scholarly journals Theoretical vibrational-excitation cross sections and rate coefficients for electron-impact resonant collisions involving rovibrationally excited N2and NO molecules

2012 ◽  
Vol 21 (5) ◽  
pp. 055018 ◽  
Author(s):  
V Laporta ◽  
R Celiberto ◽  
J M Wadehra
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Vibrational Excitation ◽  
Rate Coefficients ◽  
Excitation Cross Sections

scholarly journals Rotational and Vibrational Excitation of Nitrogen by Electron Impact

1997 ◽  
Vol 50 (3) ◽  
pp. 441 ◽  
Author(s):  
A. G. Robertson ◽  
M. T. Elford ◽  
R. W. Crompton ◽  
Michael A. Morrison ◽  
Weiguo Sun ◽  
...  
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Unsolved Problem ◽  
Vibrational Excitation ◽  
Rotational Excitation ◽  
Early Analysis ◽  
Excitation Cross Sections ◽  
Low Energy Electron ◽  
Experimental Values ◽  
Best Fit

Rotational excitation of nitrogen by low-energy electron impact has posed an unsolved problem for more than three decades. Early analysis of the results of swarm experiments in nitrogen found that the data could be matched remarkably well by assuming that the energy dependences of the Δj = 2 cross sections from threshold to a few tenths of an eV are given by a simple formula based on the Born approximation. Moreover, the quadrupole moment (the only adjustable parameter in the formula) which gave the best fit to the data was commensurate with existing experimental values. This finding posed an enigma, since the quadrupole Born expression is known to incorrectly represent the interaction potential for scattering except within a few meV of threshold. We have analysed new swarm data, taken in a dilute mixure of nitrogen in neon, using theoretical rotational and momentum transfer cross sections based on a solution of the Schrödinger equation using static, exchange, and polarisation potentials. This work explains the long-standing enigma and provides the basis for a subsequent analysis in which theoretical vibrational excitation cross sections are also investigated using the new swarm data for the mixture.

Vibrational excitation cross sections forF2by electron impact

1986 ◽  
Vol 34 (2) ◽  
pp. 1568-1570 ◽  
Author(s):  
Y. Fujita ◽  
S. Yagi ◽  
S. S. Kano ◽  
H. Takuma ◽  
T. Ajiro ◽  
...  
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Vibrational Excitation ◽  
Excitation Cross Sections

scholarly journals Excitations of the nS States of Atomic Hydrogen by Electron Impact, Excitation Rate Coefficients, and Phase Shifts: Comparison with Positron Impact Excitation

Atoms ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 5
Author(s):  
Anand K. Bhatia
Keyword(s):  
Electron Impact ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Phase Shifts ◽  
Impact Excitation ◽  
Rate Coefficients ◽  
Orbital Method ◽  
Positron Impact ◽  
Excitation Rate ◽  
Excitation Cross Sections

The excitation cross-sections of the nS states of atomic hydrogen, n = 2 to 6, by electron impact on the ground state of atomic hydrogen were calculated using the variational polarized-orbital method at various incident electron energies in the range 10 to 122 eV. Converged excitation cross-sections were obtained using sixteen partial waves (L = 0 to 15). Excitation cross-sections to 2S state, calculated earlier, were calculated at higher energies than before. Results obtained using the hybrid theory (variational polarized orbital method) are compared to those obtained using other approaches such as the Born–Oppenheimer, close-coupling, R-matrix, and complex-exterior scaling methods using only the spherical symmetric wave functions. Phase shifts and elastic cross-sections are given at various energies and angular momenta. Excitation rate coefficients were calculated at various electron temperatures, which are required for plasma diagnostics in solar and astrophysics to infer plasma parameters. Excitation cross-sections are compared with those obtained by positron impact excitation.

Sign in / Sign up

Export Citation Format

Share Document