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James Van Allen And His Namesake Nasa Mission, D. N. Baker, V. C. Hoxie, A. Jaynes, A. Kale, S. G. Kanekal, X. Li, Geoffrey Reeves, Harlan E. Spence
James Van Allen And His Namesake Nasa Mission, D. N. Baker, V. C. Hoxie, A. Jaynes, A. Kale, S. G. Kanekal, X. Li, Geoffrey Reeves, Harlan E. Spence
Physics & Astronomy
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.
Science Goals And Overview Of The Radiation Belt Storm Probes (Rbsp) Energetic Particle, Composition, And Thermal Plasma (Ect) Suite On Nasa’S Van Allen Probes Mission, Harlan E. Spence, G. D. Reeves, D. N. Baker, J. B. Blake, M. Bolton, S. Bourdarie, A. A. Chan, S. G. Claudepierre, J. H. Clemmons, J. P. Cravens, S. R. Elkington, J. F. Fennell
Science Goals And Overview Of The Radiation Belt Storm Probes (Rbsp) Energetic Particle, Composition, And Thermal Plasma (Ect) Suite On Nasa’S Van Allen Probes Mission, Harlan E. Spence, G. D. Reeves, D. N. Baker, J. B. Blake, M. Bolton, S. Bourdarie, A. A. Chan, S. G. Claudepierre, J. H. Clemmons, J. P. Cravens, S. R. Elkington, J. F. Fennell
Physics & Astronomy
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 the inner magnetosphere and radiation belts. The coordinated RBSP-ECT particle measurements, analyzed in combination with fields and waves observations and state-of-the-art theory and modeling, are necessary for understanding the acceleration, global distribution, and variability of radiation belt electrons and ions, key science objectives of NASA’s Living With a Star program and the Van Allen Probes mission. The RBSP-ECT suite consists of three highly-coordinated instruments: the Magnetic Electron Ion Spectrometer (MagEIS), the …
The Magnetic Electron Ion Spectrometer (Mageis) Instruments Aboard The Radiation Belt Storm Probes (Rbsp) Spacecraft, J. B. Blake, P. A. Carranza, S. G. Claudepierre, J. H. Clemmons, W. R. Crain, Y. Dotan, J. F. Fennell, F. H. Fuentes, R. M. Galvan, J. S. George, M. G. Henderson, M. Lalic
The Magnetic Electron Ion Spectrometer (Mageis) Instruments Aboard The Radiation Belt Storm Probes (Rbsp) Spacecraft, J. B. Blake, P. A. Carranza, S. G. Claudepierre, J. H. Clemmons, W. R. Crain, Y. Dotan, J. F. Fennell, F. H. Fuentes, R. M. Galvan, J. S. George, M. G. Henderson, M. Lalic
Physics & Astronomy
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 …
Helium, Oxygen, Proton, And Electron (Hope) Mass Spectrometer For The Radiation Belt Storm Probes Mission, H. O. Funsten, R. M. Skoug, A. A. Guthrie, E. A. Macdonald, J. R. Baldonado, R. W. Harper, K. C. Henderson, K. H. Kihara, J. E. Lake, B. A. Larsen, A. D. Puckett, V. J. Vigil, Harlan E. Spence
Helium, Oxygen, Proton, And Electron (Hope) Mass Spectrometer For The Radiation Belt Storm Probes Mission, H. O. Funsten, R. M. Skoug, A. A. Guthrie, E. A. Macdonald, J. R. Baldonado, R. W. Harper, K. C. Henderson, K. H. Kihara, J. E. Lake, B. A. Larsen, A. D. Puckett, V. J. Vigil, Harlan E. Spence
Physics & Astronomy
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 …
Revision Of Empirical Electric Field Modeling In The Inner Magnetosphere Using Cluster Data, Hiroshi Matsui, Harlan E. Spence, Y. V. Khotyaintsev, P. A. Lindqvist
Revision Of Empirical Electric Field Modeling In The Inner Magnetosphere Using Cluster Data, Hiroshi Matsui, Harlan E. Spence, Y. V. Khotyaintsev, P. A. Lindqvist
Physics & Astronomy
Using Cluster data from the Electron Drift (EDI) and the Electric Field and Wave (EFW) instruments, we revise our empirically-based, inner-magnetospheric electric field (UNH-IMEF) model at 22.662 mV/m; K-p<1, 1K(p)<2, 2K(p)<3, 3K(p)<4, 4K(p)<5, and K(p)4(+). Patterns consist of one set of data and processing for smaller activities, and another for higher activities. As activity increases, the skewed potential contour related to the partial ring current appears on the nightside. With the revised analysis, we find that the skewed potential contours get clearer and potential contours get denser on the nightside and morningside. Since the fluctuating components are not negligible, standard deviations from the modeled values are included in the model. In this study, we perform validation of the derived model more extensively. We find experimentally that the skewed contours are located close to the last closed equipotential, consistent with previous theories. This gives physical context to our model and serves as one validation effort. As another validation effort, the derived results are compared with other models/measurements. From these comparisons, we conclude that our model has some clear advantages over the others.
