Astrophysics and Astronomy Commons^™

Measurement Of Flow Coefficients In High-Multiplicity P + Au, D + Au, And 3 He + Au Collisions At √S Nn = 200 Gev, Star Collaboration

Physics and Astronomy Faculty Publications

Flow coefficients (v2 and v3 ) are measured in high-multiplicity p + Au, d + Au, and 3 He + Au collisions at a center-of-mass energy of √s NN = 200 GeV using the STAR detector. The measurements utilize two-particle correlations with a pseudorapidity requirement of |η| < 0.9 and a pair gap of |Δη| > 1.0. The primary focus is on analysis methods, particularly the subtraction of nonflow contributions. Four established nonflow subtraction methods are applied to determine vn, validated using the HIJING event generator. vn values are compared across the three collision systems at similar multiplicities; this comparison cancels the final-state effects and isolates the …

Reaction Plane Correlated Triangular Flow In Au+Au Collisions At √S Nn = 3 Gev, Star Collaboration

Physics and Astronomy Faculty Publications

We measure triangular flow relative to the reaction plane at 3 GeV center-of-mass energy in Au+Au collisions at the BNL Relativistic Heavy Ion Collider. A significant v3 signal for protons is observed, which increases for higher rapidity, higher transverse momentum, and more peripheral collisions. The triangular flow is essentially rapidity-odd with a slope at midrapidity, dv3/dy|(y=0), opposite in sign compared to the slope for directed flow. No significant v3 signal is observed for charged pions and kaons. Comparisons with models suggest that a mean field potential is required to describe these results, and that the triangular shape of the participant …

Results On Elastic Cross Sections In Proton–Proton Collisions At √𝑠 = 510 Gev With The Star Detector At Rhic, The Star Collaboration

Physics and Astronomy Faculty Publications

We report results on an elastic cross section measurement in proton–proton collisions at a center-of-mass energy√𝑠 = 510 GeV, obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section is measured in the four-momentum transfer squared range 0.23 ≤ −𝑡 ≤ 0.67 GeV2. This is the only measurement of the proton-proton elastic cross section in this 𝑡 range for collision energies above the Intersecting Storage Rings (ISR) and below the Large Hadron Collider (LHC) colliders. We find that a constant slope 𝐵 does not fit the data in …

Upper Limit On The Chiral Magnetic Effect In Isobar Collisions At The Relativistic Heavy-Ion Collider, Star Collaboration

Physics and Astronomy Faculty Publications

The chiral magnetic effect (CME) is a phenomenon that arises from the QCD anomaly in the presence of an external magnetic field. The experimental search for its evidence has been one of the key goals of the physics program of the Relativistic Heavy-Ion Collider. The STAR Collaboration has previously presented the results of a blind analysis of isobar collisions (96 44 Ru + 96 44 Ru, 96 40 Zr + 96 40 Zr) in the search for the CME. The isobar ratio (Y ) of CME-sensitive observable, charge separation scaled by elliptic anisotropy, is close to but systematically larger than …

Production Of Protons And Light Nuclei In Au+Au Collisions At √S Nn = 3 Gev With The Star Detector, Star Collaboration

Physics and Astronomy Faculty Publications

We report the systematic measurement of protons and light nuclei production in Au+Au collisions at √s NN = 3 GeV by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The transverse momentum (pT ) spectra of protons (p), deuterons (d), tritons (t), 3 He, and 4 He have been measured from midrapidity to target rapidity for different collision centralities. We present the rapidity and centrality dependence of particle yields (dN/dy), average transverse momentum (〈pT 〉), yield ratios (d/p, t/p, 3 He /p, 4 He /p), as well as the coalescence parameters (B2 , B3 ). The 4π yields …

Microstructural, Mineralogical, And Chemical Characterization Of The Handys Bend And Flax Creek Meteorites, Kentucky: Relevance For The Iron Meteorite Record, Ethan S.L. Davis

