Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Missouri University of Science and Technology

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 811 - 840 of 6056

Full-Text Articles in Physical Sciences and Mathematics

Robust Control Of The Minima Of High-Order Harmonics By Fine-Tuning The Alignment Of Co₂ Molecules For Shaping Attosecond Pulses And Probing Molecular Alignment, Cheng Jin, Su Ju Wang, Song Feng Zhao, Anh-Thu Le, C. D. Lin Jul 2020

Robust Control Of The Minima Of High-Order Harmonics By Fine-Tuning The Alignment Of Co₂ Molecules For Shaping Attosecond Pulses And Probing Molecular Alignment, Cheng Jin, Su Ju Wang, Song Feng Zhao, Anh-Thu Le, C. D. Lin

Physics Faculty Research & Creative Works

In a recent paper [C. Jin, S.-J. Wang, X. Zhao, S.-F. Zhao, and C. D. Lin, Phys. Rev. A 101, 013429 (2020)2469-992610.1103/PhysRevA.101.013429], we reported that the position and depth of the minima in the harmonic spectra of CO2 molecules can be dramatically manipulated by a slight change of the degree of alignment, thus providing a convenient method of shaping attosecond pulses which could lead to the splitting of a typical single attosecond burst into two. Here, we demonstrate that harmonic minima can also be dramatically controlled by changing the pump-probe angles to shape attosecond pulses. In the meanwhile, since …

Go to article

On The Noisy Gradient Descent That Generalizes As Sgd, Jingfeng Wu, Wenqing Hu, Haoyi Xiong, Jun Huan, Vladimir Braverman, Zhanxing Zhu Jul 2020

On The Noisy Gradient Descent That Generalizes As Sgd, Jingfeng Wu, Wenqing Hu, Haoyi Xiong, Jun Huan, Vladimir Braverman, Zhanxing Zhu

Mathematics and Statistics Faculty Research & Creative Works

The gradient noise of SGD is considered to play a central role in the observed strong generalization abilities of deep learning. While past studies confirm that the magnitude and covariance structure of gradient noise are critical for regularization, it remains unclear whether or not the class of noise distributions is important. In this work we provide negative results by showing that noises in classes different from the SGD noise can also effectively regularize gradient descent. Our finding is based on a novel observation on the structure of the SGD noise: it is the multiplication of the gradient matrix and a …

Go to article

Role Of Fluid Injection On Earthquake Size In Dynamic Rupture Simulations On Rough Faults, Jeremy Maurer, Eric M. Dunham, Paul Segall Jul 2020

Role Of Fluid Injection On Earthquake Size In Dynamic Rupture Simulations On Rough Faults, Jeremy Maurer, Eric M. Dunham, Paul Segall

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

An outstanding question for induced seismicity is whether the volume of injected fluid and/or the spatial extent of the resulting pore pressure and stress perturbations limit rupture size. We simulate ruptures with and without injection‐induced pore pressure perturbations, using 2‐D dynamic rupture simulations on rough faults. Ruptures are not necessarily limited by pressure perturbations when (1) background shear stress is above a critical value, or (2) pore pressure is high. Both conditions depend on fault roughness. Stress heterogeneity from fault roughness primarily determines where ruptures stop; pore pressure has a secondary effect. Ruptures may be limited by fluid volume or …

Go to article

Collective Modes At A Disordered Quantum Phase Transition, Martin Puschmann, Jack Crewse, Jose A. Hoyos, Thomas Vojta Jul 2020

Collective Modes At A Disordered Quantum Phase Transition, Martin Puschmann, Jack Crewse, Jose A. Hoyos, Thomas Vojta

Physics Faculty Research & Creative Works

We study the collective excitations, i.e., the Goldstone (phase) mode and the Higgs (amplitude) mode, near the superfluid-Mott glass quantum phase transition in a two-dimensional system of disordered bosons. Using Monte Carlo simulations as well as an inhomogeneous quantum mean-field theory with Gaussian fluctuations, we show that the Higgs mode is strongly localized for all energies, leading to a noncritical scalar response. In contrast, the lowest-energy Goldstone mode undergoes a striking delocalization transition as the system enters the superfluid phase. We discuss the generality of these findings and experimental consequences, and we point out potential relations to many-body localization.

