Found 673 results
Filters: Keyword is Van Allen Probes  [Clear All Filters]
Authors: Jordanova V K, Yu Y., Niehof J T, Skoug R M, Reeves G D, et al.
Title: Simulations of inner magnetosphere dynamics with an expanded RAM-SCB model and comparisons with Van Allen Probes observations
Abstract: Simulations from our newly expanded ring current-atmosphere interactions model with self-consistent magnetic field (RAM-SCB), now valid out to 9 RE, are compared for the first time with Van Allen Probes observations. The expanded model reproduces the storm time ring current buildup due to the increased convection and inflow of plasma from the magnetotail. It matches Magnetic Electron Ion Spectrometer (MagEIS) observations of the trapped high-energy (>50 keV) ion flux; however, it underestimates the low-energy (<10 keV) Helium, Oxygen, Proton, and Electron (HOPE) observations. The dispersed injections of ring current ions observed with the Energetic particle, Composition, and Thermal plasma (ECT) suite at high (>20 keV) energy are better reproduced using a high-resolution convection model. . . .
Date: 04/2014 Publisher: Geophysical Research Letters Pages: 2687 - 2694 DOI: 10.1002/2014GL059533 Available at:
More Details
Authors: Reid Mark, and Ottman Geffrey
Title: Software controlled memory scrubbing for the Van Allen Probes Solid State Recorder (SSR) memory
Abstract: The Van Allen Probes mission which was designed and built by the Johns Hopkins University, Applied Physics Laboratory (APL) is also being operated by the APL mission operations team in Laurel, Maryland. The two Van Allen Probes spacecraft have been successfully collecting data on orbit since they were launched on August 30, 2012. These twin probes are providing unprecedented insight into the physical dynamics of the Earth's radiation belts and are giving scientists the data they need to make predictions of changes in this critical region of space, by sampling the harsh radiation belt environment where major space weather activity occurs and many spacecraft operate.[1] Shortly after launch, radiation induced anomalies were reported on both spacecraft and investigated by the hardware and sof. . .
Date: 03/2014 Publisher: IEEE DOI: 10.1109/AERO.2014.6836406 Available at:
More Details
Authors: Turner Drew L
Title: Space science: Near-Earth space shows its stripes
Abstract: Using some of the first scientific satellites put into orbit during the late 1950s, teams led by physicists James Van Allen in the United States and Sergei Vernov in the Soviet Union independently reported1, 2 on defined regions of radiation in near-Earth space. These regions came to be known as Earth's radiation belts, and they represent the first major scientific discovery of the space age. However, despite decades of study, many questions in radiation-belt physics remain unanswered, mostly concerning the nature of the inner and outer belts, which are populated by electrons moving at near the speed of light. As society becomes ever more dependent on satellite-based technology, it is increasingly important to understand the variability in the radiation belts, because the highest-energy . . .
Date: 03/2014 Publisher: Nature Pages: 308 - 309 DOI: 10.1038/507308a Available at:
More Details
Authors: Mann I. R., Usanova M. E., Murphy K., Robertson M. T., Milling D. K., et al.
Title: Spatial localization and ducting of EMIC waves: Van Allen Probes and ground-based observations
Abstract: On 11 October 2012, during the recovery phase of a moderate geomagnetic storm, an extended interval (> 18 h) of continuous electromagnetic ion cyclotron (EMIC) waves was observed by Canadian Array for Real-time Investigations of Magnetic Activity and Solar-Terrestrial Environment Program induction coil magnetometers in North America. At around 14:15 UT, both Van Allen Probes B and A (65° magnetic longitude apart) in conjunction with the ground array observed very narrow (ΔL ~ 0.1–0.4) left-hand polarized EMIC emission confined to regions of mass density gradients at the outer edge of the plasmasphere at L ~ 4. EMIC waves were seen with complex polarization patterns on the ground, in good agreement with model results from Woodroffe and Lysak (2012) and consistent with Earth's . . .
Date: 02/2014 Publisher: Geophysical Research Letters Pages: 785 - 792 DOI: 10.1002/2013GL058581 Available at:
More Details
Authors: Berman Simmie, Cheng Weilun, Borowski Heather, and Persons David
Title: Spin stabilization design and testing of the Van Allen Probes
Abstract: This paper describes the design decisions taken and the mass properties tracking and testing flow chosen for the Van Allen Probes spacecraft and their deployable systems to achieve the coning angle requirements. Topics include a list of major requirements, a brief description of the error budget, a description of the tracking process of the spacecraft mass properties prior to test, a description of the spin balance and mass properties testing of the spacecraft core and deployable systems, and a presentation of the final mass properties and coning angle calculations of the fully deployed observatories. Launched August 30, 2012, the observed on-orbit, fully deployed configuration coning angles met the requirements, validating the spin balance and mass properties tracking, testing, and calcul. . .
Date: 03/2014 Publisher: IEEE DOI: 10.1109/AERO.2014.6836234 Available at:
More Details
Authors: Santolik O, Hospodarsky G B, Kurth W S, Averkamp T. F., Kletzing C A, et al.
Title: Statistical properties of wave vector directions of whistler-mode waves in the radiation belts based on measurements of the Van Allen probes and Cluster missions
Abstract: Wave-particle interactions in the Earth's Van Allen radiation belts are known to be an efficient process of the exchange of energy between different particle populations, including the energetic radiation belt particles. The whistler mode waves, especially chorus, can control the radiation belt dynamics via linear or nonlinear interactions with both the energetic radiation belt electrons and lower energy electron populations. Wave vector directions are a very important parameter of these wave-particle interactions. We use measurements of whistlermode waves by the WAVES instrument from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) onboard the Van Allen Probes spacecraft covering the equatorial region of the Earth's magnetosphere in all MLT sectors, and a . . .
Date: 08/2014 Publisher: IEEE DOI: 10.1109/URSIGASS.2014.6929880 Available at:
More Details
Authors: Foster J. C., Erickson P. J., Coster A. J., Thaller S., Tao J., et al.
