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Faculty Publications

2019

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Articles 31 - 60 of 62

Full-Text Articles in Physics

3d Plasmonic Design Approach For Efficient Transmissive Huygens Metasurfaces, Bryan M. Adomanis, D. Bruce Burckel, Michael A. Marciniak Jul 2019

3d Plasmonic Design Approach For Efficient Transmissive Huygens Metasurfaces, Bryan M. Adomanis, D. Bruce Burckel, Michael A. Marciniak

Faculty Publications

In this paper we present a design concept for 3D plasmonic scatterers as high- efficiency transmissive metasurface (MS) building blocks. A genetic algorithm (GA) routine partitions the faces of the walls inside an open cavity into a M x N grid of voxels which can be either covered with metal or left bare, and optimizes the distribution of metal coverage needed to generate electric and magnetic modes of equal strength with a targeted phase delay (Φt) at the design wavelength. Even though the electric and magnetic modes can be more complicated than typical low order modes, with their spectral overlap …


Effect Of Strain On Charge Density Wave Order In The Holstein Model, Benjami Cohen-Stead, Natanael Costa, Ehsan Khatami, Richard Scalettar Jul 2019

Effect Of Strain On Charge Density Wave Order In The Holstein Model, Benjami Cohen-Stead, Natanael Costa, Ehsan Khatami, Richard Scalettar

Faculty Publications

We investigate charge ordering in the Holstein model in the presence of anisotropic hopping, tx,ty=1-δ,1+δ, as a model of the effect of strain on charge-density-wave (CDW) materials. Using quantum Monte Carlo simulations, we show that the CDW transition temperature is relatively insensitive to moderate anisotropy δ 0.3, but begins to decrease more rapidly at δ 0.4. However, the density correlations, as well as the kinetic energies parallel and perpendicular to the compressional axis, change significantly for moderate δ. Accompanying mean-field theory calculations show a similar qualitative structure, with the transition temperature relatively constant at small δ, and a more rapid …


New Constraints On Early-Type Galaxy Assembly From Spectroscopic Metallicities Of Globular Clusters In M87, Alexa Villaume, Aaron Romanowsky, Jean Brodie, Jay Strader Jul 2019

New Constraints On Early-Type Galaxy Assembly From Spectroscopic Metallicities Of Globular Clusters In M87, Alexa Villaume, Aaron Romanowsky, Jean Brodie, Jay Strader

Faculty Publications

The observed characteristics of globular cluster (GC) systems, such as metallicity distributions, are commonly used to place constraints on galaxy formation models. However, obtaining reliable metallicity values is particularly difficult because of our limited means to obtain high quality spectroscopy of extragalactic GCs. Often, "color–metallicity relations" are invoked to convert easier-to-obtain photometric measurements into metallicities, but there is no consensus on what form these relations should take. In this paper we make use of multiple photometric data sets and iron metallicity values derived from applying full-spectrum stellar population synthesis models to deep Keck/LRIS spectra of 177 GCs centrally located around …


High-Harmonic Spectroscopy Of Transient Two-Center Interference Calculated With Time-Dependent Density-Functional Theory, Francois Mauger, Paul M. Abanador, Kenneth Lopata, Kenneth J. Schafer Jul 2019

High-Harmonic Spectroscopy Of Transient Two-Center Interference Calculated With Time-Dependent Density-Functional Theory, Francois Mauger, Paul M. Abanador, Kenneth Lopata, Kenneth J. Schafer

Faculty Publications

We demonstrate high-harmonic spectroscopy in many-electron molecules using time-dependent density-functional theory. We show that a weak attosecond-pulse-train ionization seed that is properly synchronized with the strong driving mid-infrared laser field can produce experimentally relevant high-harmonic generation (HHG) signals, from which we extract both the spectral amplitude and the target-specific phase (group delay). We also show that further processing of the HHG signal can be used to achieve molecular-frame resolution, i.e., to resolve the contributions from rescattering on different sides of an oriented molecule. In this framework, we investigate transient two-center interference in CO2 and OCS, and how subcycle polarization effects …


