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Articles 1 - 30 of 131
Full-Text Articles in Physics
A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond
A Study Of Data/Monte Carlo Agreement In Charmed Baryon Decays At Belle Ii, Kaitlyn Thurmond
Honors Theses
The Belle II experiment at the SuperKEKB electron-positron accelerator facility in Tsukuba, Japan has a primary goal of searching for new physics beyond the Standard Model of particle physics. Extremely precise measurements of particle decays will be compared with Standard Model predictions in order to expose the presence of new particles and interactions. These measurements are prepared using simulated samples to avoid potential biases when studying the data. The Belle II collaboration produces two types of simulated samples for this purpose. One is produced with consistent calibration payloads and another with payloads calibrated as a function of data taking. This …
An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer
An Analysis Of Detection Asymmetry Using Baryon Decays In Belle Ii, Matthew Mestayer
Honors Theses
The purpose of this study was to determine the detection asymmetry of the Belle II detector using decays of two common baryons, Λ0 → ��π- and Σ+ → ��π0. A Monte Carlo simulation of both decays was used to determine the validity of signal isolation criteria. These criteria were then applied to the Belle II data, allowing for a comparison of the detection asymmetry in the data relative to the simulation. The results show a moderate detection asymmetry when using the Λ0 → ��π- decay, particularly for forward-going baryons. For the Σ+ …
Constraining H0 Via Extragalactic Parallax, Nicholas Ferree
Constraining H0 Via Extragalactic Parallax, Nicholas Ferree
Honors Theses
We examine the prospects for measurement of the Hubble parameter 𝐻0 via observation of the secular parallax of other galaxies due to our own motion relative to the cosmic microwave background rest frame. Peculiar velocities make distance measurements to individual galaxies highly uncertain, but a survey sampling many galaxies can still yield a precise 𝐻0 measurement. We use both a Fisher information formalism and simulations to forecast errors in 𝐻0 from such surveys, marginalizing over the unknown peculiar velocities. The optimum survey observes ∼ 102 galaxies within a redshift 𝐻0max = 0.06. The required errors …
Study Of Missing Mass Background In The Clas12 Detector, Jessie Hess, Gerard P. Gilfoyle, Lamya Baashen
Study Of Missing Mass Background In The Clas12 Detector, Jessie Hess, Gerard P. Gilfoyle, Lamya Baashen
Honors Theses
At Jefferson Lab we use the CLAS12 detector to measure the neutron magnetic form factor. An accurate measurement of the CLAS12 neutron detection efficiency (NDE) is required. We use the nuclear reaction ���� → ��′��+�� as a source of tagged neutrons and obtain the NDE from the ratio of expected neutrons to detected ones. We assume the final state consists of ��′��+�� only, use the ��′��+ information to predict the neutron's position(expected) and then search for that neutron(detected). We select neutrons with the missing mass (MM) technique. We use simulation to validate our methods. We simulated events with the Monte-Carlo …
The Luminous Power Of Accretion Disks In Active Galactic Nuclei, Imogen Jade Courtney
The Luminous Power Of Accretion Disks In Active Galactic Nuclei, Imogen Jade Courtney
Honors Theses
Active Galactic Nuclei (AGN) are the most luminous long-lived objects in the universe. The phenomenon of the immense luminosities we observe for AGN has interested physicists and astronomers for over a century and continues to fascinate scientists today. The work in this thesis aims to provide an introductory exploration of this phenomenon. This thesis uses a simple model of AGN accretion disks that was developed under the standard disk model proposed by Shakura & Sunyev in 1973 under the simplest assumptions. The model accurately demonstrates how physical parameters, such as the temperature, radiative flux, luminosity, and spectra, scale through an …
Detecting High-Lying Rydberg States Using Two-Step Electromagnetically Induced Transparency And Frequency Modulation Spectroscopy Techniques, Kate Jensen
Honors Theses
Resonant optical excitation of high-lying Rydberg states in room temperature 85Rb was investigated using light from two homemade external cavity diode lasers (ECDL). This was done using a ladder schema of the Electromagnetically Induced Transparency (EIT) technique. The approximate EIT wavelengths used were 780 nm (the probe beam) to provide step-wise excitation of valence rubidium electrons from the 5S1/2 → 5P3/2 tran- sition, and then 482 nm (the coupling beam) to excite from the 5P3/2 state to a high-lying Rydberg nD state with an orbital angular momentum = 2. Successful excitation of the Rydberg states was observed using Frequency Modulation …
Particle Swarm Optimization For High Rigidity Spectrometer, Yicheng Wang
Particle Swarm Optimization For High Rigidity Spectrometer, Yicheng Wang