Title: Storm time observations of plasmasphere erosion flux in the magnetosphere and ionosphere
Abstract: Plasmasphere erosion carries cold dense plasma of ionospheric origin in a storm-enhanced density plume extending from dusk toward and through the noontime cusp and dayside magnetopause and back across polar latitudes in a polar tongue of ionization. We examine dusk sector (20 MLT) plasmasphere erosion during the 17 March 2013 storm (Dst ~ −130 nT) using simultaneous, magnetically aligned direct sunward ion flux observations at high altitude by Van Allen Probes RBSP-A (at ~3.0 Re) and at ionospheric heights (~840 km) by DMSP F-18. Plasma erosion occurs at both high and low altitudes where the subauroral polarization stream flow overlaps the outer plasmasphere. At ~20 UT, RBSP-A observed ~1.2E12 m−2 s−1 erosion flux, while DMSP F-18 observed ~2E13 m−2 s−1 sunward flux. We. . .
Date: 02/2014 Publisher: Geophysical Research Letters Pages: 762 - 768 DOI: 10.1002/2013GL059124 Available at:
More Details
Authors: Makela Jonathan J., Harding Brian J., Meriwether John W., Mesquita Rafael, Sanders Samuel, et al.
Title: Storm time response of the mid-latitude thermosphere: Observations from a network of Fabry-Perot interferometers
Abstract: Observations of thermospheric neutral winds and temperatures obtained during a geomagnetic storm on 2 October 2013 from a network of six Fabry-Perot interferometers (FPIs) deployed in the midwest United States are presented. Coincident with the commencement of the storm, the apparent horizontal wind is observed to surge westward and southward (towards the equator). Simultaneous to this surge in the apparent horizontal winds, an apparent downward wind of approximately 100 m/s lasting for 6 hours is observed. The apparent neutral temperature is observed to increase by approximately 400 K over all of the sites. Observations from an all-sky imaging system operated at the Millstone Hill observatory indicate the presence of a stable auroral red (SAR) arc and diffuse red aurora during this . . .
Date: 08/2014 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA019832 Available at:
More Details
Authors: Artemyev A. V., Agapitov O. V., Mozer F, and Krasnoselskikh V.
Title: Thermal electron acceleration by localized bursts of electric field in the radiation belts
Abstract: In this paper we investigate the resonant interaction of thermal ~10−100 eV electrons with a burst of electrostatic field that results in electron acceleration to kilovolt energies. This single burst contains a large parallel electric field of one sign and a much smaller, longer lasting parallel field of the opposite sign. The Van Allen Probe spacecraft often observes clusters of spatially localized bursts in the Earth's outer radiation belts. These structures propagate mostly away from thegeomagnetic equator and share properties of soliton-like nonlinear electron-acoustic waves: a velocity of propagation is about the thermal velocity of cold electrons (~3000−10000 km/s), and a spatial scale of electric field localization alongthe field lines is about the Debye radius of hot electrons . . .
Date: 08/2014 Publisher: Geophysical Research Letters DOI: 10.1002/2014GL061248 Available at:
More Details
Authors: Ma Q, Li W, Chen L, Thorne R M, Kletzing C A, et al.
Title: The trapping of equatorial magnetosonic waves in the Earth's outer plasmasphere
Abstract: We investigate the excitation and propagation of equatorial magnetosonic waves observed by the Van Allen Probes and describe evidence for a trapping mechanism for magnetosonic waves in the Earth's plasmasphere. Intense equatorial magnetosonic waves were observed inside the plasmasphere in association with a pronounced proton ring distribution, which provides free energy for wave excitation. Instability analysis along the inbound orbit demonstrates that broadband magnetosonic waves can be excited over a localized spatial region near the plasmapause. The waves can subsequently propagate into the inner plasmasphere and remain trapped over a limited radial extent, consistent with the predictions of near-perpendicular propagation. By performing a similar analysis on another observed magnetosoni. . .
Date: 09/2014 Publisher: Geophysical Research Letters Pages: 6307 - 6313 DOI: 10.1002/2014GL061414 Available at:
More Details
Authors: Betz Eric O.
Title: Trapping waves in Earth's plasmasphere
Abstract: Earth's magnetic field traps donut-shaped bands of radiation in a belt around the planet that react to solar eruptions by growing and shrinking. The Van Allen belts consist of two rings filled with particles from the solar wind and cosmic rays. Within the outer ring of the Van Allen belt sits the plasmasphere, which is the innermost part of the planet's magnetic field and home to low-energy charged particles.
Date: 12/2014 Publisher: Eos, Transactions American Geophysical Union Pages: 472 - 472 DOI: 10.1002/2014EO490016 Available at:
More Details
Authors: Boardsen S. A., Hospodarsky G B, Kletzing C A, Pfaff R. F., Kurth W S, et al.
Title: Van Allen Probe Observations of Periodic Rising Frequencies of the Fast Magnetosonic Mode
Abstract: Near simultaneous periodic dispersive features of fast magnetosonic mode emissions are observed by both Van Allen Probes spacecraft while separated in magnetic local time by ~5 hours: Probe A at 15 and Probe B at 9–11 hours. Both spacecraft see similar frequency features, characterized by a periodic repetition at ~180 s. Each repetition is characterized by a rising frequency. Since no modulation is observed in the proton shell distribution, the plasma density, or in the background magnetic field at either spacecraft we conclude that these waves are not generated near the spacecraft but external to both spacecraft locations. Probe A while outside the plasmapause sees the start of each repetition ~40 s before probe B while deep inside the plasmasphere. We can qualitatively reproduce . . .
Date: 12/2014 Publisher: Geophysical Research Letters DOI: 10.1002/2014GL062020 Available at:
More Details
Authors: Fennell J. F., Roeder J. L., Kurth W S, Henderson M G, Larsen B A, et al.
