Physics Commons^™

Search For Axion-Like Particles Through Nuclear Primakoff Production Using The Gluex Detector, J. R. Pybus, T. Kolar, B. Devkota, P. Sharp, B. Yu, O. Hen, E. Piasetzky, S. N. Santiesteban, A. Schmidt, A. Somov, Y. Soreq, H. Szumila-Vance, S. Adhikari, C. S. Akondi, C. Ayerbe Gayoso, V. V. Berdnikov, H. Bhatt, D. Bhetuwal, M. M. Dalton, A. Deur, R. Dotel, C. Fanelli, J. Guo, T. J. Hague, D. W. Higinbotham, N. D. Hoffman, P. Hurck, I. Jaegle, A. Karki, W. Li, V. Lyubovitskij, H. Marukyan, M. D. Mccaughan, M. E. Mccracken, S. Oresic, Z. Papandreou, C. Paudel, S. Ratliff, E. M. Seroka, S. Somov, I. Strakovsky, K. Suresh, A. Thiel, B. Zihlmann

Physics Faculty Publications

We report on the results of the first search for the production of axion-like particles (ALPs) via Primakoff production on nuclear targets, ᵧA → aA, in the "SRC-CT" experiment using the GlueX detector at Jefferson Lab. This search uses an integrated luminosity of 100 pb^-1 center dot nucleon on a C-12 target with a real photon beam of energies 6 < Eᵧ < 10.8 GeV, and explores the mass region of 200 < m(a) < 450 MeV via the decay a → ᵧᵧ. This mass range is between the pi⁰ and η meson masses, which enables the use of the measured η meson production rate to obtain absolute bounds on the ALP production with reduced sensitivity to …

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 …

Unlv Title Iii Aanapisi & Mcnair Scholars Institute Research Journal 2024, Jesica Godinez-Paredes, Kian Hassankhan, Apia Hickman, Robin Ruth Kee, Kevin Ayala Pineda, Briana Melendez, Kalli Ramos, Saturn L. Reyes, Fabian Leija, Selena Pepe, Silva Topchyan, Celeste Ainsley, Mayra Arzate, Jessica Balistreri, Zantana Ephrem, Mirella Jasso, Karl Panou, Nichole Pelaez, Miklo Alcala, Akshay Dave, Mey Mey Heng, Michael Finkle, Janessa Montenegro, Reynafe Naol Aniga, Victor Mejia, Angelica G. Diaz, Anayeli Flores-Garibay, Kari Lee Joe Goold, Samantha Hernandez, Lianelys Cabrera Martinez, Caitlin Reynolds, Kimberly N. Usbeck, Abdulrahman Alahdal, Angelica Diaz, Willaine Mae Kahano, Raquel Jackson, Cecia Ruiz-Hernandez, Kers Ung-Watson, Yessenia Henriquez, Vanessa Marie Booth, Alexia Brown, Darlyn Magana, Bianca Navarro, Nicholas Pereira, Gia Renemae Calip, Lucky Heng, Ralph Sagun, Lucas Abreu, Alexandra Maria Acosta, Tristan Benally, Cosset Hernandez Pena, Adrian Montenegro, Cierra Paaaina-Daquioag, Nicole Torosian, Tracy Fuentes, Julissa Martinez, Medina Mcallister, Michal Newhouse-Van Vlerin, Tiria Carr, Nima Abkenar, Isabella Aceituno, Yuhan Bi, Victoria Campos, Melika Cummings, Zachary J. Johnigan, Alexis Sotolongo-Marin

McNair Journal

Journal articles based on research conducted by undergraduate students in the AANAPISI, LSAMP, and McNair Scholars Program.

