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.

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.

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.

Measurement of absolute electron-impact excitation cross sections in Ar and N2 using H and H2 emissions as secondary standards

1988 ◽  
Vol 66 (4) ◽  
pp. 349-357 ◽  
Author(s):  
J. L. Forand ◽  
S. Wang ◽  
J. M. Woolsey ◽  
J. W. McConkey
Keyword(s):  
Electron Impact ◽  
Cross Section ◽  
Cross Sections ◽  
Emission Cross Section ◽  
Impact Excitation ◽  
Electron Impact Excitation ◽  
Dissociative Excitation ◽  
Excitation Cross Sections ◽  
Line Following ◽  
Good Agreement

A detailed description is given of a technique in which emissions from H and H2 are used to calibrate an apparatus used for electron-impact emission cross-section measurements in the wavelength range 90–130 nm. Absolute emission cross sections have been measured at 200 eV electron-impact energy for the 120 nm N I line following dissociative excitation of N2 and for the Ar and Ar+ lines at 104.8, 106.7, 92.0, and 93.8 nm respectively. Good agreement with earlier works is obtained in the case of the N I line when earlier data are renormalized to take into account the recent revision of the cross section for production of Lyman α from H2. Measurements of the 104.8 and 106.7 nm lines suggest a 40% cascade component for the latter line at energies of 200 eV and above.

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 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.

scholarly journals Production of O(1D) following electron impact on CO2

2013 ◽  
Vol 91 (12) ◽  
pp. 1044-1048 ◽  
Author(s):  
W. Kedzierski ◽  
J.D. Hein ◽  
C.J. Tiessen ◽  
D. Lukic ◽  
J.A. Trocchi ◽  
...  
Keyword(s):  
Energy Range ◽  
Electron Impact ◽  
Cross Sections ◽  
Impact Energy ◽  
Production Cross ◽  
Threshold Energy ◽  
Dissociative Excitation ◽  
Pulsed Electron Beam ◽  
Exciting Electron ◽  
Relative Production

We have studied the excitation of metastable O(1D) following dissociative excitation of CO2 in the electron impact energy range from threshold to 400 eV. A solid Ne matrix at ∼20 K forms the heart of the detector. This is sensitive to the metastable species through the formation of excited excimers (NeO*), The resultant excimer radiation is readily detected, providing a means of measuring the production of the metastables. Using a pulsed electron beam and time-of-flight techniques, we have measured the O(1D) kinetic energy spectrum and its relative production cross sections as a function of electron impact energy. Threshold energy data are used to gain information about the excitation channels involved. In addition, an emission excitation function for the red photons, emitted in coincidence with the exciting electron pulse, has been measured in the 0–400 eV energy range.

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>

Ionization in collisions between 30–1000 keV antiprotons and atomic hydrogen

1996 ◽  
Vol 74 (7-8) ◽  
pp. 490-495 ◽  
Author(s):  
K. Paludan ◽  
H. Knudsen ◽  
U. Mikkelsen ◽  
M. Charlton ◽  
K. Kirsebom ◽  
...  
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Theoretical Calculations ◽  
Published Data ◽  
Ionization Cross ◽  
Ionization Cross Sections ◽  
Impact Energies ◽  
Theoretical Results

Recently published data for impact of antiprotons in the energy range 30–1000 keV on atomic hydrogen are compared with analogous proton, electron, and positron measurements, and it is found that the ionization cross sections of atomic hydrogen follow the same pattern as similar cross sections obtained on He and H2 targets, in accordance with the general phenomenological description of single ionization that has developed over the last decade. Further comparisons are made with various recent and advanced theoretical calculations for antiproton ionization of atomic hydrogen. These theoretical results agree well with the data obtained, but for lower impact energies the different methods do not, despite the simplicity of the system, agree on predicting even the form of the cross section.

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