Kinetic energy spectra in thermionic emission from small tungsten cluster anions: Evidence for nonclassical electron capture

2010 ◽  
Vol 132 (10) ◽  
pp. 104307 ◽  
Author(s):  
Bruno Concina ◽  
Bruno Baguenard ◽  
Florent Calvo ◽  
Christian Bordas
Keyword(s):  
Kinetic Energy ◽  
Electron Capture ◽  
Thermionic Emission ◽  
Energy Spectra ◽  
Cluster Anions

Kinetic energy spectra of divergent wind in the atmosphere

Tellus ◽  
1981 ◽  
Vol 33 (1) ◽  
pp. 102-104 ◽  
Author(s):  
Tsing-Chang Chen ◽  
Joseph J. Tribbia
Keyword(s):  
Kinetic Energy ◽  
Energy Spectra ◽  
Divergent Wind

Turbulent kinetic energy spectra and cascades in the polar atmosphere of Saturn

2021 ◽  
Author(s):  
Peter L. Read ◽  
Arrate Antuñano ◽  
Simon Cabanes ◽  
Greg Colyer ◽  
Teresa del Rio-Gaztelurrutia ◽  
...  
Keyword(s):  
Kinetic Energy ◽  
High Latitude ◽  
Deep Convection ◽  
Baroclinic Instability ◽  
Polar Vortex ◽  
Energy Spectra ◽  
Horizontal Wind ◽  
Polar Regions ◽  
Zonal Wavenumber ◽  
Cloud Tops

<p>The regions of Saturn’s cloud-covered atmosphere polewards of 60<sup>o</sup> latitude are dominated in each hemisphere near the cloud tops by an intense, cyclonic polar vortex surrounded by a strong, high latitude eastward zonal jet. In the north, this high latitude jet takes the form of a remarkably regular zonal wavenumber m=6 hexagonal pattern that has been present at least since the Voyager spacecraft encounters with Saturn in 1980-81, and probably much longer. The origin of this feature, and the absence of a similar feature in the south, has remained poorly understood since its discovery. In this work, we present some new analyses of horizontal wind measurements at Saturn’s cloud tops polewards of 60 degrees in both the northern and southern hemispheres, previously published by Antuñano et al. (2015) using images from the Cassini mission, in which we compute kinetic energy spectra and the transfer rates of kinetic energy (KE) and enstrophy between different scales. 2D KE spectra are consistent with a zonostrophic regime, with a steep (~n<sup>-5</sup>) spectrum for the mean zonal flow (n is the total wavenumber) and a shallower Kolmogorov-like KE spectrum (~n<sup>-5/3</sup>) for the residual (eddy) flow, much as previously found for Jupiter’s atmosphere (Galperin et al. 2014; Young & Read 2017). Three different methods are used to compute the energy and enstrophy transfers, (a) as latitude-dependent zonal spectral fluxes, (b) as latitude-dependent structure functions and (c) as spatially filtered energy fluxes. The results of all three methods are largely in agreement in indicating a direct (forward) enstrophy cascade across most scales, averaged across the whole domain, an inverse kinetic energy cascade to large scales and a weak direct KE cascade at the smallest scales. The pattern of transfers has a more complex dependence on latitude, however. But it is clear that the m=6 North Polar Hexagon (NPH) wave was transferring KE into its zonal jet at 78<sup>o</sup> N (planetographic) at a rate of ∏<sub>E</sub> ≈ 1.8 x 10<sup>-4</sup> W kg<sup>-1</sup> at the time the Cassini images were acquired. This implies that the NPH was not maintained by a barotropic instability at this time, but may have been driven via a baroclinic instability or possibly from deep convection. Further implications of these results will be discussed.</p><p> </p><p>References</p><p>Antuñano, A., T. del Río-Gaztelurrutia, A. Sánchez-Lavega, and R. Hueso (2015), Dynamics of Saturn’s polar regions, J. Geophys. Res. Planets, 120, 155–176, doi:10.1002/2014JE004709.</p><p>Galperin, B., R. M.B. Young, S. Sukoriansky, N. Dikovskaya, P. L. Read, A. J. Lancaster & D. Armstrong (2014) Cassini observations reveal a regime of zonostrophic macroturbulence on Jupiter, Icarus, 229, 295–320.doi: 10.1016/j.icarus.2013.08.030</p><p>Young, R. M. B. & Read, P. L. (2017) Forward and inverse kinetic energy cascades in Jupiter’s turbulent weather layer, Nature Phys., 13, 1135-1140. Doi:10.1038/NPHYS4227</p><div> <div> <div> </div> </div> <div> <div> </div> </div> <div> <div> </div> </div> <div> <div> </div> </div> </div>

scholarly journals Сечения образования ионов He-=SUP=-+-=/SUP=- в различных электронных состояниях при столкновениях ионов He-=SUP=-2+-=/SUP=- с атомами водорода

