Articles | Volume 41, issue 2
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11 Sep 2023
Regular paper | Highlight paper |  | 11 Sep 2023

Analysis of in situ measurements of electron, ion and neutral temperatures in the lower thermosphere–ionosphere

Panagiotis Pirnaris and Theodoros Sarris

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Cited articles

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The research presented in this paper includes a large number of events during which the neutral temperatures were higher than the ion temperatures. This feature is against what we know from textbooks, suggesting that further investigations on this issue should be performed.
Short summary
The relation between electron, ion and neutral temperatures in the lower thermosphere–ionosphere (LTI) is key to understanding the energy balance and transfer between species. However, their simultaneous measurement is rare in the LTI. Based on data from the AE-C, AE-D, AE-E and DE-2 satellites of the 1970s and 1980s, a large number of events where neutrals are hotter than ions are identified and statistically analyzed. Potential mechanisms that could trigger these events are proposed.