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Full-Text Articles in Physical Sciences and Mathematics

Search For Core Collapse Supernovae Signals In Ligo’S Third Observation Run Using A Network Of Gravitational Wave Detectors Integrated With A Multiclass Convolutional Neural Network, Shahrear Khan Faisal, Gaukhar Nurbek, Michael Benjamin, Bhawana Sedhai, Soma Mukherjee Sep 2024

Search For Core Collapse Supernovae Signals In Ligo’S Third Observation Run Using A Network Of Gravitational Wave Detectors Integrated With A Multiclass Convolutional Neural Network, Shahrear Khan Faisal, Gaukhar Nurbek, Michael Benjamin, Bhawana Sedhai, Soma Mukherjee

Physics and Astronomy Faculty Publications and Presentations

In the existing body of literature, numerous waveforms of core collapse supernovae (CCSN) have emerged from extensive simulations conducted in high-performance computing facilities globally. These waveforms exhibit distinct characteristics related to their explosion mechanisms, influenced by parameters such as progenitor mass, angular momentum, gravitational wave energy, peak frequency, duration, and equation of state. Core collapse supernovae stand out as highly anticipated sources in LIGO’s fourth observation (O4) run, prompting dedicated efforts to detect them. The integration of machine learning, specifically convolutional neural networks (CNN), has become a pivotal avenue for analysis. This study addresses a fundamental query: how can a …


Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The Third Observing Run Of Advanced Ligo And Advanced Virgo, Marek J. Szczepańczyk, Yanyan Zheng, Javier M. Antelis, Michael G. Benjamin, Marie-Anne Bizouard, Alejandro Casallas-Lagos, Pablo Cerda-Duran, Derek Davis, Dorota Gondek-Rosinska, Soma Mukherjee Aug 2024

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The Third Observing Run Of Advanced Ligo And Advanced Virgo, Marek J. Szczepańczyk, Yanyan Zheng, Javier M. Antelis, Michael G. Benjamin, Marie-Anne Bizouard, Alejandro Casallas-Lagos, Pablo Cerda-Duran, Derek Davis, Dorota Gondek-Rosinska, Soma Mukherjee

Physics and Astronomy Faculty Publications and Presentations

We present the results from a search for gravitational-wave transients associated with core-collapse supernovae observed optically within 30 Mpc during the third observing run of Advanced LIGO and Advanced Virgo. No gravitational wave associated with a core-collapse supernova has been identified. We then report the detection efficiency for a variety of possible gravitational-wave emissions. For neutrino-driven explosions, the distance at which we reach 50% detection efficiency is up to 8.9 kpc, while more energetic magnetorotationally driven explosions are detectable at larger distances. The distance reaches for selected models of the black hole formation, and quantum chromodynamics phase transition are also …


Answers To Frequently Asked Questions About The Pulsar Timing Array Hellings And Downs Curve, Joseph D. Romano, Bruce Allen Jul 2024

Answers To Frequently Asked Questions About The Pulsar Timing Array Hellings And Downs Curve, Joseph D. Romano, Bruce Allen

Physics and Astronomy Faculty Publications and Presentations

We answer frequently asked questions (FAQs) about the Hellings and Downs correlation curve—the ‘smoking-gun’ signature that pulsar timing arrays (PTAs) have detected gravitational waves (GWs). Many of these questions arise from inadvertently applying intuition about the effects of GWs on LIGO-like detectors to the case of pulsar timing, where not all of it applies. This is because Earth-based detectors, like LIGO and Virgo, have arms that are short (km scale) compared to the wavelengths of the GWs that they detect (≈102–104 km). In contrast, PTAs respond to GWs whose wavelengths (tens of light-years) are much shorter than their arms (a …


Variable Radio Emission Of Neutron Star X-Ray Binary Ser X–1 During Its Persistent Soft State, E. C. Pattie, Thomas J. Maccarone, Alexandra J. Tetarenko, James C. A. Miller-Jones, Manuel Pichardo Marcano, Liliana E. Rivera Sandoval Jul 2024

Variable Radio Emission Of Neutron Star X-Ray Binary Ser X–1 During Its Persistent Soft State, E. C. Pattie, Thomas J. Maccarone, Alexandra J. Tetarenko, James C. A. Miller-Jones, Manuel Pichardo Marcano, Liliana E. Rivera Sandoval