Go to article

Observation Of The Low-Frequency Spectrum Of The Water Trimer As A Sensitive Test Of The Water-Trimer Potential And The Dipole-Moment Surface, Raffael Schwan, Chen Qu, Devendra Mani, Nitish Pal, Gerhard Schwaab, Joel M. Bowman, Gregory S. Tschumper, Martina Havenith Jul 2020

Observation Of The Low-Frequency Spectrum Of The Water Trimer As A Sensitive Test Of The Water-Trimer Potential And The Dipole-Moment Surface, Raffael Schwan, Chen Qu, Devendra Mani, Nitish Pal, Gerhard Schwaab, Joel M. Bowman, Gregory S. Tschumper, Martina Havenith

Chemistry Faculty Research & Creative Works

Intermolecular interactions in bulk water are dominated by pairwise and non-pairwise cooperative interactions. While accurate descriptions of the pairwise interactions are available and can be tested by precise low-frequency spectra of the water dimer up to 550 cm−1, the same does not hold for the three-body interactions. Here, we report the first comprehensive spectrum of the water trimer in the frequency region from 70 to 620 cm−1 using helium-nanodroplet isolation and free-electron lasers. By comparison to accompanying high-level quantum calculations, the experimentally observed intermolecular bands can be assigned. The transition frequencies of the degenerate translation, the degenerate in-plane and the …

Go to article

Stationary And Dynamical Properties Of Two Harmonically Trapped Bosons In The Crossover From Two Dimensions To One, G. Bougas, Simeon I. Mistakidis, G. M. Alshalan, P. Schmelcher Jul 2020

Stationary And Dynamical Properties Of Two Harmonically Trapped Bosons In The Crossover From Two Dimensions To One, G. Bougas, Simeon I. Mistakidis, G. M. Alshalan, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Stationary Properties And The Interaction Quench Dynamics Of Two Bosons, Confined In A Two-Dimensional Anisotropic Harmonic Trap. A Transcendental Equation Is Derived Giving Access To The Energy Spectrum And Revealing The Dependence Of The Energy Gaps On The Anisotropy Parameter. The Relation Between The Two- And One-Dimensional Scattering Lengths As Well As The Tan Contacts Is Established. The Contact, Capturing The Two-Body Short-Range Correlations, Shows An Increasing Tendency For A Larger Anisotropy. Subsequently, The Interaction Quench Dynamics From Attractive To Repulsive Values And Vice Versa Is Investigated For Various Anisotropies. A Closed Analytical Form Of The Expansion …

Go to article

Many-Body Effects On Second-Order Phase Transitions In Spinor Bose-Einstein Condensates And Breathing Dynamics, K. M. Mittal, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher Jul 2020

Many-Body Effects On Second-Order Phase Transitions In Spinor Bose-Einstein Condensates And Breathing Dynamics, K. M. Mittal, Simeon I. Mistakidis, P. G. Kevrekidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Unravel The Correlation Effects Of The Second-Order Quantum Phase Transitions Emerging On The Ground State Of A Harmonically Trapped Spin-1 Bose Gas, Upon Varying The Involved Zeeman Terms, As Well As Its Breathing Dynamics Triggered By Quenching The Trapping Frequency. It Is Found That The Boundaries Of The Associated Magnetic Phases Are Altered In The Presence Of Interparticle Correlations For Both Ferromagnetic And Antiferromagnetic Spin-Spin Interactions, An Effect Which Becomes More Prominent In The Few-Body Scenario. Most Importantly, We Unveil A Correlation-Induced Shrinking Of The Antiferromagnetic And Broken-Axisymmetry Phases Implying That Ground States With Bosons Polarized In A Single …

Go to article

Groundwater Storage Loss Associated With Land Subsidence In Western United States Mapped Using Machine Learning, Ryan G. Smith, Sayantan Majumdar Jul 2020

Groundwater Storage Loss Associated With Land Subsidence In Western United States Mapped Using Machine Learning, Ryan G. Smith, Sayantan Majumdar

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Land subsidence caused by groundwater extraction has numerous negative consequences, such as loss of groundwater storage and damage to infrastructure. Understanding the magnitude, timing, and locations of land subsidence, as well as the mechanisms driving it, is crucial to implementing mitigation strategies, yet the complex, nonlinear processes causing subsidence are difficult to quantify. Physical models relating groundwater flux to aquifer compaction exist but require substantial hydrological data sets and are time consuming to calibrate. Land deformation can be measured using interferometric synthetic aperture radar (InSAR) and GPS, but the former is computationally expensive to estimate at scale and is subject …

