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Authors: Nunn David, and Omura Yoshiharu
Title: A computational and theoretical investigation of nonlinear wave-particle interactions in oblique whistlers
Abstract: Most previous work on nonlinear wave-particle interactions between energetic electrons and VLF waves in the Earth's magnetosphere has assumed parallel propagation, the underlying mechanism being nonlinear trapping of cyclotron resonant electrons in a parabolic magnetic field inhomogeneity. Here nonlinear wave-particle interaction in oblique whistlers in the Earth's magnetosphere is investigated. The study is nonself-consistent and assumes an arbitrarily chosen wave field. We employ a “continuous wave” wave field with constant frequency and amplitude, and a model for an individual VLF chorus element. We derive the equations of motion and trapping conditions in oblique whistlers. The resonant particle distribution function, resonant current, and nonlinear growth rate are computed as func. . .
Date: 04/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020898 Available at: http://doi.wiley.com/10.1002/2014JA020898
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Authors: Nosé M., Oimatsu S., Keika K, Kletzing C A, Kurth W S, et al.
Title: Formation of the oxygen torus in the inner magnetosphere: Van Allen Probes observations
Abstract: We study the formation process of an oxygen torus during the 12–15 November 2012 magnetic storm, using the magnetic field and plasma wave data obtained by Van Allen Probes. We estimate the local plasma mass density (ρL) and the local electron number density (neL) from the resonant frequencies of standing Alfvén waves and the upper hybrid resonance band. The average ion mass (M) can be calculated by M ∼ ρL/neL under the assumption of quasi-neutrality of plasma. During the storm recovery phase, both Probe A and Probe B observe the oxygen torus at L = 3.0–4.0 and L = 3.7–4.5, respectively, on the morning side. The oxygen torus has M = 4.5–8 amu and extends around the plasmapause that is identified at L∼3.2–3.9. We find that during the initial phase, M is 4–7 amu throughout . . .
Date: 02/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020593 Available at: http://doi.wiley.com/10.1002/2014JA020593
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Authors: Nomura R., Shiokawa K., Omura Y., Ebihara Y., Miyoshi Y, et al.
Title: Pulsating proton aurora caused by rising tone Pc1 waves
Abstract: We found rising tone emissions with a dispersion of ∼1 Hz per several tens of seconds in the dynamic spectrum of a Pc1 geomagnetic pulsation (Pc1) observed on the ground. These Pc1 rising tones were successively observed over ∼30 min from 0250 UT on 14 October 2006 by an induction magnetometer at Athabasca, Canada (54.7°N, 246.7°E, magnetic latitude 61.7°N). Simultaneously, a Time History of Events and Macroscale Interactions during Substorms panchromatic (THEMIS) all-sky camera detected pulsations of an isolated proton aurora with a period of several tens of seconds, ∼10% variations in intensity, and fine structures of 3° in magnetic longitudes. The pulsations of the proton aurora close to the zenith of ATH have one-to-one correspondences with the Pc1 rising tones. This suggests. . .
Date: 02/2016 Publisher: Journal of Geophysical Research: Space Physics Pages: n/a - n/a DOI: 10.1002/2015JA021681 Available at: http://onlinelibrary.wiley.com/doi/10.1002/2015JA021681/full
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Authors: Noh Sung-Jun, Lee Dae-Young, Choi Cheong-Rim, Kim Hyomin, and Skoug Ruth
Title: Test of Ion Cyclotron Resonance Instability Using Proton Distributions Obtained From Van Allen Probe-A Observations
Abstract: Anisotropic velocity distributions of protons have long been considered as free energy sources for exciting electromagnetic ion cyclotron (EMIC) waves in the Earth's magnetosphere. Here we rigorously calculated the proton anisotropy parameter using proton data obtained from Van Allen Probe‐A observations. The calculations are performed for times during EMIC wave events (distinguishing the times immediately after and before EMIC wave onsets) and for times exhibiting no EMIC waves. We find that the anisotropy values are often larger immediately after EMIC wave onsets than the times just before EMIC wave onsets and the non‐EMIC wave times. The increase in anisotropy immediately after the EMIC wave onsets is rather small but discernible, such that the average increase is by ~15% relative t. . .
