Open Access. Powered by Scholars. Published by Universities.®

Astrophysics and Astronomy Commons™

Open Access. Powered by Scholars. Published by Universities.®

8,856 Full-Text Articles 23,808 Authors 2,672,995 Downloads 207 Institutions

All Articles in Astrophysics and Astronomy

Faceted Search

8,856 full-text articles. Page 11 of 309.

Passages: The Discovery Of A Strongly Lensed Protocluster Core Candidate At Cosmic Noon, Nicholas Foo, Kevin C. Harrington, Brenda L. Frye, Patrick S. Kamieneski, Min S. Yun, Massimo Pascale, Ilsang Yoon, Allison Noble, Rogier A. Windhorst, Seth H. Cohen, James Lowenthal, Melanie Kaasinen, Belén Alcalde Pampliega, Daizhong Liu, Olivia Cooper, Carlos Garcia Diaz, Anastasio Diaz-Sanchez, Jose Diego, Nikhil Garuda, Eric F. Jiménez-Andrade, Reagen Leimbach, Amit Vishwas, Q. Daniel Wang, Dazhi Zhou, Adi Zitrin 2025 Arizona State University

Passages: The Discovery Of A Strongly Lensed Protocluster Core Candidate At Cosmic Noon, Nicholas Foo, Kevin C. Harrington, Brenda L. Frye, Patrick S. Kamieneski, Min S. Yun, Massimo Pascale, Ilsang Yoon, Allison Noble, Rogier A. Windhorst, Seth H. Cohen, James Lowenthal, Melanie Kaasinen, Belén Alcalde Pampliega, Daizhong Liu, Olivia Cooper, Carlos Garcia Diaz, Anastasio Diaz-Sanchez, Jose Diego, Nikhil Garuda, Eric F. Jiménez-Andrade, Reagen Leimbach, Amit Vishwas, Q. Daniel Wang, Dazhi Zhou, Adi Zitrin

Astronomy: Faculty Publications

Investigating the processes by which galaxies rapidly build up their stellar mass during the peak of their star formation (z  =  2–3) is crucial to advancing our understanding of the assembly of large-scale structures. We report the discovery of one of the most gas- and dust-rich protocluster core candidates, PJ0846+15 (J0846), from the Planck All-Sky Survey to Analyze Gravitationally lensed Extreme Starbursts (PASSAGES) sample. The exceedingly high total star formation rate (SFR) uncorrected for lensing magnification ( μ) of  μSFR  yr−1 is the result of a foreground cluster lensing at least 11 dusty star-forming galaxies between z …


A Study On The Great Comet Of 2024: C/2023 A3 (Tsuchinshan–Atlas) Via Radio Interferometry, Jesse Bier, Nathan X. Roth 2025 University of Missouri-St. Louis

A Study On The Great Comet Of 2024: C/2023 A3 (Tsuchinshan–Atlas) Via Radio Interferometry, Jesse Bier, Nathan X. Roth

Undergraduate Research Symposium

Our solar system is approximately 4.5 billion years old. Comets are remnants of its formation, serving as time capsules to give us an understanding of its natal heritage. Revealing our own solar system’s history allows us to gain insights into other young stellar systems and the potential for life elsewhere. C/2023 A3 (Tsuchinshan–ATLAS) was a comet from the Oort cloud on its first and possibly only journey to the inner solar system. The comet grew in brightness until it was brighter than Venus on October 9th, 2024, making it temporarily brighter than Venus and one of the brightest …


Education In The Planetarium: A Practical Approach, Matthew Fyfe 2025 Bowling Green State University

Education In The Planetarium: A Practical Approach, Matthew Fyfe

Honors Projects

This project proposes live planetarium programming built within the 5E instructional model. It creates a practical application of this with lesson modules surrounding topics in observational astronomy. Specifically, there are investigations into instrumentation through CCD cameras and data collection and processing through spectroscopy and photometry with light curve folding with activities highlighting each. Each module is broken down into segments corresponding to the learning cycles of the 5E model, and as they are self contained in this way can be used piecemeal in different combinations.