Table of Contents

About AANAPISI

Dr. Chris Heavey, Interim President

Dr. Keith Rogers, Vice President for Student Affairs

Ms. Zhanna Aronov, Associate Vice President for Retention & Outreach

Volume 15, Connor Thompson, Emily Steffenhagen, Emily Robertson, Luis Fernando Dos Reis, Emily Farmer, Samuel Villa, Robert Allison, Zachary Chessor, Megan Borden, Austin Burnett, Larry W. Grant Jr., Tristan Marowski, Emma Moore, Pearl Siff

Incite: The Journal of Undergraduate Scholarship

Introduction Dr. Amorette Barber, Director, Office of Student Research

From the Editor Dr. Hannah Dudley-Shotwell

Artist’s Statement Connor Thompson

On Mentorship Dr. John Miller

The Meat of the Matter: Alien, Human, and Animal in Terry Bisson’s “They’re Made Out of Meat” by Emily Steffenhagen

“Please REBLOG!”: An Ethical Analysis of Doxxing, Internet Vigilantism and Racists Getting Fired by Emily Robertson

Journaling: Paper Has More Patience Than People by Luis Fernando Dos Reis

The Effects of Climate Change on the Archaeological World by Emily Farmer

Lowered Seat Height Does Not Impair Wingate Performance in Untrained Cyclists by Samuel Villa, Robert Allison, …

Exploring Crystal Polymorphism In Additive-Assisted Chemical Vapor-Deposited Transition Metal Chalcogenides And Oxides, Lawrence Kirimi Mubwika

Graduate Theses, Dissertations, and Problem Reports (ETD)

Crystal polymorphism is a phenomenon in which compounds with the same chemical formula can be crystallized into different crystal structures. This phenomenon can be observed in elemental materials, such as diamond and graphite, as well as in compounds, such as the trigonal (1H) or octahedral (1T) prismatic MoS₂. Crystals can also exhibit polytypism by stacking different polymorphs in a certain order, with the stacking sequence determining the variation between polytypes. Although all polymorphs and polytypes have the same chemical composition, each polymorph and polytype possesses unique electronic and physical properties.

This study explores the additive-assisted chemical vapor deposition …

Backgrounds Study And Ai-Powered Waveform Processing For Legend Experiment, Laxman Paudel

Dissertations and Theses

Neutrinoless Double-Beta Decay (0$\nu \beta \beta $) is a presumed rare nuclear decay process and is considered the most promising way to prove the Majorana nature of neutrinos, that is, neutrinos are their own antiparticles. The discovery of \zero decay would also enhance our understanding of nuclear physics, astrophysical observations, and physical processes in the early Universe. The Large Enriched Germanium Experiment for Neutrinoless Double-Beta Decay (LEGEND) is a phased $^{\mathrm{76}}$Ge-based 0$\nu \beta \beta $ decay experimental program, aiming for the discovery potential of a half-life of 0$\nu \beta \beta $ beyond 10$^{\mathrm{28}}$ years. The first phase, LEGEND-200, comprises 200 …

Advancements In Glitch Subtraction Systems For Enhancing Gravitational Wave Data Analysis: A Brief Review, Mohammad Abu Thaher Chowdhury

Physics & Astronomy Faculty Publications

Glitches are transitory noise artifacts that degrade the detection sensitivity and accuracy of interferometric observatories such as LIGO and Virgo in gravitational wave astronomy. Reliable glitch subtraction techniques are essential for separating genuine gravitational wave signals from background noise and improving the accuracy of astrophysical investigations. This review study summarizes the main glitch subtraction methods used in the industry. We talk about the efficacy of classic time-domain techniques in real-time applications, like matched filtering and regression methods. The robustness of frequency-domain approaches, such as wavelet transformations and spectral analysis, in detecting and mitigating non-stationary glitches is assessed. We also investigate …

Microwave Simulations Of A Beam Position Monitor And Circuit Designs Assisting Its Beam Testing, Marc Jacob Crowell

Graduate Research Theses & Dissertations

Beam position monitors (BPMs) are non-destructive diagnostic devices widely used in particle accelerators. I will first introduce the need for precision beam position measurement in particle accelerators, and then provide an overview of various types of BPMs. For the first part of my work, I focus on the design and simulation of a button-BPM. Microwave and wakefield simulations were performed to characterize the output signals. Such a design could find a potential application at the Argonne Wakefield Accelerator (AWA) at the Argonne National Laboratory. Although no BPMs have been fabricated to this date, a future beam experiment will be needed …