Theses and Dissertations--Earth and Environmental Sciences

Iron meteorites remain the only material view into planetary cores. Despite their scientific relevance, iron meteorites are relatively rare. In June 2021 and March 2022, the Kentucky Geological Survey received requests to identify two metallic specimens discovered in central Kentucky. The specimens were given the provisional names Handys Bend (3175.2 g) and Flax Creek (286.2 g). The goal of this project is to confirm meteoritic origin, characterize their structures and chemistry, assign genetic classifications, and examine potential relations to previous discoveries. Petrography was conducted using scanning electron microscopy. Mineral phases were examined using X-Ray diffraction crystallography. Chemical compositions were determined …

The Computational Search For Unidentified Central Configurations Of The Newtonian N-Body Problem, Hannah G. Havel

CURE Proceedings

The N-body problem is a field of study in mathematics and physics that involves predicting the motion of particles moving under their mutual gravitational attraction. It is vital in celestial mechanics, such as planning collision-free satellite orbit trajectories. When beginning to understand the N-body problem, we can start by looking at equal masses of these particles or celestial bodies. As particles move, their position and velocity change, both energy and angular momentum are conserved. Sets of constant energy and angular momentum, known as integral manifolds, are higher-dimensional figures that represent constraints of movement to a system. Integral manifolds are described …

Performance Optimization For A Scintillating Glass Electromagnetic Calorimeter At The Eic, J. Crafts, Renee H. Fatemi, T. Horn, D. Kalinkin

Physics and Astronomy Faculty Publications

The successful realization of the EIC scientific program requires the design and construction of high-performance particle detectors. Recent developments in the field of scientific computing and increased availability of high performance computing resources have made it possible to perform optimization of multi-parameter designs, even when the latter require longer computational times (for example simulations of particle interactions with matter). Procedures involving machine-assisted techniques used to inform the design decision have seen a considerable growth in popularity among the EIC detector community. Having already been realized for tracking and RICH PID detectors, it has a potential application in calorimetry designs. A …

The Effects Of Environmental Factors On Tsunami Propagation And Inundation: A Comparison Of Earth With Other Planetary Bodies, Austin Halstead

All Master's Theses

Tsunamis are a universal hazard in any environment with oceans or lakes. Having a firm understanding of them is essential because of this. However, the vast number of tsunami studies have been solely on Earth, despite the growing evidence of oceans and lakes being on, or having once existed on, other planets and moons. In this study, I investigated tsunami behavior in non-Earth environments by testing the effects of varying viscosity and gravity. I conducted simulations using GeoClaw, Flow3D®, and VolcFlow on established tsunami benchmarks to identify consistent patterns in tsunami flow patterns and inundation. The results show …

Many Extensions Of Coulomb’S Law: A Scoping Review, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this paper, Coulomb’s Law is extended from two stationary charged particles, on linear trajectory, to: many charged particles, or quantum level particles, or objects on arbitrary motions (with velocity, acceleration, time delay), on non-linear trajectories, at even superluminal and instantaneous speeds.

Unveiling Quantum Communication: From Bell's Inequality To Neutrosophic Logic, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this mini-review, we delve into the intriguing realm of quantum communication, spurred by China's recent development of the Tiantong communication satellite. This satellite, shrouded in secrecy, hints at a revolutionary approach to communication that transcends the limitations of conventional signal transmission. We explore the foundational concepts of Bell's inequality and neutrosophic logic, elucidating their roles in understanding the non-local phenomena of quantum entanglement and its potential for secure and rapid communication. Additionally, we examine the connection between Bell's inequality and Shannon information entropy, unveiling the intricate relationship between quantum mechanics and information theory. Through this exploration, we glimpse a …

Possible Evidences For Existence Of An Aether Medium (Or Virtual Inertia/Spin Superfluid Medium), Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The presentation explores the possibility of an aether medium, also referred to as a virtual inertia/spin superfluid medium, existing to explain certain physical phenomena. While the concept of an aether has been historically rejected by mainstream physics, recent findings and interpretations offer potential justifications for its reconsideration. After discussions with several physicists, notably Robert N. Boyd, PhD and others, we are convinced that aether medium does exist, or may be called virtual inertia/spin superfluid medium.