Gwtc-4.0: An Introduction To Version 4.0 Of The Gravitational-Wave Transient Catalog, A. G. Abac, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang 2025 The University of Texas Rio Grande Valley

Gwtc-4.0: An Introduction To Version 4.0 Of The Gravitational-Wave Transient Catalog, A. G. Abac, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

The Gravitational-Wave Transient Catalog (GWTC) is a collection of short-duration (transient) gravitational-wave signals identified by the LIGO–Virgo–KAGRA Collaboration in gravitational-wave data produced by the eponymous detectors. The catalog provides information about the identified candidates, such as the arrival time and amplitude of the signal and properties of the signal’s source as inferred from the observational data. GWTC is the data release of this dataset, and version 4.0 extends the catalog to include observations made during the first part of the fourth LIGO–Virgo–KAGRA observing run up until 2024 January 31. This Letter marks an introduction to a collection of articles related …


Facility Usage On The International Space Station, Justin St. P. Walsh, Rao Hamza Ali, Ryan Shihabi, Erik Linstead 2025 Chapman University

Facility Usage On The International Space Station, Justin St. P. Walsh, Rao Hamza Ali, Ryan Shihabi, Erik Linstead

Art Faculty Articles and Research

Science experiments on the International Space Station (ISS) and in future space habitats require “facilities,” as they are known to space agencies, as the core building blocks of the research capabilities they provide. Facilities are experimental apparatus that enable research, often (but not always) used for more than one experiment, such as centrifuges, furnaces, gloveboxes, freezers, and more. The US Orbital Segment of the ISS has been home to 191 such facilities, belonging to four of the five ISS international partner agencies as well as private companies, in its 25 years of continuous operation. Until now, there has been no …


The Influence Of Tight Binaries On Protoplanetary Disk Masses, K. Flaherty, P. Knowlton, T. Smith-Gandy, A. M. Hughes, M. Kounkel, Eric L.N. Jensen, J. Muzerolle, K. Covey 2025 Swarthmore College

The Influence Of Tight Binaries On Protoplanetary Disk Masses, K. Flaherty, P. Knowlton, T. Smith-Gandy, A. M. Hughes, M. Kounkel, Eric L.N. Jensen, J. Muzerolle, K. Covey

Physics & Astronomy Faculty Works

Binary systems are a common site of planet formation, despite the destructive effects of the binary on the disk. While surveys of planet-forming material have found diminished disk masses around binaries with medium separation (∼10–100 au), less is known about tight (< 10 au) binaries, where a significant circumbinary disk may escape the disruptive dynamical effects of the binary. We survey over 100 spectroscopic binaries in the Orion A region with the Atacama Large Millimeter/submillimeter Array (ALMA), detecting significant continuum emission among 21 of them with disk masses ranging from 1 to 100 M⊕. We find evidence of systematically lower disk masses among the binary sample when compared to single-star surveys, which may reflect a diminished planet-forming potential around tight binaries. The infrared excess fraction among the binary sample is comparable to that of single stars, although the tight binaries without significant ALMA emission display tentative evidence of weaker 3–5 …


Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger 2025 Missouri University of Science and Technology

Applications Of Machine Learning In Gravitational-Wave Research With Current Interferometric Detectors, Elena Cuoco, Marco Cavaglià, Ik Siong Heng, David Keitel, Christopher Messenger

Physics Faculty Research & Creative Works

This article provides an overview of the current state of machine learning in gravitational-wave research with interferometric detectors. Such applications are often still in their early days but have reached sufficient popularity to warrant an assessment of their impact across various domains, including detector studies, noise and signal simulations, and the detection and interpretation of astrophysical signals. In detector studies, machine learning could be useful to optimize instruments like LIGO, Virgo, KAGRA, and future detectors. Algorithms could predict and help in mitigating environmental disturbances in real time, ensuring detectors operate at peak performance. Furthermore, machine-learning tools for characterizing and cleaning …


Statistical Overview Of Long-Lived Active Regions Observed Across Multiple Carrington Rotations, Emily I. Mason, Kara L. Kniezewski 2025 Predictive Science Inc.

