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Articles 1 - 30 of 2944
Full-Text Articles in Astrophysics and Astronomy
Cedar: Investigating The Mesosphere And Lower Thermosphere Neutral Temperature And Winds Responses To Geomagnetic Storms Equatorward Of The Auroral Zone, Tao Yuan
Funded Research Records
No abstract provided.
Temperature Predictions With Zncuins/Zns Quantum Dots, Reu/Fri Program Physics And Astronomy, Amber Banks
Temperature Predictions With Zncuins/Zns Quantum Dots, Reu/Fri Program Physics And Astronomy, Amber Banks
Student Works
For hundreds of years, humans have built thermometers based on the principles of thermal expansion and contraction. In the modern world, there is a need to scale down our thermometers to monitor cellular reactions, both within the human body and within artificial organ chips. Lewis et al. (2020) introduces a nanoscale thermometer based on the thermal expansion of CdTe quantum dots. When ex panded, these dots exhibit systematic changes in photoluminescence (PL) which are recognized by a neural network as an increase in temperature. Our research builds upon the framework of Lewis et al. (2020), testing its feasibility with ZnCuInS/ZnS …
Characterization Of An Ambe Tagged Neutron Source For A 30-Ton Wbls Detector, Rylee Grover
Characterization Of An Ambe Tagged Neutron Source For A 30-Ton Wbls Detector, Rylee Grover
Discovery Day - Daytona Beach
Understanding the detection capabilities of water-based liquid scintillator (WbLS) is critical for its deployment in next-generation neutrino detectors such as THEIA and Phase II of the Deep Underground Neutrino Experiment (DUNE). This study focuses on the characterization and alignment testing of an Americium-Beryllium (AmBe) radioactive neutron source. We plan to dope the 30-ton WbLS detector at Brookhaven National Laboratory (BNL) with Gadolinium (Gd) to improve neutron detection capabilities. This will be tested by the implementation of an AmBe source as a calibration metric. The AmBe source emits neutrons coincident with a 4.4 MeV gamma ray, making it possible to perform …
M.O.D.U.S. Modular Optical Design Using Specular Film, Mario Gutierrez, Robert Thibodeau, Emma Show, Desiree Robinson, Lingyuan Meng, Sean Martin, Conner Beeson
M.O.D.U.S. Modular Optical Design Using Specular Film, Mario Gutierrez, Robert Thibodeau, Emma Show, Desiree Robinson, Lingyuan Meng, Sean Martin, Conner Beeson
Discovery Day - Daytona Beach
High-quality parabolic mirrors, which are vital components in reflecting telescopes, are typically bulky, costly, and highly fragile. This experiment explores the feasibility of using specular Class B Mylar as an unconventional, lightweight, and cost-effective alternative. This approach could enable new telescope designs by greatly reducing weight and manufacturing expenses, while also opening options for potential adaptability. This approach involves using Mylar, a flexible, reflective style of plastic. The mylar is formed into a concave mirror by stretching a sheet over a chamber and depressurizing one side to force the sheet into the necessary curved shape. Multiple designs are being created …
String-Of-Pearls Measurements Of Supersonic Plasma Jets Using Magnetospheric Multiscale Satellites, Amelia Koth
String-Of-Pearls Measurements Of Supersonic Plasma Jets Using Magnetospheric Multiscale Satellites, Amelia Koth
Discovery Day - Daytona Beach
High-energy supersonic plasma jets form when the solar wind, which is a flow of charged particles from the Sun, slows down as it encounters Earth’s magnetic shield. Occasionally, the solar wind remains at supersonic speeds as it enters this region. This forms plasma jets that propagate toward Earth; these jets can carry strong magnetic fields, drive magnetic reconnection, and potentially initiate substorms that lead to auroral activity. Previously studied plasma jets occurred when the interplanetary magnetic field (IMF) points southward. In contrast, this study focuses on northward IMF conditions, which are less understood, yet still capable of producing supersonic jets. …
Measuring Cosmic Expansion From Early To Late Times Using Quasars, Galaxies, & Local Supernovae, Rajeev Vaisakh
Measuring Cosmic Expansion From Early To Late Times Using Quasars, Galaxies, & Local Supernovae, Rajeev Vaisakh
Physics Theses and Dissertations
This dissertation investigates the evolution of cosmic expansion across a wide redshift ($z$) range by combining measurements from quasars \& galaxies in the distant universe $(z > 0.8)$ with those obtained from stripped-core collapse supernovae observations from the nearby universe $(z < 0.1)$. Using the DESI spectroscopic survey, we analyze large-scale clustering from quasars over $0.8 < z < 2.1$ and emission line galaxies over $0.8 < z < 1.6$, contributing to DESI DR2 BAO and full-shape measurements of cosmic expansion and structure growth. Combined with BBN in flat $\Lambda$CDM, DESI DR2 BAO gives $H_0 = 68.51 \pm 0.58$ km s$^{-1}$ Mpc$^{-1}$, while combinations of DESI BAO with CMB and supernova data show a preference for evolving dark energy, with representative constraints such as $w_0 = -0.752 \pm 0.057$ and $w_a = -0.86^{+0.23}_{-0.20}$ for DESI+CMB+DESY5. Using the ROTSE-III Supernova Survey and the expanding photosphere method (EPM), we measure distances to a sample of six supernovae for which the thermal phase can be clearly identified. This analysis focuses on testing whether reliable EPM distances can be obtained for this population. The resulting distances will eventually be compared with independent estimates from the literature. Establishing consistency with these external measurements represents an important step toward applying this methodology to larger samples, with the eventual goal of using ROTSE supernova distances to provide an independent measurement of the local Hubble constant.
