Physics Commons^™

A Transferable Force Field For Simulating Adsorption In Metal–Organic Frameworks With Open Metal Sites Based On The 12–6–4 Lennard-Jones Potential, Meng Du, Alan Rodriguez, Matthew Z. Lin, Haoyuan Chen

Physics & Astronomy Faculty Publications

Metal–organic frameworks (MOFs) that contain coordinatively unsaturated open metal sites (OMSs) provide strong host–guest interactions, making them promising sorbents for low-concentration gas adsorption applications such as direct air capture and atmospheric water harvesting. However, accurately modeling host–guest interactions involving OMSs remains challenging for classical force fields (FFs) based on the 12–6 Lennard–Jones (LJ) potential, as the polarization effect of the guest molecule induced by the positively charged OMS is not considered. Here, we introduce an FF based on the 12–6–4 LJ potential, which incorporates charge–induced dipole interactions and is parametrized against a diverse set of host–guest potential energy surfaces (PESs) …

Spectroscopic Investigations On Polyvinylidene Fluoride Nanofibers, Parinaz Amaniabdolmalaki, Jui Vitthal Kharade, Alexandro Trevino, Lydia Morales, Karen Lozano, Victoria Padilla, Karen S. Martirosyan, Horacio Vasquez, Mircea Chipara

Physics & Astronomy Faculty Publications

The production of polyvinylidene fluoride nanofibers by force-spinning from polymer solutions was confirmed by electron microscopy. The structural and phase characteristics of the resulting nanofiber mats were examined using Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode, Raman spectroscopy, and X-ray Diffraction. Results from all these techniques consistently indicated that both the powder and the mats of polyvinylidene fluoride predominantly contain the α phase, with a small admixture of the β phase. Within experimental errors, no other phases were noticed both in the powder and in the as-obtained mats. The ratios of the areas of the Raman lines at …

Gpu And Pso Accelerated Low-Latency Fully-Coherent All-Sky Search For Compact Binary Coalescences, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

The fully-coherent all-sky (FCAS) search, which combines data from a gravitational wave detector network into a single likelihood function, is the preferred method prescribed by statistical theory for Gaussian noise. However, so far, its exorbitant computational cost has blocked its use for compact binary coalescence searches. We introduce a solution combining Particle Swarm Optimization with Graphics Processing Unit (GPU) acceleration that is ≈ 50-fold faster than real-time analysis. This transforms the prospect of a low-latency FCAS search on all GW data into a practical reality for the first time. With large-scale simulations enabled by this speedup, we examine the issue …

Efficient Search For Detection Candidates Using A Peak Finder Strategy For All-Sky-All-Frequency Gravitational Wave Radiometer, Arindam Sharma, Deepali Agarwal, Sanjit Mitra

Physics & Astronomy Faculty Publications

The first all-sky-all-frequency (ASAF) radiometer search was conducted using data from the first three observing runs of the Advanced LIGO and Advanced Virgo detectors. The significance of this search lies in its fast and unmodeled approach, leveraging a cross-correlation technique to identify common signals across the detector network. As a result, this method serves as an excellent alternative to search for unknown or poorly modeled continuous wave sources and narrow band components of the gravitational wave (GW) background. For continuous wave sources whose waveform can be modeled, this method can serve as the first stage of a hierarchical scheme by …

Gauge-Invariant Gravitational Wave Polarization In Metric F(R) Gravity With Cosmological Implications, Ramesh Radhakrishnan, David Mcnutt, Delaram Mirfendereski, Alejandro Pinero, Eric Davis, William Julius, Gerald Cleaver

Physics & Astronomy Faculty Publications

We develop a fully gauge-invariant analysis of gravitational-wave polarizations in metric 𝑓⁡(𝑅) gravity with a particular focus on the modified Starobinsky model 𝑓⁡(𝑅) =𝑅 +𝛼⁢𝑅2 −2⁢Λ, whose constant-curvature solution 𝑅𝑑 =4⁢Λ provides a natural de Sitter background for both early- and late-time cosmology. Linearizing the field equations around this background, we derive the Klein–Gordon equation for the curvature perturbation 𝛿⁢𝑅 and show that the scalar propagating mode acquires a mass 𝑚2𝜓 =1/(6⁢𝛼), highlighting how the same scalar degree of freedom governs inflationary dynamics at high curvature and the propagation of gravitational waves in the current accelerating Universe. Using the scalar–vector–tensor …