Date: 08/2018 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1029/2018JA025385 Available at: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018JA025385
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Authors: Nishimura Y., Bortnik J, Li W, Lyons L R, Donovan E. F., et al.
Title: Evolution of nightside subauroral proton aurora caused by transient plasma sheet flows
Abstract: While nightside subauroral proton aurora shows rapid temporal variations, the cause of this variability has rarely been investigated. Using well-coordinated observations by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) all-sky imagers, THEMIS satellites in the equatorial magnetosphere, and the low-altitude NOAA 17 satellite, we examined the rapid temporal evolution of subauroral proton aurora in the premidnight sector. An isolated proton aurora occurred soon after an auroral poleward boundary intensification that was followed by an auroral streamer reaching the equatorward boundary of the auroral oval. Three THEMIS satellites in the magnetotail detected flow bursts and one of the THEMIS satellites in the outer plasmasphere observed a ring current injectio. . .
Date: 07/2014 Publisher: Journal of Geophysical Research: Space Physics Pages: 5295 - 5304 DOI: 10.1002/2014JA020029 Available at: http://doi.wiley.com/10.1002/2014JA020029
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Authors: Nishi Katsuki, Shiokawa Kazuo, and Spence Harlan
Title: Magnetospheric source region of auroral finger-like structures observed by the RBSP-A satellite
Abstract: Auroral finger‐like structures appear equatorward of the auroral oval in the diffuse auroral region and contribute to the auroral fragmentation into patches. A previous report of the first conjugate observation of auroral finger‐like structures using a THEMIS GBO camera and the THEMIS‐E satellite at a radial distance of ∼8 RE showed anti‐phase oscillations of magnetic and plasma pressures in the dawnside plasma sheet. In the present study, we report another simultaneous observation of auroral finger‐like structures at Gillam, Canada at ∼0900 UT (0230 magnetic local time) on November 14, 2014 with the RBSP satellites at 5.8 RE in the inner magnetosphere. From this simultaneous observation event, we obtained the following observations. (1) Auroral finger‐like structures devel. . .
Date: 08/2018 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1029/2018JA025480 Available at: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018JA025480
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Authors: Nikoukar Romina, Bust Gary, and Murr David
Title: A novel data assimilation technique for the plasmasphere
Abstract: We present a novel technique for imaging and data assimilation of the topside ionosphere and plasmasphere. The methodology is based upon the 3 dimensional variational technique (3DVAR), where an empirical background model is utilized. However, to prevent non-physical vertical variation in density estimates, we devise statistical methods to enforce a roughness penalty in the traditional 3DVAR optimization. The upward looking total electron content (TEC) observations from the Global Positioning System (GPS) receiver onboard Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) satellites are utilized in the assimilation algorithm. The estimation results show reasonable agreement with in-situ density measurements of Defense Meteorological Satellite Program satellites. . .
Date: 09/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2015JA021455 Available at: http://onlinelibrary.wiley.com/wol1/doi/10.1002/2015JA021455/abstract
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Authors: Ni Binbin, Li Wen, Thorne Richard M, Bortnik Jacob, Green Janet C, et al.
Title: A novel technique to construct the global distribution of whistler mode chorus wave intensity using low-altitude POES electron data
Abstract: Although magnetospheric chorus plays a significant role in the acceleration and loss of radiation belt electrons, its global evolution during any specific time period cannot be directly obtained by spacecraft measurements. Using the low-altitude NOAA Polar-orbiting Operational Environmental Satellite (POES) electron data, we develop a novel physics-based methodology to infer the chorus wave intensity and construct its global distribution with a time resolution of less than an hour. We describe in detail how to apply the technique to satellite data by performing two representative analyses, i.e., (i) for one specific time point to visualize the estimation procedure and (ii) for a particular time period to validate the method and construct an illustrative global chorus wave model. We demonst. . .
Date: 07/2014 Publisher: Journal of Geophysical Research: Space Physics Pages: 5685 - 5699 DOI: 10.1002/jgra.v119.710.1002/2014JA019935 Available at: http://doi.wiley.com/10.1002/jgra.v119.7http://doi.wiley.com/10.1002/2014JA019935
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Authors: Ni Binbin, Zou Zhengyang, Li Xinlin, Bortnik Jacob, Xie Lun, et al.
