University of Arkansas, Fayetteville
Minnesota State University - Mankato
Liberty University
Department of Chemistry, West Chester University of Pennsylvania
University of Connecticut
University of Massachusetts - Amherst
California Polytechnic State University, San Luis Obispo
University of Nebraska-Lincoln
University of Tennessee - Knoxville
College of the Holy Cross
Measurement Of Proton Light Yield Of Water-Based Liquid Scintillator,
2023
University of California - Berkeley
Measurement Of Proton Light Yield Of Water-Based Liquid Scintillator, E. J. Callaghan, B. L. Goldblum, J. A. Brown, T. A. Laplace, Juan J. Manfredi, M. Yeh, G. D. Orebi Gann
Faculty Publications
The proton light yield of liquid scintillators is an important property in the context of their use in large-scale neutrino experiments, with direct implications for neutrino-proton scattering measurements and the discrimination of fast neutrons from inverse β-decay coincidence signals. This work presents the first measurement of the proton light yield of a water-based liquid scintillator (WbLS) formulated from 5% linear alkyl benzene (LAB), at energies below 20 MeV, as well as a measurement of the proton light yield of a pure LAB + 2 g/L 2,5-diphenyloxazole (PPO) mixture (LABPPO). The measurements were performed using a double time-of-flight method and a …
Recent Advances In Experimental Design And Data Analysis To Characterize Prokaryotic Motility,
2023
Portland State University
Recent Advances In Experimental Design And Data Analysis To Characterize Prokaryotic Motility, Megan M. Dubay, Jacqueline Acres, Max Riekeles, Jay Nadeau
Physics Faculty Publications and Presentations
Bacterial motility plays a key role in important cell processes such as chemotaxis and biofilm formation, but is challenging to quantify due to the small size of the individual microorganisms and the complex interplay of biological and physical factors that influence motility phenotypes. Swimming, the first type of motility described in bacteria, still remains largely unquantified. Light microscopy has enabled qualitative characterization of swimming patterns seen in different strains, such as run and tumble, run-reverse-flick, run and slow, stop and coil, and push and pull, which has allowed for elucidation of the underlying physics. However, quantifying these behaviors (e.g., identifying …
Detection And Diagnosis Of Bacterial Pathogens In Blood And Urine Using Laser-Induced Breakdown Spectroscopy,
2023
University of Windsor
Detection And Diagnosis Of Bacterial Pathogens In Blood And Urine Using Laser-Induced Breakdown Spectroscopy, Emma J.M. Blanchette
Electronic Theses and Dissertations
The aim of this thesis is to expand on and improve the existing techniques used for detecting and identifying bacterial pathogens in clinical specimens with laser-induced breakdown spectroscopy (LIBS). Specifically, the existing experimental procedures, including bacterial sample preparation and data acquisition, as well as the data analysis with chemometric algorithms were investigated. Substantial reductions in LIBS background signal were achieved by implementing rigorous cleaning steps and the introduction of the use of ultrapure water. Following this, a database of LIBS spectra was acquired from specimens of E. coli, S. aureus, E. cloacae, M. smegmatis, and P. …
Atom-Specific Probing Of Electron Dynamics In An Atomic Adsorbate By Time-Resolved X-Ray Spectroscopy,
2022
Stockholm University
Atom-Specific Probing Of Electron Dynamics In An Atomic Adsorbate By Time-Resolved X-Ray Spectroscopy, Simon Schreck, Elias Diesen, Martina Dell'angela, Chang Liu, Matthew Weston, Flavio Capotondi, Hirohito Ogasawara, Jerry Larue, Roberto Costantini, Martin Beye, Piter S. Miedema, Joakim Halldin Stenlid, Jörgen Gladh, Boyang Liu, Hsin-Yi Wang, Fivos Perakis, Filippo Cavalca, Sergey Koroidov, Peter Amann, Emanuele Pedersoli, Denys Naumenko, Ivaylo Nikolov, Lorenzo Raimondi, Frank Abild-Pedersen, Tony F. Heinz, Johannes Voss, Alan C. Luntz, Anders Nilsson
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The electronic excitation occurring on adsorbates at ultrafast timescales from optical lasers that initiate surface chemical reactions is still an open question. Here, we report the ultrafast temporal evolution of x-ray absorption spectroscopy (XAS) and x-ray emission spectroscopy (XES) of a simple well-known adsorbate prototype system, namely carbon (C) atoms adsorbed on a nickel [Ni(100)] surface, following intense laser optical pumping at 400 nm. We observe ultrafast (∼100 fs) changes in both XAS and XES showing clear signatures of the formation of a hot electron-hole pair distribution on the adsorbate. This is followed by slower changes on a few picoseconds …
