Physics Commons^™

The Pierre Auger Observatory Open Data, M. Zavrtanik, D. Zavrtanik, E. Zas, O. Zapparrata, A. Yushkov, B. Yue, B. Fick, K. Nguyen, D. Nitz, Et Al.

Michigan Tech Publications

The Pierre Auger Collaboration has embraced the concept of open access to their research data since its foundation, with the aim of giving access to the widest possible community. A gradual process of release began as early as 2007 when 1% of the cosmic-ray data was made public, along with 100% of the space-weather information. In February 2021, a portal was released containing 10% of cosmic-ray data collected by the Pierre Auger Observatory from 2004 to 2018, during the first phase of operation of the Observatory. The Open Data Portal includes detailed documentation about the detection and reconstruction procedures, analysis …

Deep Learning-Based Superconductivity Prediction And Experimental Tests, Daniel Kaplan, Adam Zheng, Joanna Blawat, Rongying Jin, Robert J. Cava, Viktor Oudovenko, Gabriel Kotliar, Anirvan M. Sengupta, Weiwei Xie

Faculty Publications

The discovery of novel superconducting materials is a long-standing challenge in materials science, with a wealth of potential for applications in energy, transportation and computing. Recent advances in artificial intelligence (AI) have enabled expediting the search for new materials by efficiently utilizing vast materials databases. In this study, we developed an approach based on deep learning (DL) to predict new superconducting materials. We have synthesized a compound derived from our DL network and confirmed its superconducting properties in agreement with our prediction. Our approach is also compared to previous work based on random forests (RFs). In particular, RFs require knowledge …

Optimal Reconstruction Of The Hellings And Downs Correlation, Bruce Allen, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) detect gravitational waves (GWs) via the correlations they create in the arrival times of pulses from different pulsars. The mean correlation, a function of the angle between the directions to two pulsars, was predicted in 1983 by Hellings and Downs (HD). Observation of this angular pattern is crucial evidence that GWs are present, so PTAs “reconstruct the HD curve” by estimating the correlation using pulsar pairs separated by similar angles. Several studies have examined the amount by which this curve is expected to differ from the HD mean. The variance arises because (a) a finite set …

A Sensitivity Analysis Of The Modeling Of Polycyclic Aromatic Hydrocarbon Emission In Galaxies, A. Maragkoudakis, C. Boersma, P. Temi, J. D. Bregman, L. J. Allamandola, Vincent J. Esposito, A. Ricca, E. Peeters

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We have conducted a sensitivity analysis on the mid-infrared spectral decomposition of galaxies and the modeling of the polycyclic aromatic hydrocarbon (PAH) emission spectrum with the NASA Ames PAH Infrared Spectroscopic Database (PAHdb) to assess the variance on the average galaxy PAH population properties under a grid of different modeling parameters. We find that the short-low and short-low+long-low Spitzer-IRS decomposition with PAHFIT provides consistent modeling and recovery of the 5–15 μm PAH emission spectrum. For PAHdb modeling, application of a redshift to the calculated spectra to account for anharmonic effects introduces a 15%–20% variance on the derived parameters, while its …

Computational Investigation Of The Unveils Nsd2 Inhibition Potential Of Berberis Vulgaris, Sambucus Nigra, And Morus Alba Through Virtual Screening, Molecular Docking, Md Simulation, And Dft Analyses, Supriyo Saha, Vanshita Gupta, Ahad Hossain, Prinsa Prinsa, Jannatul Ferdous, Kiran Bharat Lokhande, Vikash Jakhmola, Sarkar M. A. Kawsar

Karbala International Journal of Modern Science

Nuclear receptor binding set domain protein 2 (NSD2) plays a key role in chromatin regulation and is associated with different cancers and other developmental problems. Berries are rich in major secondary metabolites with anticancer properties. Here, we virtually screened 145 berry phytochemicals as putative NSD2 inhibitors via structure-based virtual screening, molecular docking, MD simulations, and DFT and ADMET analyses. Among them, α-carotene had the maximum docking score of -9.9 kcal/mol, followed by sulfuretin and β-amyrin. MD simulation analysis revealed that the dynamic behavior of the ligand‒NSD2 complexes was within the limit, indicating no significant changes in the structural integrity of …