Title: Van Allen Probes observations of direct wave-particle interactions
Abstract: Quasiperiodic increases, or “bursts,” of 17–26 keV electron fluxes in conjunction with chorus wave bursts were observed following a plasma injection on 13 January 2013. The pitch angle distributions changed during the burst events, evolving from sinN(α) to distributions that formed maxima at α = 75–80°, while fluxes at 90° and <60° remained nearly unchanged. The observations occurred outside of the plasmasphere in the postmidnight region and were observed by both Van Allen Probes. Density, cyclotron frequency, and pitch angle of the peak flux were used to estimate resonant electron energy. The result of ~15–35 keV is consistent with the energies of the electrons showing the flux enhancements and corresponds to electrons in and above the steep flux gradient that signa. . .
Date: 03/2014 Publisher: Geophysical Research Letters Pages: 1869 - 1875 DOI: 10.1002/2013GL059165 Available at:
More Details
Authors: Fu Xiangrong, Cowee Misa M., Friedel Reinhard H., Funsten Herbert O, Gary Peter, et al.
Title: Whistler Anisotropy Instabilities as the Source of Banded Chorus: Van Allen Probes Observations and Particle-in-Cell Simulations
Abstract: Magnetospheric banded chorus is enhanced whistler waves with frequencies ωr < Ωe, where Ωe is the electron cyclotron frequency, and a characteristic spectral gap at ωr ≃ Ωe/2. This paper uses spacecraft observations and two-dimensional particle-in-cell (PIC) simulations in a magnetized, homogeneous, collisionless plasma to test the hypothesis that banded chorus is due to local linear growth of two branches of the whistler anisotropy instability excited by two distinct, anisotropic electron components of significantly different temperatures. The electron densities and temperatures are derived from HOPE instrument measurements on the Van Allen Probes A satellite during a banded chorus event on 1 November 2012. The observations are consistent with a three-component electron mod. . .
Date: 10/2014 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020364 Available at:
More Details
Authors: Ginet G P, ’Brien T P, Huston S L, Johnston W R, Guild T B, et al.
Title: AE9, AP9 and SPM: New Models for Specifying the Trapped Energetic Particle and Space Plasma Environment
Abstract: The radiation belts and plasma in the Earth’s magnetosphere pose hazards to satellite systems which restrict design and orbit options with a resultant impact on mission performance and cost. For decades the standard space environment specification used for spacecraft design has been provided by the NASA AE8 and AP8 trapped radiation belt models. There are well-known limitations on their performance, however, and the need for a new trapped radiation and plasma model has been recognized by the engineering community for some time. To address this challenge a new set of models, denoted AE9/AP9/SPM, for energetic electrons, energetic protons and space plasma has been developed. The new models offer significant improvements including more detailed spatial resolution and the quantification of u. . .
Date: 11/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-013-9964-y Available at:
More Details
Authors: Mauk B H
Title: Analysis of EMIC-wave-moderated flux limitation of measured energetic ion spectra in multispecies magnetospheric plasmas
Abstract: A differential Kennel-Petschek (KP) flux limit for magnetospheric energetic ions is devised taking into account multiple ion species effects on electromagnetic ion cyclotron (EMIC) waves that scatter the ions. The idea is that EMIC waves may limit the highest ion intensities during acceleration phases of storms and substorms (~ hour) while other mechanisms (e.g., charge exchange) may account for losses below those limits and over longer periods of time. This approach is applied to published Earth magnetosphere energetic ion spectra (~ keV to ~1 MeV) for radial positions (L) 3 to 6.7 RE. The flatness of the most intense spectral shapes for <100 keV indicate sculpting by just such a mechanism, but modifications of traditional KP parameters are needed to account for maximum fluxes up to 5. . .
Date: 08/2013 Publisher: Geophysical Research Letters Pages: 3804 - 3808 DOI: 10.1002/grl.50789 Available at:
More Details
Authors: Millan R M, McCarthy M P, Sample J G, Smith D M, Thompson L D, et al.
Title: The Balloon Array for RBSP Relativistic Electron Losses (BARREL)
Abstract: BARREL is a multiple-balloon investigation designed to study electron losses from Earth’s Radiation Belts. Selected as a NASA Living with a Star Mission of Opportunity, BARREL augments the Radiation Belt Storm Probes mission by providing measurements of relativistic electron precipitation with a pair of Antarctic balloon campaigns that will be conducted during the Austral summers (January-February) of 2013 and 2014. During each campaign, a total of 20 small (∼20 kg) stratospheric balloons will be successively launched to maintain an array of ∼5 payloads spread across ∼6 hours of magnetic local time in the region that magnetically maps to the radiation belts. Each balloon carries an X-ray spectrometer to measure the bremsstrahlung X-rays produced by precipitating relativistic electr. . .
Date: 11/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-013-9971-z Available at:
More Details
Authors: Lee Jeongwoo, Min Kyungguk, and Kim Kap-Sung
Title: Characteristic dimension of electromagnetic ion cyclotron wave activity in the magnetosphere
Abstract: [1] In this paper, we estimate the size of coherent activity of electromagnetic ion cyclotron (EMIC) waves using the multi‒spacecraft observations made during the Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission. We calculate the cross‒correlations between EMIC wave powers measured by different THEMIS spacecraft, plot them over the separation distances between pairs of observing spacecraft, and determine the 1/e folding distance of the correlations as the characteristic dimension of the coherent wave activity. The characteristic radius in the direction transverse to the local magnetic field is found to lie in rather a wide range of 1500–8600 km varying from the AM to PM sectors and also from hydrogen to helium bands. However, the characteristic d. . .
Date: 04/2013 Publisher: Journal of Geophysical Research: Space Physics Pages: 1651 - 1658 DOI: 10.1002/jgra.50242 Available at:
More Details
Authors: Li W, Ni B, Thorne R M, Bortnik J, Green J C, et al.