Go to article

A Bayesian Framework To Unravel Food, Groundwater, And Climate Linkages: A Case Study From Louisiana, Nitin K. Singh, Ruchi Bhattacharya, David M. Borrok Jul 2020

A Bayesian Framework To Unravel Food, Groundwater, And Climate Linkages: A Case Study From Louisiana, Nitin K. Singh, Ruchi Bhattacharya, David M. Borrok

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Advancing our understanding of the connections among groundwater, food, and climate is critical to meet global food demands while optimizing water resources usage. However, our understanding of the linkages among groundwater, food, and climate is still limited. Here, we offer a Bayesian framework to simulate crop yield at a regional scale and quantify its relationships and associated uncertainty with climate, groundwater, agricultural, and energy-related variables. We implemented the framework in the rice-producing regions of Louisiana from 1960-2015. To build a parsimonious model, we used a probability-based variable selection approach to detect the key drivers of rice yield. Rice yield increased, …

Go to article

Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta Jun 2020

Serotonergic Axons As Fractional Brownian Motion Paths: Insights Into The Self-Organization Of Regional Densities, Skirmantas Janusonis, Nils Detering, Ralf Metzler, Thomas Vojta

Physics Faculty Research & Creative Works

All vertebrate brains contain a dense matrix of thin fibers that release serotonin (5-hydroxytryptamine), a neurotransmitter that modulates a wide range of neural, glial, and vascular processes. Perturbations in the density of this matrix have been associated with a number of mental disorders, including autism and depression, but its self-organization and plasticity remain poorly understood. We introduce a model based on reflected Fractional Brownian Motion (FBM), a rigorously defined stochastic process, and show that it recapitulates some key features of regional serotonergic fiber densities. Specifically, we use supercomputing simulations to model fibers as FBM-paths in two-dimensional brain-like domains and demonstrate …

Go to article

Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website. Jun 2020

Z₃-Vestigial Nematic Order Due To Superconducting Fluctuations In The Doped Topological Insulators Nbₓbi₂Se₃ And Cuₓbi₂Se₃, Chang Woo Cho, Junying Shen, Jian Lyu, Omargeldi Atanov, Qianxue Chen, Seng Huat Lee, Yew San Hor, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

A state of matter with a multi-component order parameter can give rise to vestigial order. In the vestigial phase, the primary order is only partially melted, leaving a remaining symmetry breaking behind, an effect driven by strong classical or quantum fluctuations. Vestigial states due to primary spin and charge-density-wave order have been discussed in iron-based and cuprate materials. Here we present the observation of a partially melted superconductivity in which pairing fluctuations condense at a separate phase transition and form a nematic state with broken Z3, i.e., three-state Potts-model symmetry. Thermal expansion, specific heat and magnetization measurements of …

Go to article

Vanishing Porosity Limit Of The Coupled Stokes-Brinkman System, Mingwen Fei, Dongjuan Niu, Xiaoming Wang Jun 2020

Vanishing Porosity Limit Of The Coupled Stokes-Brinkman System, Mingwen Fei, Dongjuan Niu, Xiaoming Wang

Mathematics and Statistics Faculty Research & Creative Works

We investigate the small porosity asymptotic behavior of the coupled Stokes-Brinkman system in the presence of a curved interface between the Stokes region and the Brinkman region. in particular, we derive a set of approximate solutions, validated via rigorous analysis, to the coupled Stokes-Brinkman system. of particular interest is that the approximate solution satisfies a generalized Beavers-Joseph-Saffman-Jones interface condition (1.9) with the constant of proportionality independent of the curvature of the interface.