Physics and Astronomy Faculty Publications and Presentations

Ser X–1 is a low-mass neutron star X-ray binary and has been persistently accreting since its discovery in the 1960s. It has always been observed to be in a soft spectral state and has never showed substantial long-term X-ray variability. Ser X–1 has one previous radio observation in the literature in which radio emission was detected during this soft state, which is contrary to the behavior of black hole X-ray binaries. We have recently obtained 10 randomly sampled radio epochs of Ser X–1 in order to further investigate its anomalous soft-state radio emission. Out of 10 epochs, we find 8 …


Hierarchical Search Method For Gravitational Waves From Stellar-Mass Binary Black Holes In Noisy Space-Based Detector Data, Yao Fu, Yan Wang, Soumya D. Mohanty Jul 2024

Hierarchical Search Method For Gravitational Waves From Stellar-Mass Binary Black Holes In Noisy Space-Based Detector Data, Yao Fu, Yan Wang, Soumya D. Mohanty

Physics and Astronomy Faculty Publications and Presentations

Future space-based laser interferometric detectors, such as LISA, will be able to detect gravitational waves (GWs) generated during the inspiral phase of stellar-mass binary black holes (SmBBHs). These detections contain a wealth of important information concerning astrophysical formation channels and fundamental physics constraints. However, the detection and characterization of GWs from SmBBHs poses a formidable data analysis challenge, arising from the large number of wave cycles that make the search extremely sensitive to mismatches in signal and template parameters in a likelihood-based approach. This makes the search for the maximum of the likelihood function over the signal parameter space an …


A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh Jul 2024

A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh

Physics and Astronomy Faculty Publications and Presentations

The non-Hermitian skin effect (NHSE) is a well-known phenomenon in open topological systems that causes a large number of eigenstates to become localized at the boundary. Although many aspects of its theory have been investigated in linear systems, this phenomenon remains novel in nonlinear models. In the first step of this paper, we look at the conditions for the presence of quasi-skin modes in a semi-infinite, one-dimensional, nonlinear, nonreciprocal lattice. In the following phase, we explore the survival time of the quasi-skin mode in a finite nonlinear lattice with open edges. We study the dependency of the survival time on …


Optimal Reconstruction Of The Hellings And Downs Correlation, Bruce Allen, Joseph D. Romano Jul 2024

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

Physics and Astronomy Faculty Publications and Presentations

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 the ``smoking gun'' 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 …


Strong Edge Burst With Bipolar Non-Hermitian Skin Effect, Cem Yuce, Hamidreza Ramezani Jun 2024

Strong Edge Burst With Bipolar Non-Hermitian Skin Effect, Cem Yuce, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

We consider a system exhibiting the bipolar non-Hermitian skin effect (NHSE), where bipolar skin states are localized at both edges, and discuss how the topological funneling effect can occur with a single focal point in this system. We explore a topological phase transition from bipolar NHSE to NHSE, which alters the localization characteristics of the eigenstates. After the transition, both the delocalized and bipolar skin states transform into skin states. The non-Hermitian edge burst is a novel and unexpected feature of non-Hermitian quantum dynamics, characterized by substantial particle loss at the boundary of a system. Using the model displaying bipolar …


Simultaneous Chandra And Hst Observations Of The Quiescent Neutron Star Low-Mass X-Ray Binaries In 47 Tucanae, M. Van Den Berg, Liliana E. Rivera Sandoval, C O. Heinke, H. N. Cohn, P. M. Lugger, J. E. Grindlay, P. D. Edmonds, J. Anderson, A. Catuneanu Jun 2024

Simultaneous Chandra And Hst Observations Of The Quiescent Neutron Star Low-Mass X-Ray Binaries In 47 Tucanae, M. Van Den Berg, Liliana E. Rivera Sandoval, C O. Heinke, H. N. Cohn, P. M. Lugger, J. E. Grindlay, P. D. Edmonds, J. Anderson, A. Catuneanu

Physics and Astronomy Faculty Publications and Presentations

We present simultaneous Chandra X-ray Observatory and Hubble Space Telescope observations of three certain (X5, X7, W37) and two likely (X4, W17) quiescent neutron star low-mass X-ray binaries (qLMXBs) in the globular cluster 47 Tuc. We study these systems in the X-ray, optical, and near-ultraviolet (NUV) using the simultaneous data and additional non-contemporaneous HST data. We have discovered a blue and variable NUV counterpart to W17. We have not securely identified the eclipsing qLMXB W37 in the optical or NUV. Deeper high-resolution imaging is needed to further investigate the faint NUV excess near the centre of the W37 error circle. …


