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Articles 1 - 30 of 176
Full-Text Articles in Entire DC Network
Low Cost Magnetometer Calibration And Distributed Simultaneous Multipoint Ionospheric Measurements From A Sounding Rocket Platform, Joshua W. Milford
Low Cost Magnetometer Calibration And Distributed Simultaneous Multipoint Ionospheric Measurements From A Sounding Rocket Platform, Joshua W. Milford
Doctoral Dissertations and Master's Theses
Low-cost and low-size-weight-and-power (SWaP) magnetometers can provide greater accessibility for distributed simultaneous measurements in the ionosphere, either onboard sounding rockets or on CubeSats. The Space and Atmospheric Instrumentation Laboratory (SAIL) at Embry-Riddle Aeronautical University has launched a multitude of sounding rockets in recent history: one night-time mid-latitude rocket from Wallops Flight Facility in August 2022 and three mid-latitude rockets from White Sands Missile Range during the October 2023 annular solar eclipse. All rockets had a comprehensive suite of instruments for electrodynamics and neutral dynamics measurements. Among this suite was one science-grade three-axis fluxgate magnetometer (Billingsley TFM65VQS / TFM100G2) and up …
Kinematics Of Fluids, Andrei Ludu
Kinematics Of Fluids, Andrei Ludu
Publications
The goal of this chapter is to discuss the general frame of hydrodynamics, like particle trajectories (path lines), streamlines, streak lines, free surfaces, and fluid surfaces, and to compare their behavior in the Eulerian and Lagrangian frames. The following sections and chapters proceed on the assumption that the fluid is practically continuous and homogeneous in structure. Of course, the concept of continuum is an abstraction that does not take into account the molecular and nuclear structure of matter. In that, we assume that the properties of the fluid do not change if we consider smaller and smaller amounts of matter …
Hydrodynamics, Andrei Ludu
Hydrodynamics, Andrei Ludu
Publications
The mathematical description of the states of a fluid is based on the study of three fields defined on the domain occupied by the fluid: the velocity field V, the density ρ, and the pressure field P. These three “unknowns” are determined by integrating other five scalar equations, namely the mass conservation (continuity equation), the three components of the equation of momentum balance (Euler or Navier–Stokes), and the energy balance. This last equation needs in addition information about the thermodynamics of the fluid, so it may need to be supplied with some equation of state. In addition to these five …
Kinetic Modeling Of Ionospheric Outflows Observed By The Visions-1 Sounding Rocket, Robert M. Albarran Ii
Kinetic Modeling Of Ionospheric Outflows Observed By The Visions-1 Sounding Rocket, Robert M. Albarran Ii
Doctoral Dissertations and Master's Theses
Plasma escape from the high-latitude ionosphere (ion outflow) serves as a significant source of heavy plasma to magnetospheric plasma sheet and ring current regions. Outflows alter mass density and reconnection rates, hence global responses of the magnetosphere. The VISIONS-1 (VISualizing Ion Outflow via Neutral atom imaging during a Substorm) sounding rocket was launched on Feb. 7, 2013 at 8:21 UTC from Poker Flat, Alaska, into an auroral substorm with the objective of identifying the drivers and dynamics of nightside ion outflow at altitudes where it is initiated, below 1000 km. Energetic ion data from the VISIONS-1 polar cap boundary crossing …
Rocket Measurements Of Electron Energy Spectra From Earth’S Photoelectron Production Layer, Aroh Barjatya, Shantanab Debchoudhury, Glyn A. Collinson, Alex Glocer, Dennis Chornay, Et Al.
Rocket Measurements Of Electron Energy Spectra From Earth’S Photoelectron Production Layer, Aroh Barjatya, Shantanab Debchoudhury, Glyn A. Collinson, Alex Glocer, Dennis Chornay, Et Al.