Title: Occurrence Characteristics of Outer Zone Relativistic Electron Butterfly Distribution: A Survey of Van Allen Probes REPT Measurements
Abstract: Using Van Allen Probes REPT pitch angle resolved electron flux data from September 2012 to March 2015, we investigate in detail the global occurrence pattern of equatorial (|λ| ≤ 3°) butterfly distribution of outer zone relativistic electrons and its potential correlation with the solar wind dynamic pressure. The statistical results demonstrate that these butterfly distributions occur with the highest occurrence rate ~ 80% at ~ 20 – 04 MLT and L > ~ 5.5 and with the second peak (> ~ 50 %) at ~ 11 – 15 MLT of lower L-shells ~ 4.0. They can also extend to L = 3.5 and to other MLT intervals but with the occurrence rates predominantly < ~25%. It is further shown that outer zone relativistic electron butterfly distributions are likely to peak between . . .
Date: 05/2016 Publisher: Geophysical Research Letters DOI: 10.1002/2016GL069350 Available at: http://doi.wiley.com/10.1002/2016GL069350
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Authors: Ni Binbin, Bortnik Jacob, Thorne Richard M, Ma Qianli, and Chen Lunjin
Title: Resonant scattering and resultant pitch angle evolution of relativistic electrons by plasmaspheric hiss
Abstract: We perform a comprehensive analysis to evaluate hiss-induced scattering effect on the pitch angle evolution and associated decay processes of relativistic electrons. The results show that scattering by the equatorial, highly oblique hiss component is negligible. Quasi-parallel approximation is good for evaluation of hiss-driven electron scattering rates ≤ 2 MeV. However, realistic wave propagation angles as a function of latitude must be considered to accurately quantify hiss scattering rates above 2 MeV, and ambient plasma density is also a critical parameter. While the first-order cyclotron and the Landau resonances are dominant for hiss scattering < 2 MeV electrons, higher-order resonances become important and even dominant at intermediate pitch angles for ultrarelativistic (≥. . .
Date: 12/2013 Publisher: Journal of Geophysical Research: Space Physics Pages: 7740 - 7751 DOI: 10.1002/2013JA019260 Available at: http://doi.wiley.com/10.1002/2013JA019260
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Authors: Ni Binbin, Zou Zhengyang, Gu Xudong, Zhou Chen, Thorne Richard M, et al.
Title: Variability of the pitch angle distribution of radiation belt ultra-relativistic electrons during and following intense geomagnetic storms: Van Allen Probes observations
Abstract: Fifteen months of pitch angle resolved Van Allen Probes REPT measurements of differential electron flux are analyzed to investigate the characteristic variability of the pitch angle distribution (PAD) of radiation belt ultra-relativistic (>2 MeV) electrons during storm conditions and during the long-term post-storm decay. By modeling the ultra-relativistic electron pitch angle distribution as sinn α, where α is the equatorial pitch angle, we examine the spatio-temporal variations of the n-value. The results show that in general n-values increase with the level of geomagnetic activity. In principle, ultra-relativistic electrons respond to geomagnetic storms by becoming more peaked at 90° pitch angle with n-values of 2–3 as a supportive signature of chorus acceleration outside the pla. . .
Date: 05/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2015JA021065 Available at: http://doi.wiley.com/10.1002/2015JA021065
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Authors: Ni Binbin, Li Wen, Thorne Richard M, Bortnik Jacob, Ma Qianli, et al.
Title: Resonant scattering of energetic electrons by unusual low-frequency hiss
Abstract: We quantify the resonant scattering effects of the unusual low-frequency dawnside plasmaspheric hiss observed on 30 September 2012 by the Van Allen Probes. In contrast to normal (~100–2000 Hz) hiss emissions, this unusual hiss event contained most of its wave power at ~20–200 Hz. Compared to the scattering by normal hiss, the unusual hiss scattering speeds up the loss of ~50–200 keV electrons and produces more pronounced pancake distributions of ~50–100 keV electrons. It is demonstrated that such unusual low-frequency hiss, even with a duration of a couple of hours, plays a particularly important role in the decay and loss process of energetic electrons, resulting in shorter electron lifetimes for ~50–400 keV electrons than normal hiss, and should be carefully incorpora. . .
