Session BB00: V: Poster Session I (9:00AM - 11:00AM PT)

A Gauss-Bonnet theory of gravitation with torsion and electromagnetic fields

This study focuses on the cosmological characteristics of a flat universe containing an electromagnetic field. By incorporating Gauss-Bonnet gravitational corrections, it analyzes the kinematic equations based on torsion cosmology and modifies the gauge field equations. This leads to the fundamental equations and gravitational properties of flat universe inflation. The addition of the correction terms facilitates the study of the low-energy limit of string theory, making the difficult-to-observe effects of string theory potentially observable. Gauss-Bonnet theory, with its advantage of requiring no extra fundamental fields, modifies the gravitational theory based on General Relativity (GR) and ensures no dynamical effects in four dimensions under the low-energy effective action of string theory. Considering the SU(2) gauge model, a renormalizable Lagrangian is obtained. By modifying the supersymmetric hybrid inflation model with GB terms, the study derives the modified field equations for gauge bosons and the matter field in torsion gauge field GB theory. It also examines the impact of GB terms on the Hubble constant, suggesting observable effects of low-energy string theory. Under the ?^n gravity model and DeFelice-Tsujikawa model, the study further assesses the sensitivity of the GB term coupling parameters to the model, exploring the potential for observational verification.   

Validating Model Predicted Coronal Holes with Syncronic Coronal Hole Maps

This study focuses on predicting space weather by analyzing patterns in coronal mass ejections (CMEs) from the sun. These CMEs can produce rapid solar winds, significantly impacting human activities and satellite operations. Utilizing data from NASA's Solar Dynamics Observatory (SDO, 2010) and the STEREO Observatory, we pinpointed the specific locations of coronal holes using the SDO/AIA and STEREO/EUVI instruments.

We developed a semi-manual method using Python to assess the precision of an existing automatic detection program. This approach confirmed the program's effectiveness in identifying the general shape and location of coronal holes, but also highlighted discrepancies in border delineation. Future work will investigate these discrepancies to enhance the automatic program's accuracy. This research is crucial for advancing our understanding of space weather phenomena and improving predictive models.   

A New Explanation for the Repeating Nested Helical Path of Motion; from the Smallest Particles of Existence, Photons, to Moons, Planets, Stars, Galaxies, etc.!

Celestial objects have a specific orbital path, such as the orbital path of Moon around the Earth, the orbital path of Earth around the Sun, and the Sun in the Milky Way galaxy. All of them are a simple closed curved path.

But, in the real universe, these paths combine with each other willy-nilly. In other words, since the Moon’s motion depends on the Earth, the Earth’s motion depends on the Sun, and the Sun’s one depends on the central black hole of the Milky Way galaxy, the Moon should have a combined path.

The combination of the 1st and 2nd orbits could form a simple helical path. If the third orbit is also added, the combination of these 3 orbital motions creates a complex helical path for the Moon.

Therefore, it can be said that all celestial objects have a simple or complex helical path. As an instance we have explained the captured images from the Hubble and James Webb telescopes. In this paper we have explained that these images represent a galaxy with a complex helical motion path and our prediction is that one of the illuminated rings is missing in this image.

As a result, we will prove that all moving objects in the universe, from photons to galaxies, clusters, etc., have the repeating nested helical path of motion.   

Diffusion model based emulator for synthetic cosmological structure formation

Deep learning generative models have demonstrated great strengths in high quality synthetic images and various scientific tasks; diffusion models learn the target distribution via a forward Markov process by gradually adding Gaussian noise to the clean sample and reversing the Markov chain via a denoising process by a neural network-based noise estimation. In this study, we generate 3-dimensional cosmological dark matter simulation data and extract density fields using cloud-in-cell methods from various random seeds following the particle-mesh (PM) method, and subsequently use this dataset to train diffusion generative models of both unconditional and conditional nature on cosmological simulation snapshots taken from a certain redshift. We then compare their physical metrics such as power spectrum and density PDFs with ground truth to verify and benchmark the authenticity of such methods. The efficient and high-quality generation of synthetic cosmological simulations has significant utility in structure formation studies such as covariance studies or parameter inference; for the conditional diffusion models, generation of cosmological density fields can be modulated by any chosen parameter that is used for conditioning, such as redshift, dark matter density parameters, or other cosmological parameters, making it a highly flexible tool for cosmological emulation.   