Nuclear Engineering At The Air Force Institute Of Technology: A Unique Graduate School Experience For A Unique Set Of Students, Michael B. Shattan Jul 2019

Nuclear Engineering At The Air Force Institute Of Technology: A Unique Graduate School Experience For A Unique Set Of Students, Michael B. Shattan

Faculty Publications

In August 2018, the Air University Commander formed a task force to review the Air Force’s Science, Technology, Engineering, and Mathematics (STEM) graduate education programs that are delivered and administered through the Air Force Institute of Technology (AFIT). The study was rooted in strategies to support the 2018 National Defense Strategy, and provided the necessary technologically equipped personnel for the 21st century. The study was commonly referred to as “reimagining AFIT”. Several themes emerged from the study, which include reaching a broader community of Airmen through alternate educational modes (e.g. distance learning, short course etc.), forming strategic educational and research …


Spatially Resolved Stellar Populations And Kinematics With Kcwi: Probing The Assembly History Of The Massive Early-Type Galaxy Ngc 1407, Anna Ferré-Mateu, Duncan Forbes, Richard Mcdermid, Aaron Romanowsky, Jean Brodie Jun 2019

Spatially Resolved Stellar Populations And Kinematics With Kcwi: Probing The Assembly History Of The Massive Early-Type Galaxy Ngc 1407, Anna Ferré-Mateu, Duncan Forbes, Richard Mcdermid, Aaron Romanowsky, Jean Brodie

Faculty Publications

Using the newly commissioned Keck Cosmic Web Imager (KCWI) instrument on the Keck II telescope, we analyze the stellar kinematics and stellar populations of the well-studied massive early-type galaxy (ETG) NGC 1407. We obtained high signal-to-noise integral field spectra for a central and an outer (around one effective radius toward the southeast direction) pointing with integration times of just 600 s and 2400 s, respectively. We confirm the presence of a kinematically distinct core also revealed by VLT/MUSE data of the central regions. While NGC 1407 was previously found to have stellar populations characteristic of massive ETGs (with radially constant …


Transverse Momentum Dependent Production Cross Sections Of Chargedpions, Kaons And Protons Produced In Inclusive E+ E Annihilation At √S = 10.58 Gev, R. Seidl, I. Adachi, J. K. Ahn, H. Aihara, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, A. M. Bakich, V. Bansal, P. Behera, C. Beleño, M. Berger, V. Bhardwaj, T. Bilka, J. Biswal, A. Bobrov, A. Bozek, M. Bračko, L. Cao, Milind Purohit, Et. Al. Jun 2019

Transverse Momentum Dependent Production Cross Sections Of Chargedpions, Kaons And Protons Produced In Inclusive E+ E− Annihilation At √S = 10.58 Gev, R. Seidl, I. Adachi, J. K. Ahn, H. Aihara, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, A. M. Bakich, V. Bansal, P. Behera, C. Beleño, M. Berger, V. Bhardwaj, T. Bilka, J. Biswal, A. Bobrov, A. Bozek, M. Bračko, L. Cao, Milind Purohit, Et. Al.

Faculty Publications

We report measurements of the production cross sections of charged pions, kaons, and protons as a function of fractional energy, the event-shape variable called thrust, and the transverse momentum with respect to the thrust axis. These measurements access the transverse momenta created in the fragmentation process, which are of critical importance to the understanding of any transverse-momentum-dependent distribution and fragmentation functions. The low transverse-momentum part of the cross sections can be well described by Gaussians in transverse momentum as is generally assumed but the fractional-energy dependence is nontrivial and different hadron types have varying Gaussian widths. The width of these …


Generating Dark And Antidark Beams Using The Genuine Cross-Spectral Density Function Criterion, Milo W. Hyde Iv, Svetlana Avramov-Zamurovic Jun 2019

Generating Dark And Antidark Beams Using The Genuine Cross-Spectral Density Function Criterion, Milo W. Hyde Iv, Svetlana Avramov-Zamurovic