Publications
Photoelectrons are crucial to atmospheric physics. They heat the atmosphere, strengthen 28 planetary ambipolar electric fields, and enhance the outflow of ions to space. However, 29 there exist only a handful of measurements of their energy spectrum near the peak of 30 photoproduction. We present calibrated energy spectra of pristine photoelectrons at their 31 source by a prototype Dual Electrostatic Analyzer (DESA) instrument flown on July 11 32 2021 aboard the Dynamo-2 sounding rocket (NASA № 36.357). Photopeaks arising from 33 30.4nm He-II spectral line were observed throughout the flight above 120km. DESA also 34 successfully resolved the rarely observed …
Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa
Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa
Beyond: Undergraduate Research Journal
Radioactive sources, such as uranium-235, are nuclides that emit ionizing radiation, and which can be used to build nuclear weapons. In public areas, the presence of a radioactive nuclide can present a risk to the population, and therefore, it is imperative that threats are identified by radiological search and response teams in a timely and effective manner. In urban environments, such as densely populated cities, radioactive sources may be more difficult to detect, since background radiation produced by surrounding objects and structures (e.g., buildings, cars) can hinder the effective detection of unnatural radioactive material. This article presents a computational model …
Statistical Characteristics Of High-Frequency Gravity Waves Observed By An Airglow Imager At Andes Lidar Observatory, Alan Z. Liu, Bing Cao
Statistical Characteristics Of High-Frequency Gravity Waves Observed By An Airglow Imager At Andes Lidar Observatory, Alan Z. Liu, Bing Cao
Publications
The long-term statistical characteristics of high-frequency quasi-monochromatic gravity waves are presented using multi-year airglow images observed at Andes Lidar Observatory (ALO, 30.3° S, 70.7° W) in northern Chile. The distribution of primary gravity wave parameters including horizontal wavelength, vertical wavelength, intrinsic wave speed, and intrinsic wave period are obtained and are in the ranges of 20–30 km, 15–25 km, 50–100 m s−1, and 5–10 min, respectively. The duration of persistent gravity wave events captured by the imager approximately follows an exponential distribution with an average duration of 7–9 min. The waves tend to propagate against the local background winds and …
The Replacement Rule For Nonlinear Shallow Water Waves, A. Ludu, Z. Zong
The Replacement Rule For Nonlinear Shallow Water Waves, A. Ludu, Z. Zong
Publications
When a (1 + 1)-dimensional nonlinear PDE in real function η(x, t) admits localized traveling solutions we can consider L to be the average width of the envelope, A the average value of the amplitude of the envelope, and V the group velocity of such a solution. The replacement rule (RR or nonlinear dispersion relation) procedure is able to provide a simple qualitative relation between these three parameters, without actually solve the equation. Examples are provided from KdV, C-H and BBM equations, but the procedure appears to be almost universally valid for such (1 + 1)-dimensional nonlinear PDE and their …
Mms Observations Of The Kelvin-Helmholtz Instability And Associated Ion Scale Waves, Rachel C. Rice
Mms Observations Of The Kelvin-Helmholtz Instability And Associated Ion Scale Waves, Rachel C. Rice
Doctoral Dissertations and Master's Theses
The detailed mechanisms coupling the solar wind to Earth's magnetosphere are not yet fully understood. Solar wind plasma is heated non-adiabatically as it penetrates the magnetosphere, and this process must span scale sizes. Reconnection alone is not able to account for the observed heating; other mechanisms must be at work. One potential process is the Kelvin-Helmholtz instability (KHI). The KHI is a convective instability which operates at the fluid scale in plasmas, but is capable of driving secondary process at smaller scales. Previous work has shown evidence of magnetic reconnection, various ion scale wave modes, mode conversion, and turbulence associated …
Whistler Waves: Modeling And Observations, Daniel Williams
Whistler Waves: Modeling And Observations, Daniel Williams
Doctoral Dissertations and Master's Theses
The thesis presents the results of all the research from the published and in publication process research in the Journal of Geophysical Research [1]. This research focuses on whistler wave ducting events in the equatorial magnetosphere. High-density ducts are the main focus of whistler study in both studies as they are commonly observed by the Van Allen Probe satellites. A three-step procedure based on the analysis of the whistler wave dispersion relation and numerical simulations of the electron magnetohydrodynamics model. We use this model to identify the parallel and perpendicular wave numbers of the “most trapped” wave in an attempt …
