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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Energy levels, oscillator strengths, radiative decay rates, and fine-structure collision strengths for the Zn-like ions Nb XII and Mo XIII

Energy levels, line strengths, oscillator strengths, radiative decay rates, and fine-structure collision strengths are presented for the Zn-like ions Nb XII and Mo XIII. The atomic data are calculated with the AUTOSTRUCTURE code, where relativistic corrections are introduced according to the Breit–Pauli distorted wave approach. We present the calculations of atomic data for 110 fine-structure levels generated from fifteen configurations (1s{sup 2}2s{sup 2}2p{sup 6}3s{sup 2}3p{sup 6}3d{sup 10})4s{sup 2}, 4s4p, 4p{sup 2}, 4s4d, 4s4f, 4s5s, 4p4d, 4s5p, 4s5d, 4p4f, 4p5s, 4d{sup 2}, 4d4f, 4f{sup 2}, and 3d{sup 9}4s{sup 2}4p. Fine-structure collision strengths for transitions from the ground and the first four excited levels are presented at six electron energies (20, 50, 80, 110, 150, and 180 Ryd). Our atomic structure data are compared with the available experimental and theoretical results.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2012

ARRA-Multi-Level Energy Storage and Controls for Large-Scale Wind Energy Integration

The Project Objective is to design innovative energy storage architecture and associated controls for high wind penetration to increase reliability and market acceptance of wind power. The project goals are to facilitate wind energy integration at different levels by design and control of suitable energy storage systems. The three levels of wind power system are: Balancing Control Center level, Wind Power Plant level, and Wind Power Generator level.

17 WIND ENERGY↗
DOE OSTI2021

Charge Transfer Screening and Energy Level Alignment at Complex Organic–Inorganic Interfaces: A Tractable Ab Initio GW Approach

Complex organic–inorganic interfaces are important for device and sensing applications. Charge transfer doping is prevalent in such applications and can affect the interfacial energy level alignments (ELA), which are determined by many-body interactions. We develop an approximate ab initio many-body GW approach that can capture many-body interactions due to interfacial charge transfer. The approach uses significantly less resources than a regular GW calculation but gives excellent agreement with benchmark GW calculations on an F4TCNQ/graphene interface. We find that many-body interactions due to charge transfer screening result in gate-tunable F4TCNQ HOMO–LUMO gaps. We further predict the ELA of a large system of experimental interest—4,4'-bis(dimethylamino)bipyridine (DMAP-OED) on monolayer MoS 2 , where charge transfer screening results in an ~1 eV reduction of the molecular HOMO–LUMO gap. Comparison with a two-dimensional electron gas model reveals the importance of explicitly considering the intraband transitions in determining the charge transfer screening in organic–inorganic interface systems.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

Investigation and application of quantitative relationship between sp energy levels of Bi{sup 3+} ion and host lattice

Information on {sup 1}S{sub 0}-{sup 3}P{sub 1} (A band) and {sup 1}S{sub 0}-{sup 1}P{sub 1} (C band) transition energy of Bi{sup 3+} ion in dozens of different compounds has been gathered and analyzed. With the use of the dielectric theory of the chemical bond for complex crystals, relationships between A and C absorption band and environmental factor h{sub e} were established: E{sub A}=2.972+6.206exp (-h{sub e}/0.551); E{sub C}=3.236+10.924exp (-h{sub e}/0.644). For Bi{sup 3+} doped hosts with known structure and refractive index, it is possible to predict Bi{sup 3+} energy level position with an good accuracy of typically {+-}0.51 eV using the two relationships. Moreover, a direct relationship between A and C band was deduced: E{sub C}=3.236+2.290(E{sub A}-2.972){sup 0.856}. Thus a very simple method to predict C band position was proposed. This work will be of great help to understand spectroscopy of Bi{sup 3+} and will be useful for developing new PDP, LED and mercury-free fluorescent lamp phosphors. - Graphical abstract: This figure shows relationship between positions of A band and C band of Bi{sup 3+} ion and environmental factor h{sub e} of host. It establishes the relation between macroscopical spectroscopy of Bi{sup 3+} ion and microcosmic structure of the hosts. Highlights: Black-Right-Pointing-Pointer Relationships between A, C absorption band and environmental factor h{sub e} were established. Black-Right-Pointing-Pointer A direct relation between A and C band was deduced and an easier method to predict C band was given. Black-Right-Pointing-Pointer Positions of C band of Bi{sup 3+} ion in some compounds were predicted using our formula.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Extended calculations with spectroscopic accuracy: Energy levels and transition properties for the fluorine-like isoelectronic sequence with Z = 24–30

