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Many Extensions Of Coulomb’S Law: A Scoping Review, Florentin Smarandache Jan 2024

Many Extensions Of Coulomb’S Law: A Scoping Review, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this paper, Coulomb’s Law is extended from two stationary charged particles, on linear trajectory, to: many charged particles, or quantum level particles, or objects on arbitrary motions (with velocity, acceleration, time delay), on non-linear trajectories, at even superluminal and instantaneous speeds.


Unveiling Quantum Communication: From Bell's Inequality To Neutrosophic Logic, Victor Christianto, Florentin Smarandache Jan 2024

Unveiling Quantum Communication: From Bell's Inequality To Neutrosophic Logic, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this mini-review, we delve into the intriguing realm of quantum communication, spurred by China's recent development of the Tiantong communication satellite. This satellite, shrouded in secrecy, hints at a revolutionary approach to communication that transcends the limitations of conventional signal transmission. We explore the foundational concepts of Bell's inequality and neutrosophic logic, elucidating their roles in understanding the non-local phenomena of quantum entanglement and its potential for secure and rapid communication. Additionally, we examine the connection between Bell's inequality and Shannon information entropy, unveiling the intricate relationship between quantum mechanics and information theory. Through this exploration, we glimpse a …


Possible Evidences For Existence Of An Aether Medium (Or Virtual Inertia/Spin Superfluid Medium), Victor Christianto, Florentin Smarandache Jan 2024

Possible Evidences For Existence Of An Aether Medium (Or Virtual Inertia/Spin Superfluid Medium), Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The presentation explores the possibility of an aether medium, also referred to as a virtual inertia/spin superfluid medium, existing to explain certain physical phenomena. While the concept of an aether has been historically rejected by mainstream physics, recent findings and interpretations offer potential justifications for its reconsideration. After discussions with several physicists, notably Robert N. Boyd, PhD and others, we are convinced that aether medium does exist, or may be called virtual inertia/spin superfluid medium.


Assuming Photon As Extended Point Particle In The Hypersoft Topological Space And Other Hypotheses: Issues And Trend Analysis, Victor Christianto, Florentin Smarandache Jan 2024

Assuming Photon As Extended Point Particle In The Hypersoft Topological Space And Other Hypotheses: Issues And Trend Analysis, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Following our preceding article, where we discussed alternative interpretations of the advanced perihelion of Mercury, the present article revisits the 1919 solar eclipse expedition led by Arthur Eddington, which famously provided the first observational confirmation of Einstein's theory of general relativity. We focus on the deflection of starlight data obtained during the eclipse, a cornerstone of this validation. Here, we explore three alternative explanations for the observed light bending that challenge the sole attribution to general relativity. Firstly, the paper begins by arguing based on criticisms raised by Tullio Levi-Civita, a contemporary mathematician, regarding Einstein's use of pseudo-tensors in his …


A Hybrid Time Series Forecasting Method Based On Neutrosophic Logic With Applications In Financial Issues, Seyyed Ahmad Edalatpanah, Farnaz Sheikh Hassani, Florentin Smarandache, Ali Sorourkhah, Dragan Pamucar, Bing Cui Jan 2024

A Hybrid Time Series Forecasting Method Based On Neutrosophic Logic With Applications In Financial Issues, Seyyed Ahmad Edalatpanah, Farnaz Sheikh Hassani, Florentin Smarandache, Ali Sorourkhah, Dragan Pamucar, Bing Cui

Branch Mathematics and Statistics Faculty and Staff Publications

Rising market demands, economic pressures, and technological advancements have spurred researchers to seek ways to enhance business environments and scientific productivity. Predictive science, crucial in this context, has gained prominence due to the rapid progress in information technology and forecasting algorithms. Time series forecasting, widely used in fields like engineering, economics, tourism, and energy, has inherent limitations with classical statistical methods, leading researchers to explore artificial intelligence and fuzzy logic for more accurate predictions. However, despite extensive efforts to improve accuracy, challenges persist. The research introduces a model aimed at surpassing existing methods in time series forecasting accuracy. This approach …