Go to article

Motifs Enable Communication Efficiency And Fault-Tolerance In Transcriptional Networks, Satyaki Roy, Preetam Ghosh, Dipak Barua, Sajal K. Das Jun 2020

Motifs Enable Communication Efficiency And Fault-Tolerance In Transcriptional Networks, Satyaki Roy, Preetam Ghosh, Dipak Barua, Sajal K. Das

Computer Science Faculty Research & Creative Works

Analysis of the topology of transcriptional regulatory networks (TRNs) is an effective way to study the regulatory interactions between the transcription factors (TFs) and the target genes. TRNs are characterized by the abundance of motifs such as feed forward loops (FFLs), which contribute to their structural and functional properties. In this paper, we focus on the role of motifs (specifically, FFLs) in signal propagation in TRNs and the organization of the TRN topology with FFLs as building blocks. To this end, we classify nodes participating in FFLs (termed motif central nodes) into three distinct roles (namely, roles A, B …

Go to article

Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin Jun 2020

Two-Loop Corrections To The Large-Order Behavior Of Correlation Functions In The One-Dimensional N-Vector Model, L. T. Giorgini, Ulrich D. Jentschura, E. M. Malatesta, G. Parisi, T. Rizzo, J. Zinn-Justin

Physics Faculty Research & Creative Works

For a long time, the predictive limits of perturbative quantum field theory have been limited by our inability to carry out loop calculations to an arbitrarily high order, which become increasingly complex as the order of perturbation theory is increased. This problem is exacerbated by the fact that perturbation series derived from loop diagram (Feynman diagram) calculations represent asymptotic (divergent) series which limits the predictive power of perturbative quantum field theory. Here, we discuss an ansatz that could overcome these limits, based on the observations that (i) for many phenomenologically relevant field theories, one can derive dispersion relations which relate …

Go to article

Handling Missing Data For Unsupervised Learning With An Application On A Fitbir Traumatic Brain Injury (Tbi) Dataset, Louis Steinmeister, Dacosta Yeboah, Gayla Olbricht, Tayo Obafemi-Ajayi, Bassam Hadi, Daniel Hier, Donald C. Wunsch Jun 2020

Handling Missing Data For Unsupervised Learning With An Application On A Fitbir Traumatic Brain Injury (Tbi) Dataset, Louis Steinmeister, Dacosta Yeboah, Gayla Olbricht, Tayo Obafemi-Ajayi, Bassam Hadi, Daniel Hier, Donald C. Wunsch

Mathematics and Statistics Faculty Research & Creative Works

"The problem of missing data and imputation have been widely discussed amongst specialists. However, many data scientists and applied statisticians fail to appropriately consider this issue. Often, it seems intuitive to discard observations containing missing data or simply to substitute means. This can lead to disastrous consequences, particularly in an era of exponentially increasing data volumes. In the following, we show how inappropriate handling of missing data and an insufficient analysis of the censoring mechanism can lead to a bias, overconfidence in the estimation of parameters, could challenge the reproducibility of obtained results, and may distort the structure of the …

Go to article

Anchoring The Hydrogen Sulfide Dimer Potential Energy Surface To Juxtapose (H2s)2 With (H2o)2, Morgan A. Perkins, Kayleigh R. Barlow, Katelyn M. Dreux, Gregory S. Tschumper Jun 2020

Anchoring The Hydrogen Sulfide Dimer Potential Energy Surface To Juxtapose (H2s)2 With (H2o)2, Morgan A. Perkins, Kayleigh R. Barlow, Katelyn M. Dreux, Gregory S. Tschumper

Chemistry Faculty Research & Creative Works

Twelve stationary points have been characterized on the (H2S)2 potential energy surface using the MP2 and CCSD(T) methods with large, correlation consistent basis sets. To the best of our knowledge, five of the structures have not been identified elsewhere and are presented here for the first time. A similar analysis was performed on the ten, well-known structures of the water dimer in order to facilitate direct comparisons between the corresponding (H2O)2 and (H2S)2 configurations. Harmonic vibrational frequency computations identify three (H2S)2 configurations as minima, four as transition states, …

Go to article

A Minimal Congruence Lattice Representation For 𝕄ₚ₊₁, Roger Bunn, David E. Grow, Matt Insall, Philip Thiem Jun 2020

A Minimal Congruence Lattice Representation For 𝕄ₚ₊₁, Roger Bunn, David E. Grow, Matt Insall, Philip Thiem

Mathematics and Statistics Faculty Research & Creative Works

Let p be an odd prime. The unary algebra consisting of the dihedral group of order 2p, acting on itself by left translation, is a minimal congruence lattice representation of 𝕄p+1.