Theory Of Ultrafast Spin Crossover In Divalent Iron Systems, William Baker

Graduate Research Theses & Dissertations

A theory to account for the ultrafast, i.e. femtosecond timescale, singlet to quintet spin crossover in divalent iron molecules is developed. The model considers an iron cluster with ligands extending in all 6 cardinal directions initially at rest in a low spin singlet ground state. An optical excitation excites an electron from the d orbitals to the ligands, changing the system from the metal centered (MC) singlet state to the metal to ligand charge transfer (MLCT) singlet state. Experimentally, it is known that the system eventually relaxes into the quintet MC state, but there are no satisfactory explanations that model …

Using Ex-Situ And In-Situ Mössbauer Spectroscopy To Study The Degradation Of Nafe(1−X)(Ni0.5mn0.5)X O2 Batteries, Iddrisu Bachokun Abdul Razak

Graduate Research Theses & Dissertations

Sodium-ion batteries are an attractive alternative to traditional lithium-ion batteries due to their low cost and eco-friendly components. The Fe3+/Fe4+ redox reaction provides similar operating voltages and specific energy densities to that of lithium-ion batteries. Mössbauer spectroscopy is a useful x-ray technique for measuring the chemical environment inside of the metal enclosure of batteries. In particular, it can measure the relative concentration of Fe3+/Fe4+ ions as a function of the battery’s voltage. In this dissertation ex-situ and in-situ Mössbauer spectroscopy were used to map out the effect of various electrolytes on the performance of NaFe(1−x)(Ni0.5Mn0.5)xO2 batteries. This was done by …

Cold Testing Of A Prototype Superconducting Radiofrequency Electron Gun And Ancillary Systems For The Lcls-Ii-He Project, Kaela Michele Villafania

Graduate Research Theses & Dissertations

Argonne National Laboratory is collaborating with Michigan State University (MSU), Helmholtz-Zentrum Dresden-Rossendorf (HZDR), and Stanford Linear Accelerator Center (SLAC) on the design, fabrication, and testing of a prototype superconducting radiofrequency (SRF) gun for the planned LCLS-II-HE upgrade at SLAC. This electron source will enable the generation of higher-brightness beams at a high repetition rate opening the path to expand LCLS-II-HE FEL performances. This thesis focuses on the cold testing of the prototype gun cavity and ancillary structures including the fundamental input-power coupler and tuning system. Numerical simulations are also presented to understand fields inside of the cavity as well as …

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 …

A Floquet Solver For Time Periodic Open Quantum Systems, Fenton Ross Clawson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Computational physics has been a backbone of experimental and theoretical physics since the 1940’s, when the first nuclear bomb and ballistic simulations were per- formed at Los Alamos Laboratory. Nowadays, however, simulation of open quan- tum systems has been formalized into coding packages and user-friendly functions, such as QuTiP or Qiskit, which allow users to simulate these systems without hav- ing the in-depth knowledge required to build the computational backbone from the ground-up. With the shift in modern quantum physics towards the realization of quantum computation, a strong computational background is still necessary to lend validity to theoretical results and …

Experimental Verification And Time-Resolved Bispectral Analysis Of Nonlinear Coupling In The Toroidicity-Induced Alfv´En Eigenmode Spectrum, Gregory Allen Riggs

Graduate Theses, Dissertations, and Problem Reports (ETD)

In magnetically-confined fusion devices, the toroidicity-induced Alfv´en eigenmode (TAE) is a well-studied, weakly stable solution of the linearized ideal magnetohydrodynamic (MHD) equations. Due to intrinsic coupling of poloidal harmonics of the shear Alfv´en wave (SAW) in toroidal geometry, the rotational transform of magnetic field lines modulates the effective index of refraction, ensuring gaps in the so-called “Alfv´en continuum.” Experimental verification of theoretical predictions for various parameters of interest (i.e., frequency, mode structure, instability threshold, etc.) is established in the literature.