Three Novel Approaches To Deep Space: Interstellar Travel That Transcend The Limitations Imposed By The Rocket Equation, Victor Christianto, Florentin Smarandache Jan 2024

Three Novel Approaches To Deep Space: Interstellar Travel That Transcend The Limitations Imposed By The Rocket Equation, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

At the time of writing this abstract, we read about Betelgeuse star has exploded in the last few days. While there are various explanations and interpretations on how that event would have impacted this Earth’s inhabitants, our interpretation asserts that there are several chains of stars that act to lock this Earth to the 3D realm, and the exploded Betelgeuse star can be considered as a signal from heaven that we, all Earth inhabitants, are allowed to be elevated to 5D consciousness and to explore the Deep Space beyond this solar system. Therefore, in the present paper, it is considered …


Numerical Investigation And Statistical Analysis Of The Flow Patterns Behind Square Cylinders Arranged In A Staggered Configuration Utilizing The Lattice Boltzmann Method, M. Abid, N. Yasin, M. Saqlain, S. Ul-Islam, S. Ahmad Jan 2024

Numerical Investigation And Statistical Analysis Of The Flow Patterns Behind Square Cylinders Arranged In A Staggered Configuration Utilizing The Lattice Boltzmann Method, M. Abid, N. Yasin, M. Saqlain, S. Ul-Islam, S. Ahmad

Mathematics & Statistics Faculty Publications

Flow past bluff bodies like square cylinders is important in engineering applications, but flow patterns behind staggered cylinder arrangements remain poorly understood. Existing studies have focused on tandem or side-by-side configurations, while offset orientations have received less attention. The aim of this paper is to numerically investigate flow dynamics and force characteristics behind two offset square cylinders using the single relaxation time lattice Boltzmann method. The effects of changing both the Reynolds number (Re = 1-150) and gap spacing ratio (g* = 0.5-5) between the cylinders are analyzed. Instantaneous vorticity contours, time histories of drag and lift coefficients, power spectra …


Numerical Solution Of Hybrid Nanofluid And Its Stability Over Permeable Wedge Sheet With Heat Transfer Analysis, Aisha M. Alqahtani, Zeeshan, Waris Khan, Florentin Smarandache, Nidhal Becheikh, Roobaea Alroobaea, Taseer Muhammad Jan 2024

Numerical Solution Of Hybrid Nanofluid And Its Stability Over Permeable Wedge Sheet With Heat Transfer Analysis, Aisha M. Alqahtani, Zeeshan, Waris Khan, Florentin Smarandache, Nidhal Becheikh, Roobaea Alroobaea, Taseer Muhammad

Branch Mathematics and Statistics Faculty and Staff Publications

The inclusion of nanoparticles has the potential to improve the thermal efficiency of the base fluid. The field of nanofluid (NF) dynamics has attracted important attention due to its extensive range of practical uses like fuel cells, solar energy, medication administration, heat transfer, microfabrication, coolant applications, and other related domains. The aim of this study is to scrutinize the impact of Lorentz force, thermal energy, joule heating, heat source and injection parameters, and Brownian and thermoporetic diffusions on the hybrid nanofluid over the moving wedge. The stability inquiry is reported for the existing work in order to confirm the stable …


A Data-Driven Machine Learning Approach For Electron-Molecule Ionization Cross Sections, Allison Harris, Josh Nepomuceno Jan 2024

A Data-Driven Machine Learning Approach For Electron-Molecule Ionization Cross Sections, Allison Harris, Josh Nepomuceno

Faculty publications – Physics

Despite their importance in a wide variety of applications, the estimation of ionization cross sections for large molecules continues to present challenges for both experiment and theory. Machine learning (ML) algorithms have been shown to be an effective mechanism for estimating cross section data for atomic targets and a select number of molecular targets. We present an efficient ML model for predicting ionization cross sections for a broad array of molecular targets. Our model is a 3-layer neural network that is trained using published experimental datasets. There is minimal input to the network, making it widely applicable. We show that …