Date: 03/2014 Publisher: Geophysical Research Letters Pages: 1854 - 1861 DOI: 10.1002/2014GL059389 Available at: http://doi.wiley.com/10.1002/2014GL059389
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Authors: Ni Binbin, Zou Zhengyang, Fu Song, Cao Xing, Gu Xudong, et al.
Title: Resonant Scattering of Radiation Belt Electrons by Off-Equatorial Magnetosonic Waves
Abstract: Fast magnetosonic (MS) waves are commonly regarded as electromagnetic waves that are characteristically confined within ±3° of the geomagnetic equator. We report two typical off-equatorial MS events observed by Van Allen Probes, that is, the 8 May 2014 event that occurred at the geomagnetic latitudes of 7.5°–9.2° both inside and outside the plasmasphere with the wave amplitude up to 590 pT and the 9 January 2014 event that occurred at the latitudes of—(15.7°–17.5°) outside the plasmasphere with a smaller amplitude about 81 pT. Detailed test particle simulations quantify the electron resonant scattering rates by the off-equatorial MS waves to find that they can cause the pitch angle scattering and momentum diffusion of radiation belt electrons with equatorial pitch angles < ~75. . .
Date: 02/2018 Publisher: Geophysical Research Letters Pages: 1228 - 1236 DOI: 10.1002/grl.v45.310.1002/2017GL075788 Available at: http://onlinelibrary.wiley.com/doi/10.1002/2017GL075788/full
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Authors: Ni Binbin, Cao Xing, Zou Zhengyang, Zhou Chen, Gu Xudong, et al.
Title: Resonant scattering of outer zone relativistic electrons by multiband EMIC waves and resultant electron loss time scales
Abstract: To improve our understanding of the role of electromagnetic ion cyclotron (EMIC) waves in radiation belt electron dynamics, we perform a comprehensive analysis of EMIC wave-induced resonant scattering of outer zone relativistic (>0.5 MeV) electrons and resultant electron loss time scales with respect to EMIC wave band, L shell, and wave normal angle model. The results demonstrate that while H+-band EMIC waves dominate the scattering losses of ~1–4 MeV outer zone relativistic electrons, it is He+-band and O+-band waves that prevail over the pitch angle diffusion of ultrarelativistic electrons at higher energies. Given the wave amplitude, EMIC waves at higher L shells tend to resonantly interact with a larger population of outer zone relativistic electrons and drive their pitch angle s. . .
Date: 09/2015 Publisher: Journal of Geophysical Research: Space Physics Pages: 7357 - 7373 DOI: 10.1002/2015JA021466 Available at: http://doi.wiley.com/10.1002/2015JA021466http://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2F2015JA021466
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Authors: Newkirk L L, and Walt M
Title: Radial Diffusion Coefficient for Electrons at 1.76 < L < 5
Abstract: Radial diffusion by nonconservation of the third adiabatic invariant of particle motion is assumed in analyzing experiments in which electrons appeared to move across field lines. Time-dependent solutions of the Fokker-Planck diffusion equation are obtained numerically and fitted to the experimental results by adjusting the diffusion coefficient. Values deduced for the diffusion coefficient vary from 1.3 × 10−5 RE²/day at L = 1.76 to 0.10 RE²/day at L = 5. In the interval 2.6 < L < 5, the coefficient varies as L10±1. Assuming a constant electron source of arbitrary magnitude at L = 6 and the above diffusion coefficients, the equatorial equilibrium distribution is calculated for electrons with energies above 1.6 Mev. The calculation yields an outer belt of electrons whose radial distr. . .
Date: 12/1968 Publisher: Journal of Geophysical Research Pages: 7231 - 7236 DOI: 10.1029/JA073i023p07231 Available at: http://onlinelibrary.wiley.com/doi/10.1029/JA073i023p07231/abstract
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Authors: Newkirk L L, and Walt M
Title: Radial Diffusion Coefficient for Electrons at Low L Values
Abstract: An empirical evaluation of the diffusion coefficient for trapped electrons diffusing across low L shells is obtained by adjusting the coefficient to account for the observed radial profile and the long-term decay rate of the trapped electron flux. The diffusion mechanism is not identified, but it is assumed that the adiabatic invariants µ and J are conserved. The average value of the coefficient for electrons > 1.6 Mev energy is found to decrease monotonically from ∼4 × 10−6 RE²/day at L = 1.16 to ∼2 × 10−7 RE²/day at L = 1.20.