Vertical Take-Off And Landing Control Via Dual-Quaternions And Sliding Mode, Joshua Sonderegger
Vertical Take-Off And Landing Control Via Dual-Quaternions And Sliding Mode, Joshua Sonderegger
Doctoral Dissertations and Master's Theses
The landing and reusability of space vehicles is one of the driving forces into renewed interest in space utilization. For missions to planetary surfaces, this soft landing has been most commonly accomplished with parachutes. However, in spite of their simplicity, they are susceptible to parachute drift. This parachute drift makes it very difficult to predict where the vehicle will land, especially in a dense and windy atmosphere such as Earth. Instead, recent focus has been put into developing a powered landing through gimbaled thrust. This gimbaled thrust output is dependent on robust path planning and controls algorithms. Being able to …
A Numerical Solution Of Water Flow In Unsaturated Soil With Evapotraspiration, Andrei Ludu, Harihar Khanal, Ramesh Chandra Timsina, Kedar Nath Uprety
A Numerical Solution Of Water Flow In Unsaturated Soil With Evapotraspiration, Andrei Ludu, Harihar Khanal, Ramesh Chandra Timsina, Kedar Nath Uprety
Publications
Flow movement in unsaturated soil can be expressed by Richards equation. This equation can be obtained by applying the mass conversation law and the Darcy law. In this work, we solve one-dimensional Kirchhoff transformed Richards equation with loss of water due to the evaporation of unsaturated porous media (soils) and transpiration of plants numerically using Crank-Nicolson method. The result has compared with evapotranspiration function and without it in the governing equation. It has found that an additional work in time and flow movement is needs to reach the given boundary condition for the model without evapotranspiration.
Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov
Reduced-Order Dynamic Modeling And Robust Nonlinear Control Of Fluid Flow Velocity Fields, Anu Kossery Jayaprakash, William Mackunis, Vladimir Golubev, Oksana Stalnov
Publications
A robust nonlinear control method is developed for fluid flow velocity tracking, which formally addresses the inherent challenges in practical implementation of closed-loop active flow control systems. A key challenge being addressed here is flow control design to compensate for model parameter variations that can arise from actuator perturbations. The control design is based on a detailed reduced-order model of the actuated flow dynamics, which is rigorously derived to incorporate the inherent time-varying uncertainty in the both the model parameters and the actuator dynamics. To the best of the authors’ knowledge, this is the first robust nonlinear closed-loop active flow …
Acoustic/Gravity Wave Phenomena In Wide-Field Imaging: From Data Analysis To A Modeling Framework For Observability In The Mlt Region And Beyond, Jaime Aguilar Guerrero
Acoustic/Gravity Wave Phenomena In Wide-Field Imaging: From Data Analysis To A Modeling Framework For Observability In The Mlt Region And Beyond, Jaime Aguilar Guerrero
Doctoral Dissertations and Master's Theses
Acoustic waves, gravity waves, and larger-scale tidal and planetary waves are significant drivers of the atmosphere’s dynamics and of the local and global circulation that have direct and indirect impacts on our weather and climate. Their measurements and characterization are fundamental challenges in Aeronomy that require a wide range of instrumentation with distinct operational principles. Most measurements share the common features of integrating optical emissions or effects on radio waves through deep layers of the atmosphere. The geometry of these integrations create line-of-sight effects that must be understood, described, and accounted for to properly present the measured data in traditional …
Ultra-Low Frequency Waves At Middle Latitudes During Substorms: Observations And Modeling, Mergen Alimaganbetov
Ultra-Low Frequency Waves At Middle Latitudes During Substorms: Observations And Modeling, Mergen Alimaganbetov
Doctoral Dissertations and Master's Theses
This doctoral dissertation presents the results of investigation of the Ultra-Low Frequency (ULF) waves at middle latitudes during substorms. The dissertation consists of two major parts, observations and simulations. The research in this dissertation proposes that the main role in the generation of ULF waves at middle latitudes during substorm belongs to the plasmapause.