Mining Time Series Shapelets And Association Rules For Solar Flare Prediction, Drew Watson
Mining Time Series Shapelets And Association Rules For Solar Flare Prediction, Drew Watson
All Graduate Theses and Dissertations, Fall 2023 to Present
Solar flares are the largest explosions in the solar system; they are caused by changes in the Sun’s magnetic field. Strong solar flares can disrupt power systems, damage satellites, and interfere with radio communication, so improving flare prediction is important. This thesis develops a way to predict severe solar flares while also helping researchers understand why those predictions are made. The approach looks for short patterns in solar magnetic field data that are linked to future flare activity. It then studies how these patterns appear together and in what order they happen over time. By doing this, the research not …
Emergent De Sitter Expansion And Closed Topology From The Cosmic Fabric Model As An Open Thermodynamic System: Resolving The Negative Bulk Modulus Paradox, T G. Tenev, C B. Ward, T F. Tenev, M F. Horstemeyer
Emergent De Sitter Expansion And Closed Topology From The Cosmic Fabric Model As An Open Thermodynamic System: Resolving The Negative Bulk Modulus Paradox, T G. Tenev, C B. Ward, T F. Tenev, M F. Horstemeyer
Faculty Publications and Presentations
The Cosmic Fabric Model establishes a continuum-mechanics isomorphism to General Relativity by representing physical space as an elastic three-dimensional hyperplate embedded in a four-dimensional spatial bulk. Reproducing vacuum kinematics requires a vanishing P-wave modulus, which in turn implies a negative bulk modulus—an apparent thermodynamic instability in a closed system. This paradox is resolved by recasting the framework as an open system: the instability is not pathological but instead drives cosmic expansion. In this interpretation, the observable universe is a lower-energy solid formed through continuous solidification from a higher-dimensional precursor fluid. Using multiplicative kinematics from finite-growth mechanics, the model shows that …
New Distance Distributions Of Asymptotic Giant Branch Stars And Their Role In Tracing Galactic Structure, Rajorshi Bhattacharya
New Distance Distributions Of Asymptotic Giant Branch Stars And Their Role In Tracing Galactic Structure, Rajorshi Bhattacharya
Physics & Astronomy ETDs
Asymptotic giant branch (AGB) stars are among the final evolutionary stages of low- and intermediate-mass stars and among the most luminous cool stellar populations in the Milky Way (MW). Their strong infrared emission allows them to be observed through regions of high interstellar extinction, making them useful tracers of the inner MW. However, their use is limited by unreliable distances because many are dust-obscured and variable, while geometric parallaxes are often unavailable or uncertain. This thesis develops statistical distance-estimation methods for large samples of oxygen-rich AGB stars. The resulting distances broadly agree with literature estimates, supporting their statistical reliability for …
Extending The Discovery Space Of Tess: Probing Underexplored Exoplanet Populations, Mallory L. Harris
Extending The Discovery Space Of Tess: Probing Underexplored Exoplanet Populations, Mallory L. Harris
Physics & Astronomy ETDs
This dissertation investigates how cold exoplanets can be identified despite the strong observational bias of exoplanet surveys toward short-period systems. Planets at wider orbital separations remain comparatively poorly constrained, limiting tests of planetary-system formation and the prevalence of outer architectures beyond compact systems. To address this gap, I use two complementary approaches. First, I develop a transit-search pipeline for TESS Full-Frame Images that identifies both isolated and repeated transit-like signals around nearby M dwarfs and characterizes the dominant false-positive classes that limit sensitivity in this regime. I then present TOI-904 c, the coldest planet discovered by TESS around an M …
An Investigation Of Tess M&Ms And The Occurrence Rate Of Transiting Circumbinary Planets, Dominic Oddo
An Investigation Of Tess M&Ms And The Occurrence Rate Of Transiting Circumbinary Planets, Dominic Oddo
Physics & Astronomy ETDs
Circumbinary planets (CBPs) are worlds which orbit two stars simultaneously. CBPs are excellent tests of the tenacity of planet formation, but are difficult to detect. The space-based NASA Transiting Exoplanet Survey Satellite (TESS) mission is a nearly all-sky survey designed to detect exoplanets transiting nearby stars. In this dissertation, I analyze the performance of TESS by comparing to the photometric precision of the ESA CHEOPS mission. Then, I define a catalog of low-mass eclipsing binaries (M&Ms), which are the best sources to search for CBPs. I describe my custom transit search methodology and apply it to the M&M catalog. I …