We present the first systematic study of TAE-TAE phase coherence in an experimental device, using the DIII-D tokamak. Crucially, nonlinear …

Magnetotransport Properties Of Dirac Semimetal Taco2te2 And Ferromagnetic Weyl Semimetal Co3sn2s2, Samuel Pate

Graduate Research Theses & Dissertations

This dissertation investigates the magnetotransport properties of topological semimetals, specifically focusing on the Dirac semimetal TaCo2Te2 and the Weyl semimetal Co3Sn2S2. In TaCo2Te2, I observed extremely large magnetoresistance that violates Kohler’s rule. Extended Kohler’s rule can be applied with a calculation of Hall factor at low temperatures. I also explored the applicability of the two-band and four-band models of carrier analysis and correlate the region where Kohler’s rule is obeyed to the four-band model. In Co3Sn2S2, I explored the angle-dependent anomalous Hall effect (AHE) near the Kagome plane, revealing a tunable AHE under applied fields and an abrupt disappearance of …

Non-Symmetry In The Shock Refraction At A Closed Interface As A Recovery Mechanism, Anna Markhotok

Physics Faculty Publications

The possibility of a shock wave recovery at a discrete closed interface with a heated gas has been investigated. A two-dimensional model applied to conditions of optical discharges featuring spherical, elliptical, and drop-like configurations demonstrated that non-symmetry in the shock refraction contributes to the specific mechanism of recovery other than simply its compensation. Even though the full restoration of the hypersonic flow state does not occur in a strict sense of it, clear reverse changes toward the initial shape of the shock front eventually take place, thus creating an appearance of a full recovery seen in experiments. From analysis of …

Estimation Of Methyl Orange Dye's Molar Absorptivity Using A Photoresistor-Based Photometer, Patricia M. Ludovice, Ramon M. Delos Santos

Physics Faculty Publications

The need to further develop solar cell technology, particularly on dye-sensitized solar cells (DSSCs), drives absorption studies of various chemical species. In this study, absorbance analysis of methyl orange (MO) dye was performed using the adapted and modified photoresistor-based photometer of Adams-McNichol et al. [1]. The research aims to improve the stability of the reference setup, while maintaining the accuracy of absorbance results it yields. The methodology includes photometer fabrication, MO dye sample preparation, and the evaluation of MO dye's molar absorptivity in an aqueous solution. Results show that the estimated molar absorptivity of MO using the voltage readings from …

Advancements In Nuclear Magnetic Resonance, Electron Paramagnetic Resonance, Multipole Moments, And Lie Group Proprieties, Zhichen Liu

Graduate Thesis and Dissertation 2023-2024

To accurately solve the general nuclear spin state function in Nuclear Magnetic Resonance (NMR), a rotation wave approach was employed, allowing the reference frame to rotate in sync with the oscillating magnetic field. The spin state system was analogously treated as a Rubik's Cube, ensuring the diagonalization of only the time-dependent part of the state function. Although Gottfried's equation (1966) aligns with transitions between specific spin states m and m′, his second rotation contradicts the conservation of angular momentum, resulting in inaccuracies for spin states with initial phase shifts or entangled states. Contrarily, Schwinger (1937) efficiently computed the coefficients for …

Re-Evaluation Of Lethal Radiation Dose In Drosophila Melanogaster Using 350 Kev Electrons, Dariia Hozhenko

All Graduate Theses, Dissertations, and Other Capstone Projects

Radiation dosimetry from a 350 KeV electron beam and its impact on Drosophila melanogaster response serve as the focal points of this study. While previous research has established an LD50 (lethal radiation dose for 50 % of the population) exceeding 452 Gy across mainly all developmental stages, this investigation extends the understanding by examining dose-dependent differences throughout development, from the pupae stage into adulthood. Fruit flies, irradiated at their most sensitive stage, the egg phase, displayed a notable reduction in effective LD50, especially when accounting for long-term effects. Specifically, the LD50 values decreased to approximately 59 Gy for the maximum …

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 …

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 …

Conventions, Definitions, Identities, And Other Useful Formulae, Robert A. Mcnees Iv

Physics: Faculty Publications and Other Works

As the name suggests, these notes contain a summary of important conventions, definitions, identities, and various formulas that I often refer to. They may prove useful for researchers working in General Relativity, Supergravity, String Theory, Cosmology, and related areas.