The first part of the dissertation presents results of the data analysis of 84 intense substorm events as well as an overview of space observation programs such as CRRES, Van Allen Probes and DMSP. Data used in this study are from the ACE satellite taken measurements …
Nonlinear Schrödinger Equation Solitons On Quantum Droplets, A. Ludu, A.S. Carstea
Nonlinear Schrödinger Equation Solitons On Quantum Droplets, A. Ludu, A.S. Carstea
Publications
Irrotational flow of a spherical thin liquid layer surrounding a rigid core is described using the defocusing nonlinear Schrödinger equation. Accordingly, azimuthal moving nonlinear waves are modeled by periodic dark solitons expressed by elliptic functions. In the quantum regime the algebraic Bethe ansatz is used in order to capture the energy levels of such motions, which we expect to be relevant for the dynamics of the nuclear clusters in deformed heavy nuclei surface modeled by quantum liquid drops. In order to validate the model we match our theoretical energy spectra with experimental results on energy, angular momentum, and parity for …
Investigation Of Trajectory And Control Designs For A Solar Sail To The Moon, Michelle Nadeau
Investigation Of Trajectory And Control Designs For A Solar Sail To The Moon, Michelle Nadeau
Doctoral Dissertations and Master's Theses
NASA’s Artemis program and other government and commercial projects are working toward establishing a sustainable human presence on the moon. This thesis investigates the technical feasibility of a solar sail-based spacecraft (sailcraft) as a low-cost method of delivering cargo or science instruments to the moon and demonstrates how this sailcraft could be controlled to change its orbit. The concept is a low-cost, commercial launch vehicle-deployable, CubeSat-based sailcraft with a square sail, assumed attitude control, and a small payload traversing from low-Earth orbit toward the moon with zero propellant use. In this thesis, methods for sailcraft to increase altitude, the trajectory …
Proton Aurora At Mars: Assessing The Characteristics, Variability, And Driving Mechanisms Of A Newly Discovered Phenomenon, Andréa C.G. Hughes
Proton Aurora At Mars: Assessing The Characteristics, Variability, And Driving Mechanisms Of A Newly Discovered Phenomenon, Andréa C.G. Hughes
Doctoral Dissertations and Master's Theses
The purpose of this doctoral research dissertation is to develop a deeper understanding of the phenomenology, variability and driving processes of proton aurora at Mars. Proton aurora are the most recently discovered of the three types of Martian aurora. Due to Mars’ lack of a global dipole magnetic field, the formation processes of Martian proton aurora are uniquely different than aurora on Earth. Martian proton aurora are expected to form on the planet’s dayside via electron stripping/charge exchange processes between solar wind protons and the neutral hydrogen corona. Herein, I present the results of a study of proton aurora at …
Potential Applications Of Electrodynamic Tethers, Sai Charan Petchetti
Potential Applications Of Electrodynamic Tethers, Sai Charan Petchetti
International Journal of Aviation, Aeronautics, and Aerospace
In recent decades, alternative propulsion systems have been investigated and have attracted great interest in the space community. Most of these alternative propulsion systems need propellants. One alternative propulsion system that does not require propellants and is not often discussed is electrodynamic tethers (EDTs). This paper speculates the potential applications of EDTs ranging from radiation belt remediation to momentum exchange tether re-boosting.
