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Articles 151 - 180 of 20779

Full-Text Articles in Physics

Ultradeep Atca Imaging Of 47 Tucanae Reveals A Central Compact Radio Source, Alessandro Paduano, Arash Bahramian, James C. A. Miller-Jones, Adela Kawka, Tim J. Galvin, Liliana E. Rivera Sandoval, Sebastian Kamann, Jay Strader, Laura Chomiuk, Craig O. Heinke Jan 2024

Ultradeep Atca Imaging Of 47 Tucanae Reveals A Central Compact Radio Source, Alessandro Paduano, Arash Bahramian, James C. A. Miller-Jones, Adela Kawka, Tim J. Galvin, Liliana E. Rivera Sandoval, Sebastian Kamann, Jay Strader, Laura Chomiuk, Craig O. Heinke

Physics and Astronomy Faculty Publications and Presentations

We present the results of an ultradeep radio continuum survey, containing ∼480 hr of observations, of the Galactic globular cluster 47 Tucanae with the Australia Telescope Compact Array. This comprehensive coverage of the cluster allows us to reach rms noise levels of 1.19 μJy beam−1 at 5.5 GHz, 940 nJy beam−1 at 9 GHz, and 790 nJy beam−1 in a stacked 7.25 GHz image. This is the deepest radio image of a globular cluster and the deepest image ever made with the Australia Telescope Compact Array. We identify ATCA J002405.702-720452.361, a faint (6.3 ± 1.2 μJy at 5.5 …

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Detection And Diagnosis Of Bacterial Pathogens In Blood Using Laser-Induced Breakdown Spectroscopy, E J. Blanchette, E A. Tracey, A Baughan, G E. Johnson, H Malik, C N. Alionte, I G. Arthur, M E. Pontoni, Steven Rehse Jan 2024

Detection And Diagnosis Of Bacterial Pathogens In Blood Using Laser-Induced Breakdown Spectroscopy, E J. Blanchette, E A. Tracey, A Baughan, G E. Johnson, H Malik, C N. Alionte, I G. Arthur, M E. Pontoni, Steven Rehse

Physics Publications

The ability to rapidly and accurately detect and identify pathogenic bacteria in clinically-obtained blood specimens with laser-induced breakdown spectroscopy (LIBS) is evaluated. Samples of blood obtained from five patients in a local hospital were confirmed to be negative for the presence of bacteria by the pathology department and were then tested with LIBS. Specimens of blood were tested as obtained from the hospital with no other alteration as control samples and were also intentionally spiked with known aliquots of Escherichia coli, Staphylococcus aureus, Enterobacter cloacae, and Pseudomonas aeruginosa to simulate blood infections. LIBS spectra were acquired from blood deposited on …

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Detection And Diagnosis Of Bacterial Pathogens In Urine Using Laser-Induced Breakdown Spectroscopy, E J. Blanchette, E A. Tracey, A Baughan, G E. Johnson, H Malik, C N. Alionte, I G. Arthur, M E. Potoni, Steven Rehse Jan 2024

Detection And Diagnosis Of Bacterial Pathogens In Urine Using Laser-Induced Breakdown Spectroscopy, E J. Blanchette, E A. Tracey, A Baughan, G E. Johnson, H Malik, C N. Alionte, I G. Arthur, M E. Potoni, Steven Rehse

Physics Publications

The presence of bacterial cells from three species has been detected in clinical specimens of human urine using laser-induced breakdown spectroscopy (LIBS) by using a partial least squares discriminant analysis (PLS-DA) of 360 spectra obtained from 12 specimens of infected urine and 239 spectra obtained from eight specimens of sterile urine. Nominally sterile urine specimens obtained from four patients at a local hospital after being screened negative for the presence of bacterial pathogens were spiked with known aliquots of Escherichia coli, Staphylococcus aureus, and Enterobacter cloacae to simulate clinical urinary tract infections. Fifteen emission line intensities measured from the LIBS …

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Compton Scattering Of Mammographic Soft X-Ray Beams By Alkali And Transition Metal Salt Filters Produce X-Ray Interference Zones That May Have Treatment Potential For Localized Cancer Lesions, Subhendra N. Sarkar, Eric Lobel, Sabina Rakhmatova, Derbie Desir, Somdat Kissoon, Daler Djuraev, Katie Tam Jan 2024