Statistical Overview Of Long-Lived Active Regions Observed Across Multiple Carrington Rotations, Emily I. Mason, Kara L. Kniezewski

Student Publications

The study of solar active regions (ARs) is of central importance to a range of fundamental science, as well as the practical applications of space weather. Active region emergence and life cycles are two areas of particular interest, yet the lack of consistent full-Sun observations has made long-term studies of active regions difficult. Here, we present results from a study to identify and characterize long-lived active regions (LLARs), defined as those which were observed during at least two consecutive Carrington rotations and which did not undergo significant successive flux emergence once the decay phase began. Such active regions accounted for …


Numerical Calculations Of The Electromagnetic And Gravitational Wave Signatures Of Unequal Mass Black Hole Binary Inspirals, Madeline Clyburn 2025 Clemson University

Numerical Calculations Of The Electromagnetic And Gravitational Wave Signatures Of Unequal Mass Black Hole Binary Inspirals, Madeline Clyburn

All Dissertations

In 2015, the Laser Interferometer Gravitational-Wave Observatory (LIGO) measured the first gravitational waves (GWs) from the coalescence of two stellar-mass black holes. This detection marked a historic milestone in astrophysics, confirming general relativity and establishing the existence of gravitationally bound black holes. Since then, researchers have extended the search to even more massive black hole mergers. Recently, the International Pulsar Timing Array (IPTA), including the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), detected a nanohertz GW background from supermassive black hole binaries (SMBHBs), black holes with masses M ≃10^7−10^9 M⊙ orbiting throughout the universe. However, a single SMBHB has …


Cosmic Duets: A Search For Binary Supermassive Black Holes In Merging Galaxies, Sagar Adhikari 2025 Clemson University

Cosmic Duets: A Search For Binary Supermassive Black Holes In Merging Galaxies, Sagar Adhikari

All Dissertations

Galaxies are vast cosmic islands of stars, dust, and gas. They come in various shapes and sizes. They might look static for the timescales we are used to, but they are dynamic and collisional systems that can merge with other galaxies to make bigger galaxies. Most galaxies, including the Milky Way, host a central supermassive black hole (SMBH) with a mass greater than a million (sometimes a billion) times the mass of the Sun. When galaxies merge, their SMBHs form a binary system before ultimately merging. These cosmic duets are of great interest to astronomers and astrophysicists as they are …


Characterizing Stellar Flares On Low-Mass Stars Tic 144217628 And Proxima Centauri Using Transiting Exoplanet Space Satellite (Tess) Optical Data, Charles Edward Holloway 2025 University of Arkansas-Fayetteville

Characterizing Stellar Flares On Low-Mass Stars Tic 144217628 And Proxima Centauri Using Transiting Exoplanet Space Satellite (Tess) Optical Data, Charles Edward Holloway

Graduate Theses and Dissertations

Low-mass stars account for more than 70% of stars within our galaxy. Their ob?servational interest can be attributed to their smaller radius and luminosity, making them ideal for detecting terrestrial planets inside their habitable zones. These magnetically active stars produce frequent stellar flaring events that can impact the atmospheric composition of nearby planets and interfere with the prebiotic processes for carbon-based life. Using TESS optical data, I have detected, measured astrophysical properties, and modeled the behavior of 44 flares from two low-mass stars: TIC 144217628 and Proxima Centuari. Given similar observational periods, Proxima Cen has shown to produce larger amplitudes …


Adsorption-Photodegradation Performance Of Silver Titanate For Methylene Blue Removal: Kinetics, Thermodynamics And Isotherm Studies, Nawrin Rahman Shefa, Most. Afroza Khatun, Ahmed Hasnain Jalal, M. Jasim Uddin, Md. Wasikur Rahman 2025 The University of Texas Rio Grande Valley

Adsorption-Photodegradation Performance Of Silver Titanate For Methylene Blue Removal: Kinetics, Thermodynamics And Isotherm Studies, Nawrin Rahman Shefa, Most. Afroza Khatun, Ahmed Hasnain Jalal, M. Jasim Uddin, Md. Wasikur Rahman

Physics & Astronomy Faculty Publications

Silver titanate (AgTO) was synthesized via an ion-exchange reaction between sodium titanate and silver nitrate. This study investigates the efficiency of AgTO in the combined adsorption-photodegradation process for removing Methylene Blue (MB). The synthesized material was characterized using FTIR, XRD, SEM, and EDX techniques. Batch adsorption experiments were conducted to assess the effects of AgTO dosage (0.1–1.0 g/L), initial MB concentration (5–20 mg/L), pH (3–11), and temperature (313–333 K). The highest MB removal efficiency (90 %) was achieved at 313 K, pH 3, and an initial MB concentration of 5 mg/L. The photocatalytic performance of AgTO was further evaluated under …