Honors Theses
The goal of this project is to find reliable parameter settings for a multi-dimensional global optimizer to optimize the performance of a large acceptance ion optical system for the requirements of nuclear physics experiments. We develop and test the Particle Swarm Optimization (PSO), a global optimization algorithm designed for continuous multi-dimensional problems, on a large acceptance particle beam separator, the High Rigidity Spectrometer (HRS) at the Facility for Rare Isotope Beams (FRIB), which is a laboratory specializing in the production and experimental study of short-lived nuclear matter. We split the HRS into two sections, the High-Transmission Beamline (HTBL) and the …
Long-Range And Chaotic Active Mixing Of Swimming Microbes In A Vortex Chain Flow, Nghia Le
Long-Range And Chaotic Active Mixing Of Swimming Microbes In A Vortex Chain Flow, Nghia Le
Honors Theses
We present experiments studying the motion and active mixing of swimming mi- crobes in laminar, vortex-dominated fluid flows. We are testing a theory that predicts the existence of swimming invariant manifolds (SwIMs) - invisible, one-way barriers blocking the paths of self-propelled tracers in the flow in one direction. We also pro- pose that the SwIMs together can form chute structures in three-dimensional phase space that facilitate cross-vortex transport of the microbes. We also observe evidence of how these structures promote long-range transport at different non-dimensional velocities (microbe’s velocity relative to flow velocity). Long-range transport is quan- tified by measuring the …
Development Of Quantitative Methods To Study Pfas Using Proton Induced Gamma-Ray Emission, Colin Langton
Development Of Quantitative Methods To Study Pfas Using Proton Induced Gamma-Ray Emission, Colin Langton
Honors Theses
Per- and polyfluoroalkyl substances (PFAS) are man-made chemicals that have become a major environmental concern. They can be found in a broad range of everyday products and pose a significant risk to the public due to their adverse health effects. They are persistent, bioaccumulate and do not break down in the environment. This project specifically aims to determine the concentration of Fluorine, a key identifier of PFAS, in environmental samples. To do this, we employ proton induced gamma-ray emission (PIGE) to screen for Fluorine within our samples. PIGE is performed at the Union College Ion Beam Analysis Laboratory using a …
Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld
Investigating The Thermodynamics And Seismic Profile Of The Europan Hydrosphere Through Pure-Water Modeling And Saltwater Experiments, Samantha Rosenfeld
Honors Theses
We explore the properties of the hydrosphere on Europa involving both a modeling technique and experimental methods. We perform a computational analysis of the thermodynamic properties for an ideal, pure-water Europan ice shell using a Python programming framework called SeaFreeze. We create four models assuming surface temperatures of either 50 K or 140 K and ice shell thicknesses of either 3 km or 30 km. We observe mostly linear trends for the density and seismic wave velocities with respect to depth and find that surface temperature has the greatest effect on the models. Simultaneously, we experimentally investigate the phase diagram …
External Beam Alignment System For Quantitative Proton Induced Gamma-Ray Emission (Pige) Spectroscopy, Elias Ottens
External Beam Alignment System For Quantitative Proton Induced Gamma-Ray Emission (Pige) Spectroscopy, Elias Ottens
Honors Theses
The effects of pollution on the ecosystem are paramount in our society, permeating air, soil, and drinking water. One contaminant of concern is per- and polyfluoroalkyl substances (PFAS), also referred to as "forever chemicals", which contains fluorine (F), a potentially harmful element to humans. To investigate pollution in the environment, it is necessary to make accurate measurements of the distribution and concentrations of these PFAS chemicals. To do this, soil samples are collected and analyzed using Particle Induced Gamma-ray Emission (PIGE) via the Union College Ion Beam Analysis Laboratory's (UCIBAL) particle accelerator. A 2.2 MeV proton beam comes into contact …
Lifetime Measurement Of The Xi_C^+ Using Belle Ii Monte Carlo, Paul Gebeline
Lifetime Measurement Of The Xi_C^+ Using Belle Ii Monte Carlo, Paul Gebeline
Honors Theses
This analysis uses simulated data from the Belle II experiment to measure the lifetime of the Xi_c^+ baryon. Three different decay modes are investigated to explore the feasibility and accuracy of such measurements at Belle II. The Xi_c^+ lifetime is measured using one of these modes after reducing backgrounds from sources other than the decay of interest. The final result is 464 +/- 15 fs, which is consistent with the expected result of 442 fs within uncertainty. This result shows that Belle II can make competitive measurements of particle properties and decays.