Compton Scattering Of Mammographic Soft X-Ray Beams By Alkali And Transition Metal Salt Filters Produce X-Ray Interference Zones That May Have Treatment Potential For Localized Cancer Lesions, Subhendra N. Sarkar, Eric Lobel, Sabina Rakhmatova, Derbie Desir, Somdat Kissoon, Daler Djuraev, Katie Tam

Publications and Research

In breast x-ray imaging scattered radiation adds 50% of harmful radiation dose from anisotropic Compton scattering mechanism. We have been working with double layered inorganic salt materials that can induce Compton scattering to the incident mammographic x ray beams (in 20-30 kVp range) with adequate isotropy (angular control). Typically metal nitrates and alkali halide salt layers are shown here to cause low energy radiation interference zones with high and low photon intensities and local flux heterogeneity in terms of flux covariance. Spatial variation of low energy photon flux creates concentrated and sparse radiation zones that may be used to induce …

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Revisiting The Divergent Multipole Expansion Of Atom-Surface Interactions: Hydrogen And Positronium, Α -Quartz, And Physisorption, Ulrich D. Jentschura Jan 2024

Revisiting The Divergent Multipole Expansion Of Atom-Surface Interactions: Hydrogen And Positronium, Α -Quartz, And Physisorption, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We revisit the derivation of multipole contributions to the atom-wall interaction previously presented in Łach et al. [G. Łach, M. DeKieviet, and U. D. Jentschura, Phys. Rev. A 81, 052507 (2010)10.1103/PhysRevA.81.052507]. A careful reconsideration of the angular momentum decomposition of the second-, third-, and fourth-rank tensors composed of the derivatives of the electric-field modes leads to a modification for the results for the quadrupole, octupole, and hexadecupole contributions to the atom-wall interaction. Asymptotic results are given for the asymptotic long-range forms of the multipole terms, in both the short-range and long-range limits. Calculations are carried out for hydrogen and positronium …

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Two-Center And Path Interference In Dissociative Capture In P+ H2 Collisions, S. Bastola, M. Dhital, B. Lamichhane, A. Silvus, R. Lomsadze, A. Hasan, A. Igarashi, Michael Schulz Jan 2024

Two-Center And Path Interference In Dissociative Capture In P+ H2 Collisions, S. Bastola, M. Dhital, B. Lamichhane, A. Silvus, R. Lomsadze, A. Hasan, A. Igarashi, Michael Schulz

Physics Faculty Research & Creative Works

We have measured and calculated fully differential cross sections (FDCS) for dissociative capture in 75-keV p+H2 collisions. FDCS were analyzed in the kinetic energy release (KER) ranges 0 to 2.1 eV and 4 to 7 eV for two different molecular orientations. In the latter range, dissociation is dominated by electronic excitation to the 2pπu state. Here, we observed two-center interference for an orientation in the plane perpendicular to the initial beam axis and parallel to the transverse momentum transfer. The interference pattern is afflicted with a constant phase shift of π. In the range KER=0 to 2.1 eV, dissociation is …

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Spectrum And Quench-Induced Dynamics Of Spin-Orbit-Coupled Quantum Droplets, Sonali Gangwar, Rajamanickam Ravisankar, S. (Simeon) I. Mistakidis, Paulsamy Muruganandam, Pankaj Kumar Mishra Jan 2024

Spectrum And Quench-Induced Dynamics Of Spin-Orbit-Coupled Quantum Droplets, Sonali Gangwar, Rajamanickam Ravisankar, S. (Simeon) I. Mistakidis, Paulsamy Muruganandam, Pankaj Kumar Mishra

Physics Faculty Research & Creative Works

We investigate the ground state and dynamics of one-dimensional spin-orbit coupled (SOC) quantum droplets within the extended Gross-Pitaevskii approach. As the SOC wave number increases, stripe droplet patterns emerge, with a flat-top background, for larger particle numbers. The surface energy decays following a power-law with respect to the interactions. At small SOC wave numbers, a transition from Gaussian to flat-top droplets occurs for either a larger number of atoms or reduced intercomponent attraction. The excitation spectrum shows that droplets for relatively small SOC wave numbers are stable, otherwise stripe droplets feature instabilities as a function of the particle number or …

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Accelerating Markov Chain Monte Carlo Sampling With Diffusion Models, N. T. Hunt-Smith, W. Melnitchouk, F. Ringer, N. Sato, A. W. Thomas, M. J. White Jan 2024

