11-20 of 27 results
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Measuring Interstellar Temperature and Ionization Variations Using Observations of Faint Diffuse [OII] Emission
PI Edwin Mierkiewicz
The interstellar medium (ISM) plays a vital role in the ongoing cycle of stellar birth and death as well as galactic evolution. However the role of interstellar matter, from how its properties are influenced by stars to how, in turn, its properties influence star formation is poorly understood.
Within the past decade substantial strides have been made towards unraveling the mysteries of a major ISM component, the widespread warm ionized medium (WIM). The advances were enabled by innovative spectroscopic techniques to detect and study extremely faint interstellar emission lines in the visible spectral region. With such observations it is possible to explore the connection between the Galactic disk and halo as energy and gas are transferred away from massive star-forming regions to large distances from the midplane. An especially exciting development in this area is the evidence for temperature variations and the existence of a previously unrecognized source of heating within the WIM. The emission line of ionized oxygen in the near ultraviolet spectral region (372.7 nm) is key to exploring variations in temperature and ionization state within the gas, and for investigating the role of this additional heating. Our [OII] observations will (1) provide the only opportunity to separate unambiguously variations in temperature from variations in ionization conditions in the warm ionized medium of our Galaxy and (2) confirm whether H-alpha, [NII], and [SII] data can provide reliable temperature information about diffuse ionized gas in our own and other galaxies.Categories: Faculty-Staff
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High Spectral Resolution Observations of Lunar Exospheric Emissions
PI Edwin Mierkiewicz
We are employing high-resolution Fabry-Perot spectroscopy of neutral sodium and potassium emission to investigate the morphology and dynamics of the lunar sodium exosphere. Likely atmosphere source mechanisms are thermal desorption, photo-desorption, ion sputtering, and meteoric impact ablation.
Their relative importance remains uncertain, both with regard to spatial and to temporal trends. Once released, sputtered gases in the lunar atmosphere can be pulled back to the regolith by gravity, escape to space, get pushed away by solar radiation pressure, or become photoionized and swept away by the solar wind. To test hypotheses about the sources, sinks, and escape of the lunar atmosphere, velocity-resolved observations under different lunar phases, altitudes, latitudes, and time histories are being made to help understand factors that link resultant morphologies to sources and solar radiation effects. These observations will help constrain atmospheric and surface-process modeling, and help quantify the source and escape mechanisms.
Categories: Faculty-Staff
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Critical Fora Discussing U.S.-Japan Space Security Cooperation
PI Elisabeth Murray
The proposed project aims to bring together leading American and Japanese space security experts with students and faculty from Embry Riddle Aeronautical University (ERAU) for a dialogue on the current state of space security and the potential for cooperation between Japan and the United States.
At the core of this project are two central goals. The first is the creation of an undergraduate-level course on U.S.-Japan Space Security Cooperation, which will be developed as part of the Security Studies and International Affairs (SSIA) Department’s Spring 2026 offerings at ERAU, a leading institution in aviation and aerospace; the second is to provide heightened public engagement between residents of the Space Coast and leading policy and academic practitioners in the field of U.S.-Japan space security.
To meet these goals, eight (8) space security experts from Japan and the U.S. will be invited to deliver a public lectures, providing both students, whose attendance will be required, faculty, and the larger public in and around the Space Coast with a unique opportunity to engage directly with leaders in the field, fostering an exchange of ideas that bridges theoretical knowledge with real-world perspectives. Through this dialogue, the project seeks to inspire students aspiring to pursue security-related careers in government policy and space industry advancement.
The project explores key questions in U.S.-Japan space security cooperation, such as: How can both nations enhance collaboration to address shared security challenges in space? What strategic and policy gaps exist, and how can these gaps be bridged to strengthen bilateral cooperation? Through these and other discussions, ERAU students and lecture attendees will gain insights into the complex dynamics of space security, and the challenges and opportunities inherent in U.S.-Japan cooperation in the space domain.
The proposed project thus has the following objectives:
1) Educational Outreach: The course and public lectures will deepen understanding of U.S.-Japan Space Security Cooperation and expose the audience to leading scholars and practitioners in this field; impact will be furthered through the creation of a sharable course dossier, a special issue journal written by undergraduate students, and the development of a grant proposal funding a topic-focused workshop in 2027.
2) Promoting Dialogue: The project will encourage the exchange of ideas between leading experts and the next generation of security professionals and industry leaders;
3) Fostering Next-Generation Solutions: The project aims to inspire innovative thinking on a global issue of mutual importance in the next generation of military and civilian policymakers and practitioners.Categories: Faculty-Staff
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The US Military and Genocide: Perpetration, Liberation, Witness, and Prevention
PI Elisabeth Murray
This program aims to facilitate a stronger relationship between veteran and ROTC students through the creation of a training and discussion program using the lens of the US military and genocide.