Date: 02/1968 Publisher: Journal of Geophysical Research Pages: 1013 - 1017 DOI: 10.1029/JA073i003p01013 Available at: http://onlinelibrary.wiley.com/doi/10.1029/JA073i003p01013/abstract
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Authors: Němec F., Santolik O, Hrbáčková Z., and Cornilleau-Wehrlin N.
Title: Intensities and spatiotemporal variability of equatorial noise emissions observed by the Cluster spacecraft
Abstract: Equatorial noise (EN) emissions are electromagnetic waves observed in the equatorial region of the inner magnetosphere at frequencies between the proton cyclotron frequency and the lower hybrid frequency. We present the analysis of 2229 EN events identified in the Spatio-Temporal Analysis of Field Fluctuations (STAFF) experiment data of the Cluster spacecraft during the years 2001–2010. EN emissions are distinguished using the polarization analysis, and their intensity is determined based on the evaluation of the Poynting flux rather than on the evaluation of only the electric/magnetic field intensity. The intensity of EN events is analyzed as a function of the frequency, the position of the spacecraft inside/outside the plasmasphere, magnetic local time, and the geomagnetic activity. Th. . .
Date: 03/2015 Publisher: Journal of Geophysical Research: Space Physics Pages: 1620 - 1632 DOI: 10.1002/2014JA020814 Available at: http://doi.wiley.com/10.1002/2014JA020814
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Authors: Němec F., Santolik O, Hrbáčková Z., Pickett J. S., and Cornilleau-Wehrlin N.
Title: Equatorial noise emissions with quasiperiodic modulation of wave intensity
Abstract: Equatorial noise (EN) emissions are electromagnetic wave events at frequencies between the proton cyclotron frequency and the lower hybrid frequency observed in the equatorial region of the inner magnetosphere. They propagate nearly perpendicular to the ambient magnetic field, and they exhibit a harmonic line structure characteristic of the proton cyclotron frequency in the source region. However, they were generally believed to be continuous in time. We investigate more than 2000 EN events observed by the Spatio-Temporal Analysis of Field Fluctuations and Wide-Band Data Plasma Wave investigation instruments on board the Cluster spacecraft, and we show that this is not always the case. A clear quasiperiodic (QP) time modulation of the wave intensity is present in more than 5% of events. We. . .
Date: 04/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020816 Available at: http://doi.wiley.com/10.1002/2014JA020816
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Authors: Neal Jason J., Rodger Craig J., Clilverd Mark A., Thomson Neil R., Raita Tero, et al.
Title: Long-term determination of energetic electron precipitation into the atmosphere from AARDDVARK subionospheric VLF observations
Abstract: We analyze observations of subionospherically propagating very low frequency (VLF) radio waves to determine outer radiation belt energetic electron precipitation (EEP) flux magnitudes. The radio wave receiver in Sodankylä, Finland (Sodankylä Geophysical Observatory) observes signals from the transmitter with call sign NAA (Cutler, Maine). The receiver is part of the Antarctic-Arctic Radiation-belt Dynamic Deposition VLF Atmospheric Research Konsortia (AARDDVARK). We use a near-continuous data set spanning November 2004 until December 2013 to determine the long time period EEP variations. We determine quiet day curves over the entire period and use these to identify propagation disturbances caused by EEP. Long Wave Propagation Code radio wave propagation modeling is used to estimate the p. . .
Date: 03/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020689 Available at: http://doi.wiley.com/10.1002/2014JA020689
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Authors: Nakayama Y., Ebihara Y., Ohtani S, Gkioulidou M., Takahashi K., et al.
Title: Void structure of O + ions in the inner magnetosphere observed by the Van Allen Probes
Abstract: The Van Allen Probes Helium Oxygen Proton Electron instrument observed a new type of enhancement of O+ ions in the inner magnetosphere during substorms. As the satellite moved outward in the premidnight sector, the flux of the O+ ions with energy ~10 keV appeared first in the energy-time spectrograms. Then, the enhancement of the flux spread toward high and low energies. The enhanced flux of the O+ ions with the highest energy remained, whereas the flux of the ions with lower energy vanished near apogee, forming what we call the void structure. The structure cannot be found in the H+ spectrogram. We studied the generation mechanism of this structure by using numerical simulation. We traced the trajectories of O+ ions in the electric and magnetic fields from the global magnetohydrodynamic. . .