Accelerating Markov Chain Monte Carlo Sampling With Diffusion Models, N. T. Hunt-Smith, W. Melnitchouk, F. Ringer, N. Sato, A. W. Thomas, M. J. White

Physics Faculty Publications

Global fits of physics models require efficient methods for exploring high-dimensional and/or multimodal posterior functions. We introduce a novel method for accelerating Markov Chain Monte Carlo (MCMC) sampling by pairing a Metropolis-Hastings algorithm with a diffusion model that can draw global samples with the aim of approximating the posterior. We briefly review diffusion models in the context of image synthesis before providing a streamlined diffusion model tailored towards low-dimensional data arrays. We then present our adapted Metropolis-Hastings algorithm which combines local proposals with global proposals taken from a diffusion model that is regularly trained on the samples produced during the …

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Beam Spin Asymmetry Measurements Of Deeply Virtual Π⁰ Production With Clas12, The Clas Collaboration, A. Kim, S. Diehl, K. Joo, V. Kubarovsky, P. Achenbach, Z. Akbar, J. S. Alvarado, Whitney R. Armstrong, H. Atac, H. Avakian, C. Ayerbe Gayoso, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, A. Bianconi, A. S. Biselli, M. Bondi, M. Zureck, Et Al. Jan 2024

Beam Spin Asymmetry Measurements Of Deeply Virtual Π⁰ Production With Clas12, The Clas Collaboration, A. Kim, S. Diehl, K. Joo, V. Kubarovsky, P. Achenbach, Z. Akbar, J. S. Alvarado, Whitney R. Armstrong, H. Atac, H. Avakian, C. Ayerbe Gayoso, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, A. Bianconi, A. S. Biselli, M. Bondi, M. Zureck, Et Al.

Physics Faculty Publications

The new experimental measurements of beam spin asymmetry were performed for the deeply virtual exclusive π0 production in a wide kinematic region with the photon virtualities Q2 up to 6.6 GeV2and the Bjorken scaling variable 𝓍B in the valence regime. The data were collected by the CEBAF Large Acceptance Spectrometer (CLAS12) at Jefferson Lab with longitudinally polarized 10.6 GeV electrons scattered on an unpolarized liquid-hydrogen target. Sizable asymmetry values indicate a substantial contribution from transverse virtual photon amplitudes to the polarized structure functions. The interpretation of these measurements in terms of the Generalized Parton Distributions …

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Gluon Helicity From Global Analysis Of Experimental Data And Lattice Qcd Ioffe Time Distributions, J. Karpie, R. M. Whitehill, W. Melnitchouk, C. Monahan, K. Orginos, J.-W. Qui, D. G. Richards, N. Sato, S. Zafeiropoulos, Jefferson Lab Angular Momentum And Hadstruc Collaboration Jan 2024

Gluon Helicity From Global Analysis Of Experimental Data And Lattice Qcd Ioffe Time Distributions, J. Karpie, R. M. Whitehill, W. Melnitchouk, C. Monahan, K. Orginos, J.-W. Qui, D. G. Richards, N. Sato, S. Zafeiropoulos, Jefferson Lab Angular Momentum And Hadstruc Collaboration

Physics Faculty Publications

We perform a new global analysis of spin-dependent parton distribution functions with the inclusion of Ioffe time pseudodistributions computed in lattice QCD (LQCD), which are directly sensitive to the gluon helicity distribution, Δg. These lattice data have an analogous relationship to parton distributions as do experimental cross sections, and can be readily included in global analyses. We focus in particular on the constraining capability of current LQCD data on the sign of Δg at intermediate parton momentum fractions x, which was recently brought into question by analysis of data in the absence of parton positivity constraints. …

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Quantum Logic Control And Precision Measurements Of Molecular Ions In A Ring Trap: An Approach For Testing Fundamental Symmetries, Yan Zhou, Joshua O. Island, Matt Grau Jan 2024

Quantum Logic Control And Precision Measurements Of Molecular Ions In A Ring Trap: An Approach For Testing Fundamental Symmetries, Yan Zhou, Joshua O. Island, Matt Grau

