Physics Commons^™

In Situ Observations Of Thermal Ions In Perturbed Ionospheres: Techniques And Results, Magdalina Louise Moses

Dartmouth College Ph.D Dissertations

Prediction and mitigation of space weather events are active research topics that require knowledge of the physics governing the ionosphere. Sounding rockets can be used to make in situ observations. The Lynch Rocket Lab created the Petite-Ion-Probe (PIP), a small retarding potential analyzer, to measure thermal ion parameters (i.e., ion density and temperature). A PIP's raw data consists of a series of measured anode currents as a function of screen bias voltages, called IV curves. PIPs can be integrated onto a sounding rocket’s main payload and/or be deployed from the rocket on small platforms called ``PIP-Bobs''. Note that as the …

Geometry Of Almost-Conserved Quantities In Symplectic Maps: Approximate Invariants In Nonlinear Accelerator Systems, T. Zolkin, S. Nagaitsev, I. Morozov, S. Kladov

Physics Faculty Publications

We present a perturbative method for constructing approximate invariants of motion directly from the equations of discrete-time symplectic systems. This framework offers a natural nonlinear extension of the classic Courant-Snyder (CS) theory for systems with 1 degree of freedom—a foundational cornerstone in accelerator physics now spanning seven decades and historically focused on linear phenomena. The original CS formalism emerged under conditions where nonlinearities were weak, design goals favored linear motion, and analytical tools—such as the Kolmogorov-Arnold-Moser theory—had not yet been fully developed. While various normal-form methods have been proposed to treat near-integrable dynamics, the approach introduced here stands out for …

Utilizing Computer Modeling To Optimize Electric Fields Within Xenon Time Projection Chambers, Miles Meloni

Honors Theses

XENONnT is a physics experiment designed with the goal of detecting dark matter particles. The detector is a time projection chamber; a series of charged electrodes creates an electric field, surrounding a central body filled with liquid and gaseous xenon. Photomultiplier tubes (PMTs), positioned on either end of the chamber, serve to detect light signals. We seek to minimize the root mean square of the electric field norms experienced by the PMTs. This quantity corresponds to the variance in the electric field observed by the PMTs. Establishing a consistent electric field is important to maintaining these sensitive components. The electric …

Ai-Enabled Digital Twins And Optimization Workflows For Accelerator Control, M. Yadav, A. Seryi, B. Terzic, J. Bird, J. Delayen, K. Makino, K. Ahmed, L. Van Riesen-Haupt, Q. Su, S. De Silva, S. Hossain, T. Griffin, T. Satogata

Physics Faculty Publications

We propose to develop advanced ML models, such as physics informed neural network (PINN) based surrogate models, to accurately represent accelerator phase space transport. These surrogate models will enable precise diagnosis and prediction of beam phase space evolution along the beamline, facilitating real-time control and optimization. The developed models will be tested using the Upgraded Injector Test Facility (UITF) at Thomas Jefferson National Accelerator Facility (JLab), providing a pathway toward ML-driven enhanced diagnostics and beamline control in operational accelerator environments. The primary aim will be to facilitate this by developing machine learning models that outperform traditional simulations in speed and …

Explainable Physics-Based Constraints On Reinforcement Learning For Accelerator Optimization, Jonathan Colen, Malachi Schram, Kishansingh Rajput, Armen Kasparian

Data Science Faculty Publications

We present a reinforcement learning (RL) framework for optimizing particle accelerator experiments that builds explainable physics-based constraints on agent behavior. The goal is to increase transparency and trust by letting users verify that the agent’s decision-making process incorporates suitable physics. Our algorithm uses a learnable surrogate function for physical observables, such as energy, and uses them to fine-tune how actions are chosen. This surrogate can be represented by a neural network or by an interpretable sparse dictionary model. We test our algorithm on a range of particle accelerator optimization environments designed to emulate the Continuous Electron Beam Accelerator Facility at …

Preliminary Observations From The Relativistic Electron Atmospheric Loss (Real) Satellite Mission, Evzen Selvon, Robyn Millan

Wetterhahn Science Symposium Posters

The Relativistic Electron Atmospheric Loss (REAL) spacecraft (launched in July 2025) is a 3U cubesat designed to measure the precise energies (1 keV – 2MeV) and pitch angles of electrons entering the Earth’s ionosphere. The mission involves Dartmouth, BU, JHUAPL, MSU, and NASA. REAL carries three particle sensors measuring low, medium, and high energies. This work is focused on the ElectroStatic Analyzer (ESA) instrument, designed to measure lower energy electrons (1-40 keV) in the directions parallel and perpendicular to the Earth’s magnetic field. This research aims to identify notable events observed by the REAL spacecraft for future analysis.

