Electron-Molecule and Photon-Molecule Collisions pp 173-182 | Cite as

# Improved Hybrid Theory Calculation of e-N_{2} Vibrational Excitation

## Abstract

I will describe some new calculations on e^{−}-N_{2} vibrational excitation using hybrid theory. When we did our original calculations^{1} and obtained vibrational excitation cross sections, we were faced with the problem that some upper-atmospheric physicists at Goddard actually wanted to use them; they wanted accurate normalized vibrational excitation cross sections. I would have liked to advise them to use the experimental results; unfortunately, the experimental normalizations are not as yet unique. The situation is demonstrated in Figure 1. The curves on the left are essentially Schulz’s original ones.^{2} They were differential cross sections measured at 72° as a function of energy and the normalization was arbitrary. However, assuming the total cross sections had the same shape as a function of energy (and this is an excellent approximation“), Schulz pointed out that if you use the values (in Å^{2}) given on the ordinate, Figure la, then you get agreement with previous experimental results of Haas.^{3} Subsequently, Schulz^{4} renormalized these curves based on later absolute measurements of Spence et al.^{5} which is given in Figure lb, and you see they are a factor of two larger. In the same article^{4} Schulz also showed a figure based on work that S. F. Wong has done which, after conversion to total cross section using our dσ/dΩ gives a normalization yet another factor of two larger. In fact, that normalization in Figure lc is almost identical to what Chandra and I got in our original hybrid calculation^{1} But in view of the other normalizations, as well as uncertainties in our calculation, I could only advise caution to our atmospheric colleagues and promise them a better calculation. What I’d like to describe here is a preliminary report of this new calculation.

## Keywords

Total Cross Section Differential Cross Section Partial Wave Vibrational Excitation Elastic Cross Section## Preview

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## References

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