Physics Faculty Publications

This paper presents an experimental platform designed to facilitate quantum logic control of polar molecular ions in a segmented ring ion trap, paving the way for precision measurements. This approach focuses on achieving near-unity state preparation and detection, as well as long spin-precession coherence. A distinctive aspect lies in separating state preparation and detection conducted in a static frame from parity-selective spin precession in a rotating frame. Moreover, the method is designed to support spatially and temporally coincident measurements on multiple ions prepared in states with different sensitivity to the new physics of interest. This provides powerful techniques to probe …

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Evolution Of Efimov States, Sebastian M. Dawid, Md Habib E. Islam, Raúl A. Briceño, Andrew W. Jackura Jan 2024

Evolution Of Efimov States, Sebastian M. Dawid, Md Habib E. Islam, Raúl A. Briceño, Andrew W. Jackura

Physics Faculty Publications

The Efimov phenomenon manifests itself as an emergent discrete scaling symmetry in the quantum three-body problem. In the unitarity limit, it leads to an infinite tower of three-body bound states with energies forming a geometric sequence. In this work, we study the evolution of these so-called Efimov states using relativistic scattering theory. We identify them as poles of the three-particle 𝑆 matrix in the complex energy plane, and we study how they transform from virtual states through bound states to resonances when we change the interaction strength. We dial the scattering parameters toward the unitarity limit and observe the emergence …

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Novel Measurement Of The Neutron Magnetic Form Factor From A=3 Mirror Nuclei, S. N. Sentiesteban, S. Li, D. Abrams, S. Alsalmi, D. Androic, K. Aniol, J. Arrington, T. Averett, C. Ayerbe Gayoso, J. Bane, S. Barcus, J. Barrow, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, A. Camsonne, J. Castellanos, J. Chen, J. P. Chen, D. Chrisman, M. E. Christy, C. Clarke, S. Covrig, R. Cruz-Torres, D. Day, D. Dutta, E. Fuchey, C. Gal, F. Garibaldi, T. N. Gautam, T. Gogami, J. Gomez, P. Guèye, T. J. Hague, J. O. Hansen, F. Hauenstein, W. Henry, D. W. Higinbotham, R. J. Holt, C. Hyde, K. Itabashi, M. Kaneta, A. Karki, A. T. Katramatou, C. E. Keppel, P. M. King, L. Kurbany, T. Kutz, N. Lashley-Colthirst, W. B. Li, H. Liu, N. Liyange, E. Long, A. Lovato, J. Mammei, P. Markowitz, R. E. Mcclellan, F. Meddi, D. Meekins, R. Michaels, M. Mihovilovič, A. Moyer, S. Nagao, D. Nguyen, M. Nycz, M. Olson, L. Ou, V. Owen, C. Palatchi, B. Pandey, A. Papadopoulou, S. Park, T. Petkovic, S. Premathilake, V. Punjabi, R. D. Ransome, P. E. Reimer, J. Reinhold, S. Riordan, N. Rocco, V.M. Rodriguez, A. Schmidt, B. Schmookler, E. P. Segarra, A. Shahinyan, S. Širca, K. Slifer, P. Solvignon, T. Su, R. Suleiman, L. Tang, Y. Tian, W. Tireman, F. Tortorici, Y. Toyama, K Uehara, G. M. Urciuoli, D. Votaw, J. Williamson, B. Wojtsekhowski, S. Wood, Z. H. Ye, J. Zhang, X. Zheng Jan 2024

Novel Measurement Of The Neutron Magnetic Form Factor From A=3 Mirror Nuclei, S. N. Sentiesteban, S. Li, D. Abrams, S. Alsalmi, D. Androic, K. Aniol, J. Arrington, T. Averett, C. Ayerbe Gayoso, J. Bane, S. Barcus, J. Barrow, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, A. Camsonne, J. Castellanos, J. Chen, J. P. Chen, D. Chrisman, M. E. Christy, C. Clarke, S. Covrig, R. Cruz-Torres, D. Day, D. Dutta, E. Fuchey, C. Gal, F. Garibaldi, T. N. Gautam, T. Gogami, J. Gomez, P. Guèye, T. J. Hague, J. O. Hansen, F. Hauenstein, W. Henry, D. W. Higinbotham, R. J. Holt, C. Hyde, K. Itabashi, M. Kaneta, A. Karki, A. T. Katramatou, C. E. Keppel, P. M. King, L. Kurbany, T. Kutz, N. Lashley-Colthirst, W. B. Li, H. Liu, N. Liyange, E. Long, A. Lovato, J. Mammei, P. Markowitz, R. E. Mcclellan, F. Meddi, D. Meekins, R. Michaels, M. Mihovilovič, A. Moyer, S. Nagao, D. Nguyen, M. Nycz, M. Olson, L. Ou, V. Owen, C. Palatchi, B. Pandey, A. Papadopoulou, S. Park, T. Petkovic, S. Premathilake, V. Punjabi, R. D. Ransome, P. E. Reimer, J. Reinhold, S. Riordan, N. Rocco, V.M. Rodriguez, A. Schmidt, B. Schmookler, E. P. Segarra, A. Shahinyan, S. Širca, K. Slifer, P. Solvignon, T. Su, R. Suleiman, L. Tang, Y. Tian, W. Tireman, F. Tortorici, Y. Toyama, K Uehara, G. M. Urciuoli, D. Votaw, J. Williamson, B. Wojtsekhowski, S. Wood, Z. H. Ye, J. Zhang, X. Zheng