Faculty Publications

In this work, we demonstrate how to generate dark and antidark beams—diffraction-free partially coherent sources—using the genuine cross-spectral density function criterion. These beams have been realized in prior work using the source’s coherent-mode representation and by transforming a J0-Bessel correlated partially coherent source using a wavefront-folding interferometer. We generalize the traditional dark and antidark beams to produce higher-order sources, which have not been realized. We simulate the generation of these beams and compare the results to the corresponding theoretical predictions. The simulated results are found to be in excellent agreement with theory, thus validating our analysis. We discuss …


Bounds On Vacuum-Orthogonal Lorentz And Cpt Violation From Radiative Corrections, Brett Altschul Jun 2019

Bounds On Vacuum-Orthogonal Lorentz And Cpt Violation From Radiative Corrections, Brett Altschul

Faculty Publications

Certain forms of Lorentz violation in the photon sector are difficult to bound directly, since they are “vacuum orthogonal”—meaning they do not change the solutions of the equations of motion in vacuum. However, these very same terms have a unique tendency to contribute large radiative corrections to effects in other sectors. Making use of this, we set bounds on four previously unconstrained d = 5 photon operators at the 10 − 25 – 10 − 31 GeV − 1 levels.


There Is No Ambiguity In The Radiatively Induced Gravitational Chern-Simons Term, Brett Altschul Jun 2019

There Is No Ambiguity In The Radiatively Induced Gravitational Chern-Simons Term, Brett Altschul

Faculty Publications

Quantum corrections to Lorentz- and C P T -violating QED in flat spacetime produce unusual radiative corrections, which can be finite but of undetermined magnitude. The corresponding radiative corrections in a gravitational theory are even stranger, since the term in the fermion action involving a preferred axial vector b μ would give rise to a gravitational Chern-Simons term that is proportional b μ , yet which actually does not break Lorentz invariance. Initially, the coefficient of this gravitational Chern-Simons term appears to have the same ambiguity as the coefficient for the analogous term in QED. However, this puzzle is resolved …


Experimental Evidence Supportive Of The Quantum Dna Model, F. Matthew Mihelic May 2019

Experimental Evidence Supportive Of The Quantum Dna Model, F. Matthew Mihelic

Faculty Publications

The DNA molecule can be modeled as a quantum logic processor in which electron spin qubits are held coherently in each nucleotide in a logically and thermodynamically reversible enantiomeric symmetry, and can be coherently conducted along the pi-stacking interactions of aromatic nucleotide bases, while simultaneously being spin-filtered via the helicity of the DNA molecule. Entangled electron pairs can be separated by that spin-filtering, held coherently at biological temperatures in the topologically insulated nucleotide quantum gates, and incorporated into separate DNA strands during DNA replication. Two separate DNA strands that share quantum entangled electrons can be mitotically divided into individual cells, …


Numerical Linked-Cluster Expansions For Disordered Lattice Models, M. D. Mulanix, Demetrius Almada, Ehsan Khatami May 2019

Numerical Linked-Cluster Expansions For Disordered Lattice Models, M. D. Mulanix, Demetrius Almada, Ehsan Khatami

Faculty Publications

Imperfections in correlated materials can alter their ground state as well as finite-temperature properties in significant ways. Here, we develop a method based on numerical linked-cluster expansions for calculating exact finite-temperature properties of disordered lattice models directly in the thermodynamic limit. We show that a continuous distribution for disordered parameters can be achieved using a set of carefully chosen discrete modes in the distribution, which allows for the averaging of properties over all disorder realizations. We benchmark our results for thermodynamic properties of the square-lattice Ising and quantum Heisenberg models with bond disorder against Monte Carlo simulations and study them …


Fluctuating Hydrodynamics Of Electrolytes At Electroneutral Scales, Aleksandar Donev, Andrew Nonaka, Changho Kim, Alejandro Garcia, John Bell Apr 2019

Fluctuating Hydrodynamics Of Electrolytes At Electroneutral Scales, Aleksandar Donev, Andrew Nonaka, Changho Kim, Alejandro Garcia, John Bell