Density Functional Theory (Dft) Study Of A Binary Mixture Of Mbba And Paa Liquid Crystal For Thz Application,
2022
Department of Physics, School for Physical & Decision Sciences, Babasaheb Bhimrao Ambedkar University, Uttar Pradesh 226025, India
Density Functional Theory (Dft) Study Of A Binary Mixture Of Mbba And Paa Liquid Crystal For Thz Application, Mirtunjai Mishra, Narinder Kumar, Pawan Singh, B. S. Rawat, Reena Dhyani, Devendra Singh, Devesh Kumar
Makara Journal of Science
The present scenario expresses the electro-optical effect of abinary mixture of MBBA and PAA liquid crystal studied under the impact of the electric field in THz frequency. The binary mixture has a negative order parameter, negative birefringence, and a nematic phase stability under such an electric field. The refractive index remains constant at high THz frequency. The director angle is sensitive to THz frequency, contributing to the maximum fluctuation. The atomic contribution of a binary mixture is approximately equal to the molecular contribution. The binary mixture has a remarkably high bandgap. The C-H, O-C, C-N atom stretching, and wagging of …
Trapping And Cooling Of Ca+ For Cold Ion-Radical Collisions,
2022
University of Nevada, Las Vegas
Trapping And Cooling Of Ca+ For Cold Ion-Radical Collisions, Bernardo Gutierrez
Undergraduate Research Symposium Posters
Free radicals are molecules that contain an unpaired valence electron which induces high reactivity. Ion radical reactions are typically exothermic and have low (or zero) activation energy. It is for these reasons that ion-radical reactions are believed to dominate in interstellar clouds where temperatures hover around 3-10K. State-to-state measurements require precision control of both reactants.
Supercontinuum Light Generation Via Non-Linear Effects In Hollow-Core Fiber,
2022
University of Arkansas, Fayetteville
Supercontinuum Light Generation Via Non-Linear Effects In Hollow-Core Fiber, Skyler Gulati
Physics Student Works
The field of non-linear optics has gained traction in the last couple decades due to the variable generation of wavelengths which are less deterministic than within traditional optics. Using non-linear mediums, including hollow-core fibers (HCF), generation of wavelengths spanning into the vacuum ultraviolet (VUV) wavelength range is possible. These short wavelengths can be utilized within electron spectroscopy-based methods of material science like angle-resolved photoemission spectroscopy (ARPES). This technique most often uses specific photoemission lines of atoms in discharge lamps, however, with the frequency dispersion capabilities of HCF, broad band creation can allow for variable wavelength selection through filtering specific wavelengths …
Coupled Spherical-Cavities,
2022
Technion Israel Institute of Technology
Coupled Spherical-Cavities, Stanislav Kreps, Vladimir Shuvayev, Mark Douvidzon, Baheej Bathish, Tom Lenkiewicz Abudi, Amirreza Ghaznavi, Jie Xu, Yang Lin, Lev Deych, Tal Carmon
Publications and Research
In this work, we study theoretically and experimentally optical modes of photonic molecules—clusters of optically coupled spherical resonators. Unlike previous studies, we do not use stems to hold spheres in their positions relying, instead on optical tweezers to maintain desired structures. The modes of the coupled resonators are excited using a tapered fiber and are observed as resonances with a quality factor as high as 107. Using the fluorescent mapping technique, we observe families of coupled modes with similar spatial and spectral shapes repeating every free spectral range (a spectral separation between adjacent resonances of individual spheres). Experimental results are …
Whispering Gallery Modes Of A Triatomic Photonic Molecule,
2022
CUNY Queens College
Whispering Gallery Modes Of A Triatomic Photonic Molecule, Vladimir Shuvayev, Stanislav Kreps, Tal Carmon, Lev Deych
Publications and Research
In this paper, we present the results of numerical simulations of the optical spectra of a three-sphere photonic molecule. The configuration of the system was continuously modified from linear to triangular, in-plane with the fundamental mode excited in one of the spheres and perpendicular to it. We found the relative insensitivity of the spectra to the in-plane deviation from the linear arrangement up to about 110°. For larger angles, the spectra show significant modification consisting of the major spectral peaks splitting and shifting. On the contrary, the spectra are quite sensitive to out-of-plane molecule deviation, even at small angles. Thus, …
Physics 516: Electromagnetic Phenomena (Spring 2023),
2022
University of Pennsylvania
Physics 516: Electromagnetic Phenomena (Spring 2023), Philip C. Nelson
Department of Physics Papers
These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.
