160 Matching Results

Results open in a new window/tab.

Chandra and Magellan/FIRE follow-up observations of PSO167–13: An X-ray weak QSO at z = 6.515

This article presents the results of follow-up observations of the z = 6.515 radio-quiet QSO PSO167–13, which is interacting with a close companion galaxy with the goal to confirm the existence of the X-ray source and to investigate the rest-frame UV properties of the QSO. The authors observed the PSO167–13 system with Chandra/ACIS-S (177 ks) and obtained new spectroscopic observations (7.2 h) with Magellan/FIRE.
Date: May 27, 2021
Creator: Vito, F.; Brandt, William Nielsen; Ricci, F.; Congui, E.; Connor, T.; Bañados, E. et al.
Object Type: Article
System: The UNT Digital Library
Thermal instability and multiphase gas in the simulated interstellar medium with conduction, viscosity, and magnetic fields (open access)

Thermal instability and multiphase gas in the simulated interstellar medium with conduction, viscosity, and magnetic fields

This article uses 2D simulations to investigate thermal instability under the influence of various initial conditions and physical processes.
Date: June 7, 2021
Creator: Jennings, R. Michael & Li, Yuan
Object Type: Article
System: The UNT Digital Library
Weakly Aligned Molecules: From Molecular Detectors to Room-Temperature Tunable Masers (open access)

Weakly Aligned Molecules: From Molecular Detectors to Room-Temperature Tunable Masers

Conference proceeding presenting a new mechanism of manipulation of population in molecular rotational levels in a weakly aligned molecules. Originally presented as an invited talk at the 29th International Laser Physics Workshop held July 19-23, 2021.
Date: July 23, 2021
Creator: Roy, Colin D.; Branković, Zorica & Rostovtsev, Yuri V.
Object Type: Article
System: The UNT Digital Library
Acoustic Metasurface-Aided Broadband Noise Reduction in Automobile Induced by Tire-Pavement Interaction (open access)

Acoustic Metasurface-Aided Broadband Noise Reduction in Automobile Induced by Tire-Pavement Interaction

Article demonstrating a technique utilizing acoustic metasurfaces (AMSes) with high reflective characteristics using relatively lightweight materials for noise reduction without any change in mechanical strength or weight of the tire. The proposed design can significantly reduce the noise arising from tire–pavement interaction over a broadband of acoustic frequencies under 1000 Hz and over a wide range of vehicle speeds using a negative effective dynamic mass density approach.
Date: July 30, 2021
Creator: Heo, Hyeonu; Sofield, Matthew; Ju, Jaehyung & Neogi, Arup
Object Type: Article
System: The UNT Digital Library
Deep Minimum and a Vortex for Positronium Formation in Low-Energy Positron-Helium Collisions (open access)

Deep Minimum and a Vortex for Positronium Formation in Low-Energy Positron-Helium Collisions

This article finds a zero in the positronium formation scattering amplitude and a deep minimum in the logarithm of the corresponding differential cross section for positron–helium collisions for an energy just above the positronium formation threshold. Results show that there is a valley in the logarithm of the positronium formation differential cross section that includes the deep minimum and also a minimum in the forward direction.
Date: August 6, 2021
Creator: Alrowaily, Albandari W.; Quintanilla, Sandra J. & Van Reeth, Peter
Object Type: Article
System: The UNT Digital Library
Collaborative Research: A Systematic and Comprehensive Study of Black Hole-Driven Turbulence in Massive Galactic Systems (open access)

Collaborative Research: A Systematic and Comprehensive Study of Black Hole-Driven Turbulence in Massive Galactic Systems

Data management plan for the grant, "Collaborative Research: A Systematic and Comprehensive Study of Black Hole-Driven Turbulence in Massive Galactic Systems." This research team has developed a technique to measure gas turbulence in systems hosting giant central black holes and will directly evaluate the viability of this mechanism using a large sample of galaxies. This project will deliver a more complete view of the “feedback” provided by accreting SMBHs, leading to a better understanding of the black hole-host galaxy relation. More specifically, it will directly probe the energetics of the intra-cluster, circum-galactic, and interstellar media of massive early-type galaxies.
Date: 2021-09-01/2024-08-31
Creator: Li, Yuan
Object Type: Text
System: The UNT Digital Library
Encapsulated perovskite in NiO nanotube for topological meta-photonic devices (open access)

Encapsulated perovskite in NiO nanotube for topological meta-photonic devices

Data management plan for the grant, "Encapsulated perovskite in NiO nanotube for topological meta-photonic devices." Research studying meta-photonic devices with high absorption and topological photonic devices using encapsulated perovskites in NiO nanotubes. The goal is to achieve high-efficiency solar cells and electrically pumped laser in perovskite/NiO nanotubes patterned in the graded photonic super-crystal. The success of this project will lead to high-efficiency integrated lasers and solar cell devices. It also enhances the abilities in the education arena by enriching program offerings in nanotechnology, clean-energy, and photonics technology.
Date: 2021-09-01/2024-08-31
Creator: Cui, Jingbiao & Lin, Yuankun
Object Type: Text
System: The UNT Digital Library
Advanced modeling of materials with PAOFLOW 2.0: New features and software design (open access)

