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  • Quantum Calculation of the Vibrational Excitation of Nitrogen Molecules by Fast Ions: Can It Contribute to STEVE Formation?
Title: Quantum Calculation of the Vibrational Excitation of Nitrogen Molecules by Fast Ions: Can It Contribute to STEVE Formation?
Abstract The vibrational‐translational (VT) excitation of nitrogen molecules led by collisions with fast ions in subauroral ion drifts (SAID) has been conceived as a potential underlying mechanism contributing to the formation of the Strong Thermal Emission Velocity Enhancement (STEVE) phenomenon (Harding et al., 2020,https://doi.org/10.1029/2020gl087102). In this study, we perform quantum calculations of the VT excitation rates of N2led by fast‐drifting ions, and evaluate the resulting vibrational distribution of N2with ionospheric/thermospheric parameters expected under intense SAID condition. We conclude that, while the VT energy transfer led by SAID plays a distinguishable role in the vibrational excitation of N2, it is incapable of populating the high vibrational levels to the required concentration (Harding et al., 2020,https://doi.org/10.1029/2020gl087102) to produce adequate nitric oxide density, and in turn the nitrogen‐dioxide continuum intensity, to account for the STEVE brightness.  more » « less
Award ID(s):
2445467
PAR ID:
10674359
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
51
Issue:
17
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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