Setting Constraints On The Lunar Exosphere: A Comprehensive Analysis Of Velocity Resolved Sodium And Potassium Line Profile Measurements, Dona Chathuni P. Kuruppuaratchi
Setting Constraints On The Lunar Exosphere: A Comprehensive Analysis Of Velocity Resolved Sodium And Potassium Line Profile Measurements, Dona Chathuni P. Kuruppuaratchi
Doctoral Dissertations and Master's Theses
This dissertation outlines and presents the most comprehensive set of velocity-resolved measurements of sodium D2 (5889.9509 Å) lines taken over multiple lunations spanning seven years (2011 – 2017). These data are used to study the morphology and dynamics of the lunar exosphere. Additionally, potassium D1 (7698.9646 Å) is used as a complement to sodium. The two species approach, with sodium being the main attraction, provides constraints on the critical drivers of the lunar exosphere. Observations were made at the National Solar Observatory McMath – Pierce Telescope, Kitt Peak, Arizona where I personally collected both sodium and potassium data over about …
Finite-Time State Estimation For An Inverted Pendulum Under Input-Multiplicative Uncertainty, Sergey V. Drakunov, William Mackunis, Anu Kossery Jayaprakash, Krishna Bhavithavya Kidambi, Mahmut Reyhanoglu
Finite-Time State Estimation For An Inverted Pendulum Under Input-Multiplicative Uncertainty, Sergey V. Drakunov, William Mackunis, Anu Kossery Jayaprakash, Krishna Bhavithavya Kidambi, Mahmut Reyhanoglu
Publications
A sliding mode observer is presented, which is rigorously proven to achieve finite-time state estimation of a dual-parallel underactuated (i.e., single-input multi-output) cart inverted pendulum system in the presence of parametric uncertainty. A salient feature of the proposed sliding mode observer design is that a rigorous analysis is provided, which proves finite-time estimation of the complete system state in the presence of input-multiplicative parametric uncertainty. The performance of the proposed observer design is demonstrated through numerical case studies using both sliding mode control (SMC)- and linear quadratic regulator (LQR)-based closed-loop control systems. The main contribution presented here is the rigorous …
Experimental Study Of Breathers And Rogue Waves Generated By Random Waves Over Non-Uniform Bathymetry, A. Ludu, A. Wang, Z. Zong, L. Zou, Y. Pei
Experimental Study Of Breathers And Rogue Waves Generated By Random Waves Over Non-Uniform Bathymetry, A. Ludu, A. Wang, Z. Zong, L. Zou, Y. Pei
Publications
We present experimental evidence of formation and persistence of localized waves, breathers, and solitons, occurring in a random sea state and uniformly traveling over non-uniform bathymetry. Recent studies suggest connections between breather dynamics and irregular sea states and between extreme wave formation and breathers, random sea states, or non-uniform bathymetry individually. In this paper, we investigate the joint connection between these phenomena, and we found that breathers and deep-water solitons can persist in more complex environments. Three different sets of significant heights have been generated within a Joint North Sea Wave Observation Project wave spectrum, and the wave heights were …
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer
Publications
In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …
Coherent Captain Mills: The Search For Sterile Neutrinos, Ashley Elliott, Jeramy Gordon, Jonah Greenwood, Rachel Lake, Ryder Moreno, Emily Strawn, Kate Walker
Coherent Captain Mills: The Search For Sterile Neutrinos, Ashley Elliott, Jeramy Gordon, Jonah Greenwood, Rachel Lake, Ryder Moreno, Emily Strawn, Kate Walker
Discovery Day - Prescott
The observation of neutrino oscillations confirms that the active neutrinos (νe, νμ, ντ) are comprised of three mass eigenstates with Δm2 values between 10-3 to 10-5 eV2 . However, a persistent phenomenon has been observed at LSND, MiniBooNE and other shortbaseline experiments (SBE) where Δm2 ~ 1eV2 and is not compatible with the current mixing between mass eigenstates. However, a 4th neutrino, a sterile neutrino (νs) that doesn’t participate in weak interactions could explain the phenomena observed as SBE’s. An experiment has been constructed at TA-53 at Los Alamos National Laboratory to investigate this large Δm2 ~ 1eV2 and determine …
Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen
Studies Of Oval Tube And Fin Heat Exchangers, Phillip Nielsen
Discovery Day - Prescott
Heating Ventilation and air-conditioning (HVAC) is a system which changes the temperature of the surroundings for the purposes of cooling or heating. This system requires energy to maintain a temperature difference from the outside temperature. This is important since minimized power is one of the requirements for the system to achieve a better efficiency. Optimizing the flow over the evaporator coils is one way to increase the cooling efficiency. This will reduce the power required to have a sustainable system. Optimizing the flow to increase the energy transfer between the fins and the incoming air could result in a greater …