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 Jun 2024

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 and Astronomy Faculty Publications and Presentations

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 …


Unbiased Estimation Of Gravitational-Wave Anisotropies From Noisy Data, Nikolaos Kouvatsos, Alexander C. Jenkins, Arianna I. Renzini, Joseph D. Romano, Mairi Sakellariadou May 2024

Unbiased Estimation Of Gravitational-Wave Anisotropies From Noisy Data, Nikolaos Kouvatsos, Alexander C. Jenkins, Arianna I. Renzini, Joseph D. Romano, Mairi Sakellariadou

Physics and Astronomy Faculty Publications and Presentations

One of the most exciting targets of current and future gravitational-wave observations is the angular power spectrum of the astrophysical GW background. This cumulative signal encodes information about the large-scale structure of the Universe, as well as the formation and evolution of compact binaries throughout cosmic time. However, the finite rate of compact binary mergers gives rise to temporal shot noise, which introduces a significant bias in measurements of the angular power spectrum if not explicitly accounted for. Previous work showed that this bias can be removed by cross-correlating GW sky maps constructed from different observing times. However, this …


A Novel Positive-Contrast Magnetic Resonance Imaging Line Marker For High-Dose-Rate (Hdr) Mri-Assisted Radiosurgery (Mars), Li Wang, Yao Ding, Teresa L. Bruno, R Jason. Stafford, Eric Lin, Tharakeswara K. Bathala, Jeremiah W. Sanders, Matthew S. Ning, Jingfei Ma, Karen S. Martirosyan May 2024

A Novel Positive-Contrast Magnetic Resonance Imaging Line Marker For High-Dose-Rate (Hdr) Mri-Assisted Radiosurgery (Mars), Li Wang, Yao Ding, Teresa L. Bruno, R Jason. Stafford, Eric Lin, Tharakeswara K. Bathala, Jeremiah W. Sanders, Matthew S. Ning, Jingfei Ma, Karen S. Martirosyan

Physics and Astronomy Faculty Publications and Presentations

Magnetic resonance imaging (MRI) can facilitate accurate organ delineation and optimal dose distributions in high-dose-rate (HDR) MRI-Assisted Radiosurgery (MARS). Its use for this purpose has been limited by the lack of positive-contrast MRI markers that can clearly delineate the lumen of the HDR applicator and precisely show the path of the HDR source on T1- and T2-weighted MRI sequences. We investigated a novel MRI positive-contrast HDR brachytherapy or interventional radiotherapy line marker, C4:S, consisting of C4 (visible on T1-weighted images) complexed with saline. Longitudinal relaxation time (T1) and transverse relaxation time (T2) for C4:S were measured on a 1.5 T …


Remnant Polarization And Structural Arrangement In P(Vdf-Trfe) Electrospun Fiber Meshes Affect Osteogenic Differentiation Of Human Mesenchymal Stromal Cells, Bahareh Azimi, Massimiliano Labardi, Mohammad Sajad Sorayani Bafqi, Teresa Macchi, Claudio Ricci, Veronica Carnicelli, Lorenzo Scarpelli, Istiak Hussain, Francesca Matino, Mohammed Uddin May 2024

Remnant Polarization And Structural Arrangement In P(Vdf-Trfe) Electrospun Fiber Meshes Affect Osteogenic Differentiation Of Human Mesenchymal Stromal Cells, Bahareh Azimi, Massimiliano Labardi, Mohammad Sajad Sorayani Bafqi, Teresa Macchi, Claudio Ricci, Veronica Carnicelli, Lorenzo Scarpelli, Istiak Hussain, Francesca Matino, Mohammed Uddin

Physics and Astronomy Faculty Publications and Presentations

Highlights

  • The type of solvent had noticeable effects on morphology and piezoelectric properties of P(VDF-TrFE) electrospun fibers.

  • Using MEK as a solvent and specific environmental conditions led to the obtainment of surface nanopores.

  • Uniaxially aligned fibers exhibited higher β phase and mechanical properties than random ones.

  • Randomly oriented fibers had higher remnant piezoelectric properties (Vout, d31 piezoelectric coefficient) than aligned ones.