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 …

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

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 …

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 …

Constraining Deviations From The Kerr Metric Via A Bumpy Parametrization And Particle Swarm Optimization In Extreme Mass-Ratio Inspirals, Xiaobo Zou, Xingyu Zhong, Wen-Biao Han, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

The measurement of deviations in the Kerr metric using gravitational-wave observations will provide a clear signal of new physics. Previous studies have developed multiple parametrizations (e.g., “bumpy” spacetime) to characterize such deviations in extreme mass-ratio inspirals (EMRIs). These approaches often rely on the Fisher information matrix (FIM) formalism to quantify the constraining power of future space-borne gravitational-wave detectors, such as LISA and Tianqin. For instance, using the analytical kludge waveform model under varying source configurations, such methods have achieved constraint sensitivity levels ranging from 10−4 to 10−2 on the dimensionless bumpy parameter 𝛿⁢˜𝑄 for LISA. In this paper, we advance …

Gw231123: A Binary Black Hole Merger With Total Mass 190–265 M⊙, 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

On 2023 November 23 the two LIGO observatories both detected GW231123, a gravitational-wave signal consistent with the merger of two black holes with masses and (90\% credible intervals), at luminosity distance 0.7-4.1 Gpc and redshift of , and a network signal-to-noise ratio of 20.7. Both black holes exhibit high spins, and respectively. A massive black hole remnant is supported by an independent ringdown analysis. Some properties of GW231123 are subject to large systematic uncertainties, as indicated by differences in inferred parameters between signal models. The primary black hole lies within or above the theorized mass gap where black holes between …

The Perfect Host: Jwst Cepheid Observations In A Background-Free Type Ia Supernova Host Confirm No Bias In Hubble-Constant Measurements, Adam G. Riess, Siyang Li, Gagandeep S. Anand, Wenlong Yuan, Louise Breuval, Stefano Casertano, Lucas M. Macri, Dan Scolnic, Yukei S. Murakami, Alexei V. Filippenko

Physics & Astronomy Faculty Publications

Cycle 1 JWST observations of Cepheids in Type Ia supernova (SN Ia) hosts resolved their red-giant-dominated near-infrared backgrounds, sharply reducing crowding and showing that photometric bias in lower-resolution Hubble Space Telescope (HST) data does not account for the Hubble tension. We present cycle 2 JWST observations of >100 Cepheids in NGC 3447, a unique system that pushes this test to the limit by transitioning from low to no background contamination. NGC 3447, an SN Ia host at D ≈ 25 Mpc, is an interacting pair comprising (i) a spiral with mixed stellar populations, typical of H0 calibrators, and (ii) a …

Tess Light Curves And Period Changes In Low-Mass Eclipsing Binary Bb Persei, Marek Wolf, Petr Zasche, Miloslav Zejda, Martin Mašek, Andrej Mudray, Hana Kučáková, Waldemar Ogłoza, Jaroslav Merc, Jan Kára, Vojtěch Dienstbier

Physics & Astronomy Faculty Publications

We present a detailed analysis of the low-mass detached eclipsing binary system BB Persei, which contains two K-type stars in a circular orbit with a short period of 0.4856 d. We used light curves from the Transiting Exoplanet Survey Satellite (Tess), which observed BB Per in five sectors, to determine its photometric properties and a precise orbital ephemeris. The solution of the Tess light curve in Phoebe results in a detached configuration, where the temperature of the primary component was fixed to T 1 = 5 300 K according to Lamost, which gives us T 2 = 5 050 ± …

