Ladungsaustausch zwischen Ionen und Atomen der Edelgase bei Stoßenergien unterhalb 200 eV

1969 ◽  
Vol 24 (11) ◽  
pp. 1716-1720
Author(s):  
H. Schlumbohm
Keyword(s):  
Cross Section ◽  
Charge Exchange ◽  
Cross Sections ◽  
Collision Energy ◽  
Threshold Energy ◽  
Strong Increase ◽  
Published Data ◽  
Slow Ions ◽  
Endothermic Process ◽  
The Cross

Charge exchange cross sections for the four systems He+, Ne+ + Ar, Kr have been measured, ap­plying slow ions gathering techniques. The values are several 1O-16 cm2 and are almost constant between 20 and 200 eV collision energy. The comparison with previously published data for charge exchange into optically excited higher states of the ions show that these reactions prefer at least at 25 to 30% endothermic channels instead of the exothermic one without excitation. - Additionally the cross section of the endothermic process Ar++Ne was measured. Above a threshold energy of 17 eV it shows a strong increase and a constant value of 7 · 10-17 cm2 between 20 and 200 eV.

scholarly journals Investigating Scalar Unparticle Production at Collisions with Polarized Beams in Unparticle Physics

2020 ◽  
Vol 36 (4) ◽  
Author(s):  
Le Nhu Thuc ◽  
Dao Thi Le Thuy
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Z Boson ◽  
Collision Energy ◽  
High Energy ◽  
Polarized Beams ◽  
Boson Exchange ◽  
The Cross ◽  
Muon Colliders ◽  
Energy Frontier

Scalar unparticle production in the process is studied from unparticle physics perspective. We have calculated and evaluated the cross sections for muon and Z boson exchange when the  beams are initially polarized. Numerical calculations show that the cross section of collisions depends strongly on the polarized condition of the initial beams and the collision energy . The results are plotted in the energy reach available at the present accelerators and the future high energy frontier muon colliders as shown in the scheme by Muon Accelerator Program (MAP) and other different colliders.

Processus non réactifs dans les collisions H2 + H(2s) aux énergies thermiques

1990 ◽  
Vol 68 (2) ◽  
pp. 206-213
Author(s):  
B. Stern
Keyword(s):  
Ab Initio Calculations ◽  
Ab Initio ◽  
Cross Section ◽  
Cross Sections ◽  
Differential Rotation ◽  
Collision Energy ◽  
Close Coupling ◽  
Interference Phenomenon ◽  
The Cross ◽  
Energy Surfaces

Ab initio calculations of energy surfaces of the system [Formula: see text] corresponding to dissociation into H(2s) + H2 (X, 1Σg+) and H(2p0) + H2(X) are presented. For a thermal collision energy (0,064 eV), multistate close-coupling calculations are performed. In relation to experiments in progress, elastic and inelastic differential rotation cross sections are shown. For the quenching of H(2s) by H2:[Formula: see text]the cross section is obtained from an interference phenomenon between the elastic amplitudes associated to the two molecular states related to the entrance and exit channels, respectively. After criticizing the models used for the collision, which are valid only for small scattering angles, improvements are proposed in conclusion.[Journal translation]

scholarly journals Laser Assisted Charge Exchange in Atomic Collisions

1991 ◽  
Vol 11 (3-4) ◽  
pp. 285-290 ◽  
Author(s):  
J. F. Castillo ◽  
L. F. Errea ◽  
L Méndez ◽  
A. Riera
Keyword(s):  
Cross Section ◽  
Charge Exchange ◽  
Cross Sections ◽  
Laser Field ◽  
Laser Wavelength ◽  
Total Charge ◽  
Atomic Collisions ◽  
Radiative Transitions ◽  
The Cross ◽  
Impact Energies

We present total charge exchange cross sections for collisions of Li(1s22s2S) with H(1s) in presence of a linear polarized laser field of intensity 0.05 ≤ I ≤ 1 TW/cm2 and wavelength 5 103 ≤ λ ≤ 14 103 Å. Our calculation shows that the laser field can increase the cross section of this reaction by a factor of ten at impact energies E < 0.1 ke V/a.m.u. The mechanism of this process is discussed and it is shown that both atomic and molecular radiative transitions can take place depending on the laser wavelength employed.