  • Human mesenchymal stem cells cultured on randomly oriented fibers showed an accelerated osteogenic differentiation.

Abstract

Many tissues and cells are influenced by mechano-electric stimulation, thus the application of piezoelectric materials has recently received considerable attention in tissue engineering. …


A Search For Intermediate-Mass Black Holes In Compact Stellar Systems Through Optical Emissions From Tidal Disruption Events, Richard T. Pomeroy, Mark A. Norris Apr 2024

A Search For Intermediate-Mass Black Holes In Compact Stellar Systems Through Optical Emissions From Tidal Disruption Events, Richard T. Pomeroy, Mark A. Norris

Physics and Astronomy Faculty Publications and Presentations

Intermediate-mass black holes (IMBH) are expected to exist in globular clusters (GCs) and compact stellar systems (CSS) in general, but none have been conclusively detected. Tidal disruption events (TDEs), where a star is tidally disrupted by the gravitational field of a black hole, have been observed to occur around the supermassive black holes (SMBH) found at the centres of galaxies, and should also arise around IMBHs, especially in the dense stellar cores of CSS's. However, to date none have been observed in such environments. Using data from the Zwicky Transient Facility (ZTF) we search for TDEs associated with CSS, but …


Search For Extreme Mass Ratio Inspirals Using Particle Swarm Optimization And Reduced Dimensionality Likelihoods, Xiao-Bo Zou, Soumya Mohanty, Hong-Gang Luo, Yu-Xiao Liu Apr 2024

Search For Extreme Mass Ratio Inspirals Using Particle Swarm Optimization And Reduced Dimensionality Likelihoods, Xiao-Bo Zou, Soumya Mohanty, Hong-Gang Luo, Yu-Xiao Liu

Physics and Astronomy Faculty Publications and Presentations

Extreme-mass-ratio inspirals (EMRIs) are significant observational targets for spaceborne gravitational wave detectors, namely, LISA, Taiji, and Tianqin, which involve the inspiral of stellar-mass compact objects into massive black holes (MBHs) with a mass range of approximately 104 ∼107𝑀⊙ . EMRIs are estimated to produce long-lived gravitational wave signals with more than 105 cycles before plunge, making them an ideal laboratory for exploring the strong-gravity properties of the spacetimes around the MBHs, stellar dynamics in galactic nuclei, and properties of the MBHs itself. However, the complexity of the waveform model, which involves the superposition of multiple harmonics, as well as the …


Reevaluating The Origin Of Detectable Cataclysmic Variables In Globular Clusters: Testing The Importance Of Dynamics, Liliana Rivera Sandoval, Diogo Belloni, Miriam Ramos Arevalo Apr 2024

Reevaluating The Origin Of Detectable Cataclysmic Variables In Globular Clusters: Testing The Importance Of Dynamics, Liliana Rivera Sandoval, Diogo Belloni, Miriam Ramos Arevalo

Physics and Astronomy Faculty Publications and Presentations

Based on the current detectable cataclysmic variable (CV) population in Galactic globular clusters (GCs), we show that there is not a clear relation between the number of sources per unit of mass and the stellar encounter rate, the cluster mass, or the cluster central density. If any, only in the case of core-collapsed GCs could there be an anticorrelation with the stellar encounter rate. Our findings contrast with previous studies where clear positive correlations were identified. Our results suggest that correlations between faint X-ray sources, from which often conclusions for the CV population are drawn, and the GC parameters considered …


A Joint Fermi-Gbm And Swift-Bat Analysis Of Gravitational-Wave Candidates From The Third Gravitational-Wave Observing Run, C. Fletcher, J. Wood, R. Hamburg, Michael G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Mar 2024

A Joint Fermi-Gbm And Swift-Bat Analysis Of Gravitational-Wave Candidates From The Third Gravitational-Wave Observing Run, C. Fletcher, J. Wood, R. Hamburg, Michael G. Benjamin, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics and Astronomy Faculty Publications and Presentations