Six New Doubly Eclipsing Quadruples In A 2+2 Architecture, Petr Zasche, Hana Kučáková, Jan Kára, Jaroslav Merc, Z. Henzl, Martin Mašek, L. Červinka, Vojtěch Dienstbier

Physics & Astronomy Faculty Publications

The study presents a confirmation of six quadruples with two sets of eclipses that have the 2+2 architecture. These so-called doubly eclipsing systems still present a quite rare group of stars. We collected all available photometric data and carried out a detailed analysis of them. In addition to the precise TESS photometry used to model the light curves for both inner eclipsing binaries, photometric survey data were also used, and more than 100 nights of our own dedicated observations were carried out. These were mainly used for the detection of the long-term evolution of orbital periods. Thanks to these data, …

Solutions For Linear Fractional Differential Equations With Multiple Constraints Using Fractional B-Poly Bases, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis

Physics & Astronomy Faculty Publications

This study presents an innovative numerical method for solving linear fractional differential equations (LFDEs) using modified Bernstein polynomial bases. The proposed approach effectively addresses the challenges posed by the nonlocal nature of fractional derivatives, providing a robust framework for handling multiple initial and boundary value constraints. By integrating the LFDEs and approximating the solutions with modified fractional-order Bernstein polynomials, we derive operational matrices to solve the resulting system numerically. The method’s accuracy is validated through several examples, showing excellent agreement between numerical and exact solutions. Comparative analysis with existing data further confirms the reliability of the approach, with absolute errors …

Click-Ready Gold Nanoparticles From Aqueous Mechanochemistry: 2-Propynylamine As A Reducing Agent And Surface Ligand, Amber L. Garcia, Brian S. Mitchell, Amanda Reusch, Mark J. Fink, Juan P. Hinestroza, Yelin Ko, Julie P. Vanegas

Physics & Astronomy Faculty Publications

We report a rapid aqueous method for synthesizing monodisperse gold nanoparticles (AuNPs), employing 2-propynylamine as both an intrinsic reducing agent and a surface-stabilizing ligand. This self-mediated process—achieved in a single step—yields spherical AuNPs with an average diameter of 4.0 ± 1.0 nm and a well-defined localized surface plasmon resonance band centered at 520 nm. Acting as a bifunctional molecule, 2-propynylamine simultaneously reduces HAuCl4·3H2O to elemental gold and passivates the nanoparticle surface through coordination via the amine group, while preserving a terminal alkyne (–C≡CH) functionality. This reactive moiety remains exposed and chemically accessible, enabling post-synthetic modification through Cu(I)-catalyzed azide–alkyne cycloaddition. Control …

Efficient Parallel Processing Of Second-Generation Tdi Data For Galactic Binaries In Space-Based Gravitational Wave Missions, Xue-Hao Zhang, Soumya D. Mohanty, S. R. Valluri, Shao-Dong Zhao, Qun-Ying Xie, Yu-Xiao Liu

Physics & Astronomy Faculty Publications

Space-based gravitational wave missions such as LISA, Taiji, and Tianqin rely on the time-delay interferometry (TDI) technique to observe low-frequency signals such as Galactic binaries (GBs), massive black-hole binaries, and extreme-mass-ratio inspirals. Among these sources, resolving the large population of GBs poses a central challenge for data analysis. In this work, we present GBSIEVER-C, a pipeline implemented in C and parallelized using OpenMP (Open Multi-Processing), along with a range of additional algorithmic optimizations, including a fast implementation of second-generation TDI response modeling. It builds upon the previous MATLAB-based pipeline that demonstrated competitive performance on LISA Data Challenge (LDC) data. To …

Gw250114: Testing Hawking’S Area Law And The Kerr Nature Of Black Holes, A. G. Abac, I. Abouelfettouh, F. Acernese, Teviet Creighton, Mario C. Diaz, R. Espinosa, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, M. Ramos Arevalo, Wenhui Wang