The Present And Future Of Qcd, P. Achenbach, D. Adhikari, A. Afanasev, F. Afzal, C. A. Aidala, A. Al-Bataineh, D. K. Almaalol, M. Amaryan, D. Androić, W. R. Armstrong, M. Arratia, J. Arrington, A. Asaturyan, E. C. Aschenauer, H. Atac, H. Avakian, T. Averett, C. Ayerbe Gayoso, X. Bai, M. Zurek, Et. Al.

Physics Faculty Publications

This White Paper presents an overview of the current status and future perspective of QCD research, based on the community inputs and scientific conclusions from the 2022 Hot and Cold QCD Town Meeting. We present the progress made in the last decade toward a deep understanding of both the fundamental structure of the sub-atomic matter of nucleon and nucleus in cold QCD, and the hot QCD matter in heavy ion collisions. We identify key questions of QCD research and plausible paths to obtaining answers to those questions in the near future, hence defining priorities of our research over the coming …

Hubble Tension And Gravitational Self-Interaction, Corey Sargent, William Clark, Alexander Deur, Balša Terzić

Physics Faculty Publications

One of the most important problems vexing the ΛCDM cosmological model is the Hubble tension. It arises from the fact that measurements of the present value of the Hubble parameter performed with low-redshift quantities, e.g. the Type IA supernova, tend to yield larger values than measurements from quantities originating at high-redshift, e.g. fits of cosmic microwave background radiation. It is becoming likely that the discrepancy, currently standing at 5σ, is not due to systematic errors in the measurements. Here we explore whether the self-interaction of gravitational fields in General Relativity, which are traditionally neglected when studying the evolution …

Fully Relativistic Derivation Of The Thermal Sunyaev-Zel'dovich Effect, Balša Terzić, Geoffrey A. Krafft, William Clark, Alexandre Deur, Emerson Rogers, Ioannis Sakiotis, Brandon Velasco

Physics Faculty Publications

We present the first fully and inherently relativistic derivation of the thermal Sunyaev-Zel'dovich effect. This work uses the formalism historically applied to compute radiation spectra emerging from inverse Thomson/Compton sources of x-ray radiation. Comparing our results to the traditional approach based on relativistically-corrected classical Kompaneets equation, we find small, but systematic differences. Most notable are the modest (⩽10%) differences in the crossover frequency where the spectral distortion due to the Sunyaev-Zel'dovich effect vanishes, and the quadratic scaling of the energy shift with the electron cloud temperatures.

Molecules In Cool Stars: The A²Π - X²Σ⁺ And The B²Σ⁺ And The B²Σ⁺ - X²Σ⁺ Band Systems Of Cacl, Léo Lavy, Peter F. Bernath

Chemistry & Biochemistry Faculty Publications

Cool red giant stars exhibit absorption bands of calcium monochloride (CaCl) in the optical region. In this work, the bands of CaCl corresponding to the A²Π − X²Σ⁺ transition with v′ ≤ 4 and v″ ≤ 4, and B²Σ⁺ − X²Σ⁺ transition with v′≤ 2 and v″ ≤ 2 are rotationally analyzed with PGOPHER, a multipurpose program for simulating and fitting molecular spectra. All bands were analyzed using high-resolution absorption spectra collected at the National Solar Observatory in 1985, calibrated with atomic lines from a high-resolution emission spectrum obtained …

Searching For Black Holes In The Galactic Center, Caden Zaccardi

Honors Undergraduate Theses

Due to the high extinction along the plane of the Milky Way towards the Galactic Center (GC), it is useful to look at objects that are bright in the near-infrared (near-IR) to obtain data with Earth-based instruments. To identify X-ray Binary (XRB) counterparts towards the GC, we used near-IR spectra from the Large Binocular Telescope (LBT). After reducing the LUCI/LBT spectra with the superFATBOY (sFB) pipeline, we compared our near-IR spectra to previously matched IR and X-ray sources in the GC (DeWitt, 2011). Particularly, we looked for H and He emission lines, which indicate signs of a hard radiation field …

