Search Publications
First MMS Observation of Energetic Particles Trapped in High-Latitude Magnetic Field Depressions
Fuselier, Stephen A.; Nykyri, Katariina; Ma, Xuanye +2 more
We present a case study of the Magnetospheric Multiscale (MMS) observations of the Southern Hemispheric dayside magnetospheric boundaries under southward interplanetary magnetic field direction with strong By component. During this event MMS encountered several magnetic field depressions characterized by enhanced plasma beta and high fl…
Exospheric Neutral Hydrogen Density at the Nominal 10 RE Subsolar Point Deduced From XMM-Newton X-Ray Observations
Connor, Hyunju K.; Carter, Jennifer A.
We investigate the exospheric neutral density near the subsolar magnetopause, assuming Xgse = 10 RE as its typical location, to support the upcoming Solar wind-Magnetosphere-Ionosphere Link Explorer that will visualize the Earth's magnetosheath and cusps in soft X-rays. Neutral hydrogen density is a key parameter that controls soft X-ra…
The First Direct Observational Confirmation of Kinematic Collisionless Relaxation in Very Low Mach Number Shocks Near the Earth
Balikhin, M. A.; Gedalin, M.; Pope, S. A.
Collisionless shocks are ubiquitous throughout the known universe. They mainly convert the energy of the directed ion flow into heating. Upon crossing the shock front, the ion distribution becomes nongyrotropic. Relaxation to gyrotropy then occurs mainly via kinematic collisionless gyrophase mixing and interaction with waves. The theory of collisi…
Radio Occultation Observations of the Solar Corona Over 1.60-1.86 R⊙: Faraday Rotation and Frequency Shift Analysis
Lionello, Roberto; Hollweg, Joseph V.; Jensen, Elizabeth A. +5 more
The study of coronal energy transport, central to the solar wind acceleration problem, relies upon accurate representation of magnetic fields and plasma electron densities. This information is difficult to obtain in middle-to-lower coronal regions that may contain complex magnetic structures. Faraday rotation (FR) solar radio occultation observati…
Variability of Intra-D Ring Azimuthal Magnetic Field Profiles Observed on Cassini's Proximal Periapsis Passes
Dougherty, M. K.; Cowley, S. W. H.; Bunce, E. J. +4 more
We overview the properties of the azimuthal magnetic fields observed during the periapsis passes of the final 23 orbits of the Cassini spacecraft, including the partial orbit at end of mission, on near equatorial field lines passing inside of Saturn's D ring. The signatures are variable in form and amplitude, though generally approximately symmetr…
Signatures of Cold Ions in a Kinetic Simulation of the Reconnecting Magnetopause
Lavraud, B.; Toledo-Redondo, S.; Aunai, N. +2 more
At the Earth's magnetopause, a low-energy ion population of ionospheric origin is commonly observed at the magnetospheric side. In this work we use a 2-D fully kinetic simulation to identify several original signatures related to the dynamics of cold ions involved in magnetic reconnection at the asymmetric dayside magnetopause. We identify several…
Beyond the Minisolar Maximum of Solar Cycle 24: Declining Solar Magnetic Fields and the Response of the Terrestrial Magnetosphere
Janardhan, P.; Ingale, M.; Bisoi, S. K.
The present study examines the response of the terrestrial magnetosphere to the long-term steady declining trends observed in solar magnetic fields and solar wind microturbulence levels since mid-1990s that has been continuing beyond the minisolar maximum of cycle 24. A detailed analysis of the response of the terrestrial magnetosphere has been ca…
Recent Advancements and Remaining Challenges Associated With Inner Magnetosphere Cross-Energy/Population Interactions (IMCEPI)
Jordanova, Vania K.; Yu, Yiqun; Liemohn, Mike W. +2 more
The geospace inner magnetosphere, within about 10 Earth radii, contains various plasma populations with energy from a few electron volts to megaelectron volts and plays important roles in regulating the energy density of the magnetosphere, the magnetic field configuration, and wave dynamics. As an integrated part of the magnetosphere, the inner ma…
Proton Temperature Anisotropies in the Plasma Environment of Venus
Futaana, Y.; Zhang, T. L.; Nilsson, H. +5 more
Velocity distribution functions (VDFs) are a key to understanding the interplay between particles and waves in a plasma. Any deviation from an isotropic Maxwellian distribution may be unstable and result in wave generation. Using data from the ion mass spectrometer IMA (Ion Mass Analyzer) and the magnetometer (MAG) onboard Venus Express, we study …
Cassini Radio Occultation Observations of Titan's Ionosphere: The Complete Set of Electron Density Profiles
Dalba, Paul A.; Withers, Paul
Titan's ionosphere is an important component of the moon's environment. Ionospheric densities above ≈900 km have been studied with in situ measurements, but few density profiles for lower altitudes has been reported. Here we report the generation of the complete set of twenty ionospheric electron density profiles from the Cassini Radio Science Sub…