Measurements Of Galactic Cosmic Ray Shielding With The Crater Instrument, C. Zeitlin, A. W. Case, Harlan E. Spence, Nathan A. Schwadron, M. Golightly, Jody K. Wilson, J. C. Kasper, J. B. Blake, M. D. Looper, J. E. Mazur, L. W. Townsend, Y. Iwata
Measurements Of Galactic Cosmic Ray Shielding With The Crater Instrument, C. Zeitlin, A. W. Case, Harlan E. Spence, Nathan A. Schwadron, M. Golightly, Jody K. Wilson, J. C. Kasper, J. B. Blake, M. D. Looper, J. E. Mazur, L. W. Townsend, Y. Iwata
Physics & Astronomy
[1] The Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument aboard the Lunar Reconnaissance Orbiter has been measuring energetic charged particles from the galactic cosmic rays (GCRs) and solar particle events in lunar orbit since 2009. CRaTER includes three pairs of silicon detectors, separated by pieces of tissue-equivalent plastic that shield two of the three pairs from particles incident at the zenith-facing end of the telescope. Heavy-ion beams studied in previous ground-based work have been shown to be reasonable proxies for the GCRs when their energies are sufficiently high. That work, which included GCR simulations, led to predictions …
Early Science Results From The Nasa Van Allen Probes Mission Rbsp-Ect Instrument Suite, Harlan E. Spence, Geoff Reeves, Rbspect Team
Early Science Results From The Nasa Van Allen Probes Mission Rbsp-Ect Instrument Suite, Harlan E. Spence, Geoff Reeves, Rbspect Team
Physics & Astronomy
No abstract provided.
The Radiation Environment Near The Lunar Surface: Crater Observations And Geant4 Simulations, M. D. Looper, J. E. Mazur, J. B. Blake, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, A. W. Case, J. C. Kasper, L. W. Townsend
The Radiation Environment Near The Lunar Surface: Crater Observations And Geant4 Simulations, M. D. Looper, J. E. Mazur, J. B. Blake, Harlan E. Spence, Nathan A. Schwadron, M. J. Golightly, A. W. Case, J. C. Kasper, L. W. Townsend
Physics & Astronomy
[1] At the start of the Lunar Reconnaissance Orbiter mission in 2009, its Cosmic Ray Telescope for the Effects of Radiation instrument measured the radiation environment near the Moon during the recent deep solar minimum, when galactic cosmic rays (GCRs) were at the highest level observed during the space age. We present observations that show the combined effects of GCR primaries, secondary particles (“albedo”) created by the interaction of GCRs with the lunar surface, and the interactions of these particles in the shielding material overlying the silicon solid-state detectors of the Cosmic Ray Telescope for the Effects of Radiation. We …
New Insight Into The Inner Magnetosphere Plasma Regimes With The Van Allen Probes (Rbsp), Joerg-Micha Jahn, Richard E. Denton, Herbert O. Funsten, Geoff Reeves, Harlan E. Spence
New Insight Into The Inner Magnetosphere Plasma Regimes With The Van Allen Probes (Rbsp), Joerg-Micha Jahn, Richard E. Denton, Herbert O. Funsten, Geoff Reeves, Harlan E. Spence
Physics & Astronomy
No abstract provided.
