<<View 2018 THEMIS Nuggets

Ligia Alves, February 2019
Contribution of ULF wave activity to the global recovery of the outer radiation belt during the passage of a high-speed solar wind stream observed in September 2014

We use ground-based and satellite data with numerical simulations to describe how Ultra-Low Frequency (ULF) wave activities contributed to the global recovery of the relativistic electron population in the outer radiation belt, during the passage of Alfvénic solar wind streams. Read more.

Stein Haaland, April 2019
THEMIS reveals a puzzling asymmetry in near-Earth space

THEMIS reveals a puzzling asymmetry in space at the magnetopause, the boundary between the solar wind and Earth's magnetic field. Read more.

Lydia Bingley, June 2019
The Evolution of a Pitch-Angle "Bite-Out" Scattering Signature Caused by EMIC Wave Activity: A Case Study

EMIC waves have long been considered a candidate for influencing the loss or energetic electrons from the radiation belts. This study presents the first direct observation of a "bite-out" scattering signature co-located with the responsible wave activity, proving that EMIC waves can have a direct and verifiable impact on radiation belt electrons. Read more.

Justin Lee, October 2019
MMS Measurements and Modeling of Peculiar Ion Cyclotron Waves

A measurement technique originally developed to measure low-energy ions during bulk plasma flows in Earth’s magnetosphere with THEMIS was applied to measurements made by the MMS satellites, enabling characterization of ion composition in unprecedented detail during an interval of peculiar EMIC wave activity. The complex MMS datasets were then applied to more accurately investigate the relationship between plasma composition and EMIC waves, showing the wave activity was not peculiar but instead consistent with theory. Read more.

Daiki Koga, October 2019
Dayside Magnetopause Reconnection: Its Dependence on Solar Wind and Magnetosheath Conditions

It has not been fully understood under which interplanetary/magnetosheath conditions magnetic reconnection takes place more effectively at the dayside magnetopause. In the present study 25 dayside magnetopause reconnection events are investigated using THEMIS satellite observations in order to find their dependence on solar wind and magnetosheath conditions. Read more.

Kento Fukui, November 2019
A statistical study of near-Earth magnetotail evolution during pseudosubstorms and substorms with THEMIS data

We statistically compared near-Earth magnetotail changes associated with pseudosubstorm and substorm onsets. We suggest that near-Earth magnetotail conditions are important for determining a full-fledged substorm or a subsiding pseudosubstorm. Read more.

Olga Gutynska, December 2019
Sheath-like solar wind deflection upstream of the bow shock

We present evidence of sheath-like solar wind deflection upstream of the bow shock observed by THEMIS spacecraft. New results from a 2.5-D electromagnetic hybrid simulation in the foreshock under radial IMF confirm spacecraft observations. Read more.

Please send comments/suggestions to
Emmanuel Masongsong / emasongsong @ igpp.ucla.edu