A5022722350- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Earthquake Detection and Analysis
- Plasma Diagnostics and Applications
- Astro and Planetary Science
- Magnetic Field Sensors Techniques
- Laser-induced spectroscopy and plasma
- Magnetic confinement fusion research
- Geophysics and Gravity Measurements
- Photocathodes and Microchannel Plates
- Nuclear Physics and Applications
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Geophysics and Sensor Technology
- Metal and Thin Film Mechanics
- Spacecraft and Cryogenic Technologies
- Electrohydrodynamics and Fluid Dynamics
- Electromagnetic Launch and Propulsion Technology
- Effects of Vibration on Health
- Advanced Data Storage Technologies
- Characterization and Applications of Magnetic Nanoparticles
- Big Data Technologies and Applications
- Particle accelerators and beam dynamics
Goddard Space Flight Center
2015-2024
University of Guelph
2024
Four Directions Development Corporation
2018-2021
Aurora Optics (United States)
2017-2019
University of Colorado Boulder
2016-2018
Millennium Engineering and Integration (United States)
2010-2016
Stinger Ghaffarian Technologies (United States)
2011-2015
Heliophysics
2012
Heliophysics Science Division
2012
MEI Technologies (United States)
2011
The Fast Plasma Investigation (FPI) was developed for flight on the Magnetospheric Multiscale (MMS) mission to measure differential directional flux of magnetospheric electrons and ions with unprecedented time resolution resolve kinetic-scale plasma dynamics. This increased has been accomplished by placing four dual 180-degree top hat spectrometers around periphery each MMS spacecraft. Using electrostatic field-of-view deflection, eight species together provide 4pi-sr with, at worst,...
Abstract Based on high‐resolution measurements from NASA's Magnetospheric Multiscale mission, we present the dynamics of electrons associated with current systems observed near diffusion region magnetic reconnection at Earth's magnetopause. Using pitch angle distributions (PAD) and curvature analysis, demonstrate occurrence electron scattering in curved field down to energies 20 eV. We show that occurs closer sheet as energy decreases. The inflowing electrons, field‐aligned electrostatic...
Abstract Magnetic holes are ubiquitous in space plasmas, occurring the solar wind, downstream of planetary bow shocks, and inside magnetosphere. Recently, kinetic‐scale magnetic have been observed near Earth's central plasma sheet. The Fast Plasma Investigation on NASA's Magnetospheric Multiscale (MMS) mission enables measurement both ions electrons with 2 orders magnitude increased temporal resolution over previous magnetospheric instruments. Here we present data from MMS taken nightside...
Abstract Secondary electrons are continuously generated via photoemission from sunlit spacecraft and instrument surfaces. These particles can subsequently contaminate low‐energy channels of electron sensors. Spacecraft photoelectrons measured at energies below that a positive potential be removed the expense energy resolution. However, fluxes inside instruments independent must fully characterized in order to correct data. Here we present observations photoelectron populations with Dual...
The Modular Spectrometer for Atmosphere and Ionosphere Characterization (MoSAIC) is a quadrupole mass spectrometer (QMS), which will fly on NASA's Geospace Dynamics Constellation (GDC) mission in low Earth orbit, providing measurements of neutral ionized gas density, temperature, composition, wind/drift. MoSAIC includes Baffle Scanning Mechanism (BSM), periodically sweeps front the QMS aperture, enabling determination ion temperature cross-track velocity. Accurate knowledge plasma wake...
We report our findings comparing the geometric factor (\documentclass[12pt]{minimal}\begin{document}$\mathbb {GF}$\end{document}GF) as determined from simulations and laboratory measurements of new Dual Electron Spectrometer (DES) being developed at NASA Goddard Space Flight Center part Fast Plasma Investigation on NASA’s Magnetospheric Multiscale mission. Particle are increasingly playing an essential role in design calibration electrostatic analyzers, facilitating identification mitigation...
Abstract Systematic uncertainties in the conversion of measured counts to phase space density by charged particle instrumentation result errors reported plasma moments (e.g., density, velocity, and temperature). Unlike previous that relied on a spacecraft spin sample all look‐directions, Fast Plasma Investigation (FPI) suite NASA's Magnetospheric Multiscale mission nearly simultaneously images full sky. This configuration results unprecedented time resolution but also introduces possibility...
Abstract Cold plasma (up to few tens of electron volts) ionospheric origin is present most the time, in regions Earth's magnetosphere. However, characterizing it using situ measurements difficult, owing spacecraft electrostatic charging, as often this charging at levels comparable or even higher than equivalent energy cold plasma. To overcome difficulty, active potential control devices are usually placed on that artificially reduce charging. The structure around assumed be spherically...