There are two key goals we seek to achieve through the completion of this program. The primary goal is to serve veterans through discussions of key humanities texts in genocide studies. The second goal is to bridge the ROTC and veteran communities and help prepare the next generation of military officers. There are few places where veterans can discuss the history of the US military’s relationship with genocide and help put their experience into a framework for understanding the future role of the US military in genocide prevention. To provide such a framework, this project will provide training and discussion opportunities on different cases of genocide which have been directly influenced by the US military. We will look at four different themes in relation to four different case studies:
1. US military perpetrating genocide (specifically against the Seminole in Florida);
2. US military liberating genocide (Holocaust, specifically the liberation of camps);
3. US military witnessing genocide (specifically the Yazidis and others fighting ISIS);
4. US military preventing genocide (the future of Afghanistan).
We understand the humanities as key to fostering an environment free from judgement, blame, or self-recrimination. We also understand that while it is key for both our leaders and our discussion participants to understand facts about the military’s involvement in these cases, using humanities helps negotiate the often under-acknowledged emotions of fear, rage, sorrow, pain, and sometimes other and even opposite emotions such as love, hope, and joy present within the human landscape of genocidal aggression.
We believe that a program of this nature firstly identifies a narrative and on-going relationship between the US military and the processes and consequences of genocidal violence. Considering especially the increasing challenges posed by climate change, the ongoing conflict in Eastern Europe, and increased tensions in the South China Sea, providing a space for veterans to explore this narrative will also help prepare them to understand future conflicts. However, this project goes beyond the creation of a discussion space for veterans. As discussed further below, Embry-Riddle (ERAU) has a large veteran community. ERAU also hosts one of the largest ROTC programs in the state of Florida consisting of students at three universities in Volusia County. However, there are few opportunities for these two communities to learn from each other. We believe providing an opportunity to bridge these communities will inevitably result in a stronger, more capable ROTC cadre and will provide leadership opportunities within our veteran population, adding to their skillset and knowledge transfer capabilities. The second goal of this project is to support a series of opportunities for these two communities to come together, using humanities sources as a framework for discussion. We will achieve this through the training of eight veteran discussion leaders, who will go on to lead a course under the direction of faculty offered in Fall 2023, US Military and Genocide, open to all students but targeting those in ROTC and, in Spring 2024, a series of three public discussions held at participating universities.
We believe the creation of a university course and a public discussion series on the US Military and Genocide will bring ROTC and veteran students together through deepening their understanding of the contribution of the humanities to war studies; we hope to use the community of studentship to help bridge the divide between different military “generations”. This would then continue into the facilitation of public discussions that will allow for the leadership skills gained by veterans in the classroom to be demonstrated on a larger scale and to a wider audience. Finally, we believe that both the course and discussion series will contribute to the repositioning of humanities resources into core teaching in genocide studies. While widely regarded as critical to reconstruction and reconciliation (Skavdahl 2020), humanities resources such as music and poetry are largely under-used in syllabi on genocide courses, particularly in cases other than the Holocaust (Schneider 2014). We believe exposing veterans and ROTC students to humanities sources provides a deeper understanding of mass violence than an historical study alone can convey. In genocide studies, it is easy to get lost in the numbers; 1 million dead, 500,000 dead, 6 million Jews, 13 million victims – these numbers are hard for the mind to understand and often mask the impact of each individual loss. Music, poetry, art, and oral history are not only at the center of the humanities but are at the heart of humanity; they give voice to the cultural structure of identity. Genocide is legally defined as the intentional destruction "in whole or in part a national, ethnical, racial or religious group”. The destruction of culturally defined humanities artifacts are integral to the destruction of that group identity. By highlighting the value of these works in understanding the US Military’s relationship with genocide, we hope to reposition the value of the individual and to give our veterans and rising military leaders a chance to better understand their place within this relationship.Categories: Faculty-Staff
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Collaborative Research: Wideband Multi-Beam Antenna Arrays: Low-Complexity Algorithms and Analog-CMOS Implementations
PI Sirani Mututhanthrige Perera
PI Arjuna Habarakada Madanayake
PI Soumyajit Mandal
Explosion of millimeter-wave (mm-wave) bandwidth opens up applications in 5G wireless systems spanning communications, localization, imaging, and radar. This project addresses challenges in mathematics, engineering, and science in developing efficient wideband beamformers based on sparse factorizations of the matrix called-delay Vandermonde matrices (DVM). The proposed highly integrated approach is attractive for mobile applications including 5G smart devices, the internet of things, mobile robotics, unmanned aerial vehicles, and other emerging applications focused on mm-waves.