Faculty Publications

At mesoscopic scales electrolyte solutions are modeled by the fluctuating generalized Poisson-Nernst-Planck (PNP) equations [J.-P. Péraud et al., Phys. Rev. Fluids 1, 074103 (2016)]. However, at length and time scales larger than the Debye scales, electrolytes are effectively electroneutral and the charged-fluid PNP equations become too stiff to solve numerically. Here we formulate the isothermal incompressible equations of fluctuating hydrodynamics for reactive multispecies mixtures involving charged species in the electroneutral limit and design a numerical algorithm to solve these equations. Our model does not assume a dilute electrolyte solution but rather treats all species on an equal footing, accounting for …


Bounds On Vacuum-Orthogonal Lorentz And Cpt Violation From Radiative Corrections, Brett David Altschul Apr 2019

Bounds On Vacuum-Orthogonal Lorentz And Cpt Violation From Radiative Corrections, Brett David Altschul

Faculty Publications

Certain forms of Lorentz violation in the photon sector are difficult to bound directly, since they are “vacuum orthogonal”—meaning they do not change the solutions of the equations of motion in vacuum. However, these very same terms have a unique tendency to contribute large radiative corrections to effects in other sectors. Making use of this, we set bounds on four previously unconstrained d=5 photon operators at the 10−25–10−31  GeV−1 levels.


There Is No Ambiguity In The Radiatively Induced Gravitational Chern-Simons Term, Brett David Altschul Mar 2019

There Is No Ambiguity In The Radiatively Induced Gravitational Chern-Simons Term, Brett David Altschul

Faculty Publications

Quantum corrections to Lorentz- and CPT-violating QED in flat spacetime produce unusual radiative corrections, which can be finite but of undetermined magnitude. The corresponding radiative corrections in a gravitational theory are even stranger, since the term in the fermion action involving a preferred axial vector bμ would give rise to a gravitational Chern-Simons term that is proportional bμ, yet which actually does not break Lorentz invariance. Initially, the coefficient of this gravitational Chern-Simons term appears to have the same ambiguity as the coefficient for the analogous term in QED. However, this puzzle is resolved by the fact that …


Partially Coherent Sources Generated From The Incoherent Sum Of Fields Containing Random-Width Bessel Functions, Milo W. Hyde Iv Mar 2019

Partially Coherent Sources Generated From The Incoherent Sum Of Fields Containing Random-Width Bessel Functions, Milo W. Hyde Iv

Faculty Publications

Using the criterion for a genuine cross-spectral density function, we demonstrate the realization of an ??-Bessel correlated source, which has only recently been achieved using the source’s coherent-mode representation. In addition, with just a simple change, we create a whole new class of partially coherent sources that have not been realized. We simulate the generation of these sources and compare the results to theoretical predictions to validate our analysis. The partially coherent sources described herein can easily be synthesized using spatial light modulators, and the approach presented in this Letter can be used to design sources for optical trapping, optical …


A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter Van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky Mar 2019

A Second Galaxy Missing Dark Matter In The Ngc 1052, Pieter Van Dokkum, Shany Danieli, Roberto Abraham, Charlie Conroy, Aaron Romanowsky

Faculty Publications

The ultra-diffuse galaxy NGC1052-DF2 has a very low velocity dispersion, indicating that it has little or no dark matter. Here we report the discovery of a second galaxy in this class, residing in the same group. NGC1052-DF4 closely resembles NGC1052-DF2 in terms of its size, surface brightness, and morphology; has a similar distance of Dsbf =  19.9 2.8 Mpc; and also has a population of luminous globular clusters extending out to 7 kpc from the center of the galaxy. Accurate radial velocities of the diffuse galaxy light and seven of the globular clusters were obtained with the Low Resolution …


Shaping The Far-Zone Intensity, Degree Of Polarization, Angle Of Polarization, And Ellipticity Angle Using Vector Schell-Model Sources, Milo W. Hyde Iv Mar 2019

Shaping The Far-Zone Intensity, Degree Of Polarization, Angle Of Polarization, And Ellipticity Angle Using Vector Schell-Model Sources, Milo W. Hyde Iv

Faculty Publications

This paper presents a method to control both the shape and polarization of a beam in the far field using a vector Schell-model source. Given a desired far-zone beam shape and polarization, and applying Fourier and statistical optics theory, we derive the requisite second-order moments of said source, discuss what aspects of the far-zone beam can be controlled, and develop a step-by-step procedure for synthesizing the required random vector field instances. We validate this approach with Monte-Carlo wave-optics simulations. The results are found to be in very good agreement with the desired far-zone beam characteristics. The beam-shaping technique developed in …