Physics Faculty Publications

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron’s electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei …

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A = 3(E,E') 𝑥B ≥ 1 Cross-Section Ratios And The Isospin Structure Of Short-Range Correlations, A. Schmidt, A. W. Denniston, E. M. Seroka, N. Barnea, D. W. Higinbotham, I. Korover, G. A. Miller, E. Piasetzky, M. Strikman, L. B. Weinstein, R. Weiss, O. Hen Jan 2024

A = 3(E,E') 𝑥B ≥ 1 Cross-Section Ratios And The Isospin Structure Of Short-Range Correlations, A. Schmidt, A. W. Denniston, E. M. Seroka, N. Barnea, D. W. Higinbotham, I. Korover, G. A. Miller, E. Piasetzky, M. Strikman, L. B. Weinstein, R. Weiss, O. Hen

Physics Faculty Publications

We study the relation between measured high-𝑥𝐵, high-𝑄2, helium-3 to tritium, (𝑒,𝑒′) inclusive-scattering cross-section ratios and the relative abundance of high-momentum neutron-proton (𝑛⁢𝑝) and proton-proton (𝑝⁢𝑝) short-range correlated nucleon pairs in three-body (𝐴=3) nuclei. Analysis of these data using a simple pair-counting cross-section model suggested a much smaller 𝑛⁢𝑝/𝑝⁢𝑝 ratio than previously measured in heavier nuclei, questioning our understanding of 𝐴 = 3 nuclei and, by extension, all other nuclei. Here, we examine this finding using spectral-function-based cross-section calculations, with both an ab initio 𝐴 = 3 spectral function and effective generalized contact formalism spectral functions …

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The Present And Future Of Qcd, P. Achenbach, D. Adhikari, A. Afanasev, F. Afzal, C. A. Aidala, A. Al-Bataineh, D. K. Almaalol, M. Amaryan, D. Androić, W. R. Armstrong, M. Arratia, J. Arrington, A. Asaturyan, E. C. Aschenauer, H. Atac, H. Avakian, T. Averett, C. Ayerbe Gayoso, X. Bai, M. Zurek, Et. Al. Jan 2024

The Present And Future Of Qcd, P. Achenbach, D. Adhikari, A. Afanasev, F. Afzal, C. A. Aidala, A. Al-Bataineh, D. K. Almaalol, M. Amaryan, D. Androić, W. R. Armstrong, M. Arratia, J. Arrington, A. Asaturyan, E. C. Aschenauer, H. Atac, H. Avakian, T. Averett, C. Ayerbe Gayoso, X. Bai, M. Zurek, Et. Al.

Physics Faculty Publications

This White Paper presents an overview of the current status and future perspective of QCD research, based on the community inputs and scientific conclusions from the 2022 Hot and Cold QCD Town Meeting. We present the progress made in the last decade toward a deep understanding of both the fundamental structure of the sub-atomic matter of nucleon and nucleus in cold QCD, and the hot QCD matter in heavy ion collisions. We identify key questions of QCD research and plausible paths to obtaining answers to those questions in the near future, hence defining priorities of our research over the coming …

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Continuous-Variable Quantum Computation Of The O(3) Model In 1+1 Dimensions, Raghav G. Jha, Felix Ringer, George Siopsis, Shane Thompson Jan 2024