Tau Leptons In The Search For Charged Higgs Bosons, Juan Carlos Cardenas Jr Jan 2024

Tau Leptons In The Search For Charged Higgs Bosons, Juan Carlos Cardenas Jr

Physics Dissertations - Archive

The Standard Model (SM) of particle physics, a gracefully crafted collection of particle theories, has made an astounding number of accurate predictions about the properties of particles and the fundamental laws that govern our universe. Among its long list of remarkable successes are the unification of the electromagnetic and weak forces, the prediction of elementary particles such as the Higgs boson, and its ability to precisely predict a wide range of particle cross-sections and branching fractions which have been verified experimentally.

Yet despite its immense predictive power, some major problems with the standard model are its failure to accommodate dark …


Novel Time Projection Chamber Techniques With Applications Towards Neutrinoless Double Beta Decay Searches, Nicholas K. Byrnes Jan 2024

Novel Time Projection Chamber Techniques With Applications Towards Neutrinoless Double Beta Decay Searches, Nicholas K. Byrnes

Physics Dissertations - Archive

One of the highest priority endeavors in nuclear and particle physics is the search for Neutrinoless Double Beta Decay (0νββ). The observation of 0νββ would prove that the neutrino is a Majorana particle i.e. its own antiparticle, offering a mechanism by which the matter-antimatter asymmetry observed in our universe could be explained. This theoretical decay mechanism is only energetically favored in certain neutron-rich isotopes and, if found, would be the rarest decay process ever observed. To compete with the exceedingly long half-life of 0νββ, all contemporary searches are focused on the following detector performance metrics: Increasing the instrumented isotopic mass …


A Closer Look At The Fabrication Of Some Doped Metal Ions In Borophosphate Glass System And Their Structural, Elastic, Optical, And Gamma-Ray Shielding Characteristics, Elsayed Salama, W. M. Abd-Allah, S. Marzouk, M. S. Gaafar Jan 2024

A Closer Look At The Fabrication Of Some Doped Metal Ions In Borophosphate Glass System And Their Structural, Elastic, Optical, And Gamma-Ray Shielding Characteristics, Elsayed Salama, W. M. Abd-Allah, S. Marzouk, M. S. Gaafar

Basic Science Engineering

Borophosphate host glasses doped with zinc oxide (ZnO), titanium dioxide (TiO2), tellurium dioxide (TeO2), or cerium oxide (CeO2) were synthesized using rapid quenching techniques. Fourier transform infrared (FTIR) spectra, along with deconvoluted FTIR spectra, were recorded in the 400–4000 cm􀀀 1 range. Using the models of Tauc and Urbach, the optical energy band gaps of these glasses were found to be 3.212, 3.289, 3.262, 3.087, and 2.475 eV respectively. Due to the incorporation of different metal ions into the prepared glasses, the density increased and the molar volume decreased, making the glass structure highly compact. Since the elastic moduli are …


Student Performance In Modern Physics In An Active, Partially-Flipped Classroom, Scott Yarbrough Jan 2024

Student Performance In Modern Physics In An Active, Partially-Flipped Classroom, Scott Yarbrough

Physics Dissertations - Archive

The effectiveness of the flipped classroom and hybrid-flipped (partially flipped, partially lecture-based) method of instruction has been extensively studied for high school and introductory undergraduate physics courses, and it has been shown to increase student understanding and performance. However, few studies have been done for upper-level undergraduate courses, and even fewer have been done for virtual courses. In Spring 2021 and Fall 2023, a fully virtual, hybrid-flipped Modern Physics course was taught, primarily to a class of primarily juniors and seniors, with some sophomores. All were STEM majors. The same course, with a similar enrolment and demographic of students, was …


Physics-Informed Neural Networks (Pinns) And Inverse Pinns For The Modeling And Parameter Estimation Of Electric Pumps In Liquid-Propellant Rocket Engines, Logan Mcfarland Jan 2024