Advanced modeling of materials with PAOFLOW 2.0: New features and software design

This article describes the recent re-design of the code and the new features and improvements in performance of PAOFLOW, a software tool that constructs tight-binding Hamiltonians from self-consistent electronic wavefunctions by projecting onto a set of atomic orbitals.
Date: September 2, 2021
Creator: Cesaroli, Frank T.; Supka, Andrew; Jayaraj, Anooja; Costa, Marcio; Siloi, Ilaria; Sławińska, Jagoda et al.
Object Type: Article
System: The UNT Digital Library
Simulation of the formation of antihydrogen via magnetobound positronium (open access)

Simulation of the formation of antihydrogen via magnetobound positronium

This article simulates Antihydrogen formation involving magnetobound positronium by computing classical trajectories.
Date: September 9, 2021
Creator: Aguirre, F. F. & Ordonez, Carlos A.
Object Type: Article
System: The UNT Digital Library
A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium (open access)

A Miniature Permanent Magnet Assembly with Localized and Uniform Field with an Application to Optical Pumping of Helium

Article using simulations and experimental measurements to design, build, and test a compact and uniform magnetic field source and then apply it to the optical pumping of atomic helium.
Date: September 24, 2021
Creator: Cameron, Garnet; Cuevas, Jonathan; Pound, Jeffrey Jr. & Shiner, David
Object Type: Article
System: The UNT Digital Library
Cysne et al. Reply (open access)

Cysne et al. Reply

This article is a response to a comment on the authors' original article "Disentangling Orbital and Valley Hall Effects in Bilayers of Transition Metal Dichalcogenides." The authors' response concludes that they do not believe the main points of the original Letter are affected by the Comment.
Date: October 1, 2021
Creator: Cysne, Tarik P.; Costa, Marcio; Canonico, Luis M.; Buongiorno Nardelli, Marco; Muniz, R. B. & Rappoport, Tatiana G.
Object Type: Article
System: The UNT Digital Library
Sub-Diffraction-Limit Imaging System with two Interfacing Hyperbolic Metamaterials (open access)

Sub-Diffraction-Limit Imaging System with two Interfacing Hyperbolic Metamaterials

Article demonstrating that a system of two interfacing hyperbolic metamaterials may be used for direct subwavelength imaging in the visible range.
Date: October 27, 2021
Creator: Bronnikov, Kirill; Arriaga, J.; Krokhin, Arkadii A. & Drachev, Vladimir P.
Object Type: Article
System: The UNT Digital Library
Ice imaging in aircraft anti-icing fluid films using polarized light (open access)

Ice imaging in aircraft anti-icing fluid films using polarized light

Article presents how to enhance ice contrast in the visible spectrum by using ice birefringence and polarized light reflection. The method can be used for both visual inspection and automatic ice detection systems.
Date: December 13, 2021
Creator: Grishaev, Viktor G.; Usachev, Igor A.; Drachev, Vladimir P.; Gattarov, Ramil K.; Rudenko, Nadezhda I.; Amirfazli, Alidad et al.
Object Type: Article
System: The UNT Digital Library
The allometric propagation of COVID-19 is explained by human travel (open access)

The allometric propagation of COVID-19 is explained by human travel

Article develops an allometric model capable of fitting the initial phase of the COVID-19 pandemic and predicting the propagation of the illness for up to 100 days.
Date: December 18, 2021
Creator: Tuladhar, Rohisha; Grigolini, Paolo & Santamaria, Fidel
Object Type: Article
System: The UNT Digital Library
Optimization of the Observing Cadence for the Rubin Observatory Legacy Survey of Space and Time: A Pioneering Process of Community-focused Experimental Design (open access)

Optimization of the Observing Cadence for the Rubin Observatory Legacy Survey of Space and Time: A Pioneering Process of Community-focused Experimental Design

This article is part of a Focus Issue on the topic of Rubin LSST Survey Strategy Optimization. The motivation, history, and decision-making process of the observing strategy optimization are detailed, giving context to the science-driven proposals and recommendations for the survey strategy included in this Focus Issue.
Date: December 22, 2021
Creator: Bianco, Federica B.; Ivezić, Željko; Jones, R. Lynne; Graham, Melissa L.; Marshall, Phil; Saha, Abhijit et al.
Object Type: Article
System: The UNT Digital Library
Two-Layer High-Throughput: Effective Mass Calculations Including Warping (open access)

Two-Layer High-Throughput: Effective Mass Calculations Including Warping

Article performing and analyzing two-layer high-throughput calculations.
Date: February 26, 2022
Creator: Supka, Andrew; Mecholsky, Nicholas A.; Buongiorno Nardelli, Marco; Curtarolo, Stefano & Fornari, Marco
Object Type: Article
System: The UNT Digital Library
Relaxation time approximations in PAOFLOW 2.0 (open access)