Continuous-Variable Quantum Computation Of The O(3) Model In 1+1 Dimensions, Raghav G. Jha, Felix Ringer, George Siopsis, Shane Thompson

Physics Faculty Publications

We formulate the O(3) nonlinear sigma model in 1+1 dimensions as a limit of a three-component scalar field theory restricted to the unit sphere in the large squeezing limit. This allows us to describe the model in terms of the continuous-variable (CV) approach to quantum computing. We construct the ground state and excited states using the coupled-cluster Ansatz and find excellent agreement with the exact diagonalization results for a small number of lattice sites. We then present the simulation protocol for the time evolution of the model using CV gates and obtain numerical results using a photonic quantum simulator. We …

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The Use Of Fluorescence Lifetime Imaging (Flim) For In Situ Microbial Detection In Complex Mineral Substrates, Yekaterina G. Chmykh, Jay Nadeau Jan 2024

The Use Of Fluorescence Lifetime Imaging (Flim) For In Situ Microbial Detection In Complex Mineral Substrates, Yekaterina G. Chmykh, Jay Nadeau

Physics Faculty Publications and Presentations

The utility of fluorescence lifetime imaging microscopy (FLIM) for identifying bacteria in complex mineral matrices was investigated. Baseline signals from unlabelled Bacillus subtilis and Euglena gracilis, and Bacillus subtilis labelled with SYTO 9 were obtained using two-photon excitation at 730, 750 and 800 nm, identifying characteristic lifetimes of photosynthetic pigments, unpigmented cellular autofluorescence, and SYTO 9. Labelled and unlabelled B. subtilis were seeded onto marble and gypsum samples containing endolithic photosynthetic cyanobacteria and the ability to distinguish cells from mineral autofluorescence and nonspecific dye staining was examined in parallel with ordinary multichannel confocal imaging. It was found that FLIM …

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Quest For An Optimal Spin-Polarized Electron Source For The Electron-Ion Collider, J. Biswas, E. Wang, O. Rahman, J. Sharitka, K. Kisslinger, Adam Masters, S. Marsillac, T. Lee Jan 2024

Quest For An Optimal Spin-Polarized Electron Source For The Electron-Ion Collider, J. Biswas, E. Wang, O. Rahman, J. Sharitka, K. Kisslinger, Adam Masters, S. Marsillac, T. Lee

Electrical & Computer Engineering Faculty Publications

Superlattice GaAs photocathodes play a crucial role as the primary source of polarized electrons in various accelerator facilities, including the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson National Laboratory and the Electron-Ion Collider (EIC) at Brookhaven National Laboratory. To increase the quantum efficiency (QE) of GaAs/GaAsP superlattice photocathodes, a Distributed Bragg Reflector (DBR) is grown underneath using metal-organic chemical vapor deposition (MOCVD). There are several challenges associated with DBR photocathodes: the resonance peak may not align with the emission threshold of around 780 nm, non-uniform doping density in the top 5 nm may significantly impact QE and spin polarization, …

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Lithium Tetraborate As A Neutron Scintillation Detector: A Review, Elena Echeverria, John W. Mcclory, Lauren Samson, Katherine Shene, Juan A. Colon Santana, Yaroslav V. Burak, Volodymyr T. Adamiv, Ihor M. Teslyuk, Lu Wang, Wai-Ning Mei, Kyle A. Nelson, Douglas S. Mcgregor, Peter A. Dowben, Carolina C. Ilie, James C. Petrosky, Archit Dhingra Dec 2023

Lithium Tetraborate As A Neutron Scintillation Detector: A Review, Elena Echeverria, John W. Mcclory, Lauren Samson, Katherine Shene, Juan A. Colon Santana, Yaroslav V. Burak, Volodymyr T. Adamiv, Ihor M. Teslyuk, Lu Wang, Wai-Ning Mei, Kyle A. Nelson, Douglas S. Mcgregor, Peter A. Dowben, Carolina C. Ilie, James C. Petrosky, Archit Dhingra

Faculty Publications

The electronic structure and translucent nature of lithium tetraborate (Li2B4O7) render it promising as a scintillator medium for neutron detection applications. The inherently large neutron capture cross-section due to 10B and 6Li isotopes and the ease with which Li2B4O7 can be enriched with these isotopes, combined with the facile inclusion of rare earth dopants (occupying the Li+ sites), are expected to improve the luminescent properties, as well as the neutron detection efficiency, of Li2B4O7. The electronic structure of both doped …