A multi-beam array receiver is deeply difficult to realize in integrated circuit (IC) form due to the underlying complexity of its signal flow graph. Through the proposed work, mathematical methods based on the theories of i) sparse factorization and complexity of the structured complex DVM with the introduction of a super class for the discrete Fourier transform(which is DVM), and ii) approximation transforms are proved to solve this problem.
The resulting matrices are realized with multi-GHz bandwidths using analog ICs. The novel DVM algorithm solves the longstanding "beam squint" problem, i.e., the fact that the beam direction changes with input frequency, making true wideband operation impossible. Moreover, the proposed multi-beamforming networks in analog IC form will be realized efficiently while addressing precision circuit design, digital calibration, built-in self-test, etc. Besides scientific merits, both minority students and female students will be mentored to pursue careers in the STEM disciplines through the proposed project.
This project was funded by the National Science Foundation (the division of Electrical, Communications, and Cyber Systems) with award numbers 1711625 and 1711395.
Categories: Faculty-Staff
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Cross-Scale Wave Coupling Processes in Kelvin-Helmholtz Structures
PI Heidi Nykyri
Project investigates cross-scale wave coupling processes and their role on ion heating, mixing and diffusion.
One of the pending problems in collisionless plasmas is to understand the plasma heating and transport across three fundamental scales: fluid, ion and electron. The plasma inside Earth’s magnetotail plasma sheet is ~50 times hotter than in the magnetosheath. Furthermore, the specific entropy increases by two orders of magnitude from the magnetosheath to the magnetosphere, which is a signature of a strong non-adiabatic heating. Also, the cold component ions are hotter by ~30 % at the dawnside compared to those measured on the duskside. Our recent statistical study using THEMIS data indicates that the magnetosheath seed population is not responsible for this asymmetry so additional physical mechanisms at the magnetopause or plasma sheet must be at work to explain this asymmetric heating. Recent works suggest that dawn-flank magnetopause boundary is more prone to the fluid-scale Kelvin-Helmholtz instability (KHI) as well as to the ion-scale electromagnetic wave activity, which may help explain the observed plasma sheet asymmetry. Project uses numerical simulations, plasma theory and spacecraft observations to understand relation of small-scale waves to large-scale velocity driven modes and evaluate their role in mixing, diffusion, and heating of ions.
Categories: Faculty-Staff
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Experimental Identification of Plasma Wave Modes in Vicinity of KH Vortices and in Plasma ’Mixing’ Regions in Low Latitude Boundary Layer (Ion scales)
PI Heidi Nykyri
Project uses Cluster spacecraft data to identify ion-scale waves within Kelvin-Helmholtz waves.
Project uses Cluster spacecraft data to identify ion-scale waves within Kelvin-Helmholtz waves.Categories: Faculty-Staff
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Statistical correlation study between solar wind, magnetosheath and plasma sheet properties
PI Heidi Nykyri
CO-I Xuanye Ma
Statistical study of the solar wind, magnetosheath, and magnetospheric plasma properties usinng 8+ years of THEMIS data.
The study will utilize recently developed statistical tool developed under Nykyri's NSF CAREER grant to present 8+ years of THEMIS spacecraft data in the coordinate system that takes into account the motion of the magnetopause and bow shock and will organize THEMIS observations into spatial bins with respect to physical boundaries under prevailing solar wind conditions. The study will address how do the plasma sheet properties such as number density, temperature, electron to ion temperature ratio and specific entropy vary during a) Parker-Spiral, Ortho-parker spiral, Northward and Southward IMF, and b) during high and slow solar wind speed, and how are these correlated with corresponding magnetosheath properties?
Categories: Faculty-Staff
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NSF Career Award: Effects of Magnetosheath properties on the dynamics and plasma transport produced by the Kelvin-Helmholtz Instability and on the Plasma Sheet Anisotropies
PI Heidi Nykyri
Project investigates impact of magnetosheath properties on Kelvin-Helmholtz instability
The magnetosheath processes will be studied by doing a statistical study of the magnetosheath properties using THEMIS data and by utilizing global hybrid (fluid electrons, particle ions) simulations. In addition, the MHD-scale KHI will be compared with hybrid and particle simulations of the instability.
Categories: Faculty-Staff
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Turbulence and Structure in the Magnetospheric Cusps: Cluster spacecraft observations
PI Heidi Nykyri
Project analyzes the structure, origin of fluctuations and high-energy particles in the high-altitude cusp regions
Project uses Cluster data and high-resolution local 3-D MHD simulations with test particles to determine the structure and origin of high-energy particles in the high-altitude cuspCategories: Faculty-Staff
11-20 of 27 results