A Performance Analysis Of The Belle Ii Detector, John Stacy
A Performance Analysis Of The Belle Ii Detector, John Stacy
Honors Theses
The Belle II experiment has recently (2018) started data taking at the SuperKEKB electron-positron collider in Tsukuba, Japan. Detector performance studies are necessary to understand early data and prepare for more complex analyses. This study of the proton detection efficiency of the Belle II detector compares real and simulated data to find discrepancies with the intention to provide useful information for detector and calibration experts to better gauge detector performance. It also attempts to improve the characterization of proton identification efficiency at low momenta, which performs poorly under the current fitting model. This helps analysts exploring final states that include …
Monte Carlo Study Of Lepton Flavor Universality Violation In B Decays With Belle Ii Simulation, Sakul Mahat
Monte Carlo Study Of Lepton Flavor Universality Violation In B Decays With Belle Ii Simulation, Sakul Mahat
Honors Theses
Belle II, the first super B-Factory experiment, is designed to make precise measurements of weak interaction parameters and search for New Physics beyond the Standard Model of particle physics. The Standard Model of particle physics is a theory that classifies all known elementary particles and describes three of the four known fundamental forces in the universe. Physics beyond the Standard Model that addresses the theoretical developments needed to explain the deficiencies in the Standard Model is often referred to as New Physics. One of the assumptions of the Standard Model is that the couplings of particles that mediate the weak …
Study Of Deexcitation Intensities To The K-Shell In Iron 55, Eric Helgemo
Study Of Deexcitation Intensities To The K-Shell In Iron 55, Eric Helgemo
Honors Theses
55Fe radioactive sources are used for x-ray calibration due to the long half-lives of 2.73 years and the optimal energies of the peaks. The source used in the experiment was generated using Western Michigan University’s Tandem Van de Graff accelerator to produce a 6 MeV proton beam which induced a 55Mn(p, n)55Fe reaction on a 10 μm 55Mn target. The emissions from this target were then measured using a silicon lithium drift x-ray detector to determine the number of instances of deexcitation through kα and kβ modes. The preliminary data discussed showed a lower relative deexcitation rate of 6.67 between …
A Fractal Geometry For Hydrodynamics, Jonah Mears
A Fractal Geometry For Hydrodynamics, Jonah Mears
Honors Theses
Experiments have shown that objects with uneven surfaces, such as golf balls, can have less drag than those with smooth surfaces. Since fractal surfaces appear naturally in other areas, it must be asked if they can produce less drag than a traditional surface and save energy. Little or no research has been conducted so far on this question. The purpose of this project is to see if fractal geometry can improve boat hull design by producing a hull with low friction.
Estimation Of Pure B Power In Polarized Cmb Data Via Gibbs Sampling., Joseph Sterling
Estimation Of Pure B Power In Polarized Cmb Data Via Gibbs Sampling., Joseph Sterling
Honors Theses
In the search for effective processes to estimate E and B spectra from polarized data, Gibbs Sampling has proven to be a powerful method. In the search for B modes, it is essential to avoid a false positive detection due to contamination from the larger E component. It is therefore of interest to combine Gibbs sampling with methods to “purify” the B modes, ensuring that a B-mode detection is robust. This goal can be achieved by compelling the Gibbs Sampler to estimate a pure B spectrum. The method we chose to implement involves an artificially inflated E spectrum, which “forces” …
Pixe Analysis Of Heavy Metals In Soil Along The East River, Mia Villeneuve
Pixe Analysis Of Heavy Metals In Soil Along The East River, Mia Villeneuve
Honors Theses
We collected samples of soil from along the East River in Queens, New York, near the Hell Gate Bridge, on the Astoria Park side of the bridge in 2019 and on the Randall’s Island Park side in 2021. We performed proton-induced X-ray emission (PIXE) analysis on the samples and found that soil closer to the Hell Gate Bridge contained higher concentrations of heavy metals, specifically lead and zinc. Many of the soil samples contained lead concentrations greater than the EPA standard of 400 ppm. We also performed PIXE analysis on a sample of the paint used on the bridge and …
Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow
Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow
Honors Theses
Radiation is a form of energy that can damage materials at an atomic level. This has implications for the mobility of radioactive waste through containment materials. We are characterizing atomic defects in materials by using Electron-Positron Annihilation Lifetime Spectroscopy (EPALS). When an electron and positron come into contact with each other, they annihilate and release two antiparallel 511-keV gamma rays. In a pristine crystalline sample, positrons can easily annihilate with electrons, but in a sample with vacancies/defects in the crystal structure, positrons take longer to annihilate. Therefore, the more vacancies in a sample, the longer the average lifetime of a …
Apparatus Improvement And Characterisation For Experiments On Ultra-Cold Plasmas., Jakub Bystrický
Apparatus Improvement And Characterisation For Experiments On Ultra-Cold Plasmas., Jakub Bystrický
Honors Theses
Apparatus for creating ultra-cold neutral plasmas (UNPs) was improved and data on plasma expansion was collected. We increase the trapping efficiency of a quadrupole magneto-optical trap (MOT) by installing a tapered amplifier to increase the power of the cooling laser used to trap atoms. We achieve an improvement in density of trapped atoms from 1 x 1010 cm-3 to 2.5 - 4.5 x 1010 cm-3. In addition, to improve precision and decrease systematic error, the magnetic field induced by inductive current in the MOT's anti-helmholtz coils was suppressed. This was achieved by installing a KEPCO …
An Argument For The Second Nuclear Era: Salvaging The Atomic Age In Response To Climate Change, Ian Sager
An Argument For The Second Nuclear Era: Salvaging The Atomic Age In Response To Climate Change, Ian Sager
Honors Theses
No abstract provided.
Analysis Of Possible Hybrid Meson Decay, Jasper Bergh
Analysis Of Possible Hybrid Meson Decay, Jasper Bergh
Honors Theses
This research looked at data from the GlueX experiment at the Thomas Jefferson National Accelerator Facility to search for evidence of the π1(1600) particle, an exotic hybrid meson, decaying to an eta' and π0. We specifically looked into decays of the eta' to an eta, π+, and π-, with the eta decaying to 3 πo's. We successfully reconstructed an eta from the 3 πo's, and an eta' from the eta, π+, and π-. However, we did not observe the π1(1600), but, a 6:1 ratio of signal to background in the eta' mass. With more statistics this would be a viable …
A Theoretical Study Of Synchronous Proton Transfer In (Hf)N, (H2O) N, And (Hcl) N Where N = 3, 4, 5, Johnny Yang
A Theoretical Study Of Synchronous Proton Transfer In (Hf)N, (H2O) N, And (Hcl) N Where N = 3, 4, 5, Johnny Yang
Honors Theses
For (HF)n, (H2O)n, and (HCl)n (n = 3 − 5), we have rigorously characterized the structures for the minima and transition states for synchronous proton transfer (SPT) with the CCSD(T) method and aug-cc-pVTZ basis set. The electronic barrier heights (∆E†) associated with these transition states have also been computed with the explicitly correlated CCSD(T)-F12 method and the aug-cc-pVQZ-F12 basis set (abbreviated aQZ-F12). (HCl)n (n = 3 − 5) SPT transition states have not been previously identified to the best of our knowledge, and they have been found …
Cosmological Inflation In N-Dimensional Gaussian Random Fields With Algorithmic Data Compression, Connor A. Painter
Cosmological Inflation In N-Dimensional Gaussian Random Fields With Algorithmic Data Compression, Connor A. Painter
Honors Theses
The leading modern theories of cosmological inflation are increasingly multi-dimensional. The “inflaton field” φ that has been postulated to drive accelerating expansion in the very early universe has a corresponding potential function V , the details of which, such as the number of dimensions and shape, have yet to be specified. We consider a natural hypothesis that V ought to be maximally random. We realize this idea by defining the V as a Gaussian random field in some number N of dimensions. We repeatedly simulate of the evolution of φ given a set of conditions on the “landscape” of V …
Characterization Of Mechanical Responses Of Helical Antenna For Satellite Communications, Scott Chumley
Characterization Of Mechanical Responses Of Helical Antenna For Satellite Communications, Scott Chumley
Honors Theses