Refracting Ufos: Solutions For Fermi Questions, May 2024, John Adam

Mathematics & Statistics Faculty Publications

This article, titled "Refracting UFOs: Solutions for Fermi Questions, May 2024," recounts the author's personal experience as a teenager observing a UFO sighting near their home in England. The author used their telescope to observe the object, which turned out to be lights from a distant airplane flying in a circular holding pattern. The article then presents two questions related to the observed phenomenon, including estimating the diameter of the aircraft's path and the banking angle of the aircraft at its speed. The article concludes with a solution to estimating the distance to the aircraft. The information is presented objectively …

Refracting Ufos, John Adam

Mathematics & Statistics Faculty Publications

Question 2: Assuming θ ≈ 2° = π/90 rad, estimate the distance R to the aircraft. Assume that R ≫ d. Question 1: Suppose that the observed “period of oscillation” is 1 min, and the speed of the aircraft is 200 km/h. Estimate the diameter d of the aircraft path (assuming that it is circular). Estimate the banking angle of the aircraft at this speed. While still a teenager (and aspiring astronomer), I became interested in the subject of UFOs (more appropriately named UAPs—see Ref. 1). The region in which I lived (50 km west of London) was in the …

Latent Space Dynamics Learning For Stiff Collisional-Radiative Models, Xuping Xie, Qi Tang, Xianzhu Tang

Mathematics & Statistics Faculty Publications

In this work, we propose a data-driven method to discover the latent space and learn the corresponding latent dynamics for a collisional-radiative (CR) model in radiative plasma simulations. The CR model, consisting of high-dimensional stiff ordinary differential equations, must be solved at each grid point in the configuration space, leading to significant computational costs in plasma simulations. Our method employs a physics-assisted autoencoder to extract a low-dimensional latent representation of the original CR system. A flow map neural network is then used to learn the latent dynamics. Once trained, the reduced surrogate model predicts the entire latent dynamics given only …

An Observational Census Of Post-Merger Galaxies And Supermassive Black Hole Pair Evolution, Gregory Walsh

Graduate Theses, Dissertations, and Problem Reports (ETD)

Massive galaxy mergers are a fundamental consequence of the dynamic evolution of the Universe and play a central role in the evolution of galaxies. Because all massive galaxies harbor a central supermassive black hole (SMBH; M ≥ 10⁶ M_⊙), studying these merging systems with electromagnetic (EM) techniques constrains galaxy evolution models and provides a systematic means to examine the astrophysical mechanisms that facilitate the growth of SMBHs. These growing SMBHs are observable across the EM spectrum as Active Galactic Nuclei (AGN). Massive galaxy mergers are a natural formation mechanism for an SMBH pair, eventually evolving into an …

Alfred Russel Wallace Notes 29. Extraterrestrial Entertainment: Are We Being Monitored By Alien Beings?, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (1823−1913) was an early advocate for the rational assessment of likelihood of extraterrestrial life. Current efforts to evaluate the situation have ranged from the heavily self-indulgent to the more objective, and it is still often difficult to decide just how much of the information we are receiving on the subject is dependable. An attempt is made here to cut through the haze and reduce the matter to elementals.

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 …

The A²Π–X²Σ⁺ Band System Of Yo, Peter F. Bernath, Manish Bhusal, Adam Pastorek

Chemistry & Biochemistry Faculty Publications

YO bands are conspicuous in the spectra of S stars. The laboratory spectrum of the A²Π–X²Σ⁺ electronic transition has been recorded with a Fourier transform spectrometer using a composite-wall hollow cathode lamp source. The A²Π–X²Σ⁺ transition with v ' ≤ 4 and v'' ≤ 4 has been rotationally analyzed using the modern spectral fitting program PGOPHER. Vibronic band strengths were calculated using an ab initio transition dipole moment function. A line list for the A²Π–X²Σ⁺ transition is provided and can be utilized in the modeling …