We present Fermi Gamma-ray Burst Monitor (Fermi-GBM) and Swift Burst Alert Telescope (Swift-BAT) searches for gamma-ray/X-ray counterparts to gravitational-wave (GW) candidate events identified during the third observing run of the Advanced LIGO and Advanced Virgo detectors. Using Fermi-GBM onboard triggers and subthreshold gamma-ray burst (GRB) candidates found in the Fermi-GBM ground analyses, the Targeted Search and the Untargeted Search, we investigate whether there are any coincident GRBs associated with the GWs. We also search the Swift-BAT rate data around the GW times to determine whether a GRB counterpart is present. No counterparts are found. Using both the Fermi-GBM Targeted Search …


Adsorption Of Crystal Violet Dye From Synthetic Wastewater By Ball-Milled Royal Palm Leaf Sheath, Neloy Sen, Nawrin Rahman Shefa, Kismot Reza, Sk Md Ali Zaker Shawon, Md. Wasikur Rahman Mar 2024

Adsorption Of Crystal Violet Dye From Synthetic Wastewater By Ball-Milled Royal Palm Leaf Sheath, Neloy Sen, Nawrin Rahman Shefa, Kismot Reza, Sk Md Ali Zaker Shawon, Md. Wasikur Rahman

Physics and Astronomy Faculty Publications and Presentations

The current study shows that using a batch approach to remove crystal violet dye from synthetic wastewater is feasible when using royal palm leaf sheath powder as an adsorbent. In order to investigate the effects of many parameters, including starting concentration, pH effect, dye concentration, adsorbent dose, contact time, and temperature, experiments were carried out under various operating conditions. Maximum removal was obtained at pH 6 and at a concentration of 100 ppm, which are considered as ideal values. The influence of pH and dye concentration was shown to be substantial. Langmuir, Freundlich, and Temkin isotherm models were fitted to …


Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan Van Roestel, David R. Zurek Mar 2024

Strongly Magnetized Accretion In Two Ultracompact Binary Systems, Thomas J. Maccarone, Thomas Kupfer, Edgar Najera Casarrubias, Liliana E. Rivera Sandoval, Aarran W. Shaw, Christoper T. Britt, Jan Van Roestel, David R. Zurek

Physics and Astronomy Faculty Publications and Presentations

We present the discoveries of two of AM CVn systems, Gaia14aae and SDSS J080449.49+161624.8, which show X-ray pulsations at their orbital periods, indicative of magnetically collimated accretion. Both also show indications of higher rates of mass transfer relative to the expectations from binary evolution driven purely by gravitational radiation, based on existing optical data for Gaia14aae, which show a hotter white dwarf temperature than expected from standard evolutionary models, and X-ray data for SDSS J080449.49+161624.8 which show a luminosity 10−100 times higher than those for other AM CVn at similar orbital periods. The higher mass transfer rates could be driven …


Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid Mar 2024

Powerful Radio Sources In The Southern Sky. Iii. First Results Of The Optical Spectroscopic Campaign, A. García-Pérez, H. A. Peña-Herazo, A. Jimenez-Gallardo, V. Chavushyan, F. Massaro, S. V. White, A. Capetti, B. Balmaverde, W. R. Forman, Juan P. Madrid

Physics and Astronomy Faculty Publications and Presentations

We recently built the G4Jy-3CRE catalog of extragalactic radio sources. This catalog lists 264 powerful radio sources selected with similar criteria to those of the revised Third Cambridge Catalog, but visible from the Southern Hemisphere. A literature search revealed that 119 sources in the G4Jy-3CRE catalog (i.e., 45%) lack a firm spectroscopic redshift measurement. Here, we present a campaign aimed at acquiring optical spectra of G4Jy-3CRE sources and measuring their redshifts. We used single-slit observations obtained with the Víctor Blanco Telescope, the New Technology Telescope, the Southern Astrophysical Research Telescope, and the 2.1 m telescope of the Observatorio Astronómico Nacional …


Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton Mar 2024

Comment On “Spectral Shifts In General Relativity,” [Am. J. Phys. 62(10), 903–907 (1994)], Joseph D. Romano, Teviet Creighton

Physics and Astronomy Faculty Publications and Presentations

No abstract provided.