Go to article

Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura Jun 2020

Fifth Force And Hyperfine Splitting In Bound Systems, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

Two recent experimental observations at the ATOMKI Institute of the Hungarian Academy of Sciences (regarding the angular emission pattern of electron-positron pairs from nuclear transitions from excited states in 8Be and 4He) indicate the possible existence of a particle of a rest mass energy of roughly 17 MeV. The so-called X17 particle constitutes a virtual state in the process, preceding the emission of the electron-positron pair. Based on the symmetry of the nuclear transitions (1+ → 0+ and 0- →0 +), the X17 could either be a vector, or a pseudoscalar particle. Here, we …

Go to article

Proof-Of-Activity Consensus Protocol Based On A Network's Active Nodes, Roman Belfer, Antonina Kashtalian, Andrii Nicheporuk, George Markowsky, Anatoliy Sachenko Jun 2020

Proof-Of-Activity Consensus Protocol Based On A Network's Active Nodes, Roman Belfer, Antonina Kashtalian, Andrii Nicheporuk, George Markowsky, Anatoliy Sachenko

Computer Science Faculty Research & Creative Works

The paper proposes a new socially oriented protocol that avoids pseudo-decentralization and monopolization of the network, increases the availability of the system, provides a fair selection of potential validator nodes, and provides a fair reward for creating new blocks and adding them to the blockchain. Our proposed protocol provides for the creation and addition of new blocks to a blockchain. Defines a node validator, which will create the next block according to its useful activity in the network according to predefined conditions, which can be formed according to the requirements of the system and will satisfy the individual needs of …

Go to article

Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher Jun 2020

Interplay Of Phase Separation And Itinerant Magnetism For Correlated Few Fermions In A Double-Well, G. M. Koutentakis, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Explore The Stability Of The Phase Separation Phenomenon In Few-Fermion Spin-1/2 Systems Confined In A Double-Well Potential. It Is Shown That Within The SU(2) Symmetric Case, Where The Total Spin Is Conserved, The Phase Separation Cannot Be Fully Stabilized. An Interaction Regime Characterized By Metastable Phase Separation Emerges For Intermediate Interactions Which Is Inherently Related With Ferromagnetic Spin-Spin Correlations Emerging Within Each Of The Wells. The Breaking Of The SU(2) Symmetry Crucially Affects The Stability Properties Of The System As The Phase Separated State Can Be Stabilized Even For Weak Magnetic Potential Gradients. Our Results Imply An Intricate Relation …

Go to article

Induced Correlations Between Impurities In A One-Dimensional Quenched Bose Gas, Simeon I. Mistakidis, A. G. Volosniev, P. Schmelcher May 2020

Induced Correlations Between Impurities In A One-Dimensional Quenched Bose Gas, Simeon I. Mistakidis, A. G. Volosniev, P. Schmelcher

Physics Faculty Research & Creative Works

We Explore The Time Evolution Of Two Impurities In A Trapped One-Dimensional Bose Gas That Follows A Change Of The Boson-Impurity Interaction. We Study The Induced Impurity-Impurity Interactions And Their Effect On The Quench Dynamics. In Particular, We Report On The Size Of The Impurity Cloud, The Impurity-Impurity Entanglement, And The Impurity-Impurity Correlation Function. The Presented Numerical Simulations Are Based Upon The Variational Multilayer Multiconfiguration Time-Dependent Hartree Method For Bosons. To Analyze And Quantify Induced Impurity-Impurity Correlations, We Employ An Effective Two-Body Hamiltonian With A Contact Interaction. We Show That The Effective Model Consistent With The Mean-Field Attraction Of Two …

Go to article

Origin Of High Carrier Concentration In Amorphous Wide-Bandgap Oxides: Role Of Disorder In Defect Formation And Electron Localization In In₂O₃₋​ₓ, Julia E. Medvedeva, I. A. Zhuravlev, C. Burris, D. B. Buchholz, M. Grayson, R. P. H. Chang May 2020

Origin Of High Carrier Concentration In Amorphous Wide-Bandgap Oxides: Role Of Disorder In Defect Formation And Electron Localization In In₂O₃₋​ₓ, Julia E. Medvedeva, I. A. Zhuravlev, C. Burris, D. B. Buchholz, M. Grayson, R. P. H. Chang