Physics & Astronomy Faculty Publications

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence of two black holes with near-equal masses m_{1}=33.6_{-0.8}^{+1.2}M_{⊙} and m_{2}=32.2_{-1.3}^{+0.8}M_{⊙}, and small spins χ_{1,2}≤0.26 (90% credibility) and negligible eccentricity e≤0.03. Postmerger data excluding the peak region are consistent with the dominant quadrupolar (ℓ=|m|=2) mode of a Kerr black hole and its first overtone. We constrain the modes' frequencies to ±30% of the Kerr spectrum, providing a test of the remnant's Kerr nature. We also examine Hawking's area law, also known as the second law …

Classifying Compact Radio Emission In Nearby Galaxies: A 10 Ghz Study Of Active Galactic Nuclei, Supernovae, Anomalous Microwave Emission, And Star-Forming Regions, Kristen C. Dage, Eric W. Koch, Evangelia Tremou, Kwangmin Oh, Susmita Sett, Cosima Eibensteiner, Sean T. Linden, Angiraben D. Mahida, Eric J. Murphy, Liliana E. Rivera Sandoval

Physics & Astronomy Faculty Publications

We present 115 compact radio point sources in three galaxies, NGC 5474, NGC 4631, and M51, taken in the most extended (A-)configuration of the Karl G. Jansky Very Large Array at 10 GHz. Several of these compact radio point sources have diffuse counterparts identified in previous multiband studies of resolved radio continuum emission. We find compact counterparts to eight star forming regions, four anomalous microwave emission candidates, and one supernova remnant (SN 2011dh). Nine of the compact radio sources match X-ray counterparts, the majority of which are background galaxies. These AGN are all within the D25 (isophotal diameter) of the …

Development Of A New Ground-Based Instrumentation Technique For Low-Resolution Exoplanet Transmission Spectroscopy, Mary Anne Limbach, Luke M. Schmidt, Ryan J. Oelkers, Darren L. Depoy

Physics & Astronomy Faculty Publications

We present a new instrumentation technique for high-precision, ground-based spectrophotometric measurements ideal for low-resolution (R ∼ 20–60) exoplanet transmission spectroscopy. This technique employs novel thin-film coating technology for wide-band, simultaneous multi-band imaging, enabling high-precision differential photometry through self-referencing and comparison stars. Theoretical calculations and on-sky results show that this method effectively reduces 96% of amplitude scintillation noise and other systematics that typically limit ground-based spectrophotometric precision for bright stars. On-sky results are demonstrated using the custom-built Exoplanet Transmission Spectroscopy Imager (ETSI), deployed at the McDonald Observatory 2.1 m telescope in 2022. For a V = 9.7 mag star, ETSI …

Red Noise Suppression In Pulsar Timing Array Data Using Adaptive Splines, Yi-Qian Qian, Yan Wang, Soumya Mohanty

Physics & Astronomy Faculty Publications

Noise in Pulsar Timing Array (PTA) data is commonly modeled as a mixture of white and red noise components. While the former is related to the receivers, and easily characterized by three parameters (EFAC, EQUAD and ECORR), the latter arises from a mix of hard to model sources and, potentially, a stochastic gravitational wave background (GWB). Since their frequency ranges overlap, GWB search methods must model the non-GWB red noise component in PTA data explicitly, typically as a set of mutually independent Gaussian stationary processes having power-law power spectral densities. However, in searches for continuous wave (CW) signals from resolvable …

Rabi Oscillations And Entanglement Between Two Atoms Interacting By The Rydberg Blockade And With A Quantized Radiation Field Studied By The Jaynes-Cummings Model, Francisco D. Santillan, Andreas Hanke

Physics & Astronomy Faculty Publications

The interaction between atoms and a quantized radiation field is fundamentally important in quantum optics and quantum information science. Due to their unusual properties, Rydberg atoms are promising building blocks for two-qubit gates and atom-light quantum interfaces, exploiting the Rydberg blockade interaction which prevents two atoms at close distance (< 10μm) from being simultaneously excited to Rydberg states. Recently, this effect was used to engineer quantum processors based on arrays of interacting Rydberg atoms illuminated by Raman lasers. Motivated by these experiments, we extend the Jaynes–Cummings model to study the interaction between two Rydberg atoms interacting by the Rydberg blockade and a quantized radiation field. We consider both number (Fock) states of the field and single-mode quantum coherent states. In particular, we discuss different types of entanglements between various components of the total system consisting of the two Rydberg-interacting atoms and coherent states of the field, and show that the behavior is significantly different compared to a system with non-interacting atoms corresponding to the two-atom Tavis-Cummings model. Our results are relevant in view of atom-light quantum interfaces as components for future long-distance quantum communication.