Roaring To Softly Whispering: X-Ray Emission After ∼3.7 Yr At The Location Of The Transient At2018cow And Implications For Accretion-Powered Scenarios, Giulia Migliori, R. Margutti, B. D. Metzger, R. Chornock, C. Vignali, D. Brethauer, Liliana E. Rivera Sandoval, J. S. Bright, T. Laskar, D. Milisavljevic Feb 2024

Roaring To Softly Whispering: X-Ray Emission After ∼3.7 Yr At The Location Of The Transient At2018cow And Implications For Accretion-Powered Scenarios, Giulia Migliori, R. Margutti, B. D. Metzger, R. Chornock, C. Vignali, D. Brethauer, Liliana E. Rivera Sandoval, J. S. Bright, T. Laskar, D. Milisavljevic

Physics and Astronomy Faculty Publications and Presentations

We present the first deep X-ray observations of luminous fast blue optical transient (LFBOT) AT 2018cow at ∼3.7 yr since discovery, together with the reanalysis of the observation at δt ∼ 220 days. X-ray emission is significantly detected at a location consistent with AT 2018cow. The very soft X-ray spectrum and sustained luminosity are distinct from the spectral and temporal behavior of the LFBOT in the first ∼100 days and would possibly signal the emergence of a new emission component, although a robust association with AT 2018cow can only be claimed at δt ∼ 220 days, while at …


Thermal Phonon Fluctuations And Stability Of The Magnetic Dual Chiral Density Wave Phase In Dense Qcd, Efrain J. Ferrer, William Gyory, Vivian De La Incera Feb 2024

Thermal Phonon Fluctuations And Stability Of The Magnetic Dual Chiral Density Wave Phase In Dense Qcd, Efrain J. Ferrer, William Gyory, Vivian De La Incera

Physics and Astronomy Faculty Publications and Presentations

We study the stability against thermal phonon fluctuations of the magnetic dual chiral density wave (MDCDW) phase, an inhomogeneous phase arising in cold, dense QCD in a magnetic field. Following a recent study that demonstrated the absence of the Landau-Peierls (LP) instability from this phase, we calculate the (threshold) temperature at which the phonon fluctuations wash out the long-range order over a range of magnetic fields and densities relevant to astrophysical applications. Using a high-order Ginzburg-Landau expansion, we find that the threshold temperature is very near the critical temperature for fields of order 10 18     G and still a sizable …


Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang Feb 2024

Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang

Physics and Astronomy Faculty Publications and Presentations

Undergraduate research experiences are an instrumental component of student development, increasing conceptual understanding, promoting inquiry-based learning, and guiding potential career aspirations. Moving one step further, as research continues to become more interdisciplinary, there exists potential to accelerate student growth by granting additional perspectives through collaborative research. This study demonstrates the utilization of a model collaborative research project, specifically investigating the development of sorbent technologies for efficient CO2 capture, which is an important research area for improving environmental sustainability. A model CO2 sorbent system of heteroatom-doped porous carbon is utilized to enable students to gain knowledge of adsorption processes, through combined …


Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang Feb 2024

Research Experiences Via Integrating Simulations And Experiments (Revise): A Model Collaborative Research Project For Undergraduate Students In Co2 Sorbent Design, Anthony Griffin, Neziah Smith, Mark Robertson, Bianca Nunez, Jacob Mccraw, Haoyuan Chen, Zhe Qiang

Physics and Astronomy Faculty Publications and Presentations

Undergraduate research experiences are an instrumental component of student development, increasing conceptual understanding, promoting inquiry-based learning, and guiding potential career aspirations. Moving one step further, as research continues to become more interdisciplinary, there exists potential to accelerate student growth by granting additional perspectives through collaborative research. This study demonstrates the utilization of a model collaborative research project, specifically investigating the development of sorbent technologies for efficient CO2 capture, which is an important research area for improving environmental sustainability. A model CO2 sorbent system of heteroatom-doped porous carbon is utilized to enable students to gain knowledge of adsorption processes, through combined …


Inferring Binary Parameters With Dual-Line Gravitational Wave Detection From Tight Inspiraling Double Neutron Stars, Wen-Fan Feng, Jie-Wen Chen, Tan Liu, Yan Wang, Soumya D. Mohanty Feb 2024

Inferring Binary Parameters With Dual-Line Gravitational Wave Detection From Tight Inspiraling Double Neutron Stars, Wen-Fan Feng, Jie-Wen Chen, Tan Liu, Yan Wang, Soumya D. Mohanty