Novel Approach For The Micro Cracks Detection Of Solar Wafers And Cells, Mohd Israil, Arvind Kumar Sharma, Ekta Gupta

Al-Bahir

This paper deals with the review of various existing technique for the microcracks detection in silicon solar cell and wafer. In addition to this, we proposed a novel approach for the machine learning technique for the inspection of the cracks those are existed in the solar cell and wafer and not able to detect by the naked eyes. There are many techniques have been developed by the various researchers around the world to inspect solar cells for defect. All the techniques discussed in this article having some features and some weakness too. This paper present here gives the two-fold solution …

Photolysis And Sublimation Chemistry Of Ammonium Cyanide With Relevance To Cometary Environments, O. H. Wilkins, K. M. Yocum, Vincent J. Esposito, E. Harel, S. N. Milam, P. A. Gerakines

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bulk nitrogen is depleted in solar system objects, including the terrestrial planets, chondritic meteorites, and comets. Recently, it was suggested that cometary nitrogen may be locked up in ammonium salts—ionic solids comprising ammonia (NH₃) and an acid such as hydrogen cyanide (HCN)—based on Rosetta/ROSINA data from comet 67P/Churyumov–Gerasimanko. Among the proposed salts to have been found in 67P were ammonium cyanide (NH₄CN) and ammonium cyanate (NH₄OCN), which were inferred from identifying HCN, cyanamide (NH₂CN), and isocyanic acid (HNCO) in the mass spectrometry data collected in the coma of 67P. However, the relationship …

Cryogenic Hybrid Magnonic Circuits Based On Spalled Yig Thin Films, Jing Xu, Connor Horn, Yu Jiang, Amin Pishehvar, Xinhao Li, Daniel Rosenmann, Xu Han, Miguel Levy, Supratik Guha, Xufeng Zhang

Michigan Tech Publications

Yttrium iron garnet (YIG) magnonics has garnered significant research interest because of the unique properties of magnons (quasiparticles of collective spin excitation) for signal processing. In particular, hybrid systems based on YIG magnonics show great promise for quantum information science due to their broad frequency tunability and strong compatibility with other platforms. However, their broad applications have been severely constrained by substantial microwave loss in the gadolinium gallium garnet (GGG) substrate at cryogenic temperatures. In this study, we demonstrate that YIG thin films can be spalled from YIG/GGG samples. Our approach is validated by measuring hybrid devices comprising superconducting resonators …

Gravity Tunnel Dynamics At Non-Zero Tunnel Diameters, Shafat Mubin, Walker T. Hayes

Georgia Journal of Science

A standard exercise in undergraduate mechanics derives the trajectory of a particle that has been dropped through a gravity tunnel passing through the center of the Earth as simple harmonic oscillation, assuming uniform earth density and negligible tunnel radius. We show that when the more accurate Preliminary Reference Earth Model (PREM) density profile and non-negligible tunnel radii are taken into consideration, significant deviations from harmonic oscillation are observed along with increasing or decreasing average particle speeds. Furthermore, we report that a particle traveling along a diameter perpendicular to the axis of the gravity tunnel is unable to reach the center …

Toward Alleviating The 𝐻₀ And 𝑆₈ Tensions With Early Dark Energy-Dark Matter Drag, T. Simon, T. Adi, J. L. Bernal, E. D. Kovetz, V. Poulin, Tristan L. Smith

Physics & Astronomy Faculty Works

Early dark energy, an additional component of dark energy active in the decade of redshift before recombination, has emerged as one of the most effective models at reducing the “𝐻₀ tension” between direct measurement of the Hubble parameter 𝐻₀ in the late Universe and the Λ CDM prediction when calibrated on Planck. However, it requires a slight increase in the dark matter density 𝜔_cdm and primordial tilt 𝑛_𝑠 that worsens the “𝑆₈ tension” between measurements of weak gravitational lensing at low redshifts and the Planck/Λ⁢CDM prediction. Using a phenomenological fluid model, we investigate whether the inclusion …