Quantum Control Of Qubits And Qudits In Neutral Atom Systems, Sri Datta Vikas Buchemmavari
Quantum Control Of Qubits And Qudits In Neutral Atom Systems, Sri Datta Vikas Buchemmavari
Physics & Astronomy ETDs
This dissertation explores control of neutral atom quantum systems across multiple levels of abstraction, from atomic physics to system-level fault tolerance, using optimal control to improve performance. First, we propose a Rydberg entangling gate based on dressing with only the qubit control field; an interaction energy near the Rabi frequency benefits both gate speed and Rydberg decay. Second, with Sandia National Laboratories, we show that leakage errors in neutral atom systems can be converted to atom loss errors and detected using two entangling gates with an auxiliary atom, where a SWAP-based leakage detection unit outperforms the standard design. Next, we …
Measurements And Studies For Rare Event Searches Using Directional Detectors, Elizabeth Tilly
Measurements And Studies For Rare Event Searches Using Directional Detectors, Elizabeth Tilly
Physics & Astronomy ETDs
Measuring topology and initial direction of low-energy (keV-MeV) particle tracks is interesting to rare-event searches. While directional dark matter searches have been one of the largest drivers for R&D for low-energy directional detectors, this work is interested in its application to Migdal searches. The Migdal effect—a nuclear recoil and an electron recoil sharing a vertex—has been used as a detection channel for low-mass dark matter but has only recently been measured. Low-energy directional detectors are ideal to measure the canonic Migdal topology. This dissertation discusses 3D reconstruction algorithms developed for the Migdal In Galactic Dark mAtter expLoration (MIGDAL) experiment and …
Exploring The Role Of A Mushy, Crustal Compliant Region In Volcano Deformation, Grant A. Block
Exploring The Role Of A Mushy, Crustal Compliant Region In Volcano Deformation, Grant A. Block
Physics & Astronomy ETDs
Volcanoes are both creative and destructive forces that have shaped and continue to shape our world from early geologic time to the present day. Continued study of volcanic processes not only better prepares us for monitoring volcanic hazards but also allows us to better understand processes fundamental to Earth as we know it, such as the generation of the atmosphere and accretion of the continents. This dissertation focuses on an integral part of volcanic processes: the trans-crustal magmatic transport system. Specifically, we investigate regions of these transport systems where magma pools in melt-rich lenses within broader regions of low melt-fraction, …
Narrowband Searches For Continuous Gravitational Waves From Known Pulsars In The First Two Parts Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Miriam Ramos Arevalo, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang
Narrowband Searches For Continuous Gravitational Waves From Known Pulsars In The First Two Parts Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Miriam Ramos Arevalo, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang
Physics & Astronomy Faculty Publications
Rotating nonaxisymmetric neutron stars (NSs) are promising sources for continuous gravitational waves (CWs). CWs may, if detected, inform us about the internal structure and equation of state of NSs. Here, we present a narrowband search for CWs from known pulsars, for which a matched-filter search can be applied. Narrowband searches are robust to mismatches between electromagnetic (EM) and gravitational emissions, in contrast to fully targeted searches where they are assumed to be phase-locked. In this work, we search for the CW counterparts emitted by 34 pulsars using data from the first and second parts of the fourth LIGO–Virgo–KAGRA observing run. …
Gwtc-4.0: Population Properties Of Merging Compact Binaries, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang
Gwtc-4.0: Population Properties Of Merging Compact Binaries, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang
Physics & Astronomy Faculty Publications
We detail the population properties of binary neutron star, neutron star–black hole binary, and binary black hole mergers using 158 events from the cumulative Gravitational-Wave Transient Catalog 4.0. The black hole primary mass distribution consists of a power-law-like continuum that steepens above 35 M⊙ with overdensities at 10 M⊙ and 35 M⊙. Binary black holes with primary masses near 10 M⊙ are more likely to have less massive secondaries, with a mass ratio distribution peaking at q=0.74+0.13−0.13, potentially a signature of stable mass transfer during binary evolution. Black hole spins are inferred to be nonextremal, with …
