A5087635091- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Astro and Planetary Science
- Geomagnetism and Paleomagnetism Studies
- Planetary Science and Exploration
- Earthquake Detection and Analysis
- Space Exploration and Technology
- Magnetic confinement fusion research
- Laser-induced spectroscopy and plasma
- Dust and Plasma Wave Phenomena
- Plasma Diagnostics and Applications
- Gamma-ray bursts and supernovae
- GNSS positioning and interference
- Astrophysics and Cosmic Phenomena
- Geophysics and Gravity Measurements
- Isotope Analysis in Ecology
- Atomic and Subatomic Physics Research
- Geology and Paleoclimatology Research
- Atomic and Molecular Physics
- Space Satellite Systems and Control
- High-pressure geophysics and materials
- Stellar, planetary, and galactic studies
- Atmospheric Ozone and Climate
- Astrophysics and Star Formation Studies
- Theoretical and Computational Physics
Planetary Science Institute
2015-2025
Adolfo Ibáñez University
2023
Brigham Young University
2023
Jet Propulsion Laboratory
2005-2021
Massachusetts Institute of Technology
2021
Los Alamos National Laboratory
2011-2020
NOAA National Weather Service
2013
Technische Universität Braunschweig
2011
Los Alamos National Security (United States)
1998-2011
Southwest Research Institute
1997-2009
The Radiation Belt Storm Probes (RBSP)-Energetic Particle, Composition, and Thermal Plasma (ECT) suite contains an innovative complement of particle instruments to ensure the highest quality measurements ever made in inner magnetosphere radiation belts. coordinated RBSP-ECT measurements, analyzed combination with fields waves observations state-of-the-art theory modeling, are necessary for understanding acceleration, global distribution, variability belt electrons ions, key science...
The HOPE mass spectrometer of the Radiation Belt Storm Probes (RBSP) mission (renamed Van Allen Probes) is designed to measure in situ plasma ion and electron fluxes over 4π sr at each RBSP spacecraft within terrestrial radiation belts. scientific goal understand underlying physical processes that govern belt structure dynamics. Spectral measurements for both ions electrons are acquired 1 eV 50 keV 36 log-spaced steps an energy resolution ΔE FWHM/E≈15 %. dominant species (H+, He+, O+)...
A survey of two‐dimensional electron velocity distributions, ƒ( V ), measured near the earth's bow shock using Los Alamos/Garching plasma instrumentation aboard ISEE 2 is presented. This provides clues to mechanisms thermalization within and relaxation both upstream downstream distributions. First, foreshock boundary, fluxes electrons having a power law shape at high energies backstream from shock. Although most often they appear as monotonically decreasing extension solar wind distributions...
The coupling of the plasma sheet to solar wind is studied statistically using measurements from various satellite pairs: one in and either magnetotail central or near‐Earth sheet. It found that properties are highly correlated with wind: specifically (1) density strongly wind, (2) temperature velocity (3) particle pressure total ram (4) B y (5) z weakly (6) E (7) earthward‐tailward flow anticorrelated velocity. After removing these dependencies, dependencies on geomagnetic activity reduced...
Three storms are examined to determine the contribution Dst * index from symmetric and asymmetric (partial) components of ring current. The (September 24–25, 1998, October 18–19, May 14–15, 1997) all have a similar solar wind trigger (an initial shock followed by coronal mass ejection with southward interplanetary magnetic field) placement in cycle (rising phase). near‐Earth ion distribution function is simulated for each storm using kinetic transport model. use McIlwain magnetospheric...
During Cassini's initial orbit, we observed a dynamic magnetosphere composed primarily of complex mixture water-derived atomic and molecular ions. We have identified four distinct regions characterized by differences in both bulk plasma properties ion composition. Protons are the dominant species outside about 9 RS (where is radial distance from center Saturn), whereas inside, consists corotating comet-like mix ions with approximately 3% N+. Over A B rings, found an ionosphere which O2+ O+...
We study mechanisms contributing to proton precipitation from the ring current during May 14–16, 1997, geomagnetic storm. This storm was caused partly by B z < 0 fields in sheath region behind an interplanetary shock and magnetic cloud driving shock. The characterized a maximum Kp =7 − minimum Dst =−115 nT had distinctive two‐phase decay related passage of ejection at Earth. model development adiabatic drifts losses due charge exchange, Coulomb collisions, wave‐particle interactions,...
Measurements made with the Fast Plasma Experiment on ISEE 2 in vicinity of high‐latitude, dusk magnetopause near terminator plane, at a time when local magnetosheath and tail lobe magnetic fields were nearly oppositely directed, provide direct evidence for reconnection open field lines lobes interplanetary (IMF). The consists primarily observations accelerated plasma flowing both tailward sunward within high‐latitude current layer. Observed speed changes order twice Alfven quantitatively...
The bulk flows and magnetic-field fluctuations of the plasma sheet are investigated using single-point measurements from ISEE-2 Fast Plasma Experiment fluxgate magnetometer. Ten several-hour-long intervals continuous data (with 3 s 12 time resolution) analysed. plasma-sheet flow appears to be strongly ‘turbulent’ (i.e. is dominated by that unpredictable, with rms velocities[Gt ]mean velocities field fluctuations≈mean fields). typically sub-Alfvénic. flow-velocity probability distribution P (...
A number of events have been observed in the Los Alamos/Garching fast plasma experiment data from ISEE 2 within ±3 hours noon wherein y component flow low latitude boundary layer and magnetopause current is oppositely directed to that adjacent magnetosheath. When component, B , local magnetosheath magnetic field positive, this nature are found preferentially northern dusk southern dawn quadrants, when negative, they opposite two quadrants. Plasma flows these always also poleward, away GSE...