Physics and Astronomy Faculty Publications and Presentations

Neutron star (NS) binaries can be potentially intriguing gravitational wave sources, with both high- and low-frequency radiation from the possibly aspherical individual stars and the binary orbit, respectively. The successful detection of such a dual-line source could provide fresh insights into binary geometry and NS physics. In the absence of electromagnetic observations, we develop a strategy for inferring the spin-orbit misalignment angle using the tight dual-line double NS system under the spin-orbit coupling. Based on the four-year joint detection of a typical dual-line system with the Laser Interferometer Space Antenna and Cosmic Explorer, we find that the misalignment angle and …


Swarm Intelligence Methods For Extreme Mass Ratio Inspiral Search: First Application Of Particle Swarm Optimization, Xiao-Bo Zou, Soumya D. Mohanty, Hong-Gang Luo, Yu-Xiao Liu Feb 2024

Swarm Intelligence Methods For Extreme Mass Ratio Inspiral Search: First Application Of Particle Swarm Optimization, Xiao-Bo Zou, Soumya D. Mohanty, Hong-Gang Luo, Yu-Xiao Liu

Physics and Astronomy Faculty Publications and Presentations

Swarm intelligence (SI) methods are nature-inspired metaheuristics for global optimization that exploit a coordinated stochastic search strategy by a group of agents. Particle swarm optimization (PSO) is an established SI method that has been applied successfully to the optimization of rugged high-dimensional likelihood functions, a problem that represents the main bottleneck across a variety of gravitational wave (GW) data analysis challenges. We present results from the first application of PSO to one of the most difficult of these challenges, namely the search for the Extreme Mass Ratio Inspiral (EMRI) in data from future spaceborne GW detectors such as LISA, Taiji, …


Axion-Polaritons In Quark Stars: A Possible Solution To The Missing Pulsar Problem, Efrain J. Ferrer, Vivian De La Incera Feb 2024

Axion-Polaritons In Quark Stars: A Possible Solution To The Missing Pulsar Problem, Efrain J. Ferrer, Vivian De La Incera

Physics and Astronomy Faculty Publications and Presentations

This paper proposes an alternative mechanism to solve the so-called missing pulsar problem, a standing paradox between the theoretical expectations about the number of pulsars that should exist in the galaxy center of the Milky Way and their absence in the observations. The mechanism is based on the transformation of incident γ rays into hybridized modes, known as axion-polaritons, which can exist inside highly magnetized quark stars with a quark matter phase known as the magnetic dual chiral density wave phase. This phase, which is favored over several other dense matter phases candidates at densities a few times nuclear saturation …


Low Complexity Radio Frequency Interference Mitigation For Radio Astronomy Using Large Antenna Array, Zaid Bin Tariq, Teviet Creighton, Louis Percy Dartez, Naofal Al-Dhahir, Murat Torlak Jan 2024

Low Complexity Radio Frequency Interference Mitigation For Radio Astronomy Using Large Antenna Array, Zaid Bin Tariq, Teviet Creighton, Louis Percy Dartez, Naofal Al-Dhahir, Murat Torlak

Physics and Astronomy Faculty Publications and Presentations

With the ongoing growth in radio communications, there is an increased contamination of radio astronomical source data, which hinders the study of celestial radio sources. In many cases, fast mitigation of strong radio frequency interference (RFI) is valuable for studying short lived radio transients so that the astronomers can perform detailed observations of celestial radio sources. The standard method to manually excise contaminated blocks in time and frequency makes the removed data useless for radio astronomy analyses. This motivates the need for better radio frequency interference (RFI) mitigation techniques for array of size M antennas. Although many solutions for mitigating …


Advancements In Glitch Subtraction Systems For Enhancing Gravitational Wave Data Analysis: A Brief Review, Mohammad Abu Thaher Chowdhury Jan 2024

Advancements In Glitch Subtraction Systems For Enhancing Gravitational Wave Data Analysis: A Brief Review, Mohammad Abu Thaher Chowdhury

Physics and Astronomy Faculty Publications and Presentations

Glitches are transitory noise artifacts that degrade the detection sensitivity and accuracy of interferometric observatories such as LIGO and Virgo in gravitational wave astronomy. Reliable glitch subtraction techniques are essential for separating genuine gravitational wave signals from background noise and improving the accuracy of astrophysical investigations. This review study summarizes the main glitch subtraction methods used in the industry. We talk about the efficacy of classic time-domain techniques in real-time applications, like matched filtering and regression methods. The robustness of frequency-domain approaches, such as wavelet transformations and spectral analysis, in detecting and mitigating non-stationary glitches is assessed. We also investigate …