Towards In Situ Correlation Of Atomic Structure And Device Functionality In Graphene-Based Devices, Shawna M. Hollen, N M. Santagata, Justin R. Young, Jay A. Gupta, Ezekiel Johnston-Halperin
Towards In Situ Correlation Of Atomic Structure And Device Functionality In Graphene-Based Devices, Shawna M. Hollen, N M. Santagata, Justin R. Young, Jay A. Gupta, Ezekiel Johnston-Halperin
Physics & Astronomy
No abstract provided.
Transport Behavior Of Ultrathin Films With Nanothickness Undulations In The Strongly Localized Regime, J C. Joy, Shawna M. Hollen, C Zhao, G. E. Fernandes, J M. Xu, J M. Valles Jr.
Transport Behavior Of Ultrathin Films With Nanothickness Undulations In The Strongly Localized Regime, J C. Joy, Shawna M. Hollen, C Zhao, G. E. Fernandes, J M. Xu, J M. Valles Jr.
Physics & Astronomy
No abstract provided.
Observation Of The Collapse Of The Cooper Pair Phase Coherence Length At A Superconductor To Insulator Transition, J M. Valles Jr., Shawna M. Hollen, G. E. Fernandes, Jimmy Xu
Observation Of The Collapse Of The Cooper Pair Phase Coherence Length At A Superconductor To Insulator Transition, J M. Valles Jr., Shawna M. Hollen, G. E. Fernandes, Jimmy Xu
Physics & Astronomy
No abstract provided.
Collapse Of The Cooper Pair Phase Coherence Length At A Superconductor-To-Insulator Transition, Shawna M. Hollen, G. E. Fernandes, J. M. Xu, J M. Valles Jr.
Collapse Of The Cooper Pair Phase Coherence Length At A Superconductor-To-Insulator Transition, Shawna M. Hollen, G. E. Fernandes, J. M. Xu, J M. Valles Jr.
Physics & Astronomy
We present investigations of the superconductor-to-insulator transition (SIT) of uniform a-Bi films using a technique sensitive to Cooper pair phase coherence. The films are perforated with a nanohoneycomb array of holes to form a multiply connected geometry and subjected to a perpendicular magnetic field. Film magnetoresistances on the superconducting side of the SIT oscillate with a period dictated by the superconducting flux quantum and the areal hole density. The oscillations disappear close to the SIT critical point to leave a monotonically rising magnetoresistance that persists in the insulating phase. These observations indicate that the Cooper pair phase coherence length, which …
The Crater Special Issue Of Space Weather: Building The Observational Foundation To Deduce Biological Effects Of Space Radiation, Nathan A. Schwadron, Sonya S. Smith, Harlan E. Spence
The Crater Special Issue Of Space Weather: Building The Observational Foundation To Deduce Biological Effects Of Space Radiation, Nathan A. Schwadron, Sonya S. Smith, Harlan E. Spence
Physics & Astronomy
[1] The United States is preparing for exploration beyond low-Earth Orbit (LEO). However, the space radiation environment poses significant risks. The radiation hazard is potentially severe but not sufficiently well characterized to determine if long missions outside LEO can be accomplished with acceptable risk [Cucinotta et al., 2001; Schwadron et al., 2010; Cucinotta et al., 2010]. Radiation hazards may be over- or under-stated through incomplete characterization in terms of net quantities such as accumulated dose. Time-dependent characterization often changes acute risk estimates [NCRP, 1989; Cucinotta, 1999; Cucinotta et al., 2000; George et al., 2002]. For example, events with high accumulated …