Variational Autoencoder Inverse Mapper For Extraction Of Compton Form Factors: Benchmarks And Conditional Learning, Douglas Adams, Md Fayaz Bin Hossen, Joshua Bautista, Gia-Wei Chern, Simonetta Liuti, Marie Boër, Marija Čuić, Michael Engelhardt, Gary R. Goldstein, Huey-Wen Lin, Yaohang Li

Computer Science Faculty Publications

Deeply virtual exclusive scattering processes (DVES) serve as precise probes of nucleon quark and gluon distributions in coordinate space. These distributions are derived from generalized parton distributions (GPDs) via Fourier transform relative to proton momentum transfer. QCD factorization theorems enable DVES to be parameterized by Compton form factors (CFFs), which are convolutions of GPDs with perturbatively calculable kernels. Accurate extraction of CFFs from DVCS, benefiting from interference with the Bethe–Heitler (BH) process and a simpler final state structure, is essential for inferring GPDs. This paper focuses on extracting CFFs from DVCS data using a variational autoencoder inverse mapper (VAIM) and …

The Shms 11 Gev/C Spectrometer In Hall C At Jefferson Lab, S. Ali, A. Ahmidouch, G. R. Ambrose, A. Asaturyan, C. Ayerbe Gayoso, J. Benesch, V. Berdnikov, H. Bhatt, D. Bhetuwal, D. Biswas, P. Brindza, M. Bukhari, M. Burton, R. Carlini, M. Carmignotto, M. E. Christy, C. Cotton, J. Crafts, D. Day, S. Danagoulian, A. Dittmann, D. H. Dongwi, B. Duran, D. Dutta, R. Ent, H. Fenker, M. Fowler, D. Gaskell, A. Hamdi, N. Heinrich, W. Henry, N. Hlavin, T. Horn, G. M. Huber, Y. Ilieva, J. Jarrell, S. Jia, M. K. Jones, M. Junaid, M. L. Kabir, N. Kalantarians, A. Karki, S. J.D. Kay, C. E. Keppel, V. Kumar, S. Lassiter, W. B. Li, D. Mack, S. Malace, J. Mcmahan, A. Mkrtchyan, H. Mkrtchyan, P. Monaghan, C. Morean, P. Nadel-Turonski, G. Niculescu, M. I. Niculescu, A. Nadeeshani, E. Pooser, A. Ramos, J. Reinhold, B. Sawatzky, H. Szumila-Vance, V. Tadevosyan, R. L. Trotta, A. Usman, C. Yero, M. Yurov, S. Zhamkochyan, S. A. Wood, J. Zhang

Physics Faculty Publications

The Super High Momentum Spectrometer (SHMS) has been built for Hall C at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). With a momentum capability reaching 11 GeV/c, the SHMS provides measurements of charged particles produced in electron-scattering experiments using the maximum available beam energy from the upgraded Jefferson Lab accelerator. The SHMS is an ion-optics magnetic spectrometer comprised of a series of new superconducting magnets which transport charged particles through an array of triggering, tracking, and particle-identification detectors that measure momentum, energy, angle and position in order to allow kinematic reconstruction of the events back to their origin at …

K-Long Facility At Jlab, Moskov Amaryan

Physics Faculty Publications

In this talk I present the outline of K-long Facility (KLF) at JLab [1]. It was approved by PAC48 in 2020 to run for 200 days of beamtime, equally divided between liquid hydrogen and deuterium targets, to measure dozens of hyperon states predicted by CQM and LQCD but not yet established. This facility also will allow to measure Kπ scattering in different channels to observe the so-called ᴷ scalar meson and measure its width and position with unprecedented accuracy. Finally, it will be shown that exotic baryons can be measured at this facility in formation reactions with a two-body final …

Mtl_Tx: A Multi-Task Transformer Model For Improved Radiation Time-Series Estimation, Hongfang Zhang, Adam Stavola, Hal Ferguson, Bence Budavari, Hongyi Wu, Chiman Kwan, Jiang Li

