Excitation of singly-ionized barium ions by electron impact

1970 ◽  
Vol 48 (3) ◽  
pp. 275-278 ◽  
Author(s):  
J. Davis ◽  
S. Morin
Keyword(s):  
Energy Range ◽  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Experimental Measurements ◽  
Barium Ions ◽  
Semiclassical Method ◽  
The Cross

We present cross-section calculations for excitation of singly-ionized barium ions by electron impact over the energy range from 3 to 100 eV. The cross sections were evaluated using Burgess' semiclassical method. Finally, our predictions are compared with two other current techniques and some recent experimental measurements. The agreement was found to be good.

Absolute cross sections for D2 Lyman and Werner band excitation by controlled electron impact

1984 ◽  
Vol 62 (1) ◽  
pp. 1-9 ◽  
Author(s):  
K. Becker ◽  
J. W. McConkey
Keyword(s):  
Energy Range ◽  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Impact Energy ◽  
Emission Cross Section ◽  
Direct Excitation ◽  
The Cross ◽  
Impact Energies

We have studied the Lyman [Formula: see text] and Werner [Formula: see text] band emissions produced by 20–500-eV electrons incident on molecular deuterium, D2. Emission cross sections of (3.7 ± 0.9) × 10−17 cm2 for the B → X and (3.54 ± 0.74) × 10−17 cm2 for the C → X system have been determined at 100-eV impact energy. Cascading did not play an important role in the [Formula: see text] emission, but it was shown to affect the [Formula: see text] emission seriously, particularly for impact energies below 50 eV. We estimate the cross section for direct excitation of the [Formula: see text] state and the cascade cross section to be 2.95 × 10−17 and 0.75 × 10−17 cm2, at 100 eV respectively. The cascade cross section is 20 ± 10% of the total B → X emission cross section, and is essentially constant in the energy range 300–50 eV, but increases significantly for lower impact energies, e.g., to 40 ± 15% at 27.5 eV. The cross section for the atomic 2p → 1s Lyman α emission from D2 has also been measured and the value of 1.00 × 10−17 cm2 at 100 eV is 20% smaller than the cross section for Lyman α emission from H2.

DOUBLE PION PHOTOPRODUCTION EXPERIMENT AT LNS–TOHOKU

2008 ◽  
Vol 23 (27n30) ◽  
pp. 2313-2316 ◽  
Author(s):  
◽  
H. KANDA ◽  
N. CHIGA ◽  
Y. FUJII ◽  
K. FUTATSUKAWA ◽  
...  
Keyword(s):  
Total Cross Section ◽  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Pion Photoproduction ◽  
Total Cross Sections ◽  
Free Proton ◽  
Double Pion ◽  
The Cross

The total cross sections for the π+π− photoproduction on the deuteron were measured in an energy range of 0.8 to 1.1 GeV. The obtained total cross section for the quasi-free π+π− photoproduction on the deuteron was about 60 % of those on the free proton. The cross section for Δ++Δ− photoproduction was derived from the non-quasi-free π+π− photoproduction events. It was smaller than the previous data.

scholarly journals Cross Section Ionization By Electron Impact Of Helium Like Ions

2021 ◽  
Author(s):  
Manel Hariz Belgacem ◽  
Elhabib Guedda ◽  
Haikel Jelassi
Keyword(s):  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Ground State ◽  
The Cross ◽  
State 1 ◽  
Unstable States ◽  
Good Agreement

<sub></sub> In this paper we present our calculation of the cross section ionization by electron impact of C V, N VI and O VII. Using the Flexible Atomic Code (FAC), we obtain the cross sections for the ionization of these ions from the ground state 1<sup>1</sup>S, and from the unstable states 2<sup>1</sup>S and 2<sup>3</sup>S. Our results are in good agreement with those based on the Coulomb Born (CB) approximation and the available measurements.

scholarly journals Differential Cross Sections of 9Be(d,p0)10Be, 9Be(d,p1)10Be, 9Be(d,α0)7Li and 9Be(d,α1)7Li reactions

2019 ◽  
Vol 26 ◽  
pp. 151
Author(s):  
P. Tsavalas ◽  
A. Lagoyannis ◽  
K. Mergia ◽  
E. Ntemou ◽  
C. P. Lungu
Keyword(s):  
Elastic Scattering ◽  
Energy Range ◽  
Nuclear Reaction ◽  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Areal Density ◽  
Deuteron Energy ◽  
Nuclear Reaction Analysis ◽  
The Cross