The purpose of this work was to identify and analyze the vibrational modes of a helical structure to model the vibrational characteristics of an L-band helical antenna for satellite communications. This project focused on the vibrational modes between 1 and 50 Hz. Using COMSOL Multiphysics finite element modeling of helices were performed to predict mode shapes and frequencies to compare with both continuous wave (CW) and impulsive measurements. In the initial phase of the experimental work, five helical samples were constructed and evaluated. In the second phase of the study, one sample was chosen for more detailed quantitative measurements. In …
Curved Spacetime In The Causal Set Approach To Quantum Gravity, Ayush Dhital
Curved Spacetime In The Causal Set Approach To Quantum Gravity, Ayush Dhital
Honors Theses
Causal Set theory is an approach to quantum gravity. In this approach, the spacetime continuum is assumed to be discrete rather than continuous. The discrete points in a causal set can be seen as a continuum spacetime if they can be embedded in a manifold such that the causal structure is preserved. In this regard, a manifold can be constructed by embedding a causal set preserving causal information between the neighboring points. In this thesis, some of the fundamental properties of causal sets are discussed and the curvature and dimension information of Minkowski, de Sitter, and Anti-de Sitter spaces is …
Exploring Manifoldlike Causal Sets And Their Dimensions, Santosh Bhandari
Exploring Manifoldlike Causal Sets And Their Dimensions, Santosh Bhandari
Honors Theses
Causal Set Theory is an approach to quantum gravity that tries to replace the continuum spacetime structure of general relativity with the spacetime that has the property of discreteness and causality. From the standpoint of causal set theory, our spacetime is made up of discrete points that are causally related to one another. A causal set is said to be manifoldlike if it can be faithfully embedded in a Lorentzian manifold. In this thesis, some of the fundamental properties of causal sets are discussed. The first chapter is devoted to the historical background of quantum gravity with a discussion of …
Mot-Based Lifetime Measurements Of Potassium-39 5p1/2 And 5p3/2 States, Huan Q. Bui
Mot-Based Lifetime Measurements Of Potassium-39 5p1/2 And 5p3/2 States, Huan Q. Bui
Honors Theses
This thesis presents measurements of the lifetimes of 5p1/2 and 5p3/2 of K39 via exciting a cloud of K39 atoms in a magneto-optical trap by a linearly-polarized pulse of 405 nm light followed polarization-specific, time-resolved fluorescence detection. We find that $\tau_{5p1/2} = $ 138.8 $\pm$ 1.6 ns, which is consistent with past measurements \cite{triumf}, \cite{berends} and calculations \cite{safranova}. The $\tau_{5p3/2}$ measurement is naturally more involved since quantum beats due to hyperfine and Zeeman effect are present. Our observation of $\tau_{5p3/2} =$ 137.6 $\pm$ 3.1 ns and $\tau_{5p3/2} =$ 136.0 $\pm$ 2.4 ns, obtained from two slightly different approaches, are compared …
Heel Down And Toe-Off Time Measured With Ultrasonic Doppler System And Force Plate Sensor, Sabin Timsina
Heel Down And Toe-Off Time Measured With Ultrasonic Doppler System And Force Plate Sensor, Sabin Timsina
Honors Theses
Collie Box is a medical device that measures the gait parameters of the person walk- ing in front of it. This device uses the Ultrasonic Doppler system to extract the heel-contact and toe-off times of a person walking within the range of 2-10 meters. These times are used to determine the leg’s swing phase and double stance times. The ultrasonic transducer of 10mm diameter is driven at 40kHz. At the time of the heel-contact and toe-off, foot velocity is zero while the torso part of the human body is still in motion. The wide directivity of 10mm diameter ultrasonic transducer …
Investigatin Actin-Myosin Mechanics To Model Heart Disease Using Fluorescence Microscopy And Optical Trapping, Justin Edward Reynolds
Investigatin Actin-Myosin Mechanics To Model Heart Disease Using Fluorescence Microscopy And Optical Trapping, Justin Edward Reynolds
Honors Theses
Hypertrophic cardiomyopathy (HCM) is a hereditary disease in which the myocardium becomes hypertrophied, making it more difficult for the heart to pump blood. HCM is commonly caused by a mutation in the β-cardiac myosin II heavy chain. Myosin is a motor protein that facilitates muscle contraction by converting chemical energy from ATP hydrolysis into mechanical work and concomitantly moving along actin filaments. Optical tweezers have been used previously to analyze single myosin biophysical properties; however, myosin does not work as a single unit within the heart. Multiple myosin interacts to displace actin filaments and do not have the same properties …