Plasma modes in QED super-strong magnetic fields of magnetars and laser plasmas

Ultra-magnetized plasmas, where the magnetic field strength exceeds the Schwinger field of about B_Q ~ 4 x 10¹³ gauss, become of great scientific interest, thanks to the current advances in laser-plasma experiments and astrophysical observations of magnetar emission. These advances demand better understanding of how quantum electrodynamics (QED) effects influence collective plasma phenomena. In particular, Maxwell's equations become nonlinear in the strong-QED regime. Here we present the 'QED plasma framework' which will allow one to systematically explore collective phenomena in a QED-plasma with arbitrarily strong magnetic field. Further, we illustrate the framework by exploring low-frequency modes in the ultra-magnetized, cold, electron-positron plasmas. These results should be important for understanding of a magnetospheric pair plasma of a magnetar and for laboratory laser-plasma experiments in the QED regime.   

A Semi-Supervised Approach To Determine the Number of Exoplanets in a Given Planetary System Based on NASA Exoplanet Archive Data

Accurately determining the number of exoplanets in planetary systems is essential for gaining insight into planetary formation, the search for potentially habitable exoplanets, and the design of future exoplanet missions. Using data on exoplanets from the publicly accessible NASA Exoplanet Archive, unsupervised and supervised machine learning methods were applied to determine the number of exoplanets in a given planetary system. Clustering methods were applied in order to understand the multidimensional dataset and evaluate the potential efficacy of machine learning methods. The accuracies of models applied to this multiclass classification problem with imbalanced classes were obtained and reported, with several models achieving accuracies of over 90%. Applying algorithms including a decision tree, logistic regression, random forest, and support vector machine resulted in model accuracies comparable to similar studies where machine learning was applied to exoplanet data (Schanche et al. 2019). While the resulting model accuracies are on par with previous studies of exoplanet data, higher accuracies may be achieved with the incorporation of additional data from the James Webb Space Telescope (JWST) into this project (Schanche et al. 2019). Although these classification models were successful, due to the ever-changing nature of data on the number of planets present in planetary systems, cluster labels returned from clustering on the data were used as a target variable as a second approach. A significant increase in accuracy resulted, indicating that clustering methods, and specifically semi-supervised learning, hold great potential in identifying undetected exoplanets within known planetary systems.   

Machine Learning Refinements to Metallicity-Dependent Isotopic Abundances

The project aims to use machine learning algorithms to fit the free parameters of an isotopic scaling model to elemental observations. The processes considered are massive star nucleosynthesis, Type Ia SNe, the s-process, the r-process, and p-isotope production. The analysis on the successful fits seeks to minimize the reduced chi squared between the model and the data. Based upon the successful refinement of the isotopic parameterized scaling model, a table providing the 287 stable isotopic abundances as a function of metallicity, separated into astrophysical processes, is useful for identifying the chemical history of them. The table provides a complete averaged chemical history for the Galaxy, subject to the underlying model constraints.   

Calculating Coherence Lengths of Massless Neutrino Oscillation in the Geometric Representation of Clifford Algebra

All experimental data is consistent with massless neutrinos. There exist possibilities other than neutrino rest mass differences to explain the phenomenon of flavor oscillation. What governs amplitude and phase of the flow of energy, of information transmission, is impedance matching. This true in both classical and quantum electrodynamics. The concept got lost in QED, as did the easily visualized geometric representation of Clifford algebra (as opposed to less intuitive matrix representations of Pauli, Dirac...). Their synthesis permits calculation of quantum impedance networks (QINs) of wavefunction interactions, and within these the relative phase shifts at network nodes generated by the three component neutrino wavefunction excitation of the vacuum wavefunction, and the corresponding coherence lengths.   

Measurement of Proton’s Energy Loss Through Thin Gold Film

The National Institute of Standards and Technology (NIST) aims to reduce the systematic uncertainties of the energy spectrum in the neutron's lifetime experiment, but the presence of any "dead" layer inside the detector affects the energy spectrum of low-energy ions. In order to take this factor into account, we conducted this experiment to determine energy loss spectra of proton beam within the "Gold" dead layer, and compare this spectra with the Stopping Power (SP) of Gold from the NIST's database. To that end, we generated 50-200 keV energy proton beam in Gettysburg College's 200 keV Van de Graff proton accelerator and collected the proton counts received by the Si detector, containing Gold dead layer, for different corresponding energy channels using energy spectra measuring software. As a result, we had to evaporate gold onto different batches of circular glass slides, and Si detector within the Gold Evaporator chamber and determined the thickness of gold layers by utilizing UV-Vis Spectroscopy technology, and AFM Technology. Employing these data, we plotted SP of the Gold dead layer versus the kinetic energy of the proton beam using the thickness function of the Gold, and differentiated this plot with the graph of SP of Gold collected from the NIST database.   