Spatial And Spectral Characterization Of The Gravitational-Wave Background With The Pta Optimal Statistic, Kyle A. Gersbach, Stephen R. Taylor, Patrick M. Meyers, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) have made tremendous progress and are now showing strong evidence for the gravitational-wave background (GWB). Further probing the origin and characteristics of the GWB will require more generalized analysis techniques. Bayesian methods are most often used but can be computationally expensive. On the other hand, frequentist methods, like the PTA optimal statistic (OS), are more computationally efficient and can produce results that are complementary to Bayesian methods, allowing for stronger statistical cases to be built from a confluence of different approaches. In this work we expand the capabilities of the OS through a technique we call …

Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang

Physics Faculty Research & Creative Works

A recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ≈0.8 PeV has made it the second confirmed "PeVatron" microquasar. Here we report on the observation of V4641 Sgr with X-Ray Imaging and Spectroscopy Mission (XRISM) in 2024 September. Thanks to the large field of view and low background, the CCD imager Xtend successfully detected for the first time X-ray extended emission around V4641 Sgr with a significance of ≳4.5σ and >10σ based on our imaging and spectral analysis, respectively. The spatial extent is estimated to have a radius of 7′ ± 3′ …

Detection Of Extended X-Ray Emission Around The Pevatron Microquasar V4641 Sgr With Xrism, Hiromasa Suzuki, Naomi Tsuji, Yoshiaki Kanemaru, Megumi Shidatsu, Laura Olivera-Nieto, Samar Safi-Harb, Shigeo S. Kimura, Eduardo De La Fuente, Sabrina Casanova, Kaya Mori, Xiaojie Wang, Sei Kato, Dai Tateishi, Hideki Uchiyama, Takaaki Tanaka, Hiroyuki Uchida, Shun Inoue, Dezhi Huang, Marianne Lemoine-Goumard, Daiki Miura, Shoji Ogawa, Shogo B. Kobayashi, Chris Done, Maxime Parra, Maria Díaz Trigo, Teo Muñoz-Darias, Montserrat Armas Padilla, Ryota Tomaru, Yoshihiro Ueda

Michigan Tech Publications

A recent report on the detection of very-high-energy gamma rays from V4641 Sagittarii (V4641 Sgr) up to ≈0.8 PeV has made it the second confirmed “PeVatron” microquasar. Here we report on the observation of V4641 Sgr with X-Ray Imaging and Spectroscopy Mission (XRISM) in 2024 September. Thanks to the large field of view and low background, the CCD imager Xtend successfully detected for the first time X-ray extended emission around V4641 Sgr with a significance of ≳4.5σ and >10σ based on our imaging and spectral analysis, respectively. The spatial extent is estimated to have a radius of 7′ ± 3′ …

Thermal Noise Measurement Below The Standard Quantum Limit, Ronald Pagano

LSU Doctoral Dissertations

Quantum mechanics places sensitivity restrictions on physical measurements. These limitations manifest themselves in interferometric force and displacement measurements as uncertainty both in the photon number measured at a photodetector (shot noise), and in the quantum radiation pressure applied to the interferometer (quantum back action noise manifested as quantum radiation pressure noise). The balance between shot noise and quantum radiation pressure noise imposes the Standard Quantum Limit (SQL). A large body of work has been dedicated to measuring these quantum effects and mitigating them. Owing to the inherently small scale at which quantum effects are visible, classical effects must be subverted …

Developing Real-Time, Online Beam Control Of Uhdr Irradiators To Facilitate Flash Translational Investigations, Austin M. Sloop

Dartmouth College Ph.D Dissertations

The field of radiation oncology seeks novel techniques to increase the therapeutic ratio to treat malignancies while minimizing damage and toxicities in healthy tissues. While it was observed that delivering therapeutic doses at high dose rate could elicit lower biological effects over a half-century ago, the field of ultra-high dose rate (UHDR) radiation therapy (colloquially known as FLASH RT) has seen a resurgence in recent years due to an alignment of accelerator capability, dosimetric advances, and improved biotechnological techniques. This has opened the door to studying potential underlying mechanisms such that we may leverage the effects of FLASH tissue sparing …