Abstract Electromagnetic whistler-mode waves in space plasmas play critical roles collisionless energy transfer between the electrons and electromagnetic field. Although resonant interactions have been considered as likely generation process of waves, observational identification has extremely difficult due to short time scale electron dynamics. Here we show strong nongyrotropy, which rotate with wave, cyclotron direct evidence for locally ongoing secular from using ultra-high temporal...
As spacecraft does not have an independent method to conduct charge ground, it naturally accumulates due interactions with the ambient plasma and surface emission. This produces electric field surrounding spacecraft, which takes form of a sheath. Charged particles traveling through this sheath are altered in both energy direction, thus affecting derived scientific quantities. While effect has been known since advent space based particle instruments, work represents first time that situ...
Abstract Data compression has been a staple of imaging instruments for years. Recently, plasma measurements have utilized with relatively low ratios. The Fast Plasma Investigation (FPI) on board the Magnetospheric Multiscale (MMS) mission generates data roughly 100 times faster than previous instruments, requiring higher ratio to fit within telemetry allocation. This study investigates performance space‐based standard employing Discrete Wavelet Transform and Bit Plane Encoder (DWT/BPE) in...
The Fast Plasma Investigation (Pollock et al., , https://doi.org/10.1007/s11214-016-0245-4 ; FPI) onboard the Magnetospheric Multiscale mission (Burch, Moore, https://doi.org/10.1007/s11214-015-0164-9 MMS) uses a discrete wavelet transform and bit plane encoder (DWT/BPE; Winterrowd https://doi.org/10.1109/AERO.2010.5446664 ) for data compression. This is first plasma spectrometer suite to use this method of compression thus serves as benchmark future spectrometers. Flight from MMS confirm...
Abstract The most common instrument for low‐energy plasmas consists of a top‐hat electrostatic analyzer (ESA) geometry coupled with microchannel‐plate‐based (MCP‐based) detection system. While the optics such sensors are readily simulated and parameterized during laboratory calibration process, system is often less well characterized. Here we develop comprehensive mathematical description particle systems. As function azimuthal angle, parameterize (1) scattering within ESA at surface MCP,...
A plasma spectrometer design based on advances in lithography and microchip stacking technologies is described. series of curved plate energy analyzers, with an integrated collimator, etched into a silicon wafer. Tests elements, the analyzer were performed 5 keV electron beam. The measured collimator transmission selectivity good agreement targets. single wafer element could be used as processing or fusion first wall diagnostic.
NASA's Magnetospheric MultiScale (MMS) is an unmanned constellation of four identical spacecraft designed to investigate magnetic reconnection by obtaining detailed measurements plasma properties in Earth's magnetopause and magnetotail. Each the satellites carries a suite instruments which characterize ambient ion electron energy spectrum composition. Some these utilize high-voltage microchannel plates are sensitive particulate contamination. In this paper, we analyze transport particulates...
Abstract Taking advantage of technological developments in wafer‐scale processing over the past two decades, such as deep etching, 3‐D chip stacking, and double‐sided lithography, we have designed fabricated key elements an ultracompact (1.5 cm) 3 plasma spectrometer that requires only low‐voltage power supplies, has no microchannel plates, a high aperture area to instrument volume ratio. The initial design targets measurement charged particles 3–20 keV range with highly directional field...
The Fast Plasma Investigation onboard the Magnetospheric Multiscale (MMS) mission captures full‐sky particle data over a range of 10 eV to 30 keV every ms for electrons and 150 ions. Only about 5% count at this time resolution are sent ground due telemetry limitations; however, complete set trigger terms their small volume. These composed simplified integrals that scale proportionally plasma moments. They were initially conceived as mechanism rank scientific priority downlink; they can be...
The Fast Plasma Investigation (FPI) is an instrument suite aboard NASA's Magnetospheric Multiscale space physics mission, which designed to study magnetic reconnection in the Earth's magnetosphere. In this work, a predictive model of microchannel plate (MCP) current was developed for FPI autonomously monitor device currents. results analysis resistance plates included particle spectrometers are presented along with new that combines physically-informed MCP empirically-derived temperature....
Off-road mobile machine operators are exposed to whole-body vibration (WBV) which can result in adverse health effects. Seat suspensions used reduce WBV exposure, but typical passive seats cannot attenuate frequencies below 1.13 Hz. The proposed device is designed minimize transmissibility from 0 20 Hz because this bandwidth contains the dominant frequency for most off-road vehicles. semi-active smart uses bang-bang control and be installed place of seat-pan cushion OEM seats. Modelled as a...
During the September 2015 to March 2016 duration (sometimes referred as Phase 1A) of Magnetospheric Multiscale Mission, Dual Electron Spectrometers (DES) were configured generously utilize lossy compression. While this maximized number velocity distribution functions downlinked, it came at expense lost information content for a fraction frames. Following period compression, DES was reconfigured in way that allowed 95% frames arrive ground without loss. Using high-quality set from on-orbit...