Electron-Positron Collisions: A Comparison of WarpX and GUINEA-PIG Simulations

As part of the Snowmass 21 planning exercise, the Advanced Accelerator Concepts community proposed developing multi-TeV linear colliders and considered beam-beam effects for these machines. Such colliders operate under a high disruption regime with a significant number of electron-positron pairs produced from quantum electrodynamic (QED) effects. Thus, it requires a self-consistent treatment of the fields produced by the pairs, which is not implemented in state-of-the-art beam-beam codes such as GUINEA-PIG. WarpX is a parallel, open-source, and portable particle-in-cell code with an active developer community that models QED processes with photon and pair generation in relativistic laser-beam interactions [2]. However, its application to beam-beam collisions has yet to be fully explored. In this work, we benchmark the luminosity spectra, photon spectra, and the coherent pair production processes from WarpX against GUINEA-PIG in ultra-tight collisions and ILC scenarios. This is followed by a run-time comparison to demonstrate the speed-up advantage of WarpX. Ultimately, this work ensures a more robust modeling approach to electron-positron collisions, with the goal of scaling up to 15 TeV. 

[1] T. Barklow et al., “Beam delivery and beamstrahlung considerations for ultra-high energy linear colliders,” Journal of Instrumentation 18, P09022 (2023)

[2] L. Fedeli et al. "Pushing the frontier in the design of laser-based electron accelerators with groundbreaking mesh-refined particle-in-cell simulations on exascale-class supercomputers." 2022 SC22: International Conference for High Performance Computing, Networking, Storage and Analysis (SC). IEEE Computer Society, 2022.   

On the Dependence of Electromagnetic Phenomena on the Relativity of Simultaneity and Their Expression of Knowledge in the Physical World

Maxwell's equations hold in inertial reference frames (irf) moving at a constant velocity relative to one another. In conjunction with the Lorentz coordinate transformation equations (Lctes), the transformation equations for the electric and magnetic field components in these irfs can be derived. As the derivation of the Lctes depends on the relativity of simultaneity (ros), and indeed on the argument on the ros which can be made with either frame the stationary frame and the other frame the moving frame, electromagnetic phenomena indicate that human cognition is involved in the structure and functioning of the physical world and that these ep are an expression of knowledge in the physical world. Also, Einstein’s argument on ros fails because the “moving” human observer (ho) is not in an irf where he can establish simultaneity since the “moving” ho knows he is moving and experiences himself moving, as Rock has shown empirically. Instead, ros is shown when the ho at rest in the stationary irf uses the time and space in his reference frame (rf) that depend on the simultaneity established in his frame to logically DEDUCE RELATIVE to the ho in the moving frame that the light ray used by the ho at rest in the moving rf to attempt to establish simultaneity in the moving rf should be characterized by c+v and c-v. c+v and c-v are central to the Ltces since [c²/(c+v)(c-v)] ^1/2=[1/(1-v²/c²)^1/2. Ros is based on knowledge.   

Graduate Student Perspectives of Written Qualifying Exams

Relatively little research in physics education focuses on graduate student experiences and program elements. This study examines the impact and perceptions of written qualifying exams (QEs) from a student perspective, following recent research which questions the role and utility of such exams. We first explored the experiences and viewpoints of two physics doctoral students before and after taking their QEs using semi-structured interviews, capturing their expectations, preparedness levels, and apprehensions regarding the exam. We also conducted a broader survey in the same department the following year to gain insights into their pre-exam reflections, challenges faced, and overall satisfaction with the examination process. This provided an understanding of the students' experiences, revealing a mix of relief, continued anxiety, and diverse opinions on the exam's relevance to their future research. Additionally, post-QE interviews revealed common themes and sentiments among the student body. Our findings suggest that while students recognize the role of QEs in their academic journey, there is a clear need for better alignment of the exams with the skills and knowledge essential for successful research in physics. The study highlights the discrepancies between student expectations and the actual examination experience, calling for a reevaluation of the structure and content of QEs to better serve doctoral students in physics.   

Meson and Glueball Spectra in Holographic QCD

In holographic QCD, mesons and glueballs are represented by “wavefunctions” satisfying eigenvalue equations in a higher dimensional space. Mesons are confined to a hypersurface in this space, while glueball wavefunctions can be located anywhere. The shape of the extra dimensions dictates the particles’ 4D mass spectrum. In one of the most famous holographic QCD models, the Witten-Sakai-Sugimoto model, these mass spectra are controlled by a single scale.

This presentation details how we found estimates for this mass scale in the Witten-Sakai-Sugimoto model for glueballs and mesons separately. We used PDG data for mesons, and lattice-simulation data for glueballs. We found significant disagreement between the meson and glueball estimates of the mass scale, and investigated a disagreement about the parity assignments of glueballs within holographic QCD. Our results suggest the presence of an additional scale in determining the meson spectrum, possibly related to the shape of the hypersurface the meson wavefunctions occupy.   