The Nanograv 15 Yr Data Set: Removing Pulsars One By One From The Pulsar Timing Array, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. Decesar

Pacific Faculty Work

Evidence has emerged for a stochastic signal correlated among 67 pulsars within the 15 yr pulsar-timing data set compiled by the NANOGrav collaboration. Similar signals have been found in data from the European, Indian, Parkes, and Chinese pulsar timing arrays. This signal has been interpreted as indicative of the presence of a nanohertz stochastic gravitational-wave background (GWB). To explore the internal consistency of this result, we investigate how the recovered signal strength changes as we remove the pulsars one by one from the data set. We calculate the signal strength using the (noise-marginalized) optimal statistic, a frequentist metric designed to …

Studying The Low-Lying Structure Of 9b Via The 10b(3he,A)9b Reaction, Rachel M. Shaffer

LSU Doctoral Dissertations

The unstable nature of ⁹B makes it a challenging isotope to study. The first-excited state of ⁹B has been particularly difficult to characterize. Since the first experimental observation of this state in 1955, many experimental and theoretical nuclear structure studies have sought to classify it, but with large discrepancies in the energy and width values from these results, the properties of the state remain inconclusive.

An experiment using the ¹⁰B(³He,α)⁹B reaction was performed at the John D. Fox Superconducting Linear Accelerator Laboratory at Florida State University in an effort to populate and characterize …

Baryon Number Violation Search, Tyler D. Stokes

LSU Doctoral Dissertations

Understanding the fundamental forces and symmetries of nature has long been a central goal of particle physics. While the Standard Model (SM) provides a successful framework, it does not guarantee the conservation of baryon number B or lepton number L, thus motivating searches for their violation. Proton decay, a fundamental process violating B, has been at the forefront of experimental searches for decades.

The discovery of the weak neutral current in 1973 unified the electromagnetic and weak forces and inspired the creation of Grand Unified Theories (GUTs) that also unify the strong force. In 1974, the first-ever GUT, …

Cloud Microphysical Response To Entrainment Of Dry Air Containing Aerosols, Jae Min Yeom, Hamed F. Sadi, Jesse Anderson, Fan Yang, Will Cantrell, Raymond Shaw

Michigan Tech Publications

Impacts of aerosol particles on clouds, precipitation, and climate remain one of the significant uncertainties in climate change. Aerosol particles entrained at cloud top and edge can affect cloud microphysical and macrophysical properties, but the process is still poorly understood. Here we investigate the cloud microphysical responses to the entrainment of aerosol-laden air in the Pi convection-cloud chamber. Results show that cloud droplet number concentration increases and mean radius of droplets decreases, which leads to narrower droplet size distribution and smaller relative dispersion. These behaviors are generally consistent with the scenario expected from the first aerosol-cloud indirect effect for a …

Impact Of Arctic And Antarctic Sudden Stratospheric Warmings On Thermospheric Composition, Jiarong Zhang, Jens Oberheide, Nicholas M. Pedatella, Guiping Liu

All Physics Faculty Publications

Using the Global‐scale Observations of the Limb and Disk (GOLD) and the Global Ultraviolet Imager (GUVI), we examine the impact of sudden stratospheric warmings (SSWs) on the changes of thermospheric composition during the 2018–2019 and 2020–2021 Arctic SSWs and the 2019 Antarctic SSW. Contributions of planetary waves, gravity waves, and migrating tides are assessed by performing numerical experiments with the NSF National Center for Atmospheric Research (NCAR) vertically extended version of the Whole Atmosphere Community Climate Model (WACCM‐X). The variations in the column integrated O and N2 density ratio (∑ O/N₂) are generally similar among WACCM‐X, GOLD, …

New Frontiers In Synthesis Of High-Entropy Materials Enabled By Microwave-Induced Plasma, Bria Christina Storr

