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8,858 full-text articles. Page 42 of 309.

Astr 117, 2023 University of Nebraska - Lincoln

Astr 117

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 151, 2023 University of Nebraska - Lincoln

Phys 151

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 452/852, 2023 University of Nebraska - Lincoln

Phys 452/852

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 462/862, 2023 University of Nebraska - Lincoln

Phys 462/862

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 912, 2023 University of Nebraska - Lincoln

Phys 912

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 913, 2023 University of Nebraska - Lincoln

Phys 913

Department of Physics and Astronomy: Syllabi

No abstract provided.


Phys 917, 2023 University of Nebraska - Lincoln

Phys 917

Department of Physics and Astronomy: Syllabi

No abstract provided.


Conformational Landscapes Of Symmetrically Fluorine-Substituted Benzoic Acids I: Microwave Spectroscopic And Theoretical Studies On 3,5-Difluorobenzoic Acid, Alitza Gracia, Jingling Hong, Rebakah Arismendi, Mingfei Zhou, Weixing Li, Wei Lin 2023 The University of Texas Rio Grande Valley

Conformational Landscapes Of Symmetrically Fluorine-Substituted Benzoic Acids I: Microwave Spectroscopic And Theoretical Studies On 3,5-Difluorobenzoic Acid, Alitza Gracia, Jingling Hong, Rebakah Arismendi, Mingfei Zhou, Weixing Li, Wei Lin

Physics & Astronomy Faculty Publications

We report our combined theoretical and spectroscopic studies on 3,5-difluorobenzoic acid. Using a chirped pulse Fourier transform microwave (CP-FTMW) spectrometer, we recorded and analyzed the rotational spectrum spanning the frequency range of 6 – 12.5 GHz. Quantum chemical calculations were employed to analyze the conformational changes and landscapes of 3,5-difluorobenzoic acid. These calculations focused on studying the potential energy surfaces along the CCCO and OCOH dihedral angles at the B3LYP/6-311G level. Based on the computational results, we identified the global minimum conformer 1 as well as the local minimum conformer 2. We discussed and interpreted the geometric structures of the …


A Review On Antibacterial Activity Of Nanoparticles, Badr-Edine Sadoq, Mohammed Reda Britel, Adel Bouajaj, Ramzi Maâlej, Ahmed Touhami, Marwa Abid, Hanen Douiri, Fakhita Touhami, Amal Maurady 2023 The University of Texas Rio Grande Valley

A Review On Antibacterial Activity Of Nanoparticles, Badr-Edine Sadoq, Mohammed Reda Britel, Adel Bouajaj, Ramzi Maâlej, Ahmed Touhami, Marwa Abid, Hanen Douiri, Fakhita Touhami, Amal Maurady

Physics & Astronomy Faculty Publications

The increasing resistance of bacteria to antibiotic agents is a main global public health problem. The use of nanoparticles is one of the promising ways to overcome microbial resistance to antimicrobial agents. Metal nanoparticles are increasingly used to target bacterial strains. Advances in nanotechnology, in particular the ability to synthesize nanoparticles of specific size and shape, are likely to lead to the development of new antibacterial agents. The antibacterial activities of nanoparticles are largely influenced by their sizes and large surface area/mass ratio. The antibacterial mechanisms of nanoparticles are poorly understood, but the currently accepted mechanisms include oxidative stress induction, …


Search For Subsolar-Mass Black Hole Binaries In The Second Part Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang 2023 The University of Texas Rio Grande Valley

Search For Subsolar-Mass Black Hole Binaries In The Second Part Of Advanced Ligo’S And Advanced Virgo’S Third Observing Run, R. Abbott, H. Abe, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We describe a search for gravitational waves from compact binaries with at least one component with mass 0.2 –1.0M⊙ and mass ratio q ≥ 0.1 in Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) and Advanced Virgo data collected between 2019 November 1, 15:00 UTC and 2020 March 27, 17:00 UTC. No signals were detected. The most significant candidate has a false alarm rate of 0.2yr−1 ⁠. We estimate the sensitivity of our search over the entirety of Advanced LIGO’s and Advanced Virgo’s third observing run, and present the most stringent limits to date on the merger rate of binary black holes …