Stars And Shapes: An Investigation Of Stripped Envelope Supernovae Structures Using Spectropolarimetry Observations And Hydrodynamic Models, Sabrina DeSoto 2025 University of Denver

Stars And Shapes: An Investigation Of Stripped Envelope Supernovae Structures Using Spectropolarimetry Observations And Hydrodynamic Models, Sabrina Desoto

Electronic Theses and Dissertations

Supernovae (SNe) are the energetic deaths of massive stars, dispersing heavy elements throughout the galaxies and shaping cosmic evolution across the universe. However, understanding the connections between the evolution of massive stars, their catastrophic demises, and the myriad of observed SNe, remains a fundamental challenge in astrophysics. My work aims to narrow this gap by integrating extensive observational data with advanced hydrodynamical simulations to better interpret SNe observations and understand the origin of their geometry. The observational component utilizes the largest spectropolarimetry dataset of stripped-envelope (SE) core-collapse supernovae (CCSNe) gathered by the SNSPOL project. Analyzing nine Type Ib and eleven …


Converging On The Cepheid Metallicity Dependence: Implications Of Nonstandard Gaia Parallax Recalibration On Distance Measures, Louise Breuval, Gagandeep S. Anand, Richard I. Anderson, Rachael Beaton, Anupam Bhardwaj, Stefano Casertano, Gisella Clementini, Mauricio Cruz Reyes, Giulia De Somma, Lucas M. Macri 2025 The University of Texas Rio Grande Valley

Converging On The Cepheid Metallicity Dependence: Implications Of Nonstandard Gaia Parallax Recalibration On Distance Measures, Louise Breuval, Gagandeep S. Anand, Richard I. Anderson, Rachael Beaton, Anupam Bhardwaj, Stefano Casertano, Gisella Clementini, Mauricio Cruz Reyes, Giulia De Somma, Lucas M. Macri

Physics & Astronomy Faculty Publications

By comparing Cepheid brightnesses with geometric distance measures including Gaia EDR3 parallaxes, most recent analyses conclude metal-rich Cepheids are brighter, quantified as γ ∼ −0.2 mag dex−1 . While the value of γ has little impact on the determination of the Hubble constant in contemporary distance ladders (due to the similarity of metallicity across these ladders), γ plays a role in gauging the distances to metal-poor dwarf galaxies like the Magellanic Clouds and is of considerable interest in testing stellar models. Recently, B. F. Madore & W. L. Freedman (hereafter MF25) recalibrated Gaia EDR3 parallaxes by adding to them a …


The Odds Don’T Lie: Mathematical Reasoning And Societal Ignorance In Don’T Look Up, Nysa Vedwan, Shane Carey 2025 West Morris Central High School

The Odds Don’T Lie: Mathematical Reasoning And Societal Ignorance In Don’T Look Up, Nysa Vedwan, Shane Carey

LASER Journal

In Adam McKay’s 2021 satirical sci-fi movie Don’t Look Up, two astronomers discover a comet heading directly toward Earth. Despite overwhelming evidence and near-certainty of global extinction, their warnings are ignored and ridiculed. This paper discusses the mathematical and scientific foundations of the movie’s social and political reception, and specifically focuses on orbital prediction and probabilistic modeling as they relate to public understanding of risk. This paper shows how data is often undermined by political and social dynamics, by connecting the fictional events of the movie with real-world crises like the COVID-19 pandemic and the climate emergency. In Don’t Look …


Thermodynamic Feasibility Of Nanoenergetic Systems Based On Metal Oxynitrides, Manoj Chhetri, Mkhitar A. Hobosyan, Maxim Zyskin, Karen S. Martirosyan 2025 The University of Texas Rio Grande Valley

Thermodynamic Feasibility Of Nanoenergetic Systems Based On Metal Oxynitrides, Manoj Chhetri, Mkhitar A. Hobosyan, Maxim Zyskin, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

A comprehensive computational study was conducted to identify and evaluate nano-energetic systems utilizing aluminum (Al) as the fuel and a range of metal oxynitrides as oxidizers. The primary objective was to determine combinations that yield highly exothermic reactions, specifically those that maximize gas generation, adiabatic combustion temperature, and energy release. These parameters are critical for optimizing the performance of energetic materials in applications such as controlled energy delivery, propulsion, and pyrotechnics. By systematically analyzing thermodynamic properties including the heat of formation, enthalpy of reaction, Gibbs free energy, and equilibrium reaction products across a range of Al/oxynitride stoichiometries, the study aimed …


