The magnetic-sublevel population of the autoionization state formed in dielectronic recombination (DR) of highly charged heavy ions has been experimentally investigated by combining two types of measurements with an e...
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The magnetic-sublevel population of the autoionization state formed in dielectronic recombination (DR) of highly charged heavy ions has been experimentally investigated by combining two types of measurements with an electron beam ion trap. The two different measurements are the differential x-ray measurement at 90∘ with respect to the electron beam and the integral resonance-strength measurement. The alignment parameter, which denotes the magnetic-sublevel population distribution, has been obtained for the autoionization states [1s2s22p1/2]1 formed in DR of Li-like Pr (atomic number Z=59) and Ho (Z=67). This work is a complement to our previous work [Phys. Rev. Lett. 108, 073002 (2012)] on Li-like Au (Z=79). The experimental results are in reasonable agreement with theoretical predictions, and a strong Z-dependent tendency due to the Breit interaction has been confirmed.
We survey the early history of the discovery of quark gluon plasma and the early history of the Universe, beginning with the present day and reaching deep into QGP and almost beyond. We introduce cosmological Universe...
We survey the early history of the discovery of quark gluon plasma and the early history of the Universe, beginning with the present day and reaching deep into QGP and almost beyond. We introduce cosmological Universe dynamics and connect the different Universe epochs with one another. We describe some of the many remaining open questions that emerge.
This paper studies a class of probabilistic models on graphs, where edge variables depend on incident node variables through a fixed probability kernel. The class includes planted constraint satisfaction problems (CSP...
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We assess the validity of various exchange-correlation functionals for computing the structural, vibrational, dielectric, and thermodynamical properties of materials in the framework of density-functional perturbation...
We assess the validity of various exchange-correlation functionals for computing the structural, vibrational, dielectric, and thermodynamical properties of materials in the framework of density-functional perturbation theory (DFPT). We consider five generalized-gradient approximation (GGA) functionals (PBE, PBEsol, WC, AM05, and HTBS) as well as the local density approximation (LDA) functional. We investigate a wide variety of materials including a semiconductor (silicon), a metal (copper), and various insulators (SiO2 α-quartz and stishovite, ZrSiO4 zircon, and MgO periclase). For the structural properties, we find that PBEsol and WC are the closest to the experiments and AM05 performs only slightly worse. All three functionals actually improve over LDA and PBE in contrast with HTBS, which is shown to fail dramatically for α-quartz. For the vibrational and thermodynamical properties, LDA performs surprisingly very well. In the majority of the test cases, it outperforms PBE significantly and also the WC, PBEsol and AM05 functionals though by a smaller margin (and to the detriment of structural parameters). On the other hand, HTBS performs also poorly for vibrational quantities. For the dielectric properties, none of the functionals can be put forward. They all (i) fail to reproduce the electronic dielectric constant due to the well-known band gap problem and (ii) tend to overestimate the oscillator strengths (and hence the static dielectric constant).
The radiative transfer equation (RTE) arises in a variety of applications. The equation is challenging to solve numerically for a couple of reasons: high dimensionality, integro-differential form, highly forward-peake...
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We generate jammed disordered packings of 100≤N≤2000 monodisperse hard spheres in three dimensions whose strictly jammed backbones are demonstrated to be exactly isostatic with unprecedented numerical accuracy. This...
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We generate jammed disordered packings of 100≤N≤2000 monodisperse hard spheres in three dimensions whose strictly jammed backbones are demonstrated to be exactly isostatic with unprecedented numerical accuracy. This is accomplished by using the Torquato-Jiao (TJ) packing algorithm as a means of studying the maximally random jammed (MRJ) state. The rattler fraction of these packings converges towards 0.015 in the infinite-system limit, which is markedly lower than previous estimates for the MRJ state using the Lubachevsky-Stillinger protocol. This is because the packings that the TJ algorithm creates are closer to the true MRJ state, as shown using bond-orientational and translational order metrics. The rattler pair correlation statistics exhibit strongly correlated behavior contrary to the conventional understanding that they be randomly (Poisson) distributed. Dynamically interacting “polyrattlers” may be found imprisoned in shared cages as well as interacting through “bottlenecks” in the backbone and these clusters are mainly responsible for the sharp increase in the rattler pair correlation function near contact. We discover the surprising existence of polyrattlers with cluster sizes of up to five rattlers (which is expected to increase with system size) and present a distribution of polyrattler occurrence as a function of cluster size and system size. We also enumerate all of the rattler interaction topologies we observe and present images of several examples, showing that MRJ packings of monodisperse spheres can contain large rattler cages while still obeying the strict jamming criterion. The backbone spheres that encage the rattlers are significantly hypostatic, implying that correspondingly hyperstatic regions must exist elsewhere in these isostatic packings. We also observe that rattlers in hard-sphere packings share an apparent connection with the low-temperature two-level system anomalies that appear in real amorphous insulators and semiconductors.
Motivated by the work of R. G. McClarren, C. D. Hauck, and R. B. Lowrie on a filtered spherical harmonic method, we present a new filter for such numerical approximations to the multi-dimensional transport equation. I...
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ISBN:
(纸本)9781627486439
Motivated by the work of R. G. McClarren, C. D. Hauck, and R. B. Lowrie on a filtered spherical harmonic method, we present a new filter for such numerical approximations to the multi-dimensional transport equation. In several test problems, we demonstrate that the new filter produces results with significantly less Gibbs phenomena than the filter used by McClarren, Hauck and Lowrie. This reduction in Gibbs phenomena translates into propagation speeds that more closely match the correct propagation speed and solutions that have fewer regions where the scalar flux is negative.
Source iteration is a iterative process usually used to solve the particle transport problem. For physical system containing subregions that are optically thick and scattering-dominated, most of the particles undergo ...
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Source iteration is a iterative process usually used to solve the particle transport problem. For physical system containing subregions that are optically thick and scattering-dominated, most of the particles undergo many collisions before being captured or leaking out, source iteration is inefficient and costly. In this paper,
We theoretically investigate the high-order above-threshold ionization (HATI) of an atom in an infrared (IR) and extreme ultraviolet (XUV) two-color laser field, where the XUV photon energy is much larger than the ato...
We theoretically investigate the high-order above-threshold ionization (HATI) of an atom in an infrared (IR) and extreme ultraviolet (XUV) two-color laser field, where the XUV photon energy is much larger than the atomic ionization *** HATI spectrum presents a multi-plateau structure, where the height of each plateau is determined by how many XUV photons is absorbed by the *** analyzing the XUV multi-photon quantum channels, we find that the ionized electron can collide with its parent ion elastically and ***, in the non-elastic channel, the ionized electron absorbs XUV photons during the collision, which cannot be explained by the classical three-step *** results indicate that the previously established concept that "HATI is an elastic recollision process" breaks down.
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