Structure And Magnetism Of Nifemngaxsn1-X (X=0, 0.25, 0.5, 0.75, 1.00) Heusler Compounds, Jace Waybright, Lee Halbritter, Bishnu Dahal, Hanyang Qian, Yung Huh, Pavel Lukashev, Parashu Kharel Mar 2019

Structure And Magnetism Of Nifemngaxsn1-X (X=0, 0.25, 0.5, 0.75, 1.00) Heusler Compounds, Jace Waybright, Lee Halbritter, Bishnu Dahal, Hanyang Qian, Yung Huh, Pavel Lukashev, Parashu Kharel

Faculty Publications

The crystal structure and magnetic properties of NiFeMnGaxSn1-x (x = 0, 0.25, 0.50, 0.75 and 1.00) Heusler compounds have been investigated experimentally and theoretically. The computational results suggest that NiFeMnGa0.75Sn0.25 is nearly half-metallic with a spin polarization P of 87%. The bulk samples prepared using arc-melting and annealing exhibit a high degree of Y-type order. All the investigated samples show ferromagnetic spin order with the Curie temperatures ranging from 284 K for NiFeMnGa to 408 K for NiFeMnSn. The intermediate composition NiFeMnGa0.75Sn0.25, which is predicted to be nearly half metallic, …


A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak Feb 2019

A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak

Faculty Publications

The realization of Internet of Underground Things (IOUT) relies on the establishment of reliable communication links, where the antenna becomes a major design component due to the significant impacts of soil. In this paper, a theoretical model is developed to capture the impacts of change of soil moisture on the return loss, resonant frequency, and bandwidth of a buried dipole antenna. Experiments are conducted in silty clay loam, sandy, and silt loam soil, to characterize the effects of soil, in an indoor testbed and field testbeds. It is shown that at subsurface burial depths (0.1-0.4m), change in soil moisture impacts …


Observation Of The Decay D0 → K Π + E + E , J.P. Lees, P. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, Milind Purohit, Et. Al. Feb 2019

Observation Of The Decay D0 → K− Π + E + E −, J.P. Lees, P. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, Milind Purohit, Et. Al.

Faculty Publications

We report the observation of the rare charm decay D0 → K−πþeþe−, based on 468 fb−1 of eþe− annihilation data collected at or close to the center-of-mass energy of the ϒð4SÞ resonance with the BABAR detector at the SLAC National Accelerator Laboratory. We find the branching fraction in the invariant mass range 0.675 < m(e+e) < 0.875 GeV=c2 of the electron-positron pair to be B(D0 → K−π+e+e) = (4.0 ± 0.5 ± 0.2 ± 0.1) × 10−6, where the first uncertainty is statistical, the second …


Search For A Stable Six-Quark State At Babar, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, Milind Purohit Feb 2019

Search For A Stable Six-Quark State At Babar, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu G. Kolomensky, M. Fritsch, H. Koch, T. Schroeder, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, V. B. Golubev, Milind Purohit

Faculty Publications

Recent investigations have suggested that the six-quark combination uuddss could be a deeply bound state (S) that has eluded detection so far, and a potential dark matter candidate. We report the first search for a stable, doubly strange six-quark state in ϒ → SΛ¯ Λ¯ decays based on a sample of 90 × 106ϒ(2S) and 110 × 106ϒ(3S) decays collected by the BABAR experiment. No signal is observed, and 90% confidence level limits on the combined ϒ(2S; 3S) → SΛ¯ Λ¯ branching fraction in the range (1.2–1.4) × 10−7 are derived for m …


Near Earth Space Object Detection Using Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins, Stephen C. Cain, David J. Becker Feb 2019

Near Earth Space Object Detection Using Parallax As Multi-Hypothesis Test Criterion, Joseph C. Tompkins, Stephen C. Cain, David J. Becker

