Digital Commons Network^™

The Role Of Secondary And Tertiary Structure In The Cap-Independent Translation Of Fgf-9 And Hif-1-Alpha, Amanda Michelle Whittaker

Dissertations, Theses, and Capstone Projects

Under normoxic conditions, eukaryotes initiate translation of RNA through eIF4E recognition of the 5’ cap. However, under cellular stress, eukaryotic translation must be initiated through a 4E-independent, or “cap-independent” mechanism, involving eukaryotic initiation factor 4G (eIF4G) binding directly to the 5’ untranslated regions (5’ UTR) of the RNA. eIF4G binding then recruits the ribosome to the transcript. While this mechanism is useful for translation of apoptotic transcripts and transcripts involved in cell survival, cap-independent translation is also utilized by oncogenic RNA for tumorigenesis. Previous work by our lab and others has categorized this recruitment and initiation mechanism as either internal-ribosome-entry-site …

Taming Biological Complexity Through The Use Of Symmetries, Luis A. Álvarez-García

Dissertations, Theses, and Capstone Projects

The study of biological systems is, inherently, the study of very complex systems. This is essentially due to the fact that they are made up of numerous, often very complicated, interactions between an extensive number of components. Often necessitating an abundance of quantitative parameters and details for a precise description. The human brain for ex- ample, consisting of ∼ 80 billion neurons with ∼ 800 to 100 trillion connections between them, each of them depending on a large set of parameters. Even simpler examples such as bacterial organisms, such as E. coli and B. subtilis, which we focus on …

Novel Alchemical Methodologies For Modeling Molecular Binding, Solmaz Azimi

Dissertations, Theses, and Capstone Projects

Molecular recognition is fundamental to all biological and biochemical processes. Understanding the interactions between molecules is the foundation for drug discovery and development, for understanding biological processes, and for the design of biosensors and nanomaterials. There is tremendous interest in the development of computer models to predict molecular association equilibria. In structure-based drug discovery enterprises, predicting the strength and selectivity of a small molecule to a biological target can advance target identification, aid ligand design, and accelerate high-throughput screening of drug compounds. This work focuses on free energy models, a class of computational methodologies grounded on the fundamental physical and …

Silver-Alloyed Cigs Thin-Film Solar Cells On Flexible Stainless-Steel Substrate, Zhi Huang

Dissertations, Theses, and Capstone Projects

Our dissertation demonstrates the optimization of ACIGS (Ag-Cu-In-Ga-Se) thin-film solar cells, achieving an efficiency of 20.4% through the combined effects of silver incorporation and alkali metal post-deposition treatment (PDT). The incorporation of 2.8% Ag into the CIGS lattice enhanced crystal quality, reduced disorder, and widened the bandgap by 0.103 eV, as evidenced by a significant reduction in Urbach energy. These improvements resulted in stronger light absorption, increased carrier generation, and enhanced photovoltaic parameters, including a short-circuit current density Jsc of 35.31 mA/cm², an open-circuit voltage Voc of 0.74 V, and a fill factor (FF) of 75.8%. PDT using rubidium fluoride …

Controlling Structural Phases Of Sn Through Lattice Engineering, Chandima Kasun Edirisinghe, Anjali Rathore, Taegeon Lee, Daekwon Lee, An Hsi Chen, Garrett Baucom, Eitan Hershkovitz, Anuradha Wijesinghe, Pradip Adhikari, Sinchul Yeom, Hong Seok Lee, Hyung Kook Choi, Hyunsoo Kim, Mina Yoon

Physics Faculty Research & Creative Works

Topology and superconductivity, two distinct phenomena, offer unique insight into quantum properties and their applications in quantum technologies, spintronics, and sustainable energy technologies. Tin (Sn) plays a pivotal role here as an element because of its two structural phases, α-Sn exhibiting topological characteristics and β-Sn showing superconductivity. Here, we demonstrate precise control of these phases in Sn thin films using molecular beam epitaxy with systematically varied lattice parameters of the buffer layer. The Sn films exhibit either β-Sn or α-Sn phases as the buffer layer's lattice constant varies from 6.10Å to 6.48Å, spanning the range from GaSb (like InAs) to …

Underlying Mechanisms Of Quantum Emission In Hexagonal Boron Nitride, Enrique Alejandro Mejia Iv

Dissertations, Theses, and Capstone Projects

Quantum emitters in hexagonal boron nitride (hBN) have emerged as promising candidates for advancing numerous quantum technologies. Visible-spectrum quantum emitters, in particular, have gained significant attention due to their exceptional properties, including high brightness, observable spin structure, and highly tunable emission wavelengths. However, several challenges hold back the practical implementation of hBN-based quantum emitters in technological applications—namely, the unknown physical structure of the emitters, susceptibility to spectral wandering and blinking, and limited understanding of how to control their broad spectral distribution.