Constraints On Gravitational Waves From The 2024 Vela Pulsar Glitch, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Constraints On Gravitational Waves From The 2024 Vela Pulsar Glitch, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Physics & Astronomy Faculty Publications
Among known neutron stars, the Vela pulsar is one of the best targets for gravitational-wave searches. It is also one of the most prolific in terms of glitches, which are sudden frequency changes in a pulsar’s rotation. Such glitches could cause a variety of transient gravitational-wave signals. Here, we search for signals associated with a Vela glitch on 2024 April 29 in data of the two LIGO detectors from the fourth LIGO–Virgo–KAGRA observing run. We search both for seconds-scale burst-like emission, primarily from fundamental (f-)mode oscillations, and for longer quasi-monochromatic transients up to 4 months in duration, primarily …
Interfacial Redox Mediation By Amine/Alkyne-Functionalized Silicon Nanoparticles: Surfactant-Free Gold Nanoparticle Synthesis, Amber L. Garcia, Brittany Griggs, Brian S. Mitchell, Mark J. Fink, Julie P. Vanegas
Interfacial Redox Mediation By Amine/Alkyne-Functionalized Silicon Nanoparticles: Surfactant-Free Gold Nanoparticle Synthesis, Amber L. Garcia, Brittany Griggs, Brian S. Mitchell, Mark J. Fink, Julie P. Vanegas
Physics & Astronomy Faculty Publications
We develop a surfactant-free synthesis method for gold nanoparticles (AuNPs) using 2-propynylamine-functionalized silicon nanoparticles as integrated redox-active supports. Surface-anchored amine groups act as built-in reducing sites for Au3+ precursors at the hexane–water interface under ambient conditions, enabling in situ AuNP nucleation and growth. Time-resolved UV-vis spectroscopy and dynamic light scattering track the emergence of plasmonic AuNPs, while quantitative morphology analysis reveals a final population dominated by spherical and near-spherical nanoparticles (∼74%), with faceted polyhedral structures (∼4%) and dendritic, hollow, irregular, and rod-like morphologies (∼22%) as minority species. The temporal evolution proceeds from early dendritic and irregular aggregates to a …
On The True Interstellar Anisotropy Of Tev Cosmic Rays And Its Implications For The Local Interstellar Medium, Noufel D. Maalal
On The True Interstellar Anisotropy Of Tev Cosmic Rays And Its Implications For The Local Interstellar Medium, Noufel D. Maalal
Theses and Dissertations
Several ground-based cosmic ray (CR) air shower experiments have produced sky maps of intensity anisotropy in the energy range from 1 TeV to a few hundred TeVs with very high statistics and angular resolution. These measurements provide opportunities to study CR sources and propagation in the interstellar medium (ISM). Such studies present two major difficulties. Firstly, CRs are deflected by the heliospheric magnetic field on the last stretch of their journey to Earth. Secondly, measurements at different latitudes are difficult to compare, leading to uncertainties in latitudinal variations on the order of the observed anisotropy. Experiments usually assume latitudinal variations …
Frequency And Radiative Analysis Of Random Yagi-Uhf/Vhf Phased Array, Luis M. Bres, Luis A. Hernandez, Teviet Creighton
Frequency And Radiative Analysis Of Random Yagi-Uhf/Vhf Phased Array, Luis M. Bres, Luis A. Hernandez, Teviet Creighton
Physics & Astronomy Faculty Publications
This study investigates a phased array ground station capable of tracking multiple sources, multi-beamforming, electronic steering, easy scaling, and low cost. The project will develop a 20-pair dual-polarized Yagi-UHF/VHF phased array, comparing the parameters of random and uniform layouts. This study will be divided into two domains: frequency, and radiative domain. The frequency domain will explore the reception and transmission spectra analysis under several scenarios for our antennas. The radiative domain will explore the following: general side lobe analysis across both elevation and azimuth, antenna element sweep analysis, electronic beam steering analysis, electro-mechanical beam steering analysis, array density analysis, and …
Potential For Lunar Interior Science By The Gravitational-Wave Detector Lila, Mark P. Panning, Philippe Lognonné, Teviet Creighton, James Trippe, Volker Quetschke, Josipa Majstorović, Karan Jani
Potential For Lunar Interior Science By The Gravitational-Wave Detector Lila, Mark P. Panning, Philippe Lognonné, Teviet Creighton, James Trippe, Volker Quetschke, Josipa Majstorović, Karan Jani
Physics & Astronomy Faculty Publications