Title: Constructing the global distribution of chorus wave intensity using measurements of electrons by the POES satellites and waves by the Van Allen Probes
Abstract: We adopt a physics-based technique to infer chorus wave amplitudes from the low-altitude electron population (30–100 keV) measured by multiple Polar Orbiting Environmental Satellites (POES), which provide extensive coverage over a broad region in L-shell and magnetic local time (MLT). This technique is validated by analyzing conjunction events between the Van Allen Probes measuring chorus wave amplitudes near the equator and POES satellites measuring the 30–100 keV electron population at the conjugate low altitudes. We apply this technique to construct the chorus wave distributions during the 8–9 October storm in 2012 and demonstrate that the inferred chorus wave amplitudes agree reasonably well with conjugate measurements of chorus wave amplitudes from the Van Allen Probes. The . . .
Date: 09/2013 Publisher: Geophysical Research Letters Pages: 4526 - 4532 DOI: 10.1002/grl.v40.1710.1002/grl.50920 Available at:
More Details
Authors: Mann Ian R., Lee E. A., Claudepierre S G, Fennell J. F., Degeling A., et al.
Title: Discovery of the action of a geophysical synchrotron in the Earth’s Van Allen radiation belts
Abstract: Although the Earth’s Van Allen radiation belts were discovered over 50 years ago, the dominant processes responsible for relativistic electron acceleration, transport and loss remain poorly understood. Here we show evidence for the action of coherent acceleration due to resonance with ultra-low frequency waves on a planetary scale. Data from the CRRES probe, and from the recently launched multi-satellite NASA Van Allen Probes mission, with supporting modeling, collectively show coherent ultra-low frequency interactions which high energy resolution data reveals are far more common than either previously thought or observed. The observed modulations and energy-dependent spatial structure indicate a mode of action analogous to a geophysical synchrotron; this new mode of response represents . . .
Date: 11/2013 Publisher: Nature Communications DOI: 10.1038/ncomms3795 Available at:
More Details
Authors: Ukhorskiy A Y, and Sitnov M I
Title: Dynamics of Radiation Belt Particles
Abstract: This paper reviews basic concepts of particle dynamics underlying theoretical aspect of radiation belt modeling and data analysis. We outline the theory of adiabatic invariants of quasiperiodic Hamiltonian systems and derive the invariants of particle motion trapped in the radiation belts. We discuss how the nonlinearity of resonant interaction of particles with small-amplitude plasma waves, ubiquitous across the inner magnetosphere, can make particle motion stochastic. Long-term evolution of a stochastic system can be described by the Fokker-Plank (diffusion) equation. We derive the kinetic equation of particle diffusion in the invariant space and discuss its limitations and associated challenges which need to be addressed in forthcoming radiation belt models and data analysis.
Date: 11/2013 Publisher: Space Science Reviews Pages: 545-578 DOI: 10.1007/s11214-012-9938-5 Available at:
More Details
Authors: Schultz Colin
Title: Dynamics of the Earth's Radiation Belts and Inner Magnetosphere
Abstract: Trapped by Earth's magnetic field far above the planet's surface, the energetic particles that fill the radiation belts are a sign of the Sun's influence and a threat to our technological future. In the AGU monograph Dynamics of the Earth's Radiation Belts and Inner Magnetosphere, editors Danny Summers, Ian R. Mann, Daniel N. Baker, and Michael Schulz explore the inner workings of the magnetosphere. The book reviews current knowledge of the magnetosphere and recent research results and sets the stage for the work currently being done by NASA's Van Allen Probes (formerly known as the Radiation Belt Storm Probes). In this interview, Eos talks to Summers about magnetospheric research, whistler mode waves, solar storms, and the effects of the radiation belts on Earth.
Date: 12/2013 Publisher: Eos, Transactions American Geophysical Union Pages: 509 - 509 DOI: 10.1002/eost.v94.5210.1002/2013EO520007 Available at:
More Details
Authors: Maurer Richard, Goldsten J O, Peplowski P N, Holmes-Siedle A G, Butler Michael, et al.
Title: Early Results from the Engineering Radiation Monitor (ERM) and Solar Cell Monitor on the Van Allen Probes Mission
Abstract: The Engineering Radiation Monitor (ERM) measures dose, dose rate and charging currents on the Van Allen Probes mission to study the dynamics of earth's Van Allen radiation belts. Early results from this monitor show a variation in dose rates with time, a correlation between the dosimeter and charging current data, a map of charging current versus orbit altitude and a comparison of cumulative dose to pre-launch modeling after 260 days. Solar cell degradation monitor patches track the decrease in solar array output as displacement damage accumulates.
Date: 11/2013 Publisher: IEEE DOI: 10.1109/TNS.2013.2281937 Available at:
More Details
Authors: Kletzing C A, Kurth W S, Acuna M, MacDowall R J, Torbert R B, et al.
Title: The Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) on RBSP
Abstract: The Electric and Magnetic Field Instrument and Integrated Science (EMFISIS) investigation on the NASA Radiation Belt Storm Probes (now named the Van Allen Probes) mission provides key wave and very low frequency magnetic field measurements to understand radiation belt acceleration, loss, and transport. The key science objectives and the contribution that EMFISIS makes to providing measurements as well as theory and modeling are described. The key components of the instruments suite, both electronics and sensors, including key functional parameters, calibration, and performance, demonstrate that EMFISIS provides the needed measurements for the science of the RBSP mission. The EMFISIS operational modes and data products, along with online availability and data tools provide the radiation bel. . .
Date: 11/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-013-9993-6 Available at:
More Details
Authors: Wygant J R, Bonnell J W, Goetz K, Ergun R E, Mozer F S, et al.