2020 ◽  
Vol 90 (6) ◽  
pp. 895
Author(s):  
А.А. Басалаев ◽  
В.В. Кузьмичев ◽  
М.Н. Панов ◽  
О.В. Смирнов
Keyword(s):  
Kinetic Energy ◽  
Electron Capture ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Precision Measurements ◽  
Capture Cross ◽  
Hydrogen Atoms ◽  
Hydrogen Target ◽  
Degree Of Dissociation ◽  
Capture Cross Sections

Using collision spectroscopy based on precision measurements of the kinetic energy of projectile ions that capture an electron, we measured the state selective electron capture cross sections of formation of He^+(n) ions at collision 3^He^{2 +} ions with an energy of E = 1.4-10 keV/a.m.u. with hydrogen atoms. The atomic hydrogen target with a degree of dissociation 78% at a temperature of tungsten dissociation cell 2180K has been made.

Rearrangements in the Molecular Ions of Some ortho-Substituted Schiff Bases

1993 ◽  
Vol 46 (6) ◽  
pp. 895 ◽  
Author(s):  
T Blumenthal ◽  
M Dosen ◽  
RG Gillis ◽  
QN Porter
Keyword(s):  
Kinetic Energy ◽  
Schiff Bases ◽  
Molecular Ions ◽  
Energy Spectra ◽  
Supporting Evidence ◽  
Deuterium Labelling ◽  
Methyl Group ◽  
Molecular Ion ◽  
Fragment Ions ◽  
Ion Kinetic Energy

Under electron ionization conditions, the ortho-substituted Schiff bases N-benzylidene-o-toluidine (1a), N-(o-methylbenzylidene)aniline (1b), N-salicylideneaniline (1c) and N-(o-methoxybenzylidene)aniline (1d) give fragment ions which have been shown by collision-activated mass-analysed ion kinetic energy spectra to have the structure of the protonated molecular ions of indole (2), benzofuran (3), and 1,2-benzisoxazole (4). The molecular ion of N-(o-methylbenzylidene)-o-toluidine (1f) gives as fragment ions not only the protonated molecular ion (2) of indole and the tropylium ion but also the molecular ion of anthracene. Attempts to find supporting evidence for a mechanism for this rearrangement by deuterium labelling of a methyl group in (1b), such as (1g), have been unsuccessful.

Angle-dependence of ion kinetic energy spectra obtained by using mass spectrometers II. Experimental considerations and preliminary results on non-fragmenting systems

1984 ◽  
Vol 392 (1802) ◽  
pp. 89-106 ◽  
Keyword(s):  
Kinetic Energy ◽  
Energy Analysis ◽  
Energy Spectra ◽  
Observation Angle ◽  
Initial Angle ◽  
Mass Spectrometers ◽  
Small Uncertainty ◽  
Ion Kinetic Energy ◽  
Double Focusing ◽  
Selection Of

Experimental problems associated with studies of the scattering of kilovolt projectile ions in mass spectrometers designed primarily for chemical analysis are discussed. The parameters that are important in satisfactorily controlling and defining the actual scattering angle in relation to the observation angle are considered in detail. Two different experimental configurations are considered; angular selection before, or after kinetic energy analysis of the collision products. A modification to a VG ZAB-2F double-focusing mass spectrometer, in order to observe angle-resolved ion kinetic energy spectra of collisionally scattered ion beams, is described. Initial angle-resolved experiments on systems that do not involve fragmentation, have been performed. The results are presented for the angle-resolved energy loss spectra of Ar + and N 2 + and the angle-resolved charge-stripping of Ar + . A feature of the apparatus described is the small uncertainty in the angular selection of the analysing angle-resolved slit.

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