The laser interferometer lunar antenna (LILA), a concept for measuring sub-Hz gravitational waves on the Moon, would use laser strainmeters to obtain extremely sensitive strain measurements from 1 mHz to 1 Hz. With proposed strain sensitivities, LILA would also be able to measure the normal modes of the Moon from 1–10 mHz at high signal-to-noise ratio. Such measurements would enable significant advances in our understanding of both the spherically symmetric and even 3D deep internal structure of the Moon. Strainmeter measurements may even be able to detect the translational mode of the solid inner core of the Moon at frequencies …
Open Data From Ligo, Virgo, And Kagra Through The First Part Of The Fourth Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Open Data From Ligo, Virgo, And Kagra Through The First Part Of The Fourth Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Physics & Astronomy Faculty Publications
LIGO, Virgo, and KAGRA form a network of gravitational-wave observatories. Data and analysis results from this network are made publicly available through the Gravitational Wave Open Science Center. This paper describes open data from this network, including the addition of data from the first part of the fourth observing run and selected periods from the preceding engineering run, collected from 2023 May to 2024 January. The public dataset includes calibrated strain time series for each instrument, data from additional channels used for noise subtraction and detector characterization, and analysis data products from version 4.0 of the Gravitational-Wave Transient Catalog.
Searches For Continuous Gravitational Waves From Supernova Remnants In The First Part Of The Ligo-Virgo-Kagra Fourth Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Searches For Continuous Gravitational Waves From Supernova Remnants In The First Part Of The Ligo-Virgo-Kagra Fourth Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Physics & Astronomy Faculty Publications
We present results from directed searches for continuous gravitational waves from a sample of 15 nearby supernova remnants, likely hosting young neutron star candidates, using data from the first eight months of the fourth observing run (O4) of the LIGO–Virgo–KAGRA Collaboration. The analysis employs five pipelines: four semicoherent methods—the Band-Sampled-Data directed pipeline, Weave, and two Viterbi pipelines (single- and dual-harmonic)—and PyStoch, a cross-correlation-based pipeline. These searches cover wide frequency bands and do not assume prior knowledge of the targets’ ephemerides. No evidence of a signal is found from any of the 15 sources. We set 95% confidence-level upper limits on …
Gw230814: Investigation Of A Loud Gravitational-Wave Signal Observed With A Single Detector, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Gw230814: Investigation Of A Loud Gravitational-Wave Signal Observed With A Single Detector, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Physics & Astronomy Faculty Publications
GW230814, detected by the LIGO Livingston observatory with a signal-to-noise ratio of 42.4, represents the loudest gravitational-wave signal in the GWTC-4.0 catalog. Its source is consistent with a binary black hole coalescence with component masses m1=33.7+2.9−2.2M⊙, m2=29.9+2.1−2.8M⊙, and a small effective inspiral spin χeff=−0.01+0.06−0.07. The high signal-to-noise ratio enabled us to detect an ℓ = ∣m∣ = 4 mode in the inspiral–merger–ringdown signal for the first time (with Bayes factor ≈10), as well as enabling a range of tests of consistency between theoretical predictions and the observed waveform. While most of these tests show agreement with theoretical predictions, there are …
Gwtc-4.0: Updating The Gravitational-Wave Transient Catalog With Observations From The First Part Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Gwtc-4.0: Updating The Gravitational-Wave Transient Catalog With Observations From The First Part Of The Fourth Ligo–Virgo–Kagra Observing Run, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Miriam Ramos Arevalo, Wenhui Wang
Physics & Astronomy Faculty Publications
Version 4.0 of the Gravitational-Wave Transient Catalog (GWTC-4.0) adds new candidates detected by the LIGO, Virgo, and KAGRA observatories through the first part of the fourth observing run (O4a: 2023 May 24 15:00:00 to 2024 January 16 16:00:00 UTC) and a preceding engineering run. In these new data, we find 128 compact binary coalescence candidates that are identified by at least one of our search algorithms with a probability of astrophysical origin pastro ≥ 0.5 and that are not vetoed during event validation. We also provide detailed source property measurements for 86 of these that have a false-alarm rate …