In this dissertation, we investigate the collective properties of highly defective hBN. To address the key challenges, we develop …

Leveraging Collective Impact To Characterize And Identify Solutions To Cultural Challenges Within Scientific Societies, Taylor Lightner, Simone B. Soso, Candice M. Etson, Robin Mc C. Greenler, Mercy Mugo, Verónica A. Segarra

Physics: Faculty Publications

A consortium of scientific societies recently identified challenges to inclusivity within the biology communities they represent. Specifically, societies encounter difficulties collecting member demographic data effectively, integrating scientists at transitional career stages, and diversifying their leadership. In response, the Leveraging, Enhancing, and Developing Biology (LED-BIO) research coordination network (NSF 2134725) organized two meetings at the Marine Biological Laboratory in Woods Hole, MA to gather stakeholders and employ top-down and bottom-up organizational approaches to address these challenges. These meetings included Town Hall and Think Tank events to facilitate open dialogue and gather feedback on policies and programs from national organizations in attendance. …

Offshore Wind Farms Could Impact Coastal Marine Heatwaves In Eastern Boundary Upwelling Systems, Michael Dalsin, Ryan K. Walter, Piero L.F. Mazzini

Physics

Analysis of ecosystem impacts from offshore wind (OSW) farm development has primarily focused on localized effects. However, in Eastern Boundary Current Upwelling Systems (EBUS) like the California Current, OSW farms can modify the intensity and spatial structure of wind-driven upwelling, inducing non-local (tens of kms away) changes to seawater temperature. Recent numerical modeling research determined that a hypothetical upper bound full buildout of OSW farms in central California could warm coastal waters through a reduction in upwelling. Here, we examine the sensitivity of coastal marine heatwaves (MHWs), which are prolonged extreme seawater temperatures that are among the greatest threats to …

Anderson Transition For Light In A Three-Dimensional Random Medium, Alexey Yamilov, Hui Cao, Sergey E. Skipetrov

Physics Faculty Research & Creative Works

We study Anderson transition for light in three dimensions by performing large-scale simulations of electromagnetic wave transport in disordered ensembles of perfect-electric-conducting spatially overlapping spheres. A mobility edge that separates diffusive transport and Anderson localization is identified, revealing a sharp transition from diffusion to localization for light. Critical behavior in the vicinity of the mobility edge is well described by a single parameter scaling law. The critical exponent is found to be consistent with the value known for the Anderson transition of the orthogonal universality class. Statistical distribution of total transmission at the mobility edge is described without any fit …

An Effective Secure Multi-Objective Task Scheduling Algorithm In Multi-Cloud Environment, V K S K Sai Vadapalli, Ramesh Babu Gurujukota, Phaneendra Varma Chintalapati, Satyanarayana Murty, G. Sai Chaitanya Kumar, Satish Kumar Kode

Karbala International Journal of Modern Science

In cloud environments, task scheduling is essential for improving performance. Nevertheless, the existence of several heterogeneous clouds makes scheduling extremely difficult, requiring increasingly advanced algorithms to manage these environments' diversity and dynamic nature. To solve this, numerous authors have created a variety of task schedulers utilizing heuristic and metaheuristic techniques. Nevertheless, it remains dynamic and challenging because task scheduling is an NP-hard issue. Furthermore, in many complicated situations, it is still problematic to guarantee security throughout the task’s execution. Therefore, this paper introduces a multi-objective security-aware task scheduler using the Crayfish Mud Ring Optimization Algorithm for a multi-cloud environment. This …

Carbon And Iron Deficiencies In Quiescent Galaxies At Z = 1-3 From Jwst-Suspense: Implications For The Formation Histories Of Massive Galaxies, Aliza G. Beverage, Martje Slob, Mariska Kriek, Charlie Conroy, Guillermo Barro, Rachel Bezanson, Gabriel Brammer, Chloe M. Cheng, Anna De Graaff, Natascha M. Förster Schreiber, Marijn Franx, Brian Lorenz, Pavel E. Mancera Piña, Danilo Marchesini, Adam Muzzin, Andrew B. Newman, Sedona H. Price, Alice E. Shapley, Mauro Stefanon, Katherine A. Suess, Pieter Van Dokkum

