scholarly journals Thermal Inelastic Collision Processes

1958 ◽  
Vol 8 ◽  
pp. 979-991
Author(s):  
M. J. Seaton
Keyword(s):  
Cross Sections ◽  
Inelastic Collision ◽  
Heavy Particle ◽  
Inelastic Collisions ◽  
Impact Excitation ◽  
Semiempirical Methods ◽  
Particle Collisions ◽  
Exchange Reactions ◽  
Proton Impact ◽  
Collision Processes

Section II contains a summary of relevant collision theory methods. Section III is concerned with heavy particle collisions: excitation of H 1s hyperfine structure (hfs) states by H atom impact; excitation of H2 rotation by H and H2 impact; H 2s→2p transitions produced by proton impact; charge exchange reactions; excitation of atomic levels by proton impact. Section IV deals with inelastic collisions between atoms and electrons. Use of the Born and distorted wave approximations is discussed. Calculations of cross sections for excitation of forbidden lines in pq configurations are reviewed and new results presented for O+2, N+, C+, and Si+, both variational and semiempirical methods being used. In Sec. V, concerned with atomic photoionization, new results are given for photoionization from 2pq configurations.

Working Group 3: Collision Processes

1988 ◽  
Vol 20 (1) ◽  
pp. 123-128
Author(s):  
A. Dalgarno
Keyword(s):  
Working Group ◽  
Heavy Particle ◽  
Atomic Data ◽  
Particle Collisions ◽  
Vast Array ◽  
Recent Developments ◽  
Group 3 ◽  
Collision Processes ◽  
Astronomical Research

Of the vast array of data on electron and heavy-particle collisions that are produced each year, I select only those that have an obvious immediate bearing on astronomical research. A brief review of recent developments in atomic data for astrophysics has been published (1).

scholarly journals Forbidden transitions in excitation by proton impact in Li-like Al ions

2007 ◽  
Vol 25 (2) ◽  
pp. 277-282 ◽  
Author(s):  
V. Stancalie ◽  
V. Pais ◽  
M. Totolici ◽  
A. Mihailescu
Keyword(s):  
Cross Sections ◽  
Born Approximation ◽  
High Energy ◽  
Impact Excitation ◽  
Proton Impact ◽  
Collision Strength ◽  
Energy Behavior ◽  
Forbidden Transitions ◽  
Excitation Processes ◽  
The Impact

This paper presents cross-sections and collision strengths for proton-impact excitation of optically forbidden transitions in Al10+. These data, calculated in the impact-parameter formalism, covering the expected range of energies/temperature in laser-produced plasmas, are believed to represent the first such detailed treatment of this system. The cross-sections decrease with energy as E−1, while the collision strengths tend to finite limits as the energy of colliding proton becomes infinitely great. This high-energy limiting value has been evaluated combining results from the semi-classical treatment of ion-impact excitation processes and the Born approximation for high-energy behavior of the collision strength. The effective target size has been estimated from the calculated high-energy limit of the collision strength in the Born approximation.

Energy loss of protons passing through hydrogen

1955 ◽  
Vol 232 (1190) ◽  
pp. 423-434 ◽  
Keyword(s):  
Experimental Data ◽  
Energy Loss ◽  
Total Energy ◽  
Detailed Analysis ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Heavy Particle ◽  
Stopping Power ◽  
Particle Collisions ◽  
Hydrogen Atoms

The cross-sections of processes involving protons and hydrogen atoms calculated by Bates, Dalgarno and Griffing using the Bom approximation are employed to make a detailed analysis of the contributions of excitation, ionization and capture to the stopping power of a gas of atomic hydrogen for a beam consisting initially of protons. A range of beam energies from 10 keV to 3 MeV is covered. The computed total energy loss is compared with experimental data and the accuracy of the Bom approximation for heavy particle collisions is discussed.

Observation of Partial Wave Resonances in Low-Energy O2–H2 Inelastic Collisions

Science ◽  
2013 ◽  
Vol 341 (6150) ◽  
pp. 1094-1096 ◽  
Author(s):  
Simon Chefdeville ◽  
Yulia Kalugina ◽  
Sebastiaan Y. T. van de Meerakker ◽  
Christian Naulin ◽  
François Lique ◽  
...  
Keyword(s):  
Partial Wave ◽  
Cross Sections ◽  
Ground State ◽  
Total Angular Momentum ◽  
Inelastic Collisions ◽  
Quantum Mechanical ◽  
Quantum Scattering ◽  
Rotational Excitation ◽  
Collision Processes ◽  
Theoretical Results

Partial wave resonances predicted to occur in bimolecular collision processes have proven challenging to observe experimentally. Here, we report crossed-beam experiments and quantum-scattering calculations on inelastic collisions between ground-state O2 and H2 molecules that provide state-to-state cross sections for rotational excitation of O2 (rotational state N = 1, j = 0) to O2 (N = 1, j = 1) in the vicinity of the thermodynamic threshold at 3.96 centimeter−1. The close agreement between experimental and theoretical results confirms the classically forbidden character of this collision-induced transition, which occurs exclusively in a purely quantum mechanical regime via shape and Feshbach resonances arising from partial waves with total angular momentum (J) = 2 to 4.

The 1 s -2 s excitation of hydrogen atoms by proton impact

1960 ◽  
Vol 258 (1293) ◽  
pp. 237-244 ◽  
Keyword(s):  
Interaction Energy ◽  
Cross Sections ◽  
Impact Excitation ◽  
Hydrogen Atoms ◽  
Third Order ◽  
Proton Impact ◽  
The Third ◽  
Intermediate States ◽  
The Cross ◽  
Approximation Calculation

It is shown that the cross-sections given by the customary second Born approximation are not reliable because of the neglect of a large term of the fourth order in the interaction energy. The expression for the cross-section obtained by including only terms to the third order in the interaction energy is employed to calculate the cross-sections for the proton impact excitation of the 2 s state of atomic hydrogen, allowance being made for distortion and polarization due to the 1 s , 2 s and 2 p 0.±1 intermediate states. When polarization is ignored by neglecting all terms involving the 2 p states, excellent agreement is found with the distortion approximation calculation of Bates.

Sign in / Sign up

Export Citation Format

Share Document