A survey of the bulk plasma ion properties observed by Cassini Plasma Spectrometer instrument over roughly first 4.5 years its mission in orbit around Saturn is presented. The moments (density, temperature, and flow velocity) distributions below 50 keV have been computed numerical integration counts “Singles” (non‐mass‐resolved) data, partitioned into species on basis concurrent determinations composition from time‐of‐flight data. Moments are presented for three main species: H + , W (water...
A light-weight, low-power, plasma analyzer is described that can be used for measuring the environments of spacecraft with constrained resources. unique system using a single electrostatic coupled to array channel electron multipliers allows measurement three-dimensional energy per charge distributions both ions and electrons over E/q ranges from ∼1 eV/q ≳40 keV/q. Particles selected by are post-accelerated into maintain sensitivity lowest particles. An instrument this concept called...
The interaction of the solar wind and Earth's magnetosphere is complex phenomenology very different for dominated by interplanetary coronal mass ejections (ICMEs) compared to corotating regions (CIRs). We perform a superposed epoch study effects ICME‐ CIR‐dominated upon storm‐time plasma at geosynchronous orbit using data from magnetospheric analyzer (MPA) instruments on board seven Los Alamos National Laboratory (LANL) satellites. Using 78 ICME events 32 CIR events, we examine electron ion...
The substorm‐associated behavior of the thermal plasma (30eV < E 40keV) in sheet is examined by means a superposed epoch analysis, using full year data from spacecraft geosynchronous orbit. zero time taken to be substorm onset as indicated dispersionless energetic particle injection observed on same spacecraft. Five classes events are found well ordered their average local times. These range pure ion injections ∼3 hours prior midnight, followed few minutes later an electron ∼2 before...
The electron heating and the electrostatic potential jump across collisionless shocks play an important, if not dominant, role in momentum balance. We present here a survey of these two quantities over large sample fast mode shocks. Results for estimates (as measured de Hoffmann‐Teller reference frame) based on estimate enthalpy Liouville's theorem correlate well with each other, although latter are consistently higher, perhaps due to irreversible processes affecting shock dynamics. size...
Magnetosheath plasma entering the Earth's magnetosphere to populate low latitude boundary layer, LLBL, is often accelerated speeds considerably greater than are observed in adjacent magnetosheath. Measurements made during such flow events separate electron and ion edges with edge being found earthward of edge, velocity distributions at LLBL highly structured, exhibiting large asymmetries parallel antiparallel, as perpendicular, local magnetic field. These can consistently be interpreted...
Ion velocity distributions in the form of bunches gyrating particles traveling along helical paths have been observed moving sunward immediately upstream from quasi‐parallel parts earth's bow shock using Los Alamos/Garching instruments on ISEE‐1 and ‐2. These characteristics which indicate that they are produced by nearly specular reflection at a portion incident solar wind ions. In particular, guiding center motion gyrospeeds ions quantitatively consistent with simple geometrical...
One year's worth of magnetospheric plasma analyzer data from three Los Alamos geosynchronous satellites are used for a statistical study proton and electron fluxes at orbit their dependence on local time (LT) geomagnetic activity level as measured by Kp . When displayed function LT , the exhibit distinct boundaries, which shown to be consistent with combination global pattern particle drift through magnetosphere loss processes mainly due charge exchange ions auroral precipitation electrons....
The first three magnetospheric plasma analyzer (MPA) instruments have been returning data from geosynchronous orbit nearly continuously since late 1989, 1990, and 1991. These identical provide for the time simultaneous observations widely spaced locations. MPA measure three‐dimensional velocity space distributions of both electrons ions with energies between ∼1 eV/q ∼40 keV/q. capabilities are summarized in this paper. We use longitudinally separated spacecraft to synthesize a synoptic view...
A strong interaction between the solar wind and comet Giacobini-Zinner was observed oh 11 September 1985 with Los Alamos plasma electron experiment on International Cometary Explorer (ICE) spacecraft. As ICE approached an intercept point 7800 kilometers behind nucleus from south receded to north, upstream phenomena due were observed. Periods of enhanced heat flux as well almost continuous density fluctuations measured. These effects are related heating in cometary region ion pickup by wind,...
We investigate electron acceleration and the flux increases associated with energetic injections on basis of geosynchronous observations test‐electron orbits in dynamic fields a three‐dimensional MHD simulation neutral line formation dipolarization magnetotail. This complements an earlier investigation test protons [ Birn et al ., 1997b]. In present paper we consider equatorial only, using gyrocenter drift approximation. It turns out that this approximation is valid for electrons prior to...
During the 14 July 2005 encounter of Cassini with Enceladus, Plasma Spectrometer measured strong deflections in corotating ion flow, commencing at least 27 Enceladus radii (27 x 252.1 kilometers) from Enceladus. The Radio and Wave Science instrument inferred little plasma density increase near These data are consistent formation via charge exchange pickup by Saturn's magnetic field. occurs between neutrals atmosphere ions inner magnetosphere. Pickup observed a total mass loading rate about...
A theoretical framework is developed for studying trajectories of ions reflected or leaked upstream from the earth's bow shock and subject solely to Lorentz force in a steady interplanetary magnetic field B V×B electric field. We include effects sharp potential rise. Expressions are derived guiding center motion gyromotion frame (the Hoffman‐Teller frame) moving parallel surface with sufficient speed transform incident solar wind velocity into entirely along field; appropriate equations also...