Likelihoods For Stochastic Gravitational Wave Background Data Analysis, Gabriele Franciolini, Mauro Pieroni, Angelo Ricciardone, Joseph D. Romano 2025 CERN

Likelihoods For Stochastic Gravitational Wave Background Data Analysis, Gabriele Franciolini, Mauro Pieroni, Angelo Ricciardone, Joseph D. Romano

Physics & Astronomy Faculty Publications

We present a systematic study of likelihood functions used for stochastic gravitational wave background (SGWB) searches. By dividing the data into many short segments, one customarily takes advantage of the central limit theorem to justify a Gaussian cross-correlation likelihood. We show, with a hierarchy of ever more realistic examples—beginning with a single frequency bin and one detector, and then moving to two and three detectors with white and colored signal and noise—that approximating the exact Whittle likelihood by various Gaussian alternatives can induce systematic biases in the estimation of the SGWB parameters. We derive several approximations for the full likelihood …


Experimental And Anharmonic Theoretical Spectroscopic Benchmarks Of Nitrogenated And Doubly-Nitrogenated Polycyclic Heterocycles, Selma Bejaoui, Brant E. Billinghurst, Christiaan Boersma, Vincent J. Esposito 2025 NASA Ames Research Center

Experimental And Anharmonic Theoretical Spectroscopic Benchmarks Of Nitrogenated And Doubly-Nitrogenated Polycyclic Heterocycles, Selma Bejaoui, Brant E. Billinghurst, Christiaan Boersma, Vincent J. Esposito

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

In this study, we report the first high-resolution gas-phase infrared absorption spectra and anharmonic vibrational simulations for three nitrogenated aromatic molecules, namely indole (C8H7N), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN; C7H12N2), and 1,8- diazabicyclo[5.4.0]undec-7-ene (DBU; C9H16N2) with excellent agreement between measurement and computation. Anharmonic cascade emission spectra (2–8 eV) of the three systems show that nitrogen substitution strongly modifies the emission spectra: indole reproduces the unidentified 3.3 μm emission in Titan’s atmosphere, while DBN and DBU exhibit redshifted aliphatic C–H stretches. In the 5–10 μm region, …


Determining The 17f(Α,P)20ne Reaction Rate For Application In Type I X-Ray Bursts, William Braverman 2025 Louisiana State University and Agricultural and Mechanical College

Determining The 17f(Α,P)20ne Reaction Rate For Application In Type I X-Ray Bursts, William Braverman

LSU Doctoral Dissertations

The 17F(α, p)20Ne reaction has been identified as an alternate pathway for breakout from the hot-CNO cycle that can be important in some X-ray burst scenarios. The 17F(α, p)20Ne reaction rate was previously determined through a parameterized exponential S-factor with a large enhancement from thermally-excited states based on statistical models with large uncertainties. We have measured the time-inverse 20Ne(p,α)17F cross section at center-of-mass energies ranging from 5.50 to 7.10 MeV using an activation method with a proton beam on a neon gas cell. Coincident detections of 511-keV γ-rays, resulting from electron-positron …


Gw241011 And Gw241110: Exploring Binary Formation And Fundamental Physics With Asymmetric, High-Spin Black Hole Coalescences, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, R. Espinosa, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang 2025 The University of Texas Rio Grande Valley

Gw241011 And Gw241110: Exploring Binary Formation And Fundamental Physics With Asymmetric, High-Spin Black Hole Coalescences, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, R. Espinosa, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang

Physics & Astronomy Faculty Publications

We report the observation of gravitational waves from two binary black hole coalescences during the fourth observing run of the LIGO–Virgo–KAGRA detector network, GW241011 and GW241110. The sources of these two signals are characterized by rapid and precisely measured primary spins, nonnegligible spin–orbit misalignment, and unequal mass ratios between their constituent black holes. These properties are characteristic of binaries in which the more massive object was itself formed from a previous binary black hole merger and suggest that the sources of GW241011 and GW241110 may have formed in dense stellar environments in which repeated mergers can take place. As the …


Digital Commons powered by bepress