Title: The Electric Field and Waves (EFW) Instruments on the Radiation Belt Storm Probes Mission
Abstract: The Electric Fields and Waves (EFW) Instruments on the two Radiation Belt Storm Probe (RBSP) spacecraft (recently renamed the Van Allen Probes) are designed to measure three dimensional quasi-static and low frequency electric fields and waves associated with the major mechanisms responsible for the acceleration of energetic charged particles in the inner magnetosphere of the Earth. For this measurement, the instrument uses two pairs of spherical double probe sensors at the ends of orthogonal centripetally deployed booms in the spin plane with tip-to-tip separations of 100 meters. The third component of the electric field is measured by two spherical sensors separated by ∼15 m, deployed at the ends of two stacer booms oppositely directed along the spin axis of the spacecraft. The instrume. . .
Date: 11/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-013-0013-7 Available at:
More Details
Authors: Reeves G D, Spence H E, Henderson M G, Morley S. K., Friedel R H W, et al.
Title: Electron Acceleration in the Heart of the Van Allen Radiation Belts
Abstract: The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth’s magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local acceleration). We report measurements from NASA’s Van Allen Radiation Belt Storm Probes that clearly distinguish between the two types of acceleration. The observed radial profiles of phase space density are characteristic of local acceleration in the heart of the radiation belt. . .
Date: 07/2013 Publisher: Science Pages: 991 - 994 DOI: 10.1126/science.1237743 Available at:
More Details
Authors: Goldsten J O, Maurer R H, Peplowski P N, Holmes-Siedle A G, Herrmann C C, et al.
Title: The Engineering Radiation Monitor for the Radiation Belt Storm Probes Mission
Abstract: An Engineering Radiation Monitor (ERM) has been developed as a supplementary spacecraft subsystem for NASA’s Radiation Belt Storm Probes (RBSP) mission. The ERM will monitor total dose and deep dielectric charging at each RBSP spacecraft in real time. Configured to take the place of spacecraft balance mass, the ERM contains an array of eight dosimeters and two buried conductive plates. The dosimeters are mounted under covers of varying shielding thickness to obtain a dose-depth curve and characterize the electron and proton contributions to total dose. A 3-min readout cadence coupled with an initial sensitivity of ∼0.01 krad should enable dynamic measurements of dose rate throughout the 9-hr RBSP orbit. The dosimeters are Radiation-sensing Field Effect Transistors (RadFETs) and operate. . .
Date: 11/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-012-9917-x Available at:
More Details
Authors: Thorne R M, Li W, Ni B, Ma Q, Bortnik J, et al.
Title: Evolution and slow decay of an unusual narrow ring of relativistic electrons near L ~ 3.2 following the September 2012 magnetic storm
Abstract: A quantitative analysis is performed on the decay of an unusual ring of relativistic electrons between 3 and 3.5 RE, which was observed by the Relativistic Electron Proton Telescope instrument on the Van Allen probes. The ring formed on 3 September 2012 during the main phase of a magnetic storm due to the partial depletion of the outer radiation belt for L > 3.5, and this remnant belt of relativistic electrons persisted at energies above 2 MeV, exhibiting only slow decay, until it was finally destroyed during another magnetic storm on 1 October. This long-term stability of the relativistic electron ring was associated with the rapid outward migration and maintenance of the plasmapause to distances greater than L = 4. The remnant ring was thus immune from the dynamic process, whic. . .
Date: 06/2013 Publisher: Geophysical Research Letters DOI: 10.1002/grl.50627 Available at:
More Details
Authors: Dai L, Takahashi K, Wygant J R, Chen L, Bonnell J W, et al.
Title: Excitation of Poloidal standing Alfven waves through the drift resonance wave-particle interaction
Abstract: Drift-resonance wave-particle interaction is a fundamental collisionless plasma process studied extensively in theory. Using cross-spectral analysis of electric field, magnetic field, and ion flux data from the Van Allen Probe (Radiation Belt Storm Probes) spacecraft, we present direct evidence identifying the generation of a fundamental mode standing poloidal wave through drift-resonance interactions in the inner magnetosphere. Intense azimuthal electric field (Eφ) oscillations as large as 10mV/m are observed, associated with radial magnetic field (Br) oscillations in the dawn-noon sector near but south of the magnetic equator at L∼5. The observed wave period, Eφ/Br ratio and the 90° phase lag between Br and Eφ are all consistent with fundamental mode standing Poloidal waves. Phase . . .
Date: 08/2013 Publisher: Geophysical Research Letters DOI: 10.1002/grl.50800 Available at:
More Details
Authors: Li X, Schiller Q., Blum L., Califf S., Zhao H., et al.
Title: First Results from CSSWE CubeSat: Characteristics of Relativistic Electrons in the Near-Earth Environment During the October 2012 Magnetic Storms
Abstract: Measurements from the Relativistic Electron and Proton Telescope integrated little experiment (REPTile) on board the Colorado Student Space Weather Experiment (CSSWE) CubeSat mission, which was launched into a highly inclined (65°) low Earth orbit, are analyzed along with measurements from the Relativistic Electron and Proton Telescope (REPT) and the Magnetic Electron Ion Spectrometer (MagEIS) instruments aboard the Van Allen Probes, which are in a low inclination (10°) geo-transfer-like orbit. Both REPT and MagEIS measure the full distribution of energetic electrons as they traverse the heart of the outer radiation belt. However, due to the small equatorial loss cone (only a few degrees), it is difficult for REPT and MagEIS to directly determine which electrons will precipitate into the. . .
Date: 10/2013 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2013JA019342 Available at:
More Details
Authors: Funsten H O, Skoug R M, Guthrie A A, MacDonald E A, Baldonado J R, et al.