Electrical & Computer Engineering Faculty Publications

Controlling radiation doses at potential radioactive facilities is critical to ensuring the safety of both personnel and the public. At the Thomas Jefferson National Accelerator Facility (JLab), multiple sensors are deployed around the three experimental halls to monitor key parameters, including single-beam current, energy levels, current leakage, and radiation values during accelerator operations. In this study, we developed a Multi-task Transformer model, MTL_TX, to accurately estimate radiation doses at sensor locations based on historical data, with the aim of enhancing safety in accelerator facilities and surrounding public areas. To improve estimation accuracy, we integrated two innovative components into the proposed …

The Xpdirc Concept For Next-Generation Dirc Detectors, R. Dzhygadlo, J. Datta, K. Dehmelt, A. Deshpande, T. K. Hemmick, Md. I. Hossain, C. E. Hyde, Y. Ilieva, G. Kalicy, W. J. Llope, P. Nadel-Turonski, C. Schwarz, J. Schwiening, N. Shankman, J. Stevens, N. Wickramaarachchi, C. Woody

Physics Faculty Publications

The next-generation DIRC (xpDIRC) represents a novel detector geometry concept currently being developed for advanced particle identification systems in high-energy physics experiments. Building upon the high-performance DIRC (hpDIRC) designed for the ePIC detector at the Electron-Ion Collider, the xpDIRC introduces a hybrid optical architecture that combines enhanced focusing optics, a wide plate light guide, and a compact expansion volume. Comprehensive Geant4 simulations demonstrate that the xpDIRC hybrid geometry achieves state-of-the-art performance in π/K separation across the entire range of operation.

Physics-Informed Temperature Prediction Of Lithium-Ion Batteries Using Decomposition-Enhanced Lstm And Bilstm Models, Seyed Saeed Madani, Yasmin Shabeer, Michael Fowler, Satyam Panchal, Carlos Ziebert, Hicham Chaoui, François Allard

Electrical & Computer Engineering Faculty Publications

Accurately forecasting the operating temperature of lithium-ion batteries (LIBs) is essential for preventing thermal runaway, extending service life, and ensuring the safe operation of electric vehicles and stationary energy-storage systems. This work introduces a unified, physics-informed, and data-driven temperature-prediction framework that integrates mathematically governed preprocessing, electrothermal decomposition, and sequential deep learning architectures. The methodology systematically applies the governing relations to convert raw temperature measurements into trend, seasonal, and residual components, thereby isolating long-term thermal accumulation, reversible entropy-driven oscillations, and irreversible resistive heating. These physically interpretable signatures serve as structured inputs to machine learning and deep learning models trained on temporally …

Enhanced Hydrophilicity And Self-Cleaning Properties Of Tio₂ Thin Films On Glass For Photovoltaic Applications: Influence Of Precursor Concentration And Light Irradiation, Fatma Refaat, Hany Hashem, Mohamed Mahmoud Gouda, Ibrahim Ahmed, Khaled Abdelwahed, Ahmed Bakr El Basaty

Trends in advanced sciences and technology

This study investigates the modification of glass substrates with TiO₂ thin films to enhance surface hydrophilicity and self-cleaning behavior. The films were deposited on glass by spin coating using different precursor concentrations, followed by thermal treatment. Structural and optical properties were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and UV–Vis spectroscopy, while surface wettability was evaluated through water contact angle measurements. XRD confirmed the formation of pure anatase TiO₂, while FTIR spectra verified the presence of Ti–O and Ti–O–Ti bonds. Wettability analysis showed that films prepared with the lowest precursor concentration exhibited the …

Satellite-Mediated Quantum Clock Synchronization: Towards Precise Timing At A Global Scale, Sage B. Ducoing

LSU Doctoral Dissertations

Accurate timekeeping is essential for scientific and technological advancements, particularly in areas of communication, networking, navigation, and high precision measurements. While many methods of time resolution are already established using classical resources, they fail to combine high precision outcomes with large-scale implementations. Additionally, numerous quantum networking architectures using satellite-assisted methods have demonstrated quantum communication on scales exceeding ground-based methods. For these reasons, we propose the use of a time synchronization method by which pairs of highly time-correlated photons are exchanged between clocks on satellites and clocks on Earth, al- lowing users to reconstruct the time offsets between their clocks. This …

Unsaturated Fatty Acid Oil-Based Microdroplets: A Promising Novel Class Of Microdroplets, Ramiz S. Alejilat

Seton Hall University Dissertations and Theses (ETDs)

Droplet-based microfluidics has rapidly advanced numerous fields, including chemistry, biology, materials science, medicine, food science, and cosmetics. In these systems, fluorocarbon oil combined with fluorinated surfactants is the preferred medium for fluid encapsulation, offering exceptional stability and biocompatibility essential for sensitive biological and chemical processes. However, growing concerns about the environmental and biological risks associated with fluorinated chemicals have prompted a search for alternatives.

