STEVE and the Picket Fence: Evidence of Feedback‐Unstable Magnetosphere‐Ionosphere Interaction. Issue 24 (23rd December 2019)
- Record Type:
- Journal Article
- Title:
- STEVE and the Picket Fence: Evidence of Feedback‐Unstable Magnetosphere‐Ionosphere Interaction. Issue 24 (23rd December 2019)
- Main Title:
- STEVE and the Picket Fence: Evidence of Feedback‐Unstable Magnetosphere‐Ionosphere Interaction
- Authors:
- Mishin, Evgeny
Streltsov, Anatoly - Abstract:
- Abstract: This paper aims to extend the understanding of Strong Thermal Emission Velocity Enhancement (STEVE) and the Picket Fence related to strong subauroral ion drifts (SAID). We numerically demonstrated that precipitating energetic electrons are critical for the structuring of the Picket Fence. It is created by feedback‐unstable magnetosphere‐ionosphere interactions driven by the SAID electric field when the Hall conductance created by energetic ( ≥ 1 keV) electrons exceeds the Pedersen conductance. We show that thermal excitation of the red‐line emission in STEVE is inhibited by inelastic collisions with molecular nitrogen. Suprathermal ( ≤ 500 eV) electrons coming from the turbulent plasmasphere appear to be the major source. We also show that the chemiluminescencent and radiative attachment reactions do not explain the short‐wavelength part of the STEVE continuum and argue that accounting for vibrational excitation may resolve the problem. Atmosphere's upwelling due to enhanced ion‐neutral drag leads to the increased abundance of molecular components relative to atomic oxygen. Key Points: Feedback‐unstable magnetosphere‐ionosphere interaction in the presence of energetic electron precipitation explains the Picket Fence formation Thermal excitation of the red‐line emission in the low‐density SAID channel is inhibited by inelastic collisions with molecular nitrogen To understand the STEVE continuum, transitions between vibrationally excited molecular states in the SAIDAbstract: This paper aims to extend the understanding of Strong Thermal Emission Velocity Enhancement (STEVE) and the Picket Fence related to strong subauroral ion drifts (SAID). We numerically demonstrated that precipitating energetic electrons are critical for the structuring of the Picket Fence. It is created by feedback‐unstable magnetosphere‐ionosphere interactions driven by the SAID electric field when the Hall conductance created by energetic ( ≥ 1 keV) electrons exceeds the Pedersen conductance. We show that thermal excitation of the red‐line emission in STEVE is inhibited by inelastic collisions with molecular nitrogen. Suprathermal ( ≤ 500 eV) electrons coming from the turbulent plasmasphere appear to be the major source. We also show that the chemiluminescencent and radiative attachment reactions do not explain the short‐wavelength part of the STEVE continuum and argue that accounting for vibrational excitation may resolve the problem. Atmosphere's upwelling due to enhanced ion‐neutral drag leads to the increased abundance of molecular components relative to atomic oxygen. Key Points: Feedback‐unstable magnetosphere‐ionosphere interaction in the presence of energetic electron precipitation explains the Picket Fence formation Thermal excitation of the red‐line emission in the low‐density SAID channel is inhibited by inelastic collisions with molecular nitrogen To understand the STEVE continuum, transitions between vibrationally excited molecular states in the SAID channel should be taken into account … (more)
- Is Part Of:
- Geophysical research letters. Volume 46:Issue 24(2019)
- Journal:
- Geophysical research letters
- Issue:
- Volume 46:Issue 24(2019)
- Issue Display:
- Volume 46, Issue 24 (2019)
- Year:
- 2019
- Volume:
- 46
- Issue:
- 24
- Issue Sort Value:
- 2019-0046-0024-0000
- Page Start:
- 14247
- Page End:
- 14255
- Publication Date:
- 2019-12-23
- Subjects:
- STEVE -- feedback‐unstable MI coupling -- effect of the Hall conductance -- suprathermal electron excitation
Geophysics -- Periodicals
Planets -- Periodicals
Lunar geology -- Periodicals
550 - Journal URLs:
- http://www.agu.org/journals/gl/ ↗
http://onlinelibrary.wiley.com/ ↗ - DOI:
- 10.1029/2019GL085446 ↗
- Languages:
- English
- ISSNs:
- 0094-8276
- Deposit Type:
- Legaldeposit
- View Content:
- Available online (eLD content is only available in our Reading Rooms) ↗
- Physical Locations:
- British Library DSC - 4156.900000
British Library DSC - BLDSS-3PM
British Library HMNTS - ELD Digital store - Ingest File:
- 20872.xml