Title: Helium, Oxygen, Proton, and Electron (HOPE) Mass Spectrometer for the Radiation Belt Storm Probes Mission
Abstract: The HOPE mass spectrometer of the Radiation Belt Storm Probes (RBSP) mission (renamed the Van Allen Probes) is designed to measure the in situ plasma ion and electron fluxes over 4π sr at each RBSP spacecraft within the terrestrial radiation belts. The scientific goal is to understand the underlying physical processes that govern the radiation belt structure and dynamics. Spectral measurements for both ions and electrons are acquired over 1 eV to 50 keV in 36 log-spaced steps at an energy resolution ΔE FWHM/E≈15 %. The dominant ion species (H+, He+, and O+) of the magnetosphere are identified using foil-based time-of-flight (TOF) mass spectrometry with channel electron multiplier (CEM) detectors. Angular measurements are derived using five polar pixels coplanar with the spacecraft spin. . .
Date: 08/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-013-9968-7 Available at:
More Details
Authors: Baker D N, Hoxie V C, Jaynes A., Kale A., Kanekal S G, et al.
Title: James Van Allen and His Namesake NASA Mission
Abstract: In many ways, James A. Van Allen defined and “invented” modern space research. His example showed the way for government-university partners to pursue basic research that also served important national and international goals. He was a tireless advocate for space exploration and for the role of space science in the spectrum of national priorities.
Date: 12/2013 Publisher: Eos, Transactions American Geophysical Union Pages: 469 - 470 DOI: 10.1002/eost.v94.4910.1002/2013EO490001 Available at:
More Details
Authors: Smith Evan J., Butler Michael H., Fretz Kristin, and Wilhelm Benjamin
Title: Lithium Ion Battery Fault Management on the Van Allen Probes
Abstract: The Van Allen Probes (formerly known as the Radiation Belt Storm Probes or RBSP) mission launched on 30 August 2012 as part of NASA’s Living With a Star (LWS) Program. The ultimate goal of the mission is to understand how populations of relativistic electrons and penetrating ions in the Earth’s Van Allen Radiation Belts are affected by the Sun. The mission consists of two nearly identical observatories orbiting in highly-elliptical Earth orbits. The two satellite system allows for the study of the spatial and temporal effects the Sun has on the Earth’s radiation belts. Each observatory is equipped with a suite of instruments designed to continuously study ions, electrons and the local magnetic and electric fields. A brief overview of the Van Allen Probe mission is pre. . .
Date: 09/2013 Publisher: American Institute of Aeronautics and Astronautics DOI: 10.2514/6.2013-5526 Available at:
More Details
Authors: Baker D N, Kanekal S G, Hoxie V C, Henderson M G, Li X, et al.
Title: A Long-Lived Relativistic Electron Storage Ring Embedded in Earth's Outer Van Allen Belt
Abstract: Since their discovery more than 50 years ago, Earth’s Van Allen radiation belts have been considered to consist of two distinct zones of trapped, highly energetic charged particles. The outer zone is composed predominantly of megaelectron volt (MeV) electrons that wax and wane in intensity on time scales ranging from hours to days, depending primarily on external forcing by the solar wind. The spatially separated inner zone is composed of commingled high-energy electrons and very energetic positive ions (mostly protons), the latter being stable in intensity levels over years to decades. In situ energy-specific and temporally resolved spacecraft observations reveal an isolated third ring, or torus, of high-energy (>2 MeV) electrons that formed on 2 September 2012 and persisted largely unc. . .
Date: 04/2013 Publisher: Science Pages: 186-190 DOI: 10.1126/science.1233518 Available at:
More Details
Authors: Blake J B, Carranza P A, Claudepierre S G, Clemmons J H, Crain W R, et al.
Title: The Magnetic Electron Ion Spectrometer (MagEIS) Instruments Aboard the Radiation Belt Storm Probes (RBSP) Spacecraft
Abstract: This paper describes the Magnetic Electron Ion Spectrometer (MagEIS) instruments aboard the RBSP spacecraft from an instrumentation and engineering point of view. There are four magnetic spectrometers aboard each of the two spacecraft, one low-energy unit (20–240 keV), two medium-energy units (80–1200 keV), and a high-energy unit (800–4800 keV). The high unit also contains a proton telescope (55 keV–20 MeV). The magnetic spectrometers focus electrons within a selected energy pass band upon a focal plane of several silicon detectors where pulse-height analysis is used to determine if the energy of the incident electron is appropriate for the electron momentum selected by the magnet. Thus each event is a two-parameter analysis, an approach leading to a greatly reduced background. . . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 383-421 DOI: 10.1007/s11214-013-9991-8
More Details
Authors: Mozer F, Bale S., Bonnell J W, Chaston C., Roth I, et al.
Title: Megavolt Parallel Potentials Arising from Double-Layer Streams in the Earth’s Outer Radiation Belt
Abstract: Huge numbers of double layers carrying electric fields parallel to the local magnetic field line have been observed on the Van Allen probes in connection with in situ relativistic electron acceleration in the Earth’s outer radiation belt. For one case with adequate high time resolution data, 7000 double layers were observed in an interval of 1 min to produce a 230 000 V net parallel potential drop crossing the spacecraft. Lower resolution data show that this event lasted for 6 min and that more than 1 000 000 volts of net parallel potential crossed the spacecraft during this time. A double layer traverses the length of a magnetic field line in about 15 s and the orbital motion of the spacecraft perpendicular to the magnetic field was about 700 km during this 6 min interval. Thus, t. . .
Date: 12/2013 Publisher: Physical Review Letters DOI: 10.1103/PhysRevLett.111.235002 Available at:
More Details
Authors: Stratton J M, Harvey R J, and Heyler G A
Title: Mission Overview for the Radiation Belt Storm Probes Mission
Abstract: Provided here is an overview of Radiation Belt Storm Probes (RBSP) mission design. The driving mission and science requirements are presented, and the unique engineering challenges of operating in Earth’s radiation belts are discussed in detail. The implementation of both the space and ground segments are presented, including a discussion of the challenges inherent with operating multiple observatories concurrently and working with a distributed network of science operation centers. An overview of the launch vehicle and the overall mission design will be presented, and the plan for space weather data broadcast will be introduced.