This study is the first to explore the use of unsaturated fatty acids derived from emu oil for microdroplet formation. We characterized droplet formation based on flow rates and the presence non-fluorinated surfactant at a certain …

Simulation Of Rocket Response To Electromagnetic Environments Using Finite Element Modeling, Eden Powers

Fall Showcase for Research and Creative Inquiry

The purpose of this project is to develop a rocket model in FEMAP with NX-Nastran to simulate how a rocket might respond when exposed to external electromagnetic conditions. A simplified model of the SpaceX Starship will be constructed and analyzed to explore how various electromagnetic conditions interact with the rocket’s materials and geometry.

Dynamic Lqr Control For Improved Dc Link Voltage Stability In Grid-Integrated Solar Pv System, Peter Makolo, Mwanajuma Gora, Francis Mwasilu, Jackson Justo

Tanzania Journal of Science

The integration of photovoltaic (PV) systems into power grids poses a significant challenge to voltage stability, especially at the DC link. Fluctuations in solar irradiance directly cause power variations and instability in this critical interface. If not properly controlled, this variability can lead to inefficiencies, equipment damage, and widespread grid disturbances. To address the abovementioned challenge, this paper proposes a dynamic converter control strategy designed to enhance DC link voltage stability in grid-integrated solar PV system. The core of the proposed control system is based on a Linear Quadratic Regulator (LQR) mechanism, implemented within a two-stage, PV grid connected system …

Early Theories On Fluid Resistance And Translation Of Euler’S “Dilucidationes De Resistentia Fluidorum”, Sylvio R. Bistafa

Euleriana

In 1763, Euler published Dilucidationes de resistentia fluidorum (Explanations on the resistance of fluids), a memoir that challenges the fluid resistance theories proposed by Isaac Newton and d’Alembert. Euler's work explores the resistance experienced by solid bodies moving through fluids, critiquing both Newton's "common rule" and d’Alembert's paradox, which predicted zero resistance for non-viscous fluids. Euler's treatise is divided into two parts: the first focuses on the mathematical modeling of fluid flow patterns, while the second addresses the calculation of fluid resistance on surfaces. Despite significant advancements, Euler's work remains constrained by the limitations of non-viscous fluid assumptions, ultimately grappling …

Low-Cost Cutaneous Protoporphyrin Ix (Ppix) Detection (Cpd) Device For Follow-Up Monitoring Of Patients After Photodynamic Therapy, Md Asaduzzaman Rasel

Graduate Masters Theses

Background: Photodynamic Therapy (PDT) utilizes specific wavelengths of light to activate photosensitizing chemical compounds, known as photosensitizers, which induce the generation of cytotoxic reactive oxygen species (ROS) for the targeted destruction of cancer cells. Among various photosensitizers for PDT, Protoporphyrin IX (PpIX) is widely employed in oncology and dermatology due to its natural in situ generation via the metabolic conversion of 5- aminolevulinic acid (ALA), a non-phototoxic prodrug. Systemic administration of ALA after 3-6 hr drug delay leads to peak PpIX accumulation in tissues, facilitating therapeutic and diagnostic applications. However, PpIX can persist in the skin for 24–48 hours post-treatment, …

Self Spin-Orbit Torques, Ryan Greening

Electronic Theses and Dissertations

Spin–Orbit torques (SOTs) provide an energy-efficient pathway to control magnetization in nanoscale heterostructures. Recently, spin-orbit coupling within ferromagnets has been shown to generate self spin-orbit torques (SSOTs) on the magnetization itself. Previous work on self spin-orbit torques relies on thick ferromagnets with complicated film structures with chemical disorder or compositional gradients to generate inversion symmetry breaking. This dissertation advances experimental methodology and presents data on the quantification of self spin-orbit torques in magnetic thin films due to the spin-orbit coupling of standard 3d ferromagnets.