Physics Faculty Research & Creative Works

Structural disorder has been known to suppress carrier concentration and carrier mobility in common covalent semiconductors, such as silicon, by orders of magnitude. This is expected from a reduced overlap of the electron clouds on neighboring orbitals and the formation of localized tail states near the band edges caused by local distortions and lack of periodicity in the amorphous phase. In striking contrast to the covalent semiconductors, wide-bandgap oxides of post-transition metals with ionic bonding not only allow for crystalline-like electron mobility upon amorphization, but also exhibit two orders of magnitude higher carrier concentration in the disordered phase as compared …

Go to article

Correlated Dynamics Of Fermionic Impurities Induced By The Counterflow Of An Ensemble Of Fermions, J. Kwasniok, Simeon I. Mistakidis, P. Schmelcher May 2020

Correlated Dynamics Of Fermionic Impurities Induced By The Counterflow Of An Ensemble Of Fermions, J. Kwasniok, Simeon I. Mistakidis, P. Schmelcher

Physics Faculty Research & Creative Works

We Investigate The Nonequilibrium Quantum Dynamics Of One And Two Heavy Fermionic Impurities Being Harmonically Trapped And Repulsively Interacting With A Finite Ensemble Of Majority Fermions. A Quench Of The Potential Of The Majority Species From A Double-Well To A Harmonic Trap Is Applied, Enforcing Its Counterflow, Which In Turn Perturbs The Impurities. For Weak Repulsions, It Is Shown That The Mixture Undergoes A Periodic Mixing And Demixing Dynamics, While Stronger Interactions Lead To A More Pronounced Dynamical Spatial Separation. In The Presence Of Correlations, The Impurity Exhibits An Expansion Dynamics Which Is Absent In The Hartree-Fock Case, Resulting In …

Go to article

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, Download The Pdf. Apr 2020

Optically Targeted Search For Gravitational Waves Emitted By Core-Collapse Supernovae During The First And Second Observing Runs Of Advanced Ligo And Advanced Virgo, B. P. Abbott, R. Abbott, Marco Cavaglia, For Full List Of Authors, Download The Pdf.

Physics Faculty Research & Creative Works

We present the results from a search for gravitational-wave transients associated with core-collapse supernovae observed within a source distance of approximately 20 Mpc during the first and second observing runs of Advanced LIGO and Advanced Virgo. No significant gravitational-wave candidate was detected. We report the detection efficiencies as a function of the distance for waveforms derived from multidimensional numerical simulations and phenomenological extreme emission models. The sources with neutrino-driven explosions are detectable at the distances approaching 5 kpc, and for magnetorotationally driven explosions the distances are up to 54 kpc. However, waveforms for extreme emission models are detectable up to …

Go to article

Parameter Identification For Gompertz And Logistic Dynamic Equations, Elvan Akin, Neslihan Nesliye Pelen, Ismail Ugur Tiryaki, Fusun Yalcin Apr 2020

Parameter Identification For Gompertz And Logistic Dynamic Equations, Elvan Akin, Neslihan Nesliye Pelen, Ismail Ugur Tiryaki, Fusun Yalcin

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we generalize and compare Gompertz and Logistic dynamic equations in order to describe the growth patterns of bacteria and tumor. First of all, we introduce two types of Gompertz equations, where the first type 4-paramater and 3-parameter Gompertz curves do not include the logarithm of the number of individuals, and then we derive 4-parameter and 3-parameter Logistic equations. We notice that Logistic curves are better in modeling bacteria whereas the growth pattern of tumor is described better by Gompertz curves. Increasing the number of parameters of Logistic curves give favorable results for bacteria while decreasing the number …

Go to article

Binary Metrics, Samer Assaf, Tom Cuchta, Matt Insall Apr 2020

Binary Metrics, Samer Assaf, Tom Cuchta, Matt Insall

Mathematics and Statistics Faculty Research & Creative Works

We define a binary metric as a symmetric, distributive lattice ordered magma-valued function of two variables, satisfying a “triangle inequality". Using the notion of a Kuratowski topology, in which topologies are specified by closed sets rather than open sets, we prove that every topology is induced by a binary metric. We conclude with a discussion on the relation between binary metrics and some separation axioms.