Date: 01/2013 Publisher: Space Science Reviews DOI: 10.1007/s11214-012-9933-x Available at:
More Details
Authors: Blum L. W., Schiller Q., Li X, Millan R., Halford A., et al.
Title: New conjunctive CubeSat and balloon measurements to quantify rapid energetic electron precipitation
Abstract: Relativistic electron precipitation into the atmosphere can contribute significant losses to the outer radiation belt. In particular, rapid narrow precipitation features termed precipitation bands have been hypothesized to be an integral contributor to relativistic electron precipitation loss, but quantification of their net effect is still needed. Here we investigate precipitation bands as measured at low earth orbit by the Colorado Student Space Weather Experiment (CSSWE) CubeSat. Two precipitation bands of MeV electrons were observed on 18–19 January 2013, concurrent with precipitation seen by the 2013 Balloon Array for Radiation belt Relativistic Electron Losses (BARREL) campaign. The newly available conjugate measurements allow for a detailed estimate of the temporal and spatial fea. . .
Date: 11/2013 Publisher: Geophysical Research Letters Pages: 5833 - 5837 DOI: 10.1002/2013GL058546 Available at:
More Details
Authors: Min Kyungguk, Bortnik J, and Lee Jeongwoo
Title: A novel technique for rapid L* calculation using UBK coordinates
Abstract: [1] The magnetic drift invariant (L*) is an important quantity used for tracking and organizing particle dynamics in the radiation belts, but its accurate calculation has been computationally expensive in the past, thus making it difficult to employ this quantity in real-time space weather applications. In this paper, we propose a new, efficient method to calculate L* using the principle of energy conservation. This method uses Whipple's (U, B, K) coordinates to quickly and accurately determine trajectories of particles at the magnetic mirror point from two-dimensional isoenergy contours. The method works for any magnetic field configuration and is able to accommodate constant electric potential along field lines. We compare the result of this method with those of International Radiation B. . .
Date: 01/2013 Publisher: Journal of Geophysical Research DOI: 10.1029/2012JA018177
More Details
Authors: Min Kyungguk, Bortnik J, and Lee Jeongwoo
Title: A novel technique for rapid L∗ calculation: algorithm and implementation
Abstract: Computing the magnetic drift invariant, L*, rapidly and accurately has always been a challenge to magnetospheric modelers, especially given the im- portance of this quantity in the radiation belt community. Min et al. (2013) proposed a new method of calculating L* using the principle of energy con- servation. Continuing with the approach outlined therein, the present pa- per focuses on the technical details of the algorithm to outline the implemen- tation, systematic analysis of accuracy, and verification of the speed of the new method. We also show new improvements which enable near real-time computation of L*. The relative error is on the order of 10−3 when ∼ 0.1 RE grid resolution is used and the calculation speed is about two seconds per particle in the popular Tsyganenko. . .
Date: 05/2013 Publisher: Journal of Geophysical Research Pages: 1912-1921 DOI: 10.1002/jgra.50250 Available at:
More Details
Authors: Zimbardo Gaetano
Title: A Particle Accelerator in the Radiation Belts
Abstract: Satellites in the radiation belts reveal plasma structures that can jumpstart the acceleration of electrons to very high energies.
Date: 11/2013 Publisher: Physics DOI: 10.1103/Physics.6.131 Available at:
More Details
Authors: Morley S. K., Henderson M G, Reeves G D, Friedel R H W, and Baker D N
Title: Phase Space Density matching of relativistic electrons using the Van Allen Probes: REPT results
Abstract: 1] Phase Space Density (PSD) matching can be used to identify the presence of nonadiabatic processes, evaluate accuracy of magnetic field models, or to cross-calibrate instruments. Calculating PSD in adiabatic invariant coordinates requires a global specification of the magnetic field. For a well specified global magnetic field, nonadiabatic processes or inadequate cross calibration will give a poor PSD match. We have calculated PSD(μ, K) for both Van Allen Probes using a range of models and compare these PSDs at conjunctions in L* (for given μ, K). We quantitatively assess the relative goodness of each model for radiation belt applications. We also quantify the uncertainty in the model magnetic field magnitude and the related uncertainties in PSD, which has applications for modeling and. . .
Date: 09/2013 Publisher: Geophysical Research Letters Pages: 4798–4802 DOI: 10.1002/grl.50909 Available at:
More Details
Authors: Fox N J, and Burch J L
Title: Preface
Abstract: The discovery of the Van Allen radiation belts in 1958, starting with data from the United States’ first two successful orbiting spacecraft, Explorer’s I and III, was an astounding surprise and represented the founding of what we now call magnetospheric physics. Since that time many spacecraft have traversed the radiation belts en route to other more distant parts of Earth’s magnetosphere and other worlds beyond Earth’s orbit. After initial climatological models of the radiation belts were obtained in the 1960’s and early 1970’s, the main concern about them was the ability of spacecraft and astronauts to survive their intense radiation. And yet there were true scientific mysteries to be solved, glimpses of which came in the 1990’s from spacecraft like CRRES and SAMPEX. CRRES . . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 1-2 DOI: 10.1007/s11214-013-9997-2 Available at:
More Details
Authors: Mitchell D G, Lanzerotti L J, Kim C K, Stokes M, Ho G, et al.