Physics-Informed Neural Networks (Pinns) And Inverse Pinns For The Modeling And Parameter Estimation Of Electric Pumps In Liquid-Propellant Rocket Engines, Logan Mcfarland

Theses and Dissertations

This thesis presents a machine learning (ML) based approach to both model and estimate the parameters of an electric pump system that is used in liquid-propellent rocket engines. This is accomplished by utilizing Physics-Informed Neural Networks (PINNs) and inverse Physics-Informed Neural Networks (iPINNs). In an extreme system such as a liquidpropellent rocket engine, accurate control and efciency is imperative for successful performance. The electric pump system is inherently nonlinear and its dynamics are governed by ordinary diferential equations (ODEs). While entirely approachable, these nonlinear dynamics create a challenge in achieving precise control and accurate parameter estimations. Utilization of a PINN …


Modeling The Dynamics Of Radiation Belt Electrons And Ring Current Protons, Xingzhi Lyu Jan 2024

Modeling The Dynamics Of Radiation Belt Electrons And Ring Current Protons, Xingzhi Lyu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Earth’s inner magnetosphere is a highly dynamic region with various charged particle populations and current systems. The radiation belts, composed of relativistic electrons and protons, is an environment that can pose significant risks to both spacecraft and humans in space; while the fluctuations of ring current, an electric current flowing around the earth consisting of energetic electrons and ions, can lead to severe disruptions in ground-based electrical systems. In this dissertation, we first modeled the long-term evolution of ring current protons based on the measurements of Van Allen Probes. By implementing a 1D radial diffusion model with charge exchange loss, …


Analysis Of Macular Pigment Carotenoids In Human Blood Serum Of Glaucoma Patients As A Measure Of Ocular Health: A Raman Spectroscopic Study., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne Jan 2024

Analysis Of Macular Pigment Carotenoids In Human Blood Serum Of Glaucoma Patients As A Measure Of Ocular Health: A Raman Spectroscopic Study., Joy Udensi, Ekaterina Loskutova, James Loughman, Hugh J. Byrne

Datasets

Carotenoids are a major component of the human diet and have been widely studied for their antioxidant, and vision protection roles in the human body, and dietary supplementation is promoted in particular for ocular health. An initial trial (European Nutrition in Glaucoma Management (ENIGMA)), which assessed macular pigment optical density (MPOD) as well as ocular structural, functional and perceptual parameters before and after the 18-month supplementation of glaucoma patients with macular pigment (MP) carotenoids (lutein, zeaxanthin, meso-zeaxanthin), confirmed supplementation significantly improved the clinical ocular health of participants. Blood contains all major dietary carotenoids, presenting it as a suitable and efficient …


Applications Of Independent And Identically Distributed (Iid) Random Processes In Polarimetry And Climatology, Dan Kestner Jan 2024

Applications Of Independent And Identically Distributed (Iid) Random Processes In Polarimetry And Climatology, Dan Kestner

Dissertations, Master's Theses and Master's Reports

The unifying theme of this thesis is the characterization of “perfect randomness,” i.e., independent and identically distributed (IID) stochastic processes as these are applied in physical science. Two specific and mathematically distinct applications are chosen: (i) Radar and optical polarimetry; (ii) Analysis of time series in meteorology. In (i), IID process of a special kind, namely, with a distribution defined by symmetry, is used to link its multivariate Gaussian density to uniformity on the Poincaré sphere. This “statistical ellipsometry” approach is then used to relate polarimetric mismatches or imbalances to ellipsometric variables and suitably chosen cross-correlation measures. In (ii), recently …


Dependence Of Energy Transfer On Curvature Similarity In Collisions Involving Curved Shock Fronts, Justin Cassell Jan 2024

Dependence Of Energy Transfer On Curvature Similarity In Collisions Involving Curved Shock Fronts, Justin Cassell