Cross sections for the 93Nb(n,2n)92mNb reaction

1990 ◽  
Vol 68 (7-8) ◽  
pp. 582-586 ◽  
Author(s):  
D. C. Santry ◽  
R. D. Werner
Keyword(s):  
Cross Section ◽  
Neutron Spectrum ◽  
Cross Sections ◽  
Threshold Energy ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
Transfer Standard ◽  
Fission Neutron Spectrum ◽  
Maximum Value ◽  
The Cross

The cross section of the 93Nb(n,2n)92mNb reaction has been studied by use of the activation method from the threshold energy of 8.8–19.8 MeV. Measurements are relative to the known cross-section values for the reactions H(n,n)H, 32S(n,p)32p, and 27Al(n,α)24Na. The cross-section value increases smoothly with energy and reaches a maximum value of 444 ± 18 mb at about 14.5 MeV then decreases to values of 293 ± 14 mb at 19.8 MeV. An effective cross-section value for a fission neutron spectrum calculated from the results is 0.321 ± 0.019 mb. The activation of Nb as a transfer standard for 14 MeV neutrons is discussed.

Messung der Streuquerschnitte von flüssigem und festem Wasserstoff, Deuterium und Deuteriumhydrid für thermische Neutronen

1970 ◽  
Vol 25 (6) ◽  
pp. 967-972 ◽  
Author(s):  
W. D. Seiffert ◽  
B. Weckermann ◽  
R. Misenta
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Solid Phase ◽  
Threshold Energy ◽  
Rotational Level ◽  
Para Hydrogen ◽  
Hydrogen Deuterium ◽  
Normal Hydrogen ◽  
The Cross ◽  
Deuterium Hydride

Abstract The total cross section for thermal neutrons of liquid and solid normal-hydrogen, para-hydrogen, deuterium and deuterium hydride have been measured at several temperatures. The cross section of the liquid and solid phase of para-hydrogen shows that the para-hydrogen molecule scatters coherently. The coherence effects in the cross sections of liquid para-hydrogen and deuterium indicate a short range order of the molecules in the liquid. The cross sections of para-hydrogen and deuterium hydride show clearly the excitation of the first rotational level of the molecule. The threshold indicates that the molecules of the liquid phase are not completely free. The cross section of liquid and solid para-hydrogen for neutrons with energies larger than the threshold energy show a different behaviour that can be explained by the different dynamics of liquid and solid.

scholarly journals Dissoziation von H2+ und H3+ beim Stoß an Kr im Energiebereich 6 – 60 keV / Dissociation of H2+ and H3+ by Collision with Kr in the Energy Range between 6 to 60 keV

1976 ◽  
Vol 31 (11) ◽  
pp. 1303-1307 ◽  
Author(s):  
B. Lehmann
Keyword(s):  
Radio Frequency ◽  
Energy Range ◽  
Cross Section ◽  
Charge Exchange ◽  
Cross Sections ◽  
Ion Source ◽  
Energy Curve ◽  
Gas Target ◽  
The Cross

Abstract H2+ and H3+ ions, produced in a H2 plasma of a radio-frequency ion source, were accelerated to 6-60 keV and directed into a gas target of Krypton. The cross sections for the formation of H+ and H- resp. H2+, H+ and H- have been measured. In the case of H+, obtained from the dissociation of H2+, 2 maxima have been found in the present energy range. A third is known to be at about 100 keV. We discuss the applicability of the Massey' adiabatic hypothesis, known from the analysis of charge-exchange experiments, to the maxima in the cross-section vs. energy curve for dissociation experiments.

Experimental Studies Of Multilayer Glass Structures On Compression, Compression With Bending And Simple Bending

2019 ◽  
pp. 22-30
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Applied Load ◽  
Experimental Studies ◽  
Strength Properties ◽  
Research Topic ◽  
Normative Values ◽  
Laminated Glass ◽  
The Cross ◽  
Experimental Values