Rubin Observatory Lsst Transients And Variable Stars Roadmap, Kelly M. Hambleton, Federica B. Bianco, Rachel Street, Keaton Bell, David Buckley, Melissa Graham, Nina Hernitschek, Michael B. Lund, Elena Mason, Liliana Rivera Sandoval 2023 The University of Texas Rio Grande Valley

Rubin Observatory Lsst Transients And Variable Stars Roadmap, Kelly M. Hambleton, Federica B. Bianco, Rachel Street, Keaton Bell, David Buckley, Melissa Graham, Nina Hernitschek, Michael B. Lund, Elena Mason, Liliana Rivera Sandoval

Physics & Astronomy Faculty Publications

The Vera C. Rubin Legacy Survey of Space and Time (LSST) holds the potential to revolutionize time domain astrophysics, reaching completely unexplored areas of the Universe and mapping variability time scales from minutes to a decade. To prepare to maximize the potential of the Rubin LSST data for the exploration of the transient and variable Universe, one of the four pillars of Rubin LSST science, the Transient and Variable Stars Science Collaboration, one of the eight Rubin LSST Science Collaborations, has identified research areas of interest and requirements, and paths to enable them. While our roadmap is ever-evolving, this document …


Conformational Landscapes Of Symmetrically Fluorine-Substituted Benzoic Acids Ii: Calculations And Measurements For The Rotational Spectrum And Structure Of 3,4,5-Trifluorobenzoic Acid, Jingling Hong, Alitza Gracia, Savannah Romero, Mingfei Zhou, Wei Lin, Weixing Li 2023 The University of Texas Rio Grande Valley

Conformational Landscapes Of Symmetrically Fluorine-Substituted Benzoic Acids Ii: Calculations And Measurements For The Rotational Spectrum And Structure Of 3,4,5-Trifluorobenzoic Acid, Jingling Hong, Alitza Gracia, Savannah Romero, Mingfei Zhou, Wei Lin, Weixing Li

Physics & Astronomy Faculty Publications

Calculations on the structure of 3,4,5-trifluorobenzoic acid were made using the Gaussian 16 program. The potential energy surfaces were scanned along CCCO and OCOH dihedral angles at the B3LYP/6-311G level to analyze its conformational landscape. Two conformations were identified and reoptimized at the B3LYP/aug-cc-pVTZ level. The result indicates that 3,4,5-trifluorobenzoic acid prefers a planar structure in its global minimum conformation. The pure rotational spectra of 3,4,5-trifluorobenzoic acid were measured in the frequency range of 6 – 12.5 GHz using a chirped pulse Fourier transform microwave (CP-FTMW) spectrometer. The spectra of the parent, seven 13C, and one deuterium singly substituted isotopologues …


Search For Gravitational Waves Associated With Fast Radio Bursts Detected By Chime/Frb During The Ligo–Virgo Observing Run O3a, R. Abbott, T. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang 2023 The University of Texas Rio Grande Valley

Search For Gravitational Waves Associated With Fast Radio Bursts Detected By Chime/Frb During The Ligo–Virgo Observing Run O3a, R. Abbott, T. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We search for gravitational-wave (GW) transients associated with fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project, during the first part of the third observing run of Advanced LIGO and Advanced Virgo (2019 April 1 15:00 UTC–2019 October 1 15:00 UTC). Triggers from 22 FRBs were analyzed with a search that targets both binary neutron star (BNS) and neutron star–black hole (NSBH) mergers. A targeted search for generic GW transients was conducted on 40 FRBs. We find no significant evidence for a GW association in either search. Given the large uncertainties in the …


Effects Of Spin-Orbit Coupling On Gravitational Waveforms From A Triaxial Nonaligned Neutron Star In A Binary System, Wen-Fan Feng, Tan Liu, Jie-Wen Che, Yan Wang, Soumya D. Mohanty 2023 The University of Texas Rio Grande Valley