Ultradeep Atca Imaging Of 47 Tucanae Reveals A Central Compact Radio Source, Alessandro Paduano, Arash Bahramian, James C. A. Miller-Jones, Adela Kawka, Tim J. Galvin, Liliana E. Rivera Sandoval, Sebastian Kamann, Jay Strader, Laura Chomiuk, Craig O. Heinke

Physics & Astronomy Faculty Publications

We present the results of an ultradeep radio continuum survey, containing ∼480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 μJy beam−1 at 5.5 GHz, 940 nJy beam−1 at 9 GHz, and 790 nJy beam−1 in a stacked 7.25 GHz image. This is the deepest radio image of a globular cluster and the deepest image ever made with the Australia Telescope Compact Array. We identify ATCA J002405.702-720452.361, a faint (6.3 ± 1.2 μJy at 5.5 …

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 …

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

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, …

Constraining Models For The Origin Of Ultra-High-Energy Cosmic Rays With A Novel Combined Analysis Of Arrival Directions, Spectrum, And Composition Data Measured At The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, K. Almeida Cheminant, A. Almela, B. Fick, D. Nitz, A. Puyleart, Et Al.

Michigan Tech Publications

The combined fit of the measured energy spectrum and shower maximum depth distributions of ultra-high-energy cosmic rays is known to constrain the parameters of astrophysical models with homogeneous source distributions. Studies of the distribution of the cosmic-ray arrival directions show a better agreement with models in which a fraction of the flux is non-isotropic and associated with the nearby radio galaxy Centaurus A or with catalogs such as that of starburst galaxies. Here, we present a novel combination of both analyses by a simultaneous fit of arrival directions, energy spectrum, and composition data measured at the Pierre Auger Observatory. The …

Hydrodynamics Of Drops And Particles Driven By Marangoni And Diffusiophoretic Forces, Subramaniam Chembai Ganesh

Dissertations and Theses

This study investigates the hydrodynamics of particles and drops driven by forces generated by an asymmetrical physical and chemical surrounding environment. In the first part, a novel colloidal motor design driven by surface tension forces is proposed, utilizing an active Janus particle encapsulated in an immiscible liquid drop to form a compound drop/particle. Marangoni forces induced by asymmetric solute adsorption at the liquid-liquid interface of the drop propels the compound system. The propulsion speeds of the motor are analyzed for various relative sizes and configurations of the Janus particle and the encapsulating drop and the effects of varying the transport …

Leveraging Redundancy As A Link Between Spreading Dynamics On And Of Networks, Felipe Xavier Costa

Electronic Theses & Dissertations (2024 - present)

A constant quest in network science has been in the development of methods to identify the most relevant components in a dynamical system solely via the interaction structure amongst its subsystems. This information allows the development of control and intervention strategies in biochemical signaling and epidemic spreading. We highlight the relevant components in heterogeneous dynamical system by their patterns of redundancy, which can connect how dynamics affect network topology and which pathways are necessary to spreading phenomena on networks. In order to measure the redundancies in a large class of empirical systems, we develop the backbone of directed networks methodology, …

Characterization Of Nasa Cold Atom Laboratory Potentials Using Variational Techniques, Samuel O. Oni

College of Graduate Studies: Theses & Dissertations

In a recent atom-interferometry (AI) experiment, conducted aboard the NASA Cold Atom Laboratory (CAL) deployed to the International Space Station (ISS), a Bose-Einstein condensate (BEC) was formed too near to the atom chip wall for the AI experiment to be carried out. To fix this the experimentalists tuned the CAL external magnetic field and atom-chip currents so as to move the BEC away from the atom-chip wall. They then planned to turn the trap off and allow it to expand in place (since there is no gravity on the ISS) in preparation for the AI experiment. Unfortunately, when the trap …