and its validity includes also magnetic media. The theory is illustrated on the examples of electric field enhancement within various metallo-dielectric silica-gold multilayered spheres. User-friendly MATLAB code which includes the theoretical treatment, is available as a supplement to the paper., 11 pages, 2 figures