In the present work, the cross sections of the 9Be(d,p0)10Be, 9Be(d,p1)10Be,9Be(d,α0)7Li and 9Be(d,α1)7Li in the deuteron energy range Elab= 1 – 2.2 MeV with an energy step of 20 keV and at detection angles between 120o and 170o were measured, suitable for nuclear reaction analysis. A Si3N4film coated with a thin Be layer was used and the cross sections are determined relatively to the cross section of the natSi(d,d)natSi elastic scattering. Additionally, proton and oxygen beam measurements were carried out in order to determine the atomic areal density which is required to determine the cross sections.

scholarly journals Twist-3 contributions to $$\gamma \gamma \rightarrow \pi ^+\pi ^-,K^+K^-$$ processes in perturbative QCD approach

2019 ◽  
Vol 79 (9) ◽  
Author(s):  
Cong Wang ◽  
Jun-Kang He ◽  
Ming-Zhen Zhou
Keyword(s):  
Perturbative Qcd ◽  
Cross Section ◽  
Cross Sections ◽  
Degrees Of Freedom ◽  
Intermediate Energy ◽  
Angular Distributions ◽  
Experimental Measurements ◽  
Belle Ii ◽  
The Cross ◽  
Near Future

Abstract As one of the simplest hadronic processes, $$\gamma \gamma \rightarrow M^{+}M^{-}$$γγ→M+M- ($$M=\pi ,K$$M=π,K) could be a good testing ground for our understanding of the perturbative and nonperturbative structure of QCD, and will be studied with high precision at BELLE-II in the near future. In this paper, we revisit these processes with twist-3 corrections in the perturbative QCD approach based on the $$k_{T}$$kT factorization theorem, in which transverse degrees of freedom as well as resummation effects are taken into account. The influence of the distribution amplitudes on the cross sections are discussed in detail. Our work shows that not only the transverse momentum effects but also the twist-3 corrections play a significant role in the processes $$\gamma \gamma \rightarrow M^{+}M^{-}$$γγ→M+M- in the intermediate energy region. Especially in the few GeV region, the twist-3 contributions become dominant in the cross sections. And it is noteworthy that both the twist-3 result of the $$\pi ^{+}\pi ^{-}$$π+π- cross section and that of the $$K^{+}K^{-}$$K+K- cross section agree well with the BELLE and ALEPH measurements. For the pion and kaon angular distributions, there still exist discrepancies between our results and the experimental measurements. Possible reasons for these discrepancies are discussed briefly.

scholarly journals Corrigendum

2020 ◽  
Vol 18 (1) ◽  
pp. 75-75
Author(s):  
E Editorial
Keyword(s):  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Impact Excitation ◽  
Rate Coefficients ◽  
Electron Impact Excitation ◽  
Ordinate Axis ◽  
The Cross ◽  
Font Color ◽  
Corrected Figure

The Editor-in-Chief has been informed that in the article ?Comparisons of Quantemol and Morgan LXCat cross section sets for electron-neutral scattering and rate-coefficients: helium and water?, FACTA UNIVERSITATIS, Series Physics, Chemistry and Technology Vol. 17, No 2, 2019, pp. 145-159, DOI: https://doi.org/10.2298/FUPCT1902145M, the cross sections for electron-impact excitation of helium in Figure 1b) are wrongly presented. The values of the cross section in the ordinate axis are marked in the interval from 10-1 to 101 (in units 10-16 cm2), and should be from 10-2 to 100. We apologize for that oversight. After further discussion with the corresponding author, the Editor-in-Chief has decided to publish a corrigendum with corrected Figure 1. Link to the corrected article: https://doi.org/10.2298/FUPCT1902145M <br><br><font color="red"><b> Link to the corrected article <u><a href="http://dx.doi.org/10.2298/FUPCT1902145M">10.2298/FUPCT1902145M</a></b></u>

scholarly journals The 55Mn(p,?)56Fe and 55Mn(p,n)55Fe Cross Sections

1983 ◽  
Vol 36 (1) ◽  
pp. 1 ◽  
Author(s):  
LW Mitchell ◽  
DG Sargood
Keyword(s):  
Statistical Model ◽  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Reaction Rates ◽  
Significant Part ◽  
Thermonuclear Reaction ◽  
Model Calculations ◽  
The Cross

The cross section of the reaction 55Mn(p, y)56Pe has been measured in the energy range 0�80-2�04 MeV and of the reaction 55Mn(p, n)55Pe from threshold to 2� 04 MeV. Statistical model calculations reproduce the (p, n) cross section to within a factor of 1� 4, but with the (p, y) reaction they fail by a factor ;;;:2 over a significant part of the energy range. Thermonuclear reaction rates are calculated from the data for temperatures in the range (1-5) x 109 K.

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.

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