Visible Opacities Of S-Type Stars: The D³Φ–A³Δ Band System Of Zro, Peter F. Bernath, Manish Bhusal, Jacques Liévin

Chemistry & Biochemistry Faculty Publications

ZrO is a well-studied metal monoxide because of its astrophysical importance in characterizing S stars. The bands of the d³Φ–a³Δ system (γ system) with v′≤4 and v" ≤ 5 are rotationally analyzed using the PGOPHER program to provide spectroscopic constants. The high-resolution ZrO emission spectrum was recorded with a Fourier transform spectrometer using a high-temperature carbon furnace source. New ab initio calculations of the transition dipole moment were carried out in order to determine the vibronic band strengths. The spectroscopic constants, along with the band strengths, are used to calculate a line list for the γ system. This line list …

Opacities Of S-Type Stars: The Singlet B¹⊓−X¹Σ⁺, B¹⊓−A¹Δ, And C¹Σ⁺−X¹Σ⁺ Band Systems Of Zro, Peter F. Bernath, Manish Bhusal, Jacques Liévin

Chemistry & Biochemistry Faculty Publications

The ZrO B¹Π–X¹Σ⁺, B¹Π–A¹Δ, and C¹Σ+–X¹Σ⁺ band systems are important opacity sources in the near-infrared and optical spectra of S-type stars. A total of 21 rovibronic bands with v'' ≤ 7 and v' ⩽ 5 were observed and fit for the B¹Π–X¹Σ⁺ transition, five bands for the ⁹⁰ZrO B¹Π–A¹Δ transition and one band for the ⁹⁰ZrO C¹Σ⁺–X¹Σ⁺ transition. All band …

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.

Exploring The Hot And Gaseous Universe From Infrared To X-Ray, Chamani Gunasekera

Theses and Dissertations--Physics and Astronomy

Over 90% of baryonic matter in the universe exists as astrophysical plasmas. The gas
is often far from thermodynamic equilibrium, so numerical non-equilibrium spectral
synthesis simulations are used to understand observations. cloudy simulates vari-
ous physical conditions, providing spectra predictions. This thesis aims to meet the
challenge of new observatories like the JWST (James Webb Space Telescope) and
XRISM (X-Ray Imaging Spectroscopy Mission). These simulations are no better
than the underlying atomic and molecular database and the fourth chapter details
a long-needed update to an evolving database. The predicted spectra are strongly
affected by the composition of the gas, which …

Spinning Spheroidal Components Of Disk Galaxies: Resonant Interactions With Stellar Bars, Xingchen Li

Theses and Dissertations--Physics and Astronomy

The majority of disk galaxies possess stellar bars, which are the main driver in the internal evolution of barred galaxies. Bars represent non-axisymmetric perturbations in the galactic disks, producing strong gravitational torques that facilitate angular momentum transfer from the disk to the spheroidal components, such as central stellar bulges and host dark matter (DM) halos. The redistribution of angular momentum in barred galaxies proceeds mainly via resonant interactions between the bar and orbits in the spheroids. The amount of angular momentum emitted or absorbed at each resonance depends on the mass distribution, density and spin in the spheroidal components. Thus, …

A Multi-Wavelength Determination Of The Total Luminosity And Star Formation Rate Of The Milky Way, Joshua L. Mascoop

Graduate Theses, Dissertations, and Problem Reports (ETD)

The star formation rate (SFR) of the Milky Way is poorly understood in comparison to the SFR of other galaxies. In order to better find the Galaxy's place in the universe, it is imperative to understand the star formation activity occurring within it. We characterize the Galactic \hii\ region luminosity function (LF) at multiple infrared and radio wavelengths using a sample of 797 first Galactic quadrant \hii regions compiled from the WISE Catalog of Galactic \hii Regions. This sample is statistically complete for all regions powered by single stars of type O9.5V and earlier.

We find that neither a single …