The Vvv Near-Ir Galaxy Catalogue Of The Southern Galactic Disc, M. V. Alonso, L. D. Baravalle, J. L. Nilo-Castellón, C. Villalon, M. Soto, M. A. Sgro, I. V. Daza-Perilla, C. Valotto, M. Lares, Lucas M. Macri

Physics & Astronomy Faculty Publications

Context. The distribution of galaxies in the zone of avoidance (ZoA) is incomplete due to the presence of our own Galaxy.

Aims. Our research is focussed on the identification and characterisation of galaxies in the ZoA, using the new near-infrared (NIR) data from the VVVX survey in regions covering the southern Galactic disc (230° <  l <  350°).

Methods. We used our previously established procedure, based on photometric and morphological criteria, to identify galaxies. The large data volume collected by the VVVX required alternatives to visual inspection, including artificial intelligence techniques such as classifiers based on neural networks.

Results. The VVV NIR galaxy …

Development Of A New Groundbased Instrumentation Technique For Low-Resolution Exoplanet Transmission Spectroscopy, Mary Anne Limbach, Luke M. Schmidt, Ryan J. Oelkers, Darren L. Depoy

Physics & Astronomy Faculty Publications

We present a new instrumentation technique for high-precision, ground-based spectrophotometric measurements ideal for low-resolution (R ∼ 20–60) exoplanet transmission spectroscopy. This technique employs novel thin-film coating technology for wide-band, simultaneous multi-band imaging, enabling high-precision differential photometry through self-referencing and comparison stars. Theoretical calculations and on-sky results show that this method effectively reduces 96% of amplitude scintillation noise and other systematics that typically limit ground-based spectrophotometric precision for bright stars. On-sky results are demonstrated using the custom-built Exoplanet Transmission Spectroscopy Imager (ETSI), deployed at the McDonald Observatory 2.1 m telescope in 2022. For a V = 9.7 mag star, ETSI …

Thermally Tunable Mid-Infrared Nanocavity Resonance Of Coupled Surface Plasmon-Phonon Polaritons, Satya R. Kachiraju, Zachary M. Brown, Sundar Kunwar, Long Chang, Imtiaz Ahmad, Pinku Roy, Vladimir Kuryatkov, Yejin Kwon, Ayrton A. Bernussi, Chase T. Ellis

Physics & Astronomy Faculty Publications

Phase-change materials (PCMs) are essential for achieving tunability of metasurfaces. However, they frequently face limitations in the long-wave infrared range because of their lossy behavior. Here, we experimentally demonstrate a thermally tunable mid-infrared nanocavity resonance from coupled surface plasmon-phonon polaritons that are supported within a trilayer structure of metal-PCM layer-polar dielectric (Au-VO2-SiC). The top metal structures configure the Fabry-Perot cavity resonance near 840 cm−1 (11.9 µm), which is sensitively tunable and reversible with small changes in the VO2 refractive index ∆n near below its insulator-to-metal phase transition temperature where the loss is small. The maximum resonance shift of 7.7 cm−1 …

Estimating Galactic Structure Using Galactic Binaries Resolved By Space-Based Gravitational Wave Observatories, Shao-Dong Zhao, Xue-Hao Zhang, Soumya Mohanty, Màrius Josep Fullana I Alfonso, Yu-Xiao Liu, Qung-Ying Xie