Relaxation time approximations in PAOFLOW 2.0

Article presents the implementation of relaxation time approximation models in the calculation of Boltzmann transport in PAOFLOW 2.0 and applies those to model band-structures. In addition, using a self-consistent fitting of the model parameters to experimental conductivity data, the authors provide a flexible tool to extract scattering rates with high accuracy. They illustrate the approximations using simple models and then apply the method to GaAs, Si, Mg₃Sb₂, and CoSb₃.
Date: March 23, 2022
Creator: Jayaraj, Anooja; Siloi, Ilaria; Fornari, Marco & Buongiorno Nardelli, Marco
Object Type: Article
System: The UNT Digital Library
Connecting Low- and High-redshift Weak Emission-line Quasars via Hubble Space Telescope Spectroscopy of Lyα Emission (open access)

Connecting Low- and High-redshift Weak Emission-line Quasars via Hubble Space Telescope Spectroscopy of Lyα Emission

Article presents ultraviolet spectroscopy covering the Lyα + N v complex of six candidate low-redshift (0.9 < z < 1.5) weak emission-line quasars (WLQs) based on observations with the Hubble Space Telescope.
Date: April 14, 2022
Creator: Paul, Jeremiah D.; Plotkin, Richard M.; Shemmer, Ohad; Anderson, Scott F.; Brandt, W. N.; Fan, Xiaohui et al.
Object Type: Article
System: The UNT Digital Library
Momentum-Space Spin Antivortex and Spin Transport in Monolayer Pb (open access)

Momentum-Space Spin Antivortex and Spin Transport in Monolayer Pb

This article finds a nontrivial spin texture, spin antivortex, can appear at certain momenta on the Γ− K line in a 2D monolayer Pb on top of SiC.
Date: April 21, 2022
Creator: Yang, Kaijie; Wang, Yuanxi & Liu, Chao-Xing
Object Type: Article
System: The UNT Digital Library
Discovery of the first heavily obscured QSO candidate at z > 6 in a close galaxy pair (open access)

Discovery of the first heavily obscured QSO candidate at z > 6 in a close galaxy pair

This article reports the Chandra discovery of the first heavily obscured QSO candidate in the early universe, hosted by a close (≈5 kpc) galaxy pair at z = 6.515.
Date: May 17, 2022
Creator: Vito, F.; Brandt, William Nielsen; Bauer, Franz E.; Gilli, Roberto; Luo, B.; Zamorani, G. et al.
Object Type: Article
System: The UNT Digital Library
Can X-Ray Observations Improve Optical-UV-based Accretion-rate Estimates for Quasars? (open access)

Can X-Ray Observations Improve Optical-UV-based Accretion-rate Estimates for Quasars?

Article presents a study utilizing a carefully selected sample of 53 radio-quiet quasars that have Hβ and C iv λ1549 spectroscopy as well as Chandra coverage, to search for a robust accretion-rate indicator for quasars, particularly at the highest-accessible redshifts (z ∼ 6–7).
Date: May 23, 2022
Creator: Marlar, Andrea
Object Type: Article
System: The UNT Digital Library
Exploring Changes in Quasar Spectral Energy Distributions across C iv Parameter Space (open access)

Exploring Changes in Quasar Spectral Energy Distributions across C iv Parameter Space

This article examines the UV/X-ray properties of 1378 quasars in order to link empirical correlations to theoretical models of the physical mechanisms dominating quasars as a function of mass and accretion rate.
Date: June 6, 2022
Creator: Rivera, Angelica B.; Richards, Gordon T.; Gallagher, Sarah C.; McCaffrey, Trevor V.; Rankine, Amy L.; Hewett, Paul C. et al.
Object Type: Article
System: The UNT Digital Library
Quantum algorithm for electronic band structures with local tight-binding orbitals (open access)

Quantum algorithm for electronic band structures with local tight-binding orbitals

Article says that while the main thrust of quantum computing research in materials science is to accurately measure the classically intractable electron correlation effects due to Coulomb repulsion, designing optimal quantum algorithms for simpler problems with well-understood solutions is a useful tactic to advance our quantum “toolbox”. In this paper, the authors adopt a direct space approach, using a novel hybrid first/second-quantized qubit mapping which allows us to construct a single Hamiltonian, and a single cost-function, suitable for solving the entire electronic band structure.
Date: June 14, 2022
Creator: Sherbert, Kyle; Jayaraj, Anooja & Buongiorno Nardelli, Marco
Object Type: Article
System: The UNT Digital Library
Connecting Galaxies and Supermassive Black Holes: Meso-scale Simulations of Multiphase Accretion Flows (open access)

Connecting Galaxies and Supermassive Black Holes: Meso-scale Simulations of Multiphase Accretion Flows

Data management plan for the grant, "Connecting Galaxies and Supermassive Black Holes: Meso-scale Simulations of Multiphase Accretion Flows." It proposes to study how gas flows onto the supermassive black holes in massive galaxies and galaxy clusters. They will perform numerical simulations with a nested zoom-in technique, focusing on the mesoscale accretion flows from the Bondi radius to hundreds of Schwarzschild radii. They will predict the mass flux of different phases, as well as their angular momentum and magnetic flux.
Date: 2022-07-01/2025-06-30
Creator: Li, Yuan
Object Type: Text
System: The UNT Digital Library