All ETDs from UAB

This dissertation presents the novel approach for synthesizing high entropy borides (HEBs) and high entropy alloys (HEAs) using microwave-induced plasma as a rapid and efficient processing tool. High entropy materials (HEMs) have peaked interested in recent years due to their unique properties and practical applications such as thermal stability, and corrosion and wear resistance. HEMs are designed by combining multiple principal elements in near-equimolar ratios, enhancing stability, and offering a broad spectrum of tailored mechanical properties. The inclusion of multiple transition metals within these structures increases hardness and oxidation resistance, and the flexibility in element selection enables precise tuning for …

Evaluation Of Green Tea Yoghurt Enriched With Lacticaseibacillus Paracasei E1 Microcapsules On Macrophage M1 Profile In High Fat-Fructose Diet Mice, Esha Ardiansyah, Nur Alfi Maghfirotus Sa’Adah, Rahmi Izati, Belinda Nabiila Al Faizah, Dawama Nur Fadlilah, Septhyanti Aprilia Kavitarna, Mochammad Fitri Atho’Illah, Siti Nur Arifah, Yoga Dwi Jatmiko, Muhaimin Rifa’I

Karbala International Journal of Modern Science

Obesity is caused by an energy imbalance that increases chronic low-grade inflammation, including macrophage cell infiltration. Adipose tissue macrophages are polarized into pro-inflammatory macrophage type 1 (M1), secrete large amounts of pro-inflammatory cytokines, and activate transcription factors. Yoghurt with probiotics is popular at all ages for its health benefits and must be protected by microencapsulation. Green tea (Camellia sinensis L.) fortification provides yoghurt nutrients while improving its functional qualities and bioactivity. This study aimed to evaluate the effect of microencapsulation of Lacticaseibacillus paracasei E1 in green tea yoghurt (GTY) on the profile of M1 macrophages in mice fed a …

The Nanograv 15 Yr Data Set: Running Of The Spectral Index, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy G. Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. Decesar

Pacific Faculty Work

The NANOGrav 15 yr data provide compelling evidence for a stochastic gravitational-wave (GW) background at nanohertz frequencies. The simplest model-independent approach to characterizing the frequency spectrum of this signal consists of a simple power-law fit involving two parameters: an amplitude A and a spectral index γ. In this Letter, we consider the next logical step beyond this minimal spectral model, allowing for a running (i.e., logarithmic frequency dependence) of the spectral index, grun (f ) = g + b ln (f /fref ). We fit this running-power-law (RPL) model to the NANOGrav 15 yr data and perform a Bayesian model …

Elastomeric Nanocomposite With Solvent-Free, One Step, In Situ Shear Exfoliation Of Graphite To Graphene, Ashiqur Rahman, Md Abdur Rahman Bin Abdus Salam, Matthew G. Boebinger, Ahmed Touhami, Jennifer Lynch, Ali Ashraf

Physics & Astronomy Faculty Publications

A graphene nanoflake (GNF)-enhanced elastomeric nanocomposite (G-EMC) is fabricated following an innovative, cost-effective, single-step, in situ shear exfoliation (ISE) method from low-cost bulk material, graphite, where uniform mixing happens simultaneously within the elastomer matrix. Electron microscopy, atomic force microscopy, and photo-induced force microscopy results show good dispersion of GNFs with exfoliation to a few layers and uniform distribution in the elastomer matrix. X-ray photoelectron spectroscopy analysis shows less than 1% oxygen-containing functional groups/impurity, enhanced bonding through the formation of edge sites as fracture occurs across the GNF basal plane, and pi-pi interactions with newly exfoliated planar basal plane surfaces of …

A Second Candidate Magnetic Helium Core White Dwarf And 3 Other Variable White Dwarfs In The Globular Cluster Ngc 6397, Manuel Pichardo Marcano, Liliana E. Rivera Sandoval, Thomas J. Maccarone, Rene D. Rohrmann, Leandro G. Althaus, Craig O. Heinke, Diogo Belloni, Arash Bahramian

Physics & Astronomy Faculty Publications

Using archival Hubble Space Telescope observations, we report the discovery of four variable low-mass white dwarfs (WDs; 0.18 M⊙ ≤ M ≤ 0.5 M⊙) in the globular cluster NGC 6397. One source exhibits a periodic optical modulation of 5.21 ± 0.02 hr, which we interpret as potentially due to the rotation of a magnetic helium core WD (He WD). This makes this candidate the second magnetic He WD in NGC 6397, and one of the few He WDs with a measured rotation period. The other three candidates show aperiodic variability, with a change in magnitude ranging from ∼0.11 …