First, I develop an oblique-incidence magneto-optical Kerr effect (MOKE) technique that exploits a mirror-assisted double reflection …

Improving High Frequency Absorptive Filters For Quantum Computing, Christopher B. Sutton

Graduate Masters Theses

Coaxial transmission lines in superconducting quantum circuits are subject to infrared radiation (IR) leakage as signals travel from room temperature (≈ 300 K) to low temperature (≈ 10 mK). Current experimental configurations typically include an epoxy based filter on all cables connecting classical devices (pulse generators, VNA, etc.) to the quantum circuit. The epoxy is characterized by its dielectric properties per unit length and acts as an absorber, attenuating IR noise. Historically, such IR filters have been fabricated by the experimentalists who require them, more recently they have become commercially available. This work investigates the performance of filters which were …

Quantum Dot Light Emitting Diodes As A Light Source For Photodynamic Therapy, Hamid El Hamidi

Graduate Doctoral Dissertations

ABSTRACT:

QUANTUM DOT LIGHT EMITTING DIODES AS A LIGHT SOURCE FOR PHOTODYNAMIC THERAPY

Photodynamic therapy is a cancer treatment modality that involves the accumulation of a photosensitizer, exposure to visible light, and the presence of oxygen, resulting in the formation of highly reactive and cytotoxic singlet oxygen. PDT has been shown to be more effective as the fluence rate decreases due to oxygen availability and the absence of photobleaching. On the other hand, Quantum Dot Light Emitting Diodes QLEDs- a new form of light source based on nanoparticles (quantum dots)- emerge as a potentially advantageous light source for certain types …

Phase Nanoscopy With Correlated Frequency Combs, Xiaobing Zhu

Optical Science and Engineering ETDs

In this dissertation a sensing method applying to any physical quantity that modifies optical phase is developed. Two pulses are produced inside a synchronously pumped Optical Parametric Oscillator, generating two identical, undistinguishable frequency combs. The physical quantity to be measured applies a small phase shift/round trip to one of the pulses, resulting in a frequency shift of the corresponding comb. The latter frequency is measured as a beat by interfering the two combs on a detector. A world record resolution, close to the quantum limit, of 0.033 nanoradian (corresponding to 0.006 fm in displacement) is achieved. A detailed analysis of …

Orbital Modulation Of Gamma Rays Up To 100 Tev From Ls 5039, R. Alfaro, M. Araya, J. C. Arteaga-Velázquez, D. Avila Rojas, H. A. Ayala Solares, R. Babu, P. Bangale, E. Belmont-Moreno, A. Bernal, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, U. Cotti, J. Cotzomi, S. Coutiño De León, D. Depaoli, P. Desiati, N. Di Lalla, R. Diaz Hernandez, B. L. Dingus, M. A. Duvernois, K. Engel, T. Ergin, C. Espinoza, K. L. Fan, K. Fang, J. A. Garcia-Gonzalez, H. Goksu, A. Gonzalez Munoz, J. A. Gonzalez, M. M. Gonzalez, J. A. Goodman, S. Groetsch, J. P. Harding, S. Hernandez-Cadena, I. Herzog, J. Hinton, D. Huang, F. Hueyotl-Zahuantitla, P. Huntemeyer, S. Kaufmann, D. Kieda, A. Lara, J. Lee, H. Leon Vargas, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mustafa, M. Najafi, L. Nellen, M. U. Nisa, N. Omodei, E. Ponce, Y. Perez Araujo, E. G. Perez-Perez, C. D. Rho, A. Rodriguez Parra, D. Rosa-Gonzalez, M. Roth, H. Salazar, D. Salazar-Gallegos, A. Sandoval, M. Schneider, G. Schwefer, J. Serna-Franco, A. J. Smith, Y. Son, R. W. Springer, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, E. Varcla, Xiaojie Wang, Z. Wang, I. J. Watson, H. Wu, S. Yu, S. Yun-Carcamo, H. Zhou, C. De Leon

Physics Faculty Research & Creative Works

Gamma-ray binaries are luminous in gamma rays, composed of a compact object orbiting a massive companion star. The interaction between these two objects can drive relativistic outflows, either jets or winds, in which particles can be accelerated to energies reaching hundreds of teraelectronvolts (TeV). However, it is still debated where and under which physical conditions particles are accelerated in these objects and ultimately whether protons can be accelerated up to PeV energies. Among the well-known gamma-ray binaries, LS 5039 is a high-mass X-ray binary with an orbital period of 3.9 days that has been observed up to TeV energies by …