Faculty Publications

The US Strategic Command (USSTRATCOM) operated Space Surveillance Network (SSN) is tasked with Space Situational Awareness (SSA) for the U.S. military. This system is made up of Electro-Optic sensors, such as the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) and RADAR based sensors, such as the Space Fence Gaps. They remain in the tracking of Resident Space Objects (RSO’s) in Geosynchronous Orbits (GEO), due to limitations of SST and GEODSS system implementation. This research explores a reliable, ground-based technique used to quickly determine an RSO’s altitude from a single or limited set of observations. Implementation of such sensors into the SSN …


Experimental Study: Underwater Propagation Of Super-Gaussian And Multi-Gaussian Schell-Model Partially Coherent Beams With Varying Degrees Of Spatial Coherence, Svetlana Avramov-Zamurovic, Charles L. Nelson, Milo W. Hyde Iv Feb 2019

Experimental Study: Underwater Propagation Of Super-Gaussian And Multi-Gaussian Schell-Model Partially Coherent Beams With Varying Degrees Of Spatial Coherence, Svetlana Avramov-Zamurovic, Charles L. Nelson, Milo W. Hyde Iv

Faculty Publications

We report on experiments where super-Gaussian and flat-top, multi-Gaussian Schell-model spatially partially coherent beams, with varying degrees of spatial coherence, were propagated underwater. Two scenarios were explored—calm and mechanically agitated water. The main objective of our study was the experimental comparison of the scintillation statistics. For a similar degree of coherence widths, the results show a potentially improved performance of scintillation index for the multi-Gaussian Schell-model beams as compared to the super-Gaussian beams. It should be noted that the presented results pertain only to the given experimental scenarios and further investigation is necessary to determine the scope of the findings.


Β-Decay Half-Lives Of Neutron-Rich Nuclides In The A = 100 – 110 Mass Region, A. C. Dombos, A. Spyrou, F. Naqvi, S. J. Quinn, S. N. Liddick, A. Algora, T. Baumann, J. Brett, B. P. Crider, P. A. Deyoung, T. Ginter, J. Gombas, E. Kwan, S. Lyons, W.-J. Ong, A. Palmisano, J. Pereira, C. J. Prokop, D. P. Scriven, A. Simon, M. K. Smith, C. S. Sumithrarachchi Jan 2019

Β-Decay Half-Lives Of Neutron-Rich Nuclides In The A = 100 – 110 Mass Region, A. C. Dombos, A. Spyrou, F. Naqvi, S. J. Quinn, S. N. Liddick, A. Algora, T. Baumann, J. Brett, B. P. Crider, P. A. Deyoung, T. Ginter, J. Gombas, E. Kwan, S. Lyons, W.-J. Ong, A. Palmisano, J. Pereira, C. J. Prokop, D. P. Scriven, A. Simon, M. K. Smith, C. S. Sumithrarachchi

Faculty Publications

β-decay half-lives of neutron-rich nuclides in the A = 100–110 mass region have been measured using an implantation station installed inside of the Summing NaI(Tl) (SuN) detector at the National Superconducting Cyclotron Laboratory. Accurate half-lives for these nuclides are important for nuclear astrophysics, nuclear structure, and nuclear technology. The half-lives from the present work are compared with previous measurements, showing overall good agreement.


Results From The Cuore Experiment †, Alessio Caminata, Douglas Adams, Chris Alduino, Krystal Alfonso, Frank Avignone Iii, Oscar Azzolini, Giacomo Bari, Fabio Bellini, Giovanni Benato, Andrea Bersani, Matteo Biassoni, Antonio Branca, Chiara Brofferio, Carlo Bucci, Alice Campani, Lucia Canonica, Xi-Guang Cao, Silvia Capelli, Luigi Cappelli, Laura Cardani, Paolo Carniti, Et. Al. Jan 2019

Results From The Cuore Experiment †, Alessio Caminata, Douglas Adams, Chris Alduino, Krystal Alfonso, Frank Avignone Iii, Oscar Azzolini, Giacomo Bari, Fabio Bellini, Giovanni Benato, Andrea Bersani, Matteo Biassoni, Antonio Branca, Chiara Brofferio, Carlo Bucci, Alice Campani, Lucia Canonica, Xi-Guang Cao, Silvia Capelli, Luigi Cappelli, Laura Cardani, Paolo Carniti, Et. Al.