Data Supporting "Cloud Microphysical Response To Entrainment Of Dry Air Containing Aerosols", Will Cantrell, Jae Min Yeom, Hamed F. Sadi, Jesse Anderson, Fan Yang, Raymond Shaw

Michigan Tech Research Data

Aerosol particles play a pivotal role in shaping clouds, precipitation, and climate. However, it still remains one of the significant uncertainties in climate change. While most aerosols are activated at the cloud base, the aerosol particles entrained from the cloud top or edges can also contribute to droplet formation above the base. This process might significantly impact cloud properties and lifetimes.

In this study, we investigate how entraining aerosol-laden air affects cloud microphysics by adding aerosol particles to the dry-air inflow in the Pi chamber experiments. The findings show that the cloud droplet number concentration and liquid water content increase …

Development And Characterization Of Sodium Alginate-Based Active Edible Films Functionalized With Olive Mill Wastewater Extract, Nassima Hadri, Mohamed Didi Ould El-Hadj, Zineb Mahcene, Fatih Bozkurt, Rusen Metin Yildirim, Youcef Rahmani, Aicha Tedjani, Muhammet Arici

Karbala International Journal of Modern Science

Phenolic compounds from olive mill wastewater (PCO) of Algerian origin were used to produce sodium alginate-based active films using the casting method. The effects of adding various concentrations of PCO (0%, 0.1%, and 0.2% w/v) were evaluated regarding the molecular, morphological, thermal, physicochemical, optical, barrier, biodegradability, antimicrobial, and antioxidant properties of the alginate films. The FTIR and SEM results elucidated the development of a coherent cross-linked structure attributed to hydrogen bonding interactions between PCO and alginate chains. Consequently, the films exhibited enhanced crystallinity and thermal stability, as revealed by DSC analysis. Moreover, PCO addition positively influenced several film properties, including …

Deriving The Efficiency Of Electron Acceleration Within Current Sheets In The May 8th, 2021 Solar Flare Using A Centroid Analysis Method On Stix X-Ray Data, Isaiah Beauchamp

Masters Theses & Specialist Projects

Solar flares are powerful explosions that take place on the Sun, equivalent to a billion atomic bombs, and eject billions of tons of material into space. Flares that reach Earth can disrupt power grids and damage satellite communication systems, presenting challenges for our national security. Studying solar flares is crucial to better understand and prepare for these events.

During a solar flare, electrons are accelerated into the surrounding plasma. The interaction between electrons and heavier particles within the plasma causes the emission of powerful X-rays. Studying X-rays from solar flares can, therefore, provide insight into the accelerated electrons that produce …

Energy Dependence Of Polarized Γγ → E+E− In Peripheral Au + Au Collisions At √Snn = 54.4 And 200 Gev With The Star Experiment At Rhic, Star Collaboration

Physics and Astronomy Faculty Publications

We report the differential yields at mid-rapidity of the Breit-Wheeler process (γ γ → e+e−) in peripheral Au + Au collisions at √s NN = 54.4 and 200 GeV with the STAR experiment at the Relativistic Heavy Ion Collider (RHIC), as a function of energy √s NN , e+e− transverse momentum pT , p2 T , invariant mass Mee, and azimuthal angle. In the invariant mass range of 0.4 < Mee < 2.6 GeV/c2 at low transverse momentum (pT < 0.15 GeV/c), the yields increase while the pair √〈p2 T〉 decreases with increasing √s NN , a feature that is correctly predicted by the QED calculation. The energy dependencies of the measured quantities are sensitive to the nuclear form factor, infrared divergence and photon polarization. The data are compiled and used to extract the charge radius of the Au nucleus.

The Implosion Of The Titan Submersible: A Stress–Strain Experiment, Gregory A. Dilisi, Steven J. Eppell, Richard A. Rarick

2025 Faculty Bibliography

No abstract provided.