Exploring Photoionized Iron Plasma: In-Depth Analysis of Spectral Lines and Advanced Techniques

X-ray spectroscopy serves as a pivotal tool in comprehending celestial objects' composition, temperature, and physical properties. Most notably includes the studying of iron emission lines in black hole accretion disks and X-ray binaries. Despite its significance, current databases like NIST and XSTAR lack experimental testing for transition line energies of many astrophysically relevant ions. The advent of new-generation X-ray telescopes (e.g., ATHENA, Arcus, XRISM) underscores the imperative for accurate transition line energies to ensure data fidelity. Sandia National Laboratories' cutting-edge Z machine replicates astrophysical environments, allowing for more precise line identifications. Building upon previous work on photoionized silicon plasma from Cho et al., our research focuses on photoionized iron plasma from the same device, presenting preliminary results and emphasizing advanced techniques such as Gaussian decomposition and derivative spectroscopy in data analysis. This study contributes insights into the intricacies of photoionized iron plasma and enhances our grasp of astrophysical phenomena.   

Performance Studies of 30-Node (120 Core) Raspberry Pi4 Beowulf Cluster

Raspberry Pi is an emerging technology that can be used to build cluster computers for conducting computational tasks that can be built at a fraction of the cost compared to the conventional rack-mounted cluster computers. We have built a portable table-top 30-node Raspberry Pi4 Beowulf cluster to explore the capabilities of Raspberry Pis to determine how well the Raspberry Pis perform in a cluster computing environment for parallel computational tasks. The Raspberry Pi4 cluster uses PoE to deliver power to each node. The Raspberry Pi4 cluster consists of 120 cores; each node has a quad-core 64-bit Cortex-A72 (ARM v8) CPU connected to a 48-port gigabit ethernet switch and is running the 32bit Raspbian-11 operating system. We have tested the performance of ARM (Advanced RISC Machine) CPUs. We have compared the performance of the 30-node Orchard Raspberry Pi4 cluster with a previously built 33-node Raspberry-Pi (RPi) cluster with 33 cores, which has Raspberry Pi1 Model B+ CPUs running the Raspbian-7 operating system. Both Raspberry Pi clusters use OpenMPI for parallelization across the nodes. We ran three MPI codes using the OpenMPI library for the computational tasks and to conduct benchmark tests. We will present the results that show the performance across the cluster nodes.   

Cubic and quartic Higgs self-coupling parametrizations of di-Higgs production at next-to-leading order

The self-interactions of the Higgs boson are of crucial importance for the large-scale structure of our universe. While the cubic self-coupling strength is constrained by measurements of Higgs-boson pairs at the Large Hadron Collider, we here propose to extend this strategy to the quartic Higgs self-coupling. Thus, we present a novel parametrization of Higgs boson pair cross-section with respect to cubic and quartic Higgs self-couplings at next-to-leading order (NLO). We used POWHEG BOX simulations of Higgs boson pair production in gluon-gluon fusion (ggHH) to achieve these results. We include parametrizations for 13 TeV and 13.6 TeV center-of-mass energies to align with LHC Run 3 energies. 

STEAM Program: binationally boosting scientific curiosity during the annular eclipse.

Since the beginning of time, eclipses have captivated human imagination. Thus, the recent annular eclipse, which passed through sections of Mexico   partially over Guatemala, provided the ideal opportunity to promote STEM-related career options among the next generation.

STEAM Program is a binational effort led by the authors  in México and Guatemala, has reached over 17,000 K-12 students, 11,000 teachers and 1.5 Million participants with the online  Leon Lederman seminars. During the annular eclipse on October 2023, 4 sites in Mexico  and 6 sites in Guatemala  were stablished to follow the astronomical spectacle while  promoting interest in Science, as well as virtual seminars and workshops in collaboration with the GLOBE Program-NASA to train citizen scientists, teachers, and students  to measure temperature,wind speed and cloud measurements using NASA GlobeObserver and the  established protocols.  J. Felix presented the Concert Conference Physics of Music and Astronomy at several locations, including  at the Universidad de las Artes de Yucatán,  the  historical  teather Francisco de Paula y Toro  and at the CVDR  IPN México.  Workshops were delivered at the American Center  and at the UNIVERSUM Museum. 

Thanks to the sponsorship of CAEN, STEAM Program, and Astronomers Without Borders, we were able to provide participants with suitable solar eclipse paper glasses, solar observations and workshops.  

Over 4,000 participants were benefited of these activities. Results obtained from these observations, include light rainfall,decresed air temperature and  wind speed after the totallity of the annular phase).  These observations have contributed to our preparations for the total eclipse of april 2024.