An Analysis Of The Atmospheric Propagation Of Underground-Explosion-Generated Infrasonic Waves Based On The Equations Of Fluid Dynamics: Ground Recordings, Roberto Sabatini, Jonathan B. Snively, Michael P. Hickey, J. L. Garrison
An Analysis Of The Atmospheric Propagation Of Underground-Explosion-Generated Infrasonic Waves Based On The Equations Of Fluid Dynamics: Ground Recordings, Roberto Sabatini, Jonathan B. Snively, Michael P. Hickey, J. L. Garrison
Publications
An investigation on the propagation of underground-explosion-generated infrasonic waves is carried out via numerical simulations of the equations of fluid dynamics. More specifically, the continuity, momentum, and energy conservation equations are solved along with the Herzfeld-Rice equations in order to take into account the effects of vibrational relaxation phenomena. The radiation of acoustic energy by the ground motion caused by underground explosions is initiated by enforcing the equality, at ground level, between the component of the air velocity normal to the Earth's surface and the normal velocity of the ground layer. The velocity of the ground layer is defined semi-empirically …
Non-Linear Magnetosphere-Ionosphere Interactions At High Latitudes, Beket Tulegenov
Non-Linear Magnetosphere-Ionosphere Interactions At High Latitudes, Beket Tulegenov
Doctoral Dissertations and Master's Theses
Non-linear, 3D electromagnetic coupling between the ionosphere and magnetosphere is investigated in this dissertation. The study is based on a non-linear, 3D, reduced magnetohydrodynamic model describing interaction between dispersive Alfven waves and the nightside high-latitude ionosphere. Results are presented from a numerical study of small-scale, intense magnetic field-aligned currents observed in the vicinity of the discrete auroral arc by the Magnetosphere-Ionosphere Coupling in the Alfven Resonator (MICA) sounding rocket launched from Poker Flat, Alaska, on 19 February 2012. The goal of the MICA project was to investigate the hypothesis that such currents can be produced inside the ionospheric Alfven resonator …
Ice Spiral Patterns On The Ocean Surface, Andrei Ludu, Zhi Zong
Ice Spiral Patterns On The Ocean Surface, Andrei Ludu, Zhi Zong
Publications
We investigate a new two-dimensional compressible Navier-Stokes hydrodynamic model design to explain and study large scale ice swirls formation at the surface of the ocean. The linearized model generates a basis of Bessel solutions from where various types of spiral patterns can be generated and their evolution and stability in time analyzed. By restricting the nonlinear system of equations to its quadratic terms we obtain swirl solutions emphasizing logarithmic spiral geometry. The resulting solutions are analyzed and validated using three mathematical approaches: one predicting the formation of patterns as Townes solitary modes, another approach mapping the nonlinear system into a …
Meshless Modeling Of Flow Dispersion And Progressive Piping In Poroelastic Levees, Anthony Khoury, Eduardo Divo, Alain J. Kassab, Sai Kakuturu, Lakshmi Reddi
Meshless Modeling Of Flow Dispersion And Progressive Piping In Poroelastic Levees, Anthony Khoury, Eduardo Divo, Alain J. Kassab, Sai Kakuturu, Lakshmi Reddi
Publications
Performance data on earth dams and levees continue to indicate that piping is one of the major causes of failure. Current criteria for prevention of piping in earth dams and levees have remained largely empirical. This paper aims at developing a mechanistic understanding of the conditions necessary to prevent piping and to enhance the likelihood of self-healing of cracks in levees subjected to hydrodynamic loading from astronomical and meteorological (including hurricane storm surge-induced) forces. Systematic experimental investigations are performed to evaluate erosion in finite-length cracks as a result of transient hydrodynamic loading. Here, a novel application of the localized collocation …
Planar Ion Probe For Low-Latitude Ionosphere/Thermosphere Enhancements In Density Cubesat Mission, Liam Owen Gunter
Planar Ion Probe For Low-Latitude Ionosphere/Thermosphere Enhancements In Density Cubesat Mission, Liam Owen Gunter
Doctoral Dissertations and Master's Theses
One of the crucial measurements for characterizing any space weather event is absolute plasma density and plasma density fluctuations, both spatially and temporally. Langmuir probes are the oldest and most proven instruments for these in-situ measurements. This thesis enumerates the development of a miniaturized low-noise Langmuir probe intended for a dual CubeSat mission to study equatorial temperature and wind anomaly in the Earth’s ionosphere.
The Langmuir probe instrument developed is of a planar geometry and fix biased in the ion saturation region, i.e. negative w.r.t. spacecraft chassis. Operating the Langmuir probe in the ion saturation region avoids excessive spacecraft charging …