Physics & Astronomy Faculty Publications

Space-based gravitational wave detectors, such as the Laser Interferometer Space Antenna (LISA) and Taiji, will observe GWs from O(108) galactic binary systems, allowing a completely unobscured view of the Milky Way structure. While previous studies have established theoretical expectations based on idealized data-analysis methods that use the true catalog of sources, we present an end-to-end analysis pipeline for inferring galactic structure parameters based on the detector output alone. We employ the GBSIEVER algorithm to extract GB signals from LISA Data Challenge data and develop a maximum likelihood approach to estimate a bulge-disk galactic model using the resolved GBs. We introduce …

Thermally Tunable Mid-Infrared Nanocavity Resonance Of Coupled Surface Plasmon-Phonon Polaritons, Satya R. Kachiraju, Zachary M. Brown, Sundar Kunwar, Long Chang, Imtiaz Ahmad, Pinku Roy, Vladimir Kuryatkov, Yejin Kwon, Ayrton A. Bernussi, Chase T. Ellis

Physics & Astronomy Faculty Publications

Phase-change materials (PCMs) are essential for achieving tunability of metasurfaces. However, they frequently face limitations in the long-wave infrared range because of their lossy behavior. Here, we experimentally demonstrate a thermally tunable mid-infrared nanocavity resonance from coupled surface plasmon-phonon polaritons that are supported within a trilayer structure of metal-PCM layer-polar dielectric (Au-VO2-SiC). The top metal structures configure the Fabry-Perot cavity resonance near 840 cm−1 (11.9 µm), which is sensitively tunable and reversible with small changes in the VO2 refractive index ∆n near below its insulator-to-metal phase transition temperature where the loss is small. The maximum resonance shift of 7.7 cm−1 …

A Wide-Field Map Of Ultracompact Dwarfs In The Coma Cluster, Richard T. Pomeroy, Juan P. Madrid, Conor R. O’Neill, Alexander T. Gagliano

Physics & Astronomy Faculty Publications

A data set of 23,351 globular clusters (GCs) and ultracompact dwarfs (UCDs) in the Coma cluster of galaxies was built using Hubble Space Telescope Advanced Camera for Surveys data. Based on the standard magnitude cut of MV ≤ −11, a total of 523 UCD candidates are found within this data set of compact stellar systems (CSS). From a color–magnitude diagram analysis built using this catalog, we find a clear mass–magnitude relation extending marginally into the UCD parameter space. The luminosity function defined by this data set shows an excess of sources at bright magnitudes, suggesting a bimodal formation scenario …

Hot Donors In Cataclysmic Variables: The Case Of Ei Psc, Jan Kára, S. Zharikov, M. Wolf, N. Vaidman, A. Agishev, S. Khokhlov, C. E. Chavez

Physics & Astronomy Faculty Publications

Context. We present results of time-resolved optical spectroscopy and photometry of the short-orbital period dwarf nova EI Psc.

Aims. This study aims to determine fundamental system parameters of EI Psc, study properties of accretion structures in the system, and investigate its origin and current evolution state.

Methods. We analyse newly obtained time-resolved spectroscopic and photometric observations as well as archival data. We used light curve modelling, Doppler tomography, and MESA evolutionary models to study the characteristics of EI Psc.

Results. The system contains a relatively low temperature (T_eff = 6130 K) white dwarf with mass of M …

Physical And Chemical Characterization Of Recycled Glass Sand For Environmental Restoration, Shehbaz Ahmad, Julie P. Vanegas, Nicholas Borne, Natalia Butler, Toby Mendels, Leah A. Michaeloff, Diego Molina, Mary Salvaggio, Samantha Tamayo, Franziska Trautmann

Physics & Astronomy Faculty Publications

Introduction

We rely on coastal resources for food, water, and energy. However, over 75% of U.S. coastlines are eroding. Concurrently, the U.S. recycles less glass than other developed countries, landfilling hundreds of millions of tons every year. Recycled glass sand has many potential benefits over natural sand for combatting land loss; for example, it can be produced with controlled particle size to better resist erosion, making it an excellent—and underutilized—material for environmental restoration.

Objectives

This research compares the physical and chemical properties of recycled glass sand to natural sands (beach and dredge) from the U.S. Gulf Coast to assess environmental …