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Beyond Standard Model: Electromagnetic Origin Of Strong Interaction Between Composite Structures Made Of Basic Elementary ±E/3 Charges, Polievkt Perov Dec 2023

Beyond Standard Model: Electromagnetic Origin Of Strong Interaction Between Composite Structures Made Of Basic Elementary ±E/3 Charges, Polievkt Perov

College of Arts & Sciences Faculty Works

Interaction between spinning composite structures of quarks is considered. In simple variants of the quark structures, one basic elementary particle of charge of magnitude |e|/3 is on the axis of rotation and several basic particles of an opposite sign are revolving in the circular orbit about the axis. Each charge in the structure contributes to the electric field and electric potential around the structure. But only revolving basic particles contribute to the spin and to the magnetic moment of the structure. Equations for the axial electric field and the electric potential of each structure at points on its axis are …

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Numerical Study Of Owls' Leading-Edge Serrations, Asif Shahriar Nafi, Nikolaos Beratlis, Elias Balaras, Roi Gurka Dec 2023

Numerical Study Of Owls' Leading-Edge Serrations, Asif Shahriar Nafi, Nikolaos Beratlis, Elias Balaras, Roi Gurka

Physics and Engineering Science

Owls' silent flight is commonly attributed to their special wing morphology combined with wingbeat kinematics. One of these special morphological features is known as the leading-edge serrations: rigid miniature hook-like patterns found at the primaries of the wings' leading-edge. It has been hypothesized that leading-edge serrations function as a passive flow control mechanism, impacting the aerodynamic performance. To elucidate the flow physics associated with owls' leading-edge serrations, we investigate the flow-field characteristic around a barn owl wing with serrated leading-edge geometry positioned at 20° angle of attack for a Reynolds number of 40 000. We use direct numerical simulations, where …

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Physics Ii, Kalani Hettiarachchilage Dec 2023

Physics Ii, Kalani Hettiarachchilage

Open Educational Resources

Physics II, class code PHY 156 at College of Staten Island is the second part of two two-semester algebra-based introductory physics courses. This course overlaps of the following topics laws of electricity, magnetism, optics, and modern physics. The important laws of physics in these areas and problem-solving are emphasized. Problem solving is an integral part of the course, all contents are designed to think critically, analytically, and logically. Conceptual understanding is reinforced using interactive computer-based techniques, demonstrations, problem-solving strategies, and laboratory experiences. In this document, all the class materials including lectures, worksheets, homework, group work assignments, quizzes, and conceptual Slido …

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Physics I, Kalani Hettiarachchilage Dec 2023

Physics I, Kalani Hettiarachchilage

Open Educational Resources

Physics I, class code PHY 116 at College of Staten Island is the first part of a two-semester algebra-based introductory physics course. This course overlaps many topics in the laws of classical mechanics, fluid dynamics, thermodynamics, wave motion, and sound. The important laws of physics in these areas and problem-solving are emphasized. Problem solving is an integral part of the course, all contents are designed to think critically, analytically, and logically. Conceptual understanding is reinforced using interactive computer-based techniques, demonstrations, problem-solving strategies, and laboratory experiences. In this document, all the class materials including lectures, worksheets, homework and group work assignments, …

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Creative Physics Syllabus For Online Class, Kalani Hettiarachchilage Dec 2023

Creative Physics Syllabus For Online Class, Kalani Hettiarachchilage

Open Educational Resources

Creative Physics syllabus for all information and guidelines will be a big help for students to know about the class structure, expectations, submission, personalized class materials, class ethics, and requirements in one place. This detailed syllabus will be a very effective way of expressing the information to the class. Creating a detailed syllabus and engaging activity of in the learning management system such as syllabus review activity will help students to navigate through important items on the syllabus.