Go to article

Many-Body Quantum Dynamics And Induced Correlations Of Bose Polarons, Simeon I. Mistakidis, G. M. Koutentakis, Garyfallia Katsimiga, Th Busch, P. Schmelcher Apr 2020

Many-Body Quantum Dynamics And Induced Correlations Of Bose Polarons, Simeon I. Mistakidis, G. M. Koutentakis, Garyfallia Katsimiga, Th Busch, P. Schmelcher

Physics Faculty Research & Creative Works

We Study The Ground State Properties And Non-Equilibrium Dynamics Of Two Spinor Bosonic Impurities Immersed In A One-Dimensional Bosonic Gas Upon Applying An Interspecies Interaction Quench. For The Ground State Of Two Non-Interacting Impurities We Reveal Signatures Of Attractive Induced Interactions In Both Cases Of Attractive Or Repulsive Interspecies Interactions, While A Weak Impurity-Impurity Repulsion Forces The Impurities To Stay Apart. Turning To The Quench Dynamics We Inspect The Time-Evolution Of The Contrast Unveiling The Existence, Dynamical Deformation And The Orthogonality Catastrophe Of Bose Polarons. We Find That For An Increasing Postquench Repulsion The Impurities Reside In A Superposition Of …

Go to article

Quantum Interference Of K Capture In Energetic G E31+(1s)-Kr Collisions, R. Schuch, Michael Schulz, For Full List Of Authors, See Publisher's Website. Apr 2020

Quantum Interference Of K Capture In Energetic G E31+(1s)-Kr Collisions, R. Schuch, Michael Schulz, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

We have measured characteristic K x rays in coincidence with the scattered particles from collisions of hydrogenlike Ge ions with Kr atoms. The ions were first accelerated to 8.6 MeV/amu, post-stripped to H-like charge state, and decelerated to around 2.5 MeV/amu. From the measurements the probabilities for K-shell to K-shell charge transfer as a function of collision impact parameters were obtained. The probabilities show an onset of oscillations which are interpreted as quantum interference between the K-shell to K-shell electron transfer amplitudes in two spatially separated coupling regions in the incoming and outgoing parts of the collision. The probabilities of …

Go to article

Enhancement And Reentrance Of Spin Triplet Superconductivity In Ute₂ Under Pressure, Sheng Ran, Hyunsoo Kim, I. Lin Liu, Shanta R. Saha, Ian Hayes, Tristin Metz, Yun Suk Eo, Johnpierre Paglione, Nicholas P. Butch Apr 2020

Enhancement And Reentrance Of Spin Triplet Superconductivity In Ute₂ Under Pressure, Sheng Ran, Hyunsoo Kim, I. Lin Liu, Shanta R. Saha, Ian Hayes, Tristin Metz, Yun Suk Eo, Johnpierre Paglione, Nicholas P. Butch

Physics Faculty Research & Creative Works

Spin triplet superconductivity in the Kondo lattice UTe2 appears to be associated with spin fluctuations originating from incipient ferromagnetic order. Here we show clear evidence of twofold enhancement of superconductivity under pressure, which discontinuously transitions to magnetic order, likely of ferromagnetic nature, at higher pressures. The application of a magnetic field tunes the system back across a first-order phase boundary. Straddling this phase boundary, we find another example of reentrant superconductivity in UTe2. As the superconductivity and magnetism exist on two opposite sides of the first-order phase boundary, our results indicate other microscopic mechanisms may be playing …

Go to article

The Microbiota-Gut-Brain Axis Heart Shunt Part I: The French Paradox, Heart Disease And The Microbiota, M. Obrenovich, B. Siddiqui, B. Mccloskey, Prakash Reddy Mar 2020

The Microbiota-Gut-Brain Axis Heart Shunt Part I: The French Paradox, Heart Disease And The Microbiota, M. Obrenovich, B. Siddiqui, B. Mccloskey, Prakash Reddy

Chemistry Faculty Research & Creative Works

It has been well established that a vegetarian and polyphenol-rich diet, including fruits, vegetables, teas, juices, wine, indigestible fiber and whole grains, provide health-promoting phytochemicals and phytonutrients that are beneficial for the heart and brain. What is not well-characterized is the affect these foods have when co-metabolized within our dynamic gut and its colonizing flora. The concept of a heart shunt within the microbiota-gut-brain axis underscores the close association between brain and heart health and the so-called "French paradox" offers clues for understanding neurodegenerative and cerebrovascular diseases. Moreover, oxidation-redox reactions and redox properties of so-called brain and heart-protective foods are …

Go to article

First Prev Next Last