Date: 11/2016 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2016JA023013 Available at: http://onlinelibrary.wiley.com/doi/10.1002/2016JA023013/full
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Authors: Nakamura S., Omura Y., and Summers D.
Title: Fine structure of whistler-mode hiss in plasmaspheric plumes observed by the Van Allen Probes
Abstract: We survey 3 years (2013‐2015) of data from the Van Allen Probes related to plasmaspheric plume crossing events. We detect 194 plume crossing events, and we find that 97% of the plumes are accompanied by VLF hiss emissions. The plumes are mainly detected on the duskside or dayside. Careful examination of the hiss spectra reveals that all hiss emissions consist of obvious fine structure. Application of a band pass filter reveals that the fine structure is consistent with the occurrence of discrete wave packets. The hiss data display high coherency. The events are classified by location. Dusk side hiss and night side hiss tend to have extremely high polarization with no chorus at the high‐frequency end of the dynamic spectrum. The dusk side hiss has a distinct upper frequency limit. On th. . .
Date: 10/2018 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1029/2018JA025803 Available at: https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2018JA025803
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Authors: Nakamura Satoko, Omura Yoshiharu, Summers Danny, and Kletzing Craig A.
Title: Observational evidence of the nonlinear wave growth theory of plasmaspheric hiss
Abstract: We test the recently developed nonlinear wave growth theory of plasmaspheric hiss against discrete rising tone elements of hiss emissions observed by the Van Allen Probes. From the phase variation of the waveforms processed by bandpass filters, we calculate the instantaneous frequencies and wave amplitudes. We obtain the theoretical relation between the wave amplitude and frequency sweep rates at the observation point by applying the convective growth rates and dispersion factors to the known relation at the equator. By plotting the theoretical relation over scatterplots of the wave amplitudes and the frequency sweep rates for rising tone elements, we find good agreement between the hiss observations and the nonlinear theory. We also find that the duration periods of the hiss elements are . . .
Date: 09/2016 Publisher: Geophysical Research Letters DOI: 10.1002/2016GL070333 Available at: http://onlinelibrary.wiley.com/doi/10.1002/2016GL070333/full
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Authors: Nakamura Satoko, Omura Yoshiharu, Shoji Masafumi, Nosé Masahito, Summers Danny, et al.
Title: Sub-packet structures in EMIC rising tone emissions observed by the THEMIS probes
Abstract: We report sub-packet structures found in electromagnetic ion cyclotron (EMIC) rising tone emissions observed by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) probles. We investigate three typical cases in detail. The first case shows a continuous single rising tone with obvious four sub-packets, and the second case is characterized by a patchy emission with multiple sub-packets triggered in a broadband frequency. The third case looks like a smooth rising tone without any obvious sub-packet in the FFT spectrum, while its amplitude contains small peaks with increasing frequencies. The degree of polarization of each sub-packet is generally higher than 0.8 with a left-handed polarization, and the wave direction of the sub-packets is typically field-aligned. W. . .
Date: 08/2015 Publisher: Journal of Geophysical Research: Space Physics DOI: 10.1002/2014JA020764 Available at: http://doi.wiley.com/10.1002/2014JA020764
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Authors: Nag Sreeja, LeMoigne Jacqueline, and de Weck Olivier
Title: Cost and risk analysis of small satellite constellations for earth observation
Abstract: Distributed Space Missions (DSMs) are gaining momentum in their application to Earth science missions owing to their ability to increase observation sampling in spatial, spectral, temporal and angular dimensions. Past literature from academia and industry have proposed and evaluated many cost models for spacecraft as well as methods for quantifying risk. However, there have been few comprehensive studies quantifying the cost for multiple spacecraft, for small satellites and the cost risk for the operations phase of the project which needs to be budgeted for when designing and building efficient architectures. This paper identifies the three critical problems with the applicability of current cost and risk models to distributed small satellite missions and uses data-based modeling to sugges. . .
Date: 03/2014 Publisher: IEEE DOI: 10.1109/AERO.2014.6836396 Available at: http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=6836396
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