Pacific Faculty Work

We present the stellar metallicities and multielement abundances (C, Mg, Si, Ca, Ti, Cr, and Fe) of 15 massive (log M/M⊙ = 10.2-11.2) quiescent galaxies at z = 1-3, derived from ultradeep JWST-SUSPENSE spectra. Compared to quiescent galaxies at z ∼ 0, these galaxies exhibit a deficiency of 0.26 ± 0.04 dex in [C/H], 0.16 ± 0.03 dex in [Fe/H], and 0.07 ± 0.04 dex in [Mg/H], implying rapid formation and quenching before significant enrichment from asymptotic giant branch stars and Type Ia supernovae. Additionally, we find that galaxies forming at higher redshift consistently show higher [Mg/Fe] and lower [Fe/H] …

3F4 Hypergeometric Functions As A Sum Of A Product Of 1F2 Functions, Jack C. Straton

Physics Faculty Publications and Presentations

This paper shows that certain ₃F₄ hypergeometric functions can be expanded in sums of pair products of ₁F₂ functions. In special cases, the ₃F₄ hypergeometric functions reduce to ₂F₃ functions. Further special cases allow one to reduce the ₂F₃ functions to ₁F₂ functions, and the sums to products of ₀F₁ (Bessel) and ₁F₂ functions. The class of hypergeometric functions with summation theorems are thereby expanded beyond those expressible as pair-products of ₂F₁ functions, ₃F₂ functions, and generalized Whittaker functions, into …

Photogalvanic Shift Currents In Bifeo3-Lafeo3 Superlattices, Francesco Delodovici, Charles Paillard

Physics Faculty Publications and Presentations

Designing materials with a controlled photovoltaic response may lead to improved solar cells or photosensors. In this regard, ferroelectric superlattices have emerged as a rich platform to engineer functional properties. In addition, ferroelectrics are naturally endowed with a bulk photovoltaic response stemming from nonthermalized photoexcited carriers, which can overcome the fundamental limits of current solar cells. Yet, their photovoltaic output has been limited by poor optical absorption and poor charge collection or photoexcited carrier mean free path. We use Density Functional Theory and Wannierization to compute the so-called Bulk Photovoltaic shift current and the optical properties of BiFeO3/LaFeO3 superlattices. We …

Breaking Barriers: Investigating Gender Dynamics In Introductory Physics Lab Classes, Bilas Paul, Shantanu Chakraborty, Ganga Sharma

Georgia Journal of Science

The persistent underrepresentation of women and other gender minorities in physical science fields has been an ongoing concern. This study investigates gender dynamics in introductory physics laboratory courses, focusing on whether students of different gender identities exhibit equal inclination and confidence in conducting lab experiments, and whether they face barriers that impact their participation. Conducted across three institutions and involving non-physics STEM students enrolled in algebra-based and calculus-based physics courses, the study found mixed results, with two institutions showing no significant gender-based differences in participation levels during lab activities, while one institution demonstrated significant differences. Chi-square tests revealed no significant …

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

Michigan Tech Publications

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

Single-Molecule Dna-Flow Stretching Assay As A Versatile Hybrid Tool For Investigating Dna-Protein Interactions, Sadaf Shehzad, Hyeongjun Kim

Physics & Astronomy Faculty Publications

Single-molecule techniques allow researchers to investigate individual molecules and obtain unprecedented details of the heterogeneous nature of biological entities. They play instrumental roles in studying DNA-protein interactions due to the ability to visualize DNA or proteins and to manipulate individual DNA molecules by applying force or torque. Here, we describe single-molecule DNA-flow stretching assays as hybrid tools that combine forces with fluorescence. We also review how widely these assays are utilized in elucidating working mechanisms of DNA-binding proteins. Additionally, we provide a brief explanation of various efforts to prepare DNA substrates with desired internal protein-binding sequences. More complicated needs for …

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

Faculty Publications

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

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

Physics & Astronomy Faculty Publications

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

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

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

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

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

Karbala International Journal of Modern Science

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

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

Al-Bahir

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

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

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

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

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

Michigan Tech Publications

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

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

Georgia Journal of Science

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

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

Physics & Astronomy Faculty Works

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

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

Physics & Astronomy Faculty Publications

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

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

Pacific Faculty Work

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

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

Physics Faculty Research & Creative Works

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

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

Michigan Tech Publications

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

Thermal Noise Measurement Below The Standard Quantum Limit, Ronald Pagano

LSU Doctoral Dissertations

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