Effects Of Spin-Orbit Coupling On Gravitational Waveforms From A Triaxial Nonaligned Neutron Star In A Binary System, Wen-Fan Feng, Tan Liu, Jie-Wen Che, Yan Wang, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

Spinning neutron stars (NSs) can emit continuous gravitational waves (GWs) that carry a wealth of information about the compact object. If such a signal is detected, it will provide us with new insight into the physical properties of matter under extreme conditions. According to binary population synthesis simulations, future space-based GW detectors, such as LISA and TianQin, can potentially detect some double NSs in tight binaries with orbital periods shorter than 10 minutes. The possibility of a successful directed search for continuous GWs from the spinning NS in such a binary system identified by LISA/TianQin will be significantly increased with …


Organizing Pmode Dopplergrams Of Jupiter With Matlab, Brady T. Smith, Deborah Gulledge, Cody Shaw, Gerard Williger 2023 University of Louisville

Organizing Pmode Dopplergrams Of Jupiter With Matlab, Brady T. Smith, Deborah Gulledge, Cody Shaw, Gerard Williger

The Cardinal Edge

The interiors of the giant planets are poorly known. At the time of writing, such investigations have been limited to measuring gravitational effects from a handful of orbital probes. The most recent attempt to map the interior is via PMODE (the Planetary Multilevel Oscillations and Dynamics Experiment), designed to explore Jupiter’s core by collecting Dopplergrams. Small radial velocity shifts in Jupiter’s upper cloud decks enable us to map its atmospheric dynamics and consequently its interior via Dioseismology (techniques similar to Helioseismology, applied to Jupiter). This campaign produced a vast dataset with more than 50,000 exposures, every 30 seconds, over 24 …


Anharmonic Ir Absorption Spectra Of The Prototypical Interstellar Pahs Phenanthrene, Pyrene, And Pentacene In Their Neutral And Cation States, Vincent J. Esposito, Louis J. Allamandola, Christiaan Boersma, Jesse D. Bregman, Ryan C. Fortenberry, Alexandros Maragkoudakis, Pasquale Temi 2023 Chapman University

Anharmonic Ir Absorption Spectra Of The Prototypical Interstellar Pahs Phenanthrene, Pyrene, And Pentacene In Their Neutral And Cation States, Vincent J. Esposito, Louis J. Allamandola, Christiaan Boersma, Jesse D. Bregman, Ryan C. Fortenberry, Alexandros Maragkoudakis, Pasquale Temi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Combination band and overtone transitions of polycyclic aromatic hydrocarbon (PAH) cations in the 2000–2900 cm-1 (5-3.5 µm) region are implicated as carriers of the ‘quasi-continuum’ observed in the near-infrared (IR) emission spectra of many astronomical objects. In neutral PAHs, the strongest absorption features are concentrated in the 700–900 cm-1 (14–11 µm) range, which are associated with CH out-of-plane bending motions. Upon ionization, this shifts to the 1000–1600 cm-1 (10–6 µm) range, where bands are associated with C=C stretches and CH in-plane bends. Anharmonicity is required to accurately characterize the IR absorption spectrum of PAHs, indicated herein by …


The Rs Oph Outburst Of 2021 Monitored In X-Rays With Nicer, Marina Orio, Keith Gendreau, Morgan Giese, Gerardo Jaun M. Luna, Jozef Magdolen, Tod E. Strohmayer, Andy E. Zhang, Diego Altamirano, Andrej Dobrotka, Teruaki Enoto, Elizabeth C. Ferrara, Richard Ignace, Sebastian Heinz, Craig Markwardt, Joy S. Nichols, Michael L. Parker, Dheeraj R. Pasham, Songpeng Pei, Pragati Pradhan, Ron Remillard, James F. Steiner, Francesco Tombesi 2023 Embry-Riddle Aeronautical University

The Rs Oph Outburst Of 2021 Monitored In X-Rays With Nicer, Marina Orio, Keith Gendreau, Morgan Giese, Gerardo Jaun M. Luna, Jozef Magdolen, Tod E. Strohmayer, Andy E. Zhang, Diego Altamirano, Andrej Dobrotka, Teruaki Enoto, Elizabeth C. Ferrara, Richard Ignace, Sebastian Heinz, Craig Markwardt, Joy S. Nichols, Michael L. Parker, Dheeraj R. Pasham, Songpeng Pei, Pragati Pradhan, Ron Remillard, James F. Steiner, Francesco Tombesi

