Search Publications
Statistical Study of Electric Pc5 Pulsations in the Inner Magnetosphere Observed by Cluster
Li, Xinlin; Liu, Wenlong; Zhang, Dianjun +3 more
Ultra-low frequency (ULF) waves in the Pc5 band are essential for the transport of electrons in the radiation belt and the transport of energy from the solar wind into the magnetosphere. Based on ∼14-year of electric field data from Cluster satellite, the spatial distributions of power spectral densities (PSD) of electric field ULF waves in the in…
Frequency Chirping of Electromagnetic Ion Cyclotron Waves in Earth's Magnetosphere
An, Zeyu; Tao, Xin; Zonca, Fulvio +1 more
Electromagnetic ion cyclotron (EMIC) waves are known to exhibit frequency chirping occasionally, contributing to the rapid acceleration and precipitation of energetic particles in the magnetosphere. However, the chirping mechanism of EMIC waves remains elusive. In this work, a phenomenological model of whistler mode chorus waves named the Trap-Rel…
Latitudinal Mapping of Chorus Waves Growth Rates Based on Multi-Spacecraft Wave and Plasma Measurements
Agapitov, O. V.; Artemyev, A.; Mourenas, D. +3 more
Whistler mode chorus waves are one of the most intense and important electromagnetic emissions in the Earth's radiation belt, where these waves are responsible for electron acceleration to relativistic energies and for energetic electron precipitation into the Earth's atmosphere. This study reports a unique multi-spacecraft observation event that …
In Situ Observational Evidence of the Polar Cap Arc at 1500 MLT (15MLT-PCA) Associated With the Lobe Reconnection
Shi, Run; Han, Desheng; Feng, Huiting +4 more
The polar cap arc at 1500 MLT (15MLT-PCA) has been considered as an auroral signature of the cusp's duskside boundary and been speculated to be caused by lobe reconnection. However, no observational evidence has been provided to support this speculation. Here we report a 15MLT-PCA event occurred on 29 November 2017 using multi-instrument observati…
Simultaneous Global Ionospheric Disturbances Associated With Penetration Electric Fields During Intense and Minor Solar and Geomagnetic Disturbances
Nishimura, Yukitoshi; Zhang, Shun-Rong; Vierinen, Juha +8 more
A new observational phenomenon, named Simultaneous Global Ionospheric Density Disturbance (SGD), is identified in GNSS total electron content (TEC) data during periods of three typical geospace disturbances: a Coronal Mass Ejection-driven severe disturbance event, a high-speed stream event, and a minor disturbance day with a maximum Kp of 4. SGDs …
Electron Heating Scales in Collisionless Shocks Measured by MMS
Johlander, Andreas; Khotyaintsev, Yuri V.; Dimmock, Andrew P. +2 more
Electron heating at collisionless shocks in space is a combination of adiabatic heating due to large-scale electric and magnetic fields and non-adiabatic scattering by high-frequency fluctuations. The scales at which heating happens hints to what physical processes are taking place. In this letter, we study electron heating scales with data from t…
PIC Simulations of Overstretched Ion-Scale Current Sheets in the Magnetotail
Arnold, H.; Sitnov, M. I.
Onset of reconnection in the tail requires the current sheet thickness to be of the order of the ion thermal gyroradius or smaller. However, existing isotropic plasma models cannot explain the formation of such thin sheets at distances where the X-lines are typically observed. Here we reproduce such thin and long sheets in particle-in-cell simulat…
Electron Rolling-Pin Distributions Preceding Dipolarization Fronts
Cao, J. B.; Liu, C. M.; Xing, X. N.
Electron rolling-pin distribution (RPDs), characterized by triple peaks at pitch angles 0°, 90°, and 180°, have recently been discovered in the terrestrial magnetosphere. Since the RPDs' formation is typically attributed to local betatron acceleration, RPDs have been believed to appear primarily inside strong magnetic regions, such as flux pileup …
Simultaneous Mesoscale Polar Cusp Field-Aligned Currents Measured on Mid- and Low-Altitude Satellites
Dunlop, M. W.; Dong, X. -C.; Xiao, C. +3 more
Using a conjunction of Cluster in the mid-altitude dayside magnetosphere and Swarm in the low-altitude ionosphere, we show, by employing multi-spacecraft analysis, that matched, strong magnetic perturbations and the corresponding mesoscale field-aligned current (FAC) structures are measured in the high latitude polar cusp region during the 7 Octob…
Multispacecraft Observations of the Simultaneous Occurrence of Magnetic Reconnection at High and Low Latitudes During the Passage of a Solar Wind Rotational Discontinuity Embedded in the April 9-11, 2015 ICME
Lugaz, Noé; Escoubet, C. Philippe; Wing, Simon +2 more
Numerous questions remain about how solar wind directional discontinuities, for example, rotational discontinuities (RDs), affect energy and transport processes at the magnetopause. The impact on the dayside magnetosphere of a solar wind RD is studied. The study shows that the RD leads to complex structures at the magnetopause, boundary layer, man…