Dissertations, Master's Theses and Master's Reports

In high-speed collisions of projectiles, pressure exerted by a resulting shock wave is so high that even solids begin to flow and hydrodynamics becomes relevant. Jetting results from hydrodynamic instability driving the evolution of an interface following shock loading. Our emphasis in this dissertation is mitigation of instabilities via several shocks and, specifically, the transfer of energy from a shock wave to another object. To that end, in 2022 and 2023 while on-site, we adapted Lawrence Livermore National Laboratory (LLNL) to explore the effects of shock front geometry on the transfer of energy during shock collisions via numerous computer simulations. …


Les-C Turbulence Models And Fluid Flow Modeling: Analysis And Application To Incompressible Turbulence And Fluid-Fluid Interaction, Kyle J. Schwiebert Jan 2024

Les-C Turbulence Models And Fluid Flow Modeling: Analysis And Application To Incompressible Turbulence And Fluid-Fluid Interaction, Kyle J. Schwiebert

Dissertations, Master's Theses and Master's Reports

In the first chapter of this dissertation, we give some background on the Navier-Stokes equations and turbulence modeling. The next two chapters in this dissertation focus on two important numerical difficulties arising in fluid flow modeling: poor mass-conservation and nonphysical oscillations. We investigate two different formulations of the Crank-Nicolson method for the Navier-Stokes equations. The most attractive implementation, second order accurate for both velocity and pressure, is shown to introduce non-physical oscillations. We then propose two options which are shown to avoid the poor behavior. Next, we show that grad-div stabilization, previously assumed to have no effect on the target …


Study Of Particle Accelerators In The Universe With The Hawc Observatory, Rishi Babu Jan 2024

Study Of Particle Accelerators In The Universe With The Hawc Observatory, Rishi Babu

Dissertations, Master's Theses and Master's Reports

HESS J1809-193 is an unidentified TeV source discovered in 2007 by the High Energy Stereoscopic System(H.E.S.S.) Collaboration. The emission originates in a region that is rich in cosmic-ray accelerators, including several supernova remnants and pulsars, including SNR G11.1+0.1, SNR G11.0-0.0, and the young radio pulsar PSR J1809-1917. Originally classified as a pulsar wind nebula candidate, recent studies show the peak of the TeV region overlapping with a system of molecular clouds and revising the original classification for other scenarios, including a pure hadronic scenario. This dissertation presents the morphological and spectral study of HESS J1809-193 using 2139 days of data …


Halide-Assisted Growth Of Transition Metal Dichalcogenides, Vinaayak Sivam Balasubramaniam Jan 2024

Halide-Assisted Growth Of Transition Metal Dichalcogenides, Vinaayak Sivam Balasubramaniam

Dissertations, Master's Theses and Master's Reports

Monolayers of transition metal dichalcogenides (TMDCs) have attracted significant attention as the rare two-dimensional (2D) semiconducting materials with a direct energy band gap. Chemical vapour deposition (CVD) is one of the scalable techniques to grow atomically thin TMDC monolayers in high quality, but it requires high growth temperature. Herein we report the growth of MoS2, WS2 and MoSe2 by a one-step halide-assisted CVD method using NaCl and KCl as the catalysts. These halides could reduce the growth temperature of TMDCS by reacting with the precursors (TMDC powders) to form volatile intermediate compounds as the growth species. We use optical microscopy, …


2d Direct Numerical Simulation Of Low-Prandtl Number Rayleigh-Bénard Convection, Reed Downs Jan 2024

2d Direct Numerical Simulation Of Low-Prandtl Number Rayleigh-Bénard Convection, Reed Downs

Dissertations, Master's Theses and Master's Reports

A two-dimensional (2D) direct numerical simulation (DNS) of Rayleigh-Benard convection (RBC) was performed at Rayleigh number (Ra) = 10^6 and Prandtl number (Pr) = 0.021. The simulation was run using the Boussinesq approximation on a square grid of 5184 spectral elements using Nek5000. The simulation was started from a conductive state, with non-permeable, isothermal horizontal walls and non-permeable, adiabatic vertical walls. After reaching a steady state, where the Nusselt number (Nu) converged to 6.2, the simulation was run for 60 freefall-averaged dimensionless time units. Time-averaged thermal boundary layers on the top and bottom plates were found to consist of ejection, …