Gwtc-4.0: Methods For Identifying And Characterizing Gravitational-Wave Transients, A. G. Abac, I. Abouelfettouh, Teviet Creighton, Mario C. Diaz, Raul Alberto Espinosa Perez, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, Wenhui Wang
Gwtc-4.0: Methods For Identifying And Characterizing Gravitational-Wave Transients, A. G. Abac, I. Abouelfettouh, 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 candidate gravitational-wave transient signals identified and characterized by the LIGO–Virgo–KAGRA Collaboration. Producing the contents of the GWTC from detector data requires complex analysis methods. These comprise techniques to model the signal; identify the transients in the data; evaluate the quality of the data and mitigate possible instrumental issues; infer the parameters of each transient; compare the data with the waveform models for compact binary coalescences; and handle the large amount of results associated with all of these different analyses. In this paper, we describe the methods employed to produce the catalog’s …
Phase-Resolved Measurement And Arbitrary Mode Conversion Of Structured Light, Somayeh Ghazanfarpour
Phase-Resolved Measurement And Arbitrary Mode Conversion Of Structured Light, Somayeh Ghazanfarpour
Electronic Theses and Dissertations
This dissertation presents a single-shot phase and amplitude retrieval technique based on spatial light modulator (SLM)-based digital holography. The proposed method enables accurate reconstruction of complex optical fields from a single interferogram, reducing sensitivity to environmental fluctuations and improving experimental stability compared to conventional multi-shot approaches. In addition, a programmable arbitrary mode converter is developed using SLM-based wavefront shaping. By introducing controlled astigmatism and engineering the differential Gouy phase between orthogonal components, the system enables flexible transformation between structured light modes, including Hermite–Gaussian and Laguerre–Gaussian beams. Numerical results demonstrate reliable phase recovery and efficient mode conversion, validating the performance of …
Hot Jupiter Atmospheres Through Time, Annabelle E. Niblett
Hot Jupiter Atmospheres Through Time, Annabelle E. Niblett
Physics and Astronomy Undergraduate Senior Theses
Transmission spectroscopy of hot Jupiters enables mass and atmospheric composition measurements, providing insight into population dynamics and evolution when other methods are hindered by stellar activity. To effectively plan observations and interpret transmission spectra, we must have a robust understanding of how atmospheres evolve over time. To that end, we present a suite of hot Jupiter transmission spectra models with ages ranging from 3 Myr to 11 Gyr. We incorporate the cooling and contraction of the planet, which impacts the atmospheric profile, and the evolution of the stellar UV spectrum, which moderates photodissociation and photoionization. Using PICASO, VULCAN, and FastChem …
Validation Of Electromagnetic Shower Development In A Reduced Alice Focal-E Detector Model Using Geant4, Isaac Lara Romo
Validation Of Electromagnetic Shower Development In A Reduced Alice Focal-E Detector Model Using Geant4, Isaac Lara Romo
Physics
This project focuses on the preliminary simulation of a reduced FoCal-E detector model for the ALICE experiment at CERN. Beamline tests were simulated using an electron gun at various incident energies, and the results were compared with those of the FoCal group. The longitudinal charge deposition per sensor layer was compared between the two setups to verify that the reduced model exhibited expected calorimeter behavior. Additionally, the transverse signal across the high-granularity sensor layers was examined to determine whether the reduced model reproduced the expected lateral development of electromagnetic showers. The results obtained from these measurements show that the reduced …
1d Crust-Magnetosphere Coupling Model For Magnetars, Kennedy M. Jeter
1d Crust-Magnetosphere Coupling Model For Magnetars, Kennedy M. Jeter
Dissertations, Theses, and Capstone Projects
Magnetars are the most extremely magnetized objects in the universe. Their strong magnetic fields generate high-energy magnetic flares with instantaneous luminosity that can outshine their host galaxy. Previous works have explored how Hall drift in the crust affects the dynamics of magnetic field lines in the magnetosphere. This work investigates how a change in the magnetosphere, such as a flare or an outburst, can excite Hall evolution in the crust. We investigate how the twisting and untwisting of magnetic field lines in a magnetar’s magnetosphere launches Hall waves through its crust using a one-dimensional numerical model. We use the Dedalus …