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Computing An Image Of Objects Hiding Behind A Black Hole, Shannon Harding Dec 2023

Computing An Image Of Objects Hiding Behind A Black Hole, Shannon Harding

Honors Program Theses and Projects

Gravitational lensing is the bending of light rays around a black hole. The goal of this project was to produce a computer code that would model light rays coming from a grid of objects set behind a rotating black hole. Using these light rays, we produced an image illustrating how this background of objects would appear to an observer on Earth. This was done by creating a MATLAB code to model the paths of multiple light rays at a time. This code was then used to help check and correct a C++ code that produced an image. Over the semester, …

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Studying The Impact Of The Geospace Environment On Solar Lithosphere Coupling And Earthquake Activity, Dimitar Ouzounov, Galina Khachikyan Dec 2023

Studying The Impact Of The Geospace Environment On Solar Lithosphere Coupling And Earthquake Activity, Dimitar Ouzounov, Galina Khachikyan

Mathematics, Physics, and Computer Science Faculty Articles and Research

In solar–terrestrial physics, there is an open question: does a geomagnetic storm affect earthquakes? We expand research in this direction, analyzing the seismic situation after geomagnetic storms (GMs) accompanied by the precipitation of relativistic electrons from the outer radiation belt to form an additional radiation belt (RB) around lower geomagnetic lines. We consider four widely discussed cases in the literature for long-lived (weeks, months) RBs due to GMs and revealed that the 1/GMs 24 March 1991 with a new RB at L~2.6 was followed by an M7.0 earthquake in Alaska, 30 May 1991, near footprint L = 2.69; the 2/GMs …

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Introduction To Physics, Kalani Hetti Dec 2023

Introduction To Physics, Kalani Hetti

Open Educational Resources

Introduction to physics, class code PHY 114 at college of Staten Island covers general physics concepts by using very simple algebraic calculations. Topics may include scientific measurements, significant figures, estimation, units, linear and rotational motion, vectors, forces, energy, momentum, collision, impulse, projectile motion, circular motion, thermodynamics, oscillating waves, electricity and magnetism, properties of lights, reflection, refraction, atomic nuclei, and radioactivity. This course is designed to teach general concepts and laws of physics to everyday life enforcing student’s critical thinking, logical patterns, organization, and everyday life applications. In this document, all the class materials including lectures, worksheets, homework assignments, quizzes, and …

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Novel Integrated Sachs-Wolfe Effect From Early Dark Energy, Tristan L. Smith, J. T. Giblin Jr., M. Amin, M. Gerhardinger, E. Florio, M. Cerep, S. Daniels Dec 2023

Novel Integrated Sachs-Wolfe Effect From Early Dark Energy, Tristan L. Smith, J. T. Giblin Jr., M. Amin, M. Gerhardinger, E. Florio, M. Cerep, S. Daniels

Physics & Astronomy Faculty Works

We study the nonlinear effects of minimally coupled, massless, cosmological scalar fields on the cosmic microwave background (CMB). These fields can exhibit postrecombination parametric resonance and subsequent nonlinear evolution leading to novel contributions to the gravitational potential. We compute the resulting contributions to the CMB temperature anisotropies through the time variation of the gravitational potential (i.e., the integrated Sachs-Wolfe (ISW) effect). We find that fields that constitute 5% of the total energy density and become dynamical at zc ≃ 104 can produce marginally observable ISW signals at multipoles ℓ ≃ 2000. Fields that become dynamical at earlier times …

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Comparative Analysis Of Interacting Stepped Dark Radiation, N. Schöneberg, G. F. Abellán, T. Simon, A. Bartlett, Y. Patel, Tristan L. Smith Dec 2023

Comparative Analysis Of Interacting Stepped Dark Radiation, N. Schöneberg, G. F. Abellán, T. Simon, A. Bartlett, Y. Patel, Tristan L. Smith

Physics & Astronomy Faculty Works

Models that address both the Hubble and S8 tensions with the same mechanism generically cause a prerecombination suppression of the small scale matter power spectrum. Here we focus on two such models. Both models introduce a self-interacting dark radiation fluid scattering with dark matter, which has a step in its abundance around some transition redshift. In one model, the interaction is weak and with all of the dark matter whereas in the other it is strong but with only a fraction of the dark matter. The weakly interacting case is able to address both tensions simultaneously and provide a …

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Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy Dec 2023

Development Of An Optical Test Bed For The Fabrication And Characterisation Of An Analog Holographic Wavefront Sensor, Emma Branigan, Andreas Zepp, Suzanne Martin, Matthew Sheehan, Szymon Gladysz, Kevin Murphy

Conference Papers

A new holographic recording setup has been developed for the fabrication of single- and multi-mode photopolymer-based analog holographic wavefront sensors. A second setup has been built and used to characterise the sensor at several wavelengths.

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