The work of multilayer glass structures for central and eccentric compression and bending are considered. The substantiation of the chosen research topic is made. The description and features of laminated glass for the structures investigated, their characteristics are presented. The analysis of the results obtained when testing for compression, compression with bending, simple bending of models of columns, beams, samples of laminated glass was made. Overview of the types and nature of destruction of the models are presented, diagrams of material operation are constructed, average values of the resistance of the cross-sections of samples are obtained, the table of destructive loads is generated. The need for development of a set of rules and guidelines for the design of glass structures, including laminated glass, for bearing elements, as well as standards for testing, rules for assessing the strength, stiffness, crack resistance and methods for determining the strength of control samples is emphasized. It is established that the strength properties of glass depend on the type of applied load and vary widely, and significantly lower than the corresponding normative values of the strength of heat-strengthened glass. The effect of the connecting polymeric material and manufacturing technology of laminated glass on the strength of the structure is also shown. The experimental values of the elastic modulus are different in different directions of the cross section and in the direction perpendicular to the glass layers are two times less than along the glass layers.

scholarly journals Total cross sections of eγ → $$ eX\overline{X} $$ processes with X = μ, γ, e via multiloop methods

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Roman N. Lee ◽  
Alexey A. Lyubyakin ◽  
Vyacheslav A. Stotsky
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Elliptic Integral ◽  
High Energy ◽  
Calculation Methods ◽  
Complete Elliptic Integral ◽  
Total Cross Sections ◽  
Multiloop Calculation ◽  
The Cross ◽  
Analytical Expressions

Abstract Using modern multiloop calculation methods, we derive the analytical expressions for the total cross sections of the processes e−γ →$$ {e}^{-}X\overline{X} $$ e − X X ¯ with X = μ, γ or e at arbitrary energies. For the first two processes our results are expressed via classical polylogarithms. The cross section of e−γ → e−e−e+ is represented as a one-fold integral of complete elliptic integral K and logarithms. Using our results, we calculate the threshold and high-energy asymptotics and compare them with available results.

scholarly journals Asymptotic Behavior of Stable Structures Made of Beams

2021 ◽  
Author(s):  
Georges Griso ◽  
Larysa Khilkova ◽  
Julia Orlik ◽  
Olena Sivak
Keyword(s):  
Asymptotic Behavior ◽  
Cross Section ◽  
Cross Sections ◽  
Linear Elasticity ◽  
Circular Cross Section ◽  
Linear Elasticity Theory ◽  
Linear Elastic ◽  
The Cross ◽  
Small Rotation ◽  
Stable Structures

AbstractIn this paper, we study the asymptotic behavior of an $\varepsilon $ ε -periodic 3D stable structure made of beams of circular cross-section of radius $r$ r when the periodicity parameter $\varepsilon $ ε and the ratio ${r/\varepsilon }$ r / ε simultaneously tend to 0. The analysis is performed within the frame of linear elasticity theory and it is based on the known decomposition of the beam displacements into a beam centerline displacement, a small rotation of the cross-sections and a warping (the deformation of the cross-sections). This decomposition allows to obtain Korn type inequalities. We introduce two unfolding operators, one for the homogenization of the set of beam centerlines and another for the dimension reduction of the beams. The limit homogenized problem is still a linear elastic, second order PDE.

ISOSPIN DECOMPOSITION OF pp → NNππ CROSS SECTIONS — DO WE SEE A SIGN OF Δ(1600) EXCITATION IN THE nnπ+π+ CHANNEL?

2009 ◽  
Vol 24 (02n03) ◽  
pp. 450-453
Author(s):  
◽  
T. SKORODKO ◽  
M. BASHKANOV ◽  
D. BOGOSLOWSKY ◽  
H. CALÉN ◽  
...  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Pion Production ◽  
Significant Contribution ◽  
Differential Cross Sections ◽  
Pp Collisions ◽  
Theoretical Predictions ◽  
Order Of Magnitude ◽  
The Cross

The two-pion production in pp-collisions has been investigated in exclusive measurements from threshold up to Tp = 1.36 GeV . Total and differential cross sections have been obtained for the channels pnπ+π0, ppπ+π-, ppπ0π0 and also nnπ+π+. For intermediate incident energies Tp > 1 GeV , i.e. in the region, which is beyond the Roper excitation but at the onset of ΔΔ excitation the total ppπ0π0 cross section falls behind theoretical predictions by as much as an order of magnitude near 1.2 GeV, whereas the nnπ+π+ cross section is a factor of five larger than predicted. A model-unconstrained isospin decompostion of the cross section points to a significant contribution of an isospin 3/2 resonance other than the Δ(1232). As a possible candidate the Δ(1600) is discussed.

Sign in / Sign up

Export Citation Format

Share Document