Faculty Publications

The Cryogenic Underground Observatory for Rare Events (CUORE) is the first bolometric experiment searching for neutrinoless double beta decay that has been able to reach the 1-ton scale. The detector consists of an array of 988 TeO2 crystals arranged in a cylindrical compact structure of 19 towers, each of them made of 52 crystals. The construction of the experiment was completed in August 2016 and the data taking started in spring 2017 after a period of commissioning and tests. In this work we present the neutrinoless double beta decay results of CUORE from examining a total TeO2 exposure …


Ground State Phase Diagram Of The One-Dimensional Bose-Hubbard Model From Restricted Boltzmann Machines, Kristopher Mcbrian, Giuseppe Carleo, Ehsan Khatami Jan 2019

Ground State Phase Diagram Of The One-Dimensional Bose-Hubbard Model From Restricted Boltzmann Machines, Kristopher Mcbrian, Giuseppe Carleo, Ehsan Khatami

Faculty Publications

Motivated by recent advances in the representation of ground state wavefunctions of quantum many-body systems using restricted Boltzmann machines as variational ansatz, we utilize an open-source platform for constructing such ansatz called NetKet to explore the extent of applicability of restricted Boltzmann machines to bosonic lattice models. Within NetKet, we design and train these machines for the one-dimensional Bose-Hubbard model through a Monte Carlo sampling of the Fock space. We vary parameters such as the strength of the onsite repulsion, the chemical potential, the system size and the maximum site occupancy and use converged equations of state to identify phase …


Laser-Induced Plasma Analysis For Surrogate Nuclear Debris, Michael B. Shattan, John Auxier, A. C. Stowe, Christian G. Parigger Jan 2019

Laser-Induced Plasma Analysis For Surrogate Nuclear Debris, Michael B. Shattan, John Auxier, A. C. Stowe, Christian G. Parigger

Faculty Publications

This work identifies analytical lines in laser-induced plasma for chemical analyses of major elements found in surrogate nuclear debris. These lines are evaluated for interferences and signal strength to insure they would be useful to measure relative concentrations. Compact, portable instruments are employed and can be included as part of a mobile nuclear forensics laboratory for field screening of nuclear debris and contamination. The average plasma temperature is measured using the well-established Boltzmann plot technique, and plasma's average electron density is determined using empirical formulae based on Stark broadening of the H-alpha line. These measurements suggest existence of partial local …


M2 Factor Of A Vector Schell-Model Beam, Milo W. Hyde Iv, Mark F. Spencer Jan 2019

M2 Factor Of A Vector Schell-Model Beam, Milo W. Hyde Iv, Mark F. Spencer

Faculty Publications

Extending existing scalar Schell-model source work, we derive the M2 factor for a general electromagnetic or vector Schell-model source to assess beam quality. In particular, we compute the M2 factors for two vector Schell-model sources found in the literature. We then describe how to synthesize vector Schell-model beams in terms of specified, desired M2 and present Monte Carlo simulation results to validate our analysis.


Variations Of Heavy Ion Abundances Relative To Proton Abundances In Large Solar Energetic (E > 10 Mev) Particle Events, J. F. Round, Robert D. Loper, Omar A. Nava, Stephen W. Kahler Jan 2019

Variations Of Heavy Ion Abundances Relative To Proton Abundances In Large Solar Energetic (E > 10 Mev) Particle Events, J. F. Round, Robert D. Loper, Omar A. Nava, Stephen W. Kahler

Faculty Publications

The elemental composition of heavy ions (with atomic number Z > 2) (hi-Z) in large gradual E > 10 MeV nuc-1 SEP events has been extensively studied in the 2-15 MeV nuc-1 range to determine the acceleration processes and transport properties of SEPs. These studies invariably are based on abundances relative to those of a single element such as C or O and often neglect H and He, the elements of primary interest for space weather. The total radiation of an SEP event is determined not only by the H and He properties but also by those of hi-Z ions …