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Yang–Mills at strong vs. weak coupling
In this work, I discuss various situations in which perturbative expansions are used in Yang-Mills theories with asymptotic freedom and establish the limits of its applicability.
Weak Simulation v.0.1
The SPARSIFY algorithm implemented by the code allows for classical simulation of universal quantum computer sample outcomes. The code sparsifies the stabilizer decomposition of a qubit t-tensored T gate magic state to some additive error. This is accomplished by either independent L1 sampling or with correlated L1 sampling to supplement an independent subset, which offers a more efficient decomposition: for a given t, a sparser decomposition is sufficient with correlated L1 sampling to satisfy a given additive error. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. SAND2021-8296 O
Light Transport with Weak Angular Dependence in Fog: Supplemental Code
A MATLAB script for calculating the optical properties of different fog types. This is a supplemental code intended to be published along with a journal paper. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525. SAND2021-1504 O
6-D ELEMENT-BY-ELEMENT PARTICLE TRACKING WITH CRAB CAVITY PHASE NOISE AND WEAK-STRONG BEAM-BEAM INTERACTION FOR THE HADRON STORAGE RING OF THE ELECTRON-ION COLLIDER
The Electron Ion Collider (EIC) presently under construction at Brookhaven National Laboratory will collide polarized high energy electron beams with hadron beams with luminosities up to 10^34 cm?^2 s^?1 in center mass energy range of 20-140 GeV. Crab cavities are used to compensate the geometric luminosity due to a large crossing angle 25 mrad in the EIC. It was found that the phase noise in crab cavities will generate a significant emittance growth for the hadron beams. The phase noise tolerance from the analytical calculation is very small for the Hadron Storage Ring (HSR) of the EIC. In this article, we present our preliminary numerical simulation results with a 6-d symplectic particle tracking to determine the proton emittance growth rate with crab cavity phase noise and beam-beam interaction for the HSR.
Incorporating Galaxy Cluster Triaxiality in Stacked Cluster Weak Lensing Analyses
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Magnetic Reconnection in Strongly-Magnetized, Weakly-Collisional Plasmas: Onset, Turbulence, and Energy-Partition in 3D, Plasmoid-Dominated Regimes
This project is concerned with theoretical and numerical studies of magnetic reconnection. Key areas of focus are the reconnection onset (how reconnection gets started), energy partition (how the magnetic energy gets distributed during a reconnection event), and the effect of background turbulence on reconnection. We aim to shed light on these issues in kinetic plasmas (i.e., plasmas where the collisional mean free path is long compared to the length-scales of interest), with emphasis on 3D geometries.
Hidden Markov Model Application for Unsupervised Clustering of Microseismic Events at CO2 Injection Site Reveals Hidden Zones of Weakness.
Abstract not provided.
Systematic study of projection biases in weak lensing analysis
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Weak-Lensing in the DELVE Survey
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Acoustic Arrivals from Weak Explosive Sources Recorded on Distant Airborne Platforms.
Abstract not provided.
Investigating Shaker-System Stability for Strong and Weak Nonlinear Systems.
Abstract not provided.
The Contour Method: Principle, Applications, Strengths and Weaknesses [Slides]
Abstract not provided.
The Naturally Unnatural Standard Model: Symmetry Remnants at the Weak Scale
The project had significant impact on the success of the Snowmass 2021 Community study undertaken from 2020-2, focused on planning the future of High Energy Physics in the US for the period 2025-35. The PI served as a topical convener for the Energy Frontier, and the work undertaken resulted in the topical group report as well as the final Energy Frontier report. The PI further undertook significant work on electroweak baryogenesis and the possibility of CP violation in the Higgs sector, exploring the matter-antimatter asymmetry of the Universe. Further work was also accomplished in investigating possible new explanations for the anomalous magnetic moment of the muon, measured at Fermilab, showing deviations from the Standard Model expectations.
Modeling and Control of Solar PVs for Large Grid Disturbances and Weak Grids
The purpose of this project is to understand dynamic phenomena by designing dynamic models of utility-sale solar photovoltaic (PV) power plants and their interactions with grids; and construct effective coordination strategies for stability enhancement for solar PVs to respond to rapidly changing grid conditions.
The eXtended virtual element method for elliptic problems with weakly singular solutions
This paper introduces a novel eXtended virtual element method, an extension of the conforming virtual element method. The X-VEM is formulated by incorporating appropriate enrichment functions in the local spaces. The method is designed to handle highly generic enrichment functions, including singularities arising from fractured domains. By achieving consistency on the enrichment space, the method is proven to achieve arbitrary approximation orders even in the presence of singular solutions. The paper includes a complete convergence analysis under general assumptions on mesh regularity, and numerical experiments validating the method’s accuracy on various mesh families, demonstrating optimal convergence rates in the L 2 - and H 1 - norms on fractured or L-shaped domains.
Weak Dispersion of Exciton Landé Factor with Band Gap Energy in Lead Halide Perovskites: Approximate Compensation of the Electron and Hole Dependences
The optical properties of lead halide perovskite semiconductors in vicinity of the bandgap are controlled by excitons, so that investigation of their fundamental properties is of critical importance. The exciton Landé or g-factor g X is the key parameter, determining the exciton Zeeman spin splitting in magnetic fields. The exciton, electron, and hole carrier g-factors provide information on the band structure, including its anisotropy, and the parameters contributing to the electron and hole effective masses. Here, g X is measured by reflectivity in magnetic fields up to 60 T for lead halide perovskite crystals. The materials band gap energies at a liquid helium temperature vary widely across the visible spectral range from 1.520 up to 3.213 eV in hybrid organic–inorganic and fully inorganic perovskites with different cations and halogens: FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 , MAPbI 3 , FAPbBr 3 , CsPbBr 3 , and MAPb(Br 0.05 Cl 0.95 ) 3 . The exciton g-factors are found to be nearly constant, ranging from +2.3 to +2.7. Thus, the strong dependences of the electron and hole g-factors on the bandgap roughly compensate each other when combining to the exciton g-factor. The same is true for the anisotropies of the carrier g-factors, resulting in a nearly isotropic exciton g-factor. The experimental data are compared favorably with model calculation results.