Publications

The 2021 outburst of the symbiotic recurrent nova RS Oph was monitored with the Neutron Star Interior Composition Explorer Mission (NICER) in the 0.2–12 keV range from day one after the optical maximum, until day 88, producing an unprecedented, detailed view of the outburst development. The X-ray flux preceding the supersoft X-ray phase peaked almost 5 days after optical maximum and originated only in shocked ejecta for 21–25 days. The emission was thermal; in the first 5 days, only a non-collisional-ionization equilibrium model fits the spectrum, and a transition to equilibrium occurred between days 6 and 12. The ratio of …


Observation Of Self-Patterned Defect Formation In Atomic Superfluids–From Ring Dark Solitons To Vortex Dipole Necklaces, Hikaru Tamura, Cheng-An Chen, Chen-Lung Hung 2023 Purdue University

Observation Of Self-Patterned Defect Formation In Atomic Superfluids–From Ring Dark Solitons To Vortex Dipole Necklaces, Hikaru Tamura, Cheng-An Chen, Chen-Lung Hung

Purdue University Libraries Open Access Publishing Fund

Unveiling nonequilibrium dynamics of solitonic and topological defect structures in a multidimensional nonlinear medium is a current frontier across diverse fields. One of the quintessential objects is a ring dark soliton (RDS), whose dynamics are expected to display remarkable interplay between symmetry and self-patterned topological defect formation from a transverse (snake) instability, but it has thus far evaded full experimental observations. Here, we report an experimental realization of RDS generation in a two-dimensional atomic superfluid trapped in a circular box. By quenching the confining box potential, we observe an RDS emitted from the edge and its peculiar signature in the …


Survey Of X-Rays From Massive Stars Observed At High Spectral Resolution With Chandra, Pragati Pradhan, David P. Huenemoerder, Richard Ignace, Joy S. Nichols, A.M.T. Pollock 2023 Embry-Riddle Aeronautical University

Survey Of X-Rays From Massive Stars Observed At High Spectral Resolution With Chandra, Pragati Pradhan, David P. Huenemoerder, Richard Ignace, Joy S. Nichols, A.M.T. Pollock

Publications

Identifying trends between observational data and the range of physical parameters of massive stars is a critical step to the still-elusive full understanding of the source, structure, and evolution of X-ray emission from the stellar winds, requiring a substantial sample size and systematic analysis methods. As of 2022, the Chandra data archive contains 37 high-resolution spectra of O, B, and WR stars, observed with the Chandra/HETGS, and of sufficient quality to fit the continua and emission-line profiles. Using a systematic approach to the data analysis, we explore morphological trends in the line profiles (i.e., O, Ne, Mg, and Si) and …


Exploring The Capabilities Of Gibbs Sampling In Pulsar Timing Arrays, Nima Laal, William G. Lamb, Joseph D. Romano, Xavier Siemens, Stephen R. Taylor, Rutger van Haasteren 2023 The University of Texas Rio Grande Valley

Exploring The Capabilities Of Gibbs Sampling In Pulsar Timing Arrays, Nima Laal, William G. Lamb, Joseph D. Romano, Xavier Siemens, Stephen R. Taylor, Rutger Van Haasteren

Physics & Astronomy Faculty Publications

We explore the use of Gibbs sampling in estimating the noise properties of individual pulsars and illustrate its effectiveness using the NANOGrav 11-year dataset. We find that Gibbs sampling noise modeling (GM) is more efficient than the current standard Bayesian techniques (SM) for single pulsar analyses by yielding model parameter posteriors with average effective-sample-size ratio (GM/SM) of 6 across all parameters and pulsars. Furthermore, the output of GM contains posteriors for the Fourier coefficients that can be used to characterize the underlying red noise process of any pulsar’s timing residuals, which are absent in current implementations of SM. Through simulations, …


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