An Interactive Simulation And Visualization Tool For Conventional And Aberration-Corrected Transmission Electron Microscopy,
2022
University of Nebraska - Lincoln
An Interactive Simulation And Visualization Tool For Conventional And Aberration-Corrected Transmission Electron Microscopy, Xingzhong Li
Faculty Publications from Nebraska Center for Materials and Nanoscience
Contrast transfer function (CTF) is a vital function in transmission electron microscopy (TEM). It expresses to what extent amplitudes converted from the phase changes of the diffracted waves contribute to the TEM image, including the effects of lens aberrations. Simulation is very helpful to understand the application of the function thoroughly. In this work, we develop the CTFscope as a component in the Landyne software suite, to calculate the CTF with temporal and spatial dumping envelopes for conventional TEM and to extend it to various aberrations (up to fifth order) for aberration-corrected (AC)- TEM. It also includes effects on the …
Remote Surface Optical Phonon Scattering In Ferroelectric Ba0.6Sr0.4Tio3 Gated Graphene,
2022
University of Nebraska-Lincoln
Remote Surface Optical Phonon Scattering In Ferroelectric Ba0.6Sr0.4Tio3 Gated Graphene, Hanying Chen, Tianlin Li, Yifei Hao, Anil Rajapitamahuni, Zhiyong Xiao, Stefan Schoeche, Mathias Schubert, Xia Hong
Xia Hong Publications
We report the effect of remote surface optical (RSO) phonon scattering on carrier mobility in monolayer graphene gated by ferroelectric oxide. We fabricate monolayer graphene transistors back-gated by epitaxial (001) Ba0.6Sr0.4TiO3 films, with field effect mobility up to 23,000 cm2 V−1 s−1 achieved. Switching ferroelectric polarization induces nonvolatile modulation of resistance and quantum Hall effect in graphene at low temperatures. Ellipsometry spectroscopy studies reveal four pairs of optical phonon modes in Ba0.6Sr0.4TiO3, from which we extract RSO phonon frequencies. The temperature dependence of resistivity in graphene can be well accounted for …
Search For A W' Boson Decaying To A Vector-Like Quark
And A Top Or Bottom Quark In The All-Jets Final State At
√S = 13 Tev,
2022
The CMS collaboration
Search For A W' Boson Decaying To A Vector-Like Quark And A Top Or Bottom Quark In The All-Jets Final State At √S = 13 Tev, The Cms Collaboration
Faculty Publications, Department of Physics and Astronomy
A search is presented for a heavy W0 boson resonance decaying to a B or T vector-like quark and a t or a b quark, respectively. The analysis is performed using protonproton collisions collected with the CMS detector at the LHC. The data correspond to an integrated luminosity of 138 fb−1 at a center-of-mass energy of 13TeV. Both decay channels result in a signature with a t quark, a Higgs or Z boson, and a b quark, each produced with a significant Lorentz boost. The all-hadronic decays of the Higgs or Z boson and of the t quark are …
Degree Of Linear Polarization: An Indicator Of Optical Vortex Beam Entanglement,
2022
University of Alabama in Huntsville
Degree Of Linear Polarization: An Indicator Of Optical Vortex Beam Entanglement, Ella James
Summer Community of Scholars Posters (RCEU and HCR Combined Programs)
No abstract provided.
Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques,
2022
Air Force Institute of Technology
Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques, Ashwin P. Rao
Theses and Dissertations
Analytical atomic spectroscopy methods have the potential to provide solutions for rapid, high fidelity chemical analysis of plutonium alloys. Implementing these methods with advanced analytical techniques can help reduce the chemical analysis time needed for plutonium pit production, directly enabling the 80 pit-per-year by 2030 manufacturing goal outlined in the 2018 Nuclear Posture Review. Two commercial, handheld elemental analyzers were validated for potential in situ analysis of Pu. A handheld XRF device was able to detect gallium in a Pu surrogate matrix with a detection limit of 0.002 wt% and a mean error of 8%. A handheld LIBS device was …
Developing Optical Devices And Projects For Teaching Engineering,
2022
Bethel University
Developing Optical Devices And Projects For Teaching Engineering, Nathan D. Lemke, John Mccauley, Tristan E. Noble, Grace Riermann, Ellesa St. George, Nathan C. Lindquist, Keith R. Stein, Karen Irene Rogers
Physics and Engineering Faculty Publications
We are creating a suite of tools and techniques based on optics to be used for teaching a variety of engineering topics. Each tool is intended for non-expert use and without the need for high-end equipment such as vibration-free optical tables. Here we report progress on three such tools: image-plane digital holography for measuring mechanical deformation; schlieren imaging of convective flows using a smart phone; and a simple optical communication protocol using LabVIEW. We will present the designs of the tools and preliminary results from teaching engineering labs and projects with these tools. Specific courses impacted to date include Fluid …
Using Optical Tweezersto Probe Dna Polymerase Kappa’S Binding Mechanism To Dna,
2022
Bridgewater State University
Using Optical Tweezersto Probe Dna Polymerase Kappa’S Binding Mechanism To Dna, Joshua Watts
Honors Program Theses and Projects
The integrity of our DNA is constantly under threat from many internal and external factors. If the cell cannot properly protect the integrity of DNA, errors (lesions) in DNA may form which can lead to cancer. Most of these lesions serve as a roadblock to the protein, DNA polymerase (Pol), that replicates the DNA during cell division. The mechanism that is employed to read through these errors is called translesion DNA synthesis (TLS). During this process, a special class of DNA polymerases known as TLS DNA Pols that can tolerate and bypass the lesions in DNA are employed by the …
Characterizing The Single-Photon State: Quantum Physics Experiments With Single-Photon Sensitivity,
2022
Portland State University
Characterizing The Single-Photon State: Quantum Physics Experiments With Single-Photon Sensitivity, Sheldon Lee Field
University Honors Theses
Coincidence-counting and spontaneous parametric downconversion are central to introductory quantum mechanical experimentation but have remained largely out of reach of undergraduate physics instructors. This thesis summarizes the theory behind light polarization, spontaneous parametric downconversion, birefringent refractive indices, and an affordable self-contained photon coincidence counting unit (CCU). A method for implementing a CCU to demonstrate downconversion is presented, and empirical results are provided.
Hierarchically Structured Photoelectrodes Via Atomic Layer Deposition,
2022
University of Arkansas, Fayetteville
Hierarchically Structured Photoelectrodes Via Atomic Layer Deposition, Justin Rowan Reed Demoulpied
Graduate Theses and Dissertations
In the search for a sustainable method to meet increasing energy needs, solar energy emerges as an underutilized, plentiful resource. Solar intermittency and requirements for transportation necessitate storing solar energy in the form of chemical bonds via artificial photosynthesis. Photoelectrochemical (PEC) water splitting generates hydrogen fuel from solar energy and water. A semiconducting material that successfully meets the complex requirements for building an industrially scalable PEC device has yet to emerge. This is leading to a reevaluation of materials previously overlooked within PEC research, mainly materials with limitations such as minimal charge carrier mobility and propensity to corrosion under illumination …
Using Coherence And Interference To Study The Few Body Dynamics In Simple Atomic Collisions Systems,
2022
Missouri University of Science and Technology
Using Coherence And Interference To Study The Few Body Dynamics In Simple Atomic Collisions Systems, Sujan Bastola
Doctoral Dissertations
"Atomic Collision experiments are best suited to sensitively test the few-body dynamics of simple systems. The few-body dynamics, in turn, can be sensitively affected by interference effects. However, an important requirement to observe interference effects in atomic scattering experiments is that the incoming projectile beam must be coherent. The coherence properties of the incoming projectile can be controlled by the geometry of the collimating slit placed before the target. We performed a kinematically complete experiment where a 75 keV proton beam is crossed with a molecular hydrogen beam to study the dissociative capture process. The motivation for this project was …