Title: Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE)
Abstract: The Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE) on the two Van Allen Probes spacecraft is the magnetosphere ring current instrument that will provide data for answering the three over-arching questions for the Van Allen Probes Program: RBSPICE will determine “how space weather creates the storm-time ring current around Earth, how that ring current supplies and supports the creation of the radiation belt populations,” and how the ring current is involved in radiation belt losses. RBSPICE is a time-of-flight versus total energy instrument that measures ions over the energy range from ∼20 keV to ∼1 MeV. RBSPICE will also measure electrons over the energy range ∼25 keV to ∼1 MeV in order to provide instrument background information in the radiation belts. A des. . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 263-308 DOI: 10.1007/s11214-013-9965-x Available at:
More Details
Authors: Kessel R L, Fox N J, and Weiss M
Title: The Radiation Belt Storm Probes (RBSP) and Space Weather
Abstract: Following the launch and commissioning of NASA’s Radiation Belt Storm Probes (RBSP) in 2012, space weather data will be generated and broadcast from the spacecraft in near real-time. The RBSP mission targets one part of the space weather chain: the very high energy electrons and ions magnetically trapped within Earth’s radiation belts. The understanding gained by RBSP will enable us to better predict the response of the radiation belts to solar storms in the future, and thereby protect space assets in the near-Earth environment. This chapter details the presently planned RBSP capabilities for generating and broadcasting near real-time space weather data, discusses the data products, the ground stations collecting the data, and the users/models that will incorporate the data into test-b. . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 531-543 DOI: 10.1007/s11214-012-9953-6 Available at:
More Details
Authors: Turney D, Matiella Novak A, Beisser K, and Fox N
Title: Radiation Belt Storm Probes (RBSP) Education and Public Outreach Program
Abstract: The Radiation Belt Storm Probes (RBSP) Education and Public Outreach (E/PO) program serves as a pipeline of activities to inspire and educate a broad audience about Heliophysics and the Sun-Earth system, specifically the Van Allen Radiation Belts. The program is comprised of a variety of formal, informal and public outreach activities that all align with the NASA Education Portfolio Strategic Framework outcomes. These include lesson plans and curriculum for use in the classroom, teacher workshops, internship opportunities, activities that target underserved populations, collaboration with science centers and NASA visitors’ centers and partnerships with experts in the Heliophysics and education disciplines. This paper will detail the activities that make up the RBSP E/PO program, their in. . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 617-646 DOI: 10.1007/s11214-012-9945-6 Available at:
More Details
Authors: Kirby Karen, Artis David, Bushman Stewart, Butler Michael, Conde Rich, et al.
Title: Radiation Belt Storm Probes—Observatory and Environments
Abstract: The National Aeronautics and Space Administration’s (NASA’s) Radiation Belt Storm Probe (RBSP) is an Earth-orbiting mission that launched August 30, 2012, and is the latest science mission in NASA’s Living with a Star Program. The RBSP mission will investigate, characterize and understand the physical dynamics of the radiation belts, as well as the influence of the Sun on the Earth’s environment, by measuring particles, electric and magnetic fields and waves that comprise geospace. The mission is composed of two identically instrumented spinning observatories in an elliptical orbit around earth with 600 km perigee, 30,000 km apogee and 10∘ inclination to provide full sampling of the Van Allen radiation belts. The twin RBSP observatories (recently renamed the Van Allen Probes) wil. . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 59-125 DOI: 10.1007/s11214-012-9949-2 Available at:
More Details
Authors: Ukhorskiy A Y, Sitnov M I, Merkin V. G., and Artemyev A. V.
Title: Rapid acceleration of protons upstream of earthward propagating dipolarization fronts
Abstract: [1] Transport and acceleration of ions in the magnetotail largely occurs in the form of discrete impulsive events associated with a steep increase of the tail magnetic field normal to the neutral plane (Bz), which are referred to as dipolarization fronts. The goal of this paper is to investigate how protons initially located upstream of earthward moving fronts are accelerated at their encounter. According to our analytical analysis and simplified two-dimensional test-particle simulations of equatorially mirroring particles, there are two regimes of proton acceleration: trapping and quasi-trapping, which are realized depending on whether the front is preceded by a negative depletion in Bz. We then use three-dimensional test-particle simulations to investigate how these acceleration processe. . .
Date: 01/2013 Publisher: Journal of Geophysical Research: Space Physics Pages: 4952–4962, DOI: 10.1002/jgra.50452 Available at:
More Details
Authors: Thorne R M, Li W, Ni B, Ma Q, Bortnik J, et al.
Title: Rapid local acceleration of relativistic radiation-belt electrons by magnetospheric chorus
Abstract: Recent analysis of satellite data obtained during the 9 October 2012 geomagnetic storm identified the development of peaks in electron phase space density1, which are compelling evidence for local electron acceleration in the heart of the outer radiation belt2, 3, but are inconsistent with acceleration by inward radial diffusive transport4, 5. However, the precise physical mechanism responsible for the acceleration on 9 October was not identified. Previous modelling has indicated that a magnetospheric electromagnetic emission known as chorus could be a potential candidate for local electron acceleration6, 7, 8, 9, 10, but a definitive resolution of the importance of chorus for radiation-belt acceleration was not possible because of limitations in the energy range and resolution of previous. . .
Date: 12/2013 Publisher: Nature Pages: 411 - 414 DOI: 10.1038/nature12889 Available at:
More Details
Authors: Baker D N, Kanekal S G, Hoxie V C, Batiste S, Bolton M, et al.
Title: The Relativistic Electron-Proton Telescope (REPT) Instrument on Board the Radiation Belt Storm Probes (RBSP) Spacecraft: Characterization of Earth’s Radiation Belt High-Energy Particle Populations
Abstract: Particle acceleration and loss in the million electron Volt (MeV) energy range (and above) is the least understood aspect of radiation belt science. In order to measure cleanly and separately both the energetic electron and energetic proton components, there is a need for a carefully designed detector system. The Relativistic Electron-Proton Telescope (REPT) on board the Radiation Belt Storm Probe (RBSP) pair of spacecraft consists of a stack of high-performance silicon solid-state detectors in a telescope configuration, a collimation aperture, and a thick case surrounding the detector stack to shield the sensors from penetrating radiation and bremsstrahlung. The instrument points perpendicular to the spin axis of the spacecraft and measures high-energy electrons (up to ∼20 MeV) with exc. . .
Date: 11/2013 Publisher: Space Science Reviews Pages: 337-381 DOI: 10.1007/s11214-012-9950-9 Available at:
More Details