Studying Effect Of Temperature On Photovoltaic Characteristics Of Photovoltaic Modules Based On Cigs Solar Cells, Farrux Anvar O‘G‘Li Akbarov, Anvar Akbarovich Alimov

Technical science and innovation

The article presents the experimental results of the temperature dependence of the load current-voltage characteristics of a solar photovoltaic (PV) module based on a polycrystalline semiconductor binary compound Cu(In,Ga)Se₂ under normal sunlight P_rad=800±5 W/m², in a temperature range of (32÷60) ^оС. It was found that the temperature dependence of the photocurrent has two slopes, which is explained by a change in the generation-recombination mechanism. An increase in the short-circuit current with an increase in the temperature of the photovoltaic module is explained by an increase in the drift length of minority charge carriers, due …

Red Forest, Lucas Shilts

Senior Project

Sustaining large numbers of astronauts on Mars will require greenhouses capable of supplementing astronaut dietary needs. Lower solar irradiation and high levels of ionizing radiation on the Martian surface complicate the growth of crops on the red planet. Crops on Mars must be protected from radiation sources while still receiving sufficient illumination to grow. This research seeks to develop a Martian greenhouse illumination and heating design capable of efficiently providing plants the illumination and warmth needed while protecting them from the Martian radiation environment. This research explores a design for a direct-light subsurface Martian greenhouse which employs sun-tracking mirrors, vertical …

Numerical Approach To The Optimization Of The Bandwidth Tunability Of A Non-Cascaded Multifunctional Optical Filter, Ramon Benedict L. Lapina, Benjamin B. Dingel, Clint Dominic Bennett

Ateneo Innovation Center

Previously, we reported a multifunctional optical filter which is a Photonic Integrated Circuit (PIC)–based, noncascaded bandpass filter wherein the Ring Resonators-based Direct-Coupled-All-Pass Filter (D-APF) and Cross-coupled All-pass Filter (C-APF) are attached to each of the arms of a single Mach Zehnder Interferometer (MZI). This device is an alternative platform to the conventional platform of programmable photonic filters that does not rely on combining different photonic elements to implement various filter functionalities. For one, it can generate (i) Narrowband Filter, (ii) Asymmetric Interleaver (AI) and (iii) Symmetric Interleaver (SI) responses by varying limited number of specific parameters of the device. It …

Developing Sky Plots Of Rocket Launches From Gps Scintillation Data, Ishaan Dey, Kshitija Deshpande

Beyond: Undergraduate Research Journal

Sky plots displaying GPS satellite and rocket launch trajectories are developed to determine the spatial correlation between satellites that display ionospheric scintillations and heavy thrust-producing rockets. The trajectories of three major Falcon Heavy and Artemis 1 rocket launches are used within this paper. Python code is utilized to compute and plot Ionospheric Pierce Point (IPP) coordinates which are then used to produce satellite trajectories from the receiver's point of view. Rocket latitude, longitude, and altitude data is integrated within the code to provide extensive detail into the location of the rocket in relation to GPS satellites that displayed scintillations from …

Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati

Makara Journal of Science

The growth of a porous anodic aluminum oxide (PAAO) layer with fewer cracks on a tubular substrate is quite challenging. The PAAO layer on a curved surface grows slower than that on a flat surface and is susceptible to cracking. This study aims to improve the crack resistance of the PAAO layer grown on a tubular aluminum substrate by adding ethylene glycol (EG). Each bath contained additive concentrations of 0, 5, 10, and 15 vol% EG. Anodization proceeded for 4 h at a temperature of 10 ℃ using the potentiostatic mode at 25 V in a sulfuric acid bath and …

Development Of A Near Terahertz Backward Wave Oscillator Using Standard Waveguide, Alexander Glick

Electrical and Computer Engineering ETDs

There is a demand for terahertz (THz) frequency radiation sources. Applications include, but are not limited to, imaging for medical and security purposes, biochemical and organic spectroscopy, and velocimetry. Historically, there was a limited supply of THz devices due to technological limitations. In recent years much progress has been made to reduce this “gap” in supply and demand for THz sources. This work proposes a vacuum electronic device that produces high power, extremely high frequency radiation in the G-band, by utilizing a backward wave oscillator (BWO) based on WR3 standard waveguide. This device is compact, fundamentally simple, and has great …