Joan Basset, a poet active in the early 15th century, wrote his Vers clus around 1415-1416. This enigmatic composition presents an allegorical confrontation between two factions of monstrous figures, led respectively by a dragon and a Turk. Basset’s use of allegory can be explained by the need to disguise a politically charged message in a particularly tense socio-political context at the end of the Western Schism, as well as by an aesthetic tradition that valued poetry of formal and thematic complexity. This article offers a contextualised interpretation of the Vers clus, considering the political events of its time and the literary tradition that frames it. The poem emerges as a work in which political reality is conveyed through symbol.
In this work, we present a theoretical study of the photoionization for atomic hydrogen confined in onion fullerene compared with the bare H atom and the single fullerene case. We obtained the expected confinement resonances for the integrated probabilities, finding different trends for the main peak and the first ATI peak integrations. We perform these calculations with a recently developed methodology using Generalized Sturmian Functions to numerically solve the time-dependent Schrödinger equation.
The process of wave propagation in an infinite linear chain is analyzed. Established, that dispersion relation between the angular frequency and the wave number for transverse waves differs from similar dependencies for longitudinal.
A simple prototypical model of aromatic pi-pi stacking system -- benzene sandwich dimer is investigated by ab initio calculations based on second-order Moller-Plesset perturbation theory (MP2) and Minnesota hybrid functional M06-2X.
The results for binding energies of $^6$Li He$_2$ and $^7$Li He$_2$ systems are presented. They are obtained by solving Faddeev equations in configuration space. It is shown that the excited states in both systems are of the Efimov-type.
H. Bahcivan, J. W. Cutler, J. C. Springmann
et al.
The second Radio Aurora Explorer (RAX‐2) satellite has completed more than 30 conjunction experiments with the Advanced Modular Incoherent Scatter Radar chain of incoherent scatter radars in Alaska and Resolute Bay, Canada. Coherent radar echoing occurred during four of the passes: three when E region electron drifts exceeded the ion acoustic speed threshold and one during HF heating of the ionosphere by the High Frequency Active Auroral Research Program heater. In this paper, we present the results for the first three passes associated with backscatter from natural irregularities. We analyze, in detail, the largest drift case because the plasma turbulence was the most intense and because the corresponding ground‐to‐space bistatic scattering geometry was the most favorable for magnetic aspect sensitivity analysis. A set of data analysis procedures including interference removal, autocorrelation analysis, and the application of a radar beam deconvolution algorithm mapped the distribution of E region backscatter with 3 km resolution in altitude and ∼0.1° in magnetic aspect angle. To our knowledge, these are the highest resolution altitude‐resolved magnetic aspect sensitivity measurements made at UHF frequencies in the auroral region. In this paper, we show that despite the large electron drift speed of ∼1500 m/s, the magnetic aspect sensitivity of submeter scale irregularities is much higher than previously reported. The root‐mean‐square of the aspect angle distribution varied monotonically between 0.5° and 0.1° for the altitude range 100–110 km. Findings from this single but compelling event suggest that submeter scale waves propagating at larger angles from the main E×B flow direction (secondary waves) have parallel electric fields that are too small to contribute to E region electron heating. It is possible that anomalous electron heating in the auroral electrojet can be explained by (a) the dynamics of those submeter scale waves propagating in the E×B direction (primary waves) or (b) the dynamics of longer wavelengths.
Large horizontal winds and wind shears have been measured in the lower thermosphere by rockets, lidars, and nonspecular meteor radars. This paper describes a detailed analysis of three multihour nonspecular meteor radar data sets collected at the Jicamarca Radio Observatory. This provides some of the highest‐resolution sustained measurements in this part of the atmosphere. These show (1) intense wind speeds, maintaining 180 m/s for half an hour and 160 m/s for another half an hour; (2) winds structured in layers that move up or, more commonly, down in the predawn hours at rates of a few kilometers per hour; (3) intense wind shears that typically persist at around 50 m/s/km but, in one instance, sustains values approaching 100 m/s/km for a few hours.
A diagnostic pressure equation constraint has been incorporated into a storm-scale three-dimensional variational (3DVAR) data assimilation system. This diagnostic pressure equation constraint (DPEC) is aimed to improve dynamic consistency among different model variables so as to produce better data assimilation results and improve the subsequent forecasts. Ge et al. (2012) described the development of DPEC and testing of it with idealized experiments. DPEC was also applied to a real supercell case, but only radial velocity was assimilated. In this paper, DPEC is further applied to two real tornadic supercell thunderstorm cases, where both radial velocity and radar reflectivity data are assimilated. The impact of DPEC on radar data assimilation is examined mainly based on the storm forecasts. It is found that the experiments using DPEC generally predict higher low-level vertical vorticity than the experiments not using DPEC near the time of observed tornadoes. Therefore, it is concluded that the use of DPEC improves the forecast of mesocyclone rotation within supercell thunderstorms. The experiments using different weighting coefficients generate similar results. This suggests that DPEC is not very sensitive to the weighting coefficients.
Using Li clusters, a prototype of simple metals, as a test case, we theoretically find that metal clusters can mimic the behavior of simple molecules in electronic shells. It is found that Li14, Li10, and Li8 clusters are exact analogues of F2, N2, and CH4 molecules.
Bosonic atom-trimer scattering is studied in the unitary limit using momentum-space equations for four-particle transition operators. The impact of the Efimov effect on the atom-trimer scattering observables is explored and a number of universal relations is established. Positions and widths of tetramer resonances are determined. Trimer relaxation rate constant is calculated.
Dressed states of spinor Bose-Einstein condensates of spin-1 atoms located in optical cavity of near resonance frequency of excited state of the atom are investigated. The wave function of dark states are given.
An evaluation of slow neutrons deceleration through their interaction with nanoclusters in liquid helium is performed. It is shown that process is strongly suppresed if the clusters are bound by the van der Waals interaction.
The paper addresses counterintuitive behavior of electrons injected into dense cryogenic media with negative scattering length $a_0$. Instead of expected polaronic effect (formation of density enhancement clusters) which should substantially reduce the electron mobility, an opposite picture is observed: with increasing $|a_0|$ (the trend taking place for inert gases with the growth of atomic number) and the medium density, the electrons remain practically free. An explanation of this behaviour is provided based on consistent accounting for the non-linearity of electron interaction with the gaseous medium in the gas atom number density.
Recent reports on intense-field pump-probe experiments for high harmonic generation from coherently rotating linear molecules, have revealed remarkable characteristic effects of the simultaneous variation of the polarization geometry and the time delay on the high harmonic signals. We analyze the effects and give a unified theoretical account of the experimental observations
Elena A. Kolganova, Alexander K. Motovilov, Werner Sandhas
We review results on scattering observables for $^4$He--$^4$He$_2$ and $^3$He--$^4$He$_2$ collisions. We also study the effect of varying the coupling constant of the atom-atom interaction on the scattering length.