Global Analysis Of The Neutron Magnetic Form Factor, Joseph P. Jayne Jan 2024

Global Analysis Of The Neutron Magnetic Form Factor, Joseph P. Jayne

Honors Theses and Capstones

Protons and neutrons, the nucleons, are made up of smaller particles called quarks. Nucleons have three valence quarks, which are the dominant contributors to its properties, as well as sea quarks (quark-antiquark pairs) and gluons. The distribution of the charge and magnetization of these particles is described by the electric and magnetic form factors. These form factors can be measured with scattering experiments since they directly affect the particle’s cross section. Neutron form factors are challenging to measure because a pure neutron target will decay very fast and is not viable for experiments. Instead, targets like 2H and 3H are …


Quest For An Optimal Spin-Polarized Electron Source For The Electron-Ion Collider, J. Biswas, E. Wang, O. Rahman, J. Sharitka, K. Kisslinger, Adam Masters, S. Marsillac, T. Lee Jan 2024

Quest For An Optimal Spin-Polarized Electron Source For The Electron-Ion Collider, J. Biswas, E. Wang, O. Rahman, J. Sharitka, K. Kisslinger, Adam Masters, S. Marsillac, T. Lee

Electrical & Computer Engineering Faculty Publications

Superlattice GaAs photocathodes play a crucial role as the primary source of polarized electrons in various accelerator facilities, including the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson National Laboratory and the Electron-Ion Collider (EIC) at Brookhaven National Laboratory. To increase the quantum efficiency (QE) of GaAs/GaAsP superlattice photocathodes, a Distributed Bragg Reflector (DBR) is grown underneath using metal-organic chemical vapor deposition (MOCVD). There are several challenges associated with DBR photocathodes: the resonance peak may not align with the emission threshold of around 780 nm, non-uniform doping density in the top 5 nm may significantly impact QE and spin polarization, …


Thermal Diffusivity And Acoustic Properties Of Nb Thin Films Studied By Time-Domain Thermoreflectance, Md. Obidul Islam, Hani Elsayed-Ali Jan 2024

Thermal Diffusivity And Acoustic Properties Of Nb Thin Films Studied By Time-Domain Thermoreflectance, Md. Obidul Islam, Hani Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

The thermal diffusion and acoustic properties of Nb impacts the thermal management of devices incorporating Nb thin films such as superconducting radiofrequency (SRF) cavities and superconducting high-speed electronic devices. The diffusion and acoustic properties of 200-800 nm thick Nb films deposited on Cu substrates were investigated using time-domain thermoreflectance (TDTR). The films were examined by X-ray diffraction, scanning electron microscopy, and atomic force microscopy. The grain size and thermal diffusivity increase with film thickness. The thermal diffusivity increased from 0.100± 0.002 cm2s-1 to 0.237± 0.002 cm2s-1 with the increase in film thickness from 200 …


Accelerating Cavity Fault Prediction Using Deep Learning At Jefferson Laboratory, Md M. Rahman, A. Carpenter, K. Iftekharuddin, C. Tennant Jan 2024

Accelerating Cavity Fault Prediction Using Deep Learning At Jefferson Laboratory, Md M. Rahman, A. Carpenter, K. Iftekharuddin, C. Tennant

Electrical & Computer Engineering Faculty Publications

Accelerating cavities are an integral part of the continuous electron beam accelerator facility (CEBAF) at Jefferson Laboratory. When any of the over 400 cavities in CEBAF experiences a fault, it disrupts beam delivery to experimental user halls. In this study, we propose the use of a deep learning model to predict slowly developing cavity faults. By utilizing pre-fault signals, we train a long short-term memory-convolutional neural network binary classifier to distinguish between radio-frequency (RF) signals during normal operation and RF signals indicative of impending faults. We optimize the model by adjusting the fault confidence threshold and implementing a multiple consecutive …


Parametrization Of Fluid Models For Electrical Breakdown Of Nitrogen At Atmospheric Pressure, Shirshak K. Dhali Jan 2024

Parametrization Of Fluid Models For Electrical Breakdown Of Nitrogen At Atmospheric Pressure, Shirshak K. Dhali

Electrical & Computer Engineering Faculty Publications

In the transient phase of an atmospheric pressure discharge, the avalanche turns into a streamer discharge with time. Hydrodynamic fluid models are frequently used to describe the formation and propagation of streamers, where charge particle transport is dominated by the creation of space charge. The required electron transport data and rate coefficients for the fluid model are parameterized using the local mean energy approximation (LMEA) and the local field approximation (LFA). In atmospheric pressure applications, the excited species produced in the electrical discharge determine the subsequent conversion chemistry. We performed the fluid model simulation of streamers in nitrogen gas at …


Transfer Learning For Field Emission Mitigation In Cebaf Srf Cavities, K. Ahammed, J. Li, A. Carpenter, C. Tennant, R. Suleiman Jan 2024

Transfer Learning For Field Emission Mitigation In Cebaf Srf Cavities, K. Ahammed, J. Li, A. Carpenter, C. Tennant, R. Suleiman

Electrical & Computer Engineering Faculty Publications

The Continuous Electron Beam Accelerator Facility (CEBAF) operates hundreds of superconducting radio frequency (SRF) cavities in its two linear accelerators (linacs). Field emission (FE) is an ongoing operational challenge in higher gradient SRF cavities. FE generates high levels of neutron and gamma radiation leading to damaged accelerator hardware and a radiation hazard environment. During machine development periods, we performed invasive gradient scans to record data capturing the relationship between cavity gradients and radiation levels measured throughout the linacs. However, the field emission environment at CEBAF varies considerably over time as the configuration of the radio-frequency (RF) gradients changes or due …


Direct Measurement Of Microwave Loss In Nb Films For Superconducting Qubits, B. Abdisatarov, D. Bafia, A. Murthy, G. Eremeev, H. E. Elsayed-Ali, J. Lee, A. Netepenko, C. P. A. Carlos, S. Leith, G. J. Rosaz, A. Romanenko, A. Grassellino Jan 2024

Direct Measurement Of Microwave Loss In Nb Films For Superconducting Qubits, B. Abdisatarov, D. Bafia, A. Murthy, G. Eremeev, H. E. Elsayed-Ali, J. Lee, A. Netepenko, C. P. A. Carlos, S. Leith, G. J. Rosaz, A. Romanenko, A. Grassellino

Electrical & Computer Engineering Faculty Publications

Niobium films are a key component in modern two-dimensional superconducting qubits, yet their contribution to the total qubit decay rate is not fully understood. The presence of different layers of materials and interfaces makes it difficult to identify the dominant loss channels in present two-dimensional qubit designs. In this paper, we present the study that directly correlates measurements of RF losses in such films to material parameters by investigating a high-power impulse magnetron sputtered (HiPIMS) film atop a three-dimensional niobium superconducting radio frequency (SRF) resonator. By using a 3D SRF structure, we are able to isolate the niobium film loss …


X-Ray Absorption And Related Studies In Superconducting Devices And Magnetic Thin Films, Ghadendra Bahadur Bhandari Jan 2024

X-Ray Absorption And Related Studies In Superconducting Devices And Magnetic Thin Films, Ghadendra Bahadur Bhandari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Superconducting and magnetic thin films are commonly used in sensors for analytical detectors, especially those that operate at very low temperatures, often below 1 Kelvin. These highly sensitive detectors, capable of functioning across a broad range of wavelengths, have garnered significant interest in scientific research. The focus of this thesis is to address a material challenge associated with an emerging technology known as microwave kinetic inductance detectors (MKIDs). The research involves the study of Al/Si and Al-Mn/Si-based thin films, as well as an investigation into the magnetic properties of LaMnO₃ thin films. LaMnO₃, a perovskite thin film that plays a …