We have performed extensive multiconfiguration Dirac–Hartree–Fock calculations and second-order many-body perturbation calculations for F-like ions with Z = 24–30. Energy levels and transition rates for electric dipole (E1), electric-quadrupole (E2), electric-octupole (E3), magnetic dipole (M1), and magnetic-quadrupole (M2) transitions, as well as radiative lifetimes, are provided for the lowest 200 levels belonging to the 1s{sup 2}2s{sup 2}2p{sup 5}, 1s{sup 2}2s2p{sup 6}, 1s{sup 2}2s{sup 2}2p{sup 4}3l, 1s{sup 2}2s2p{sup 5}3l, 1s{sup 2}2p{sup 6}3l, and 1s{sup 2}2s{sup 2}2p{sup 4}4l configurations of each ion. The results from the two sets of calculations are in excellent agreement. Extensive comparisons are also made with other theoretical results and observed data from the CHIANTI and NIST databases. The present energies and wavelengths are believed to be accurate enough to aid line identifications involving the n = 3 and n = 4 configurations, for which observations are largely missing. The calculated wavelengths and transition data will be useful in the modeling and diagnostics of astrophysical and fusion plasmas.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2019

Interatomic interactions and thermally induced shifts and broadenings of energy levels of atoms in circular Rydberg states

Analytical expressions are obtained for the constants determining the energy of the long-range (at large distances exceeding the LeRoy radius R{sub LR} ≈ 4n{sup 2}) polarisation interaction of the multipole electric moments of two atoms in identical Rydberg states with large principal (n) and maximum orbital (l) and magnetic (m) quantum numbers (|m| = l = n − 1). Asymptotic expansions in powers of n are found for the components of the van der Waals interaction tensor, which determine the dependence of the dispersion energy on the orientation of the interatomic axis. The spontaneous and thermally induced broadenings of the energy levels of circular states are represented analytically as functions of the principal quantum number and temperature. It is found that analytical formulae for the sum of spontaneous and thermally induced line widths in the region of high temperatures and large principal quantum numbers (assuming n{sup 3}k{sub B}T >> 1) do not contain a temperature-independent contribution of the spontaneous part of the broadening. Closed analytical expressions are also obtained for the Farley − Wing function and for the n- and T-dependent corrections to the asymptotic behaviour of the thermally induced shift. (paper)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2015

City-Level Energy Decision Making. Data Use in Energy Planning, Implementation, and Evaluation in U.S. Cities

The Cities-LEAP technical report, City-Level Energy Decision Making: Data Use in Energy Planning, Implementation, and Evaluation in U.S. Cities, explores how a sample of cities incorporates data into making energy-related decisions. This report provides the foundation for forthcoming components of the Cities-LEAP project that will help cities improve energy decision making by mapping specific city energy or climate policies and actions to measurable impacts and results.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

Assisted extraction of the energy level spacings and lever arms in direct current bias measurements of one-dimensional quantum wires, using an image recognition routine

A multiplexer technique is used to individually measure an array of 256 split gates on a single GaAs/AlGaAs heterostructure. This results in the generation of large volumes of data, which requires the development of automated data analysis routines. An algorithm is developed to find the spacing between discrete energy levels, which form due to transverse confinement from the split gate. The lever arm, which relates split gate voltage to energy, is also found from the measured data. This reduces the time spent on the analysis. Comparison with estimates obtained visually shows that the algorithm returns reliable results for subband spacing of split gates measured at 1.4 K. The routine is also used to assess direct current bias spectroscopy measurements at lower temperatures (50 mK). This technique is versatile and can be extended to other types of measurements. For example, it is used to extract the magnetic field at which Zeeman-split 1D subbands cross one another.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2019

Energy levels, weighted oscillator strengths, transition rates, lifetimes, hyperfine structures and isotope shifts of He-like-Sn deduced from the relativistic multiconfiguration Dirac–Hartree–Fock and second-order many-body perturbation theory calculations

We disclose relativistic multiconfiguration Dirac–Hartree–Fock (MCDHF) spectrum calculations for SnXLIX. Energy levels, weighted oscillator strengths, isotope shifts, hyperfine structure and Landé g{sub J} factors are calculated for 127 odd- and even-parity states as well as lifetimes and transition rates between these states. To scrutinize the accuracy of our results, we have implemented parallel calculations using a Flexible Atomic Code (FAC) by introducing the Second-Order Many-Body Perturbation Theory (MBPT) method. Additionally, the Breit interaction and leading quantum electrodynamic effects (QED) are included as perturbations in extensive relativistic configuration interaction (RCI) calculations. We signal that, our calculations for SnXLIX are made for the first time and they provide to date the most accurate and complete atomic data related to this ion.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2018

National-Level Energy Impacts of Cooperative Adaptive Cruise Control (CACC) Systems

This poster highlights a study of the potential national-level energy impact of connected and automated vehicles and technologies (e.g., cooperative adaptive cruise control (CACC), eco-signals, automated mobility districts, etc.) and how varying levels of CACC adoption affect on-road fuel economy for different vehicle powertrains as well as potential changes in vehicle-miles-traveled distributions.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2011

Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon

Energy levels, Auger branching ratios, and radiative rates of the core-excited states of B-like carbon are calculated by the saddle-point variation and saddle-point complex-rotation methods. Relativistic and mass polarization corrections are included using first-order perturbation theory. Calculated Auger channel energies and branching ratios are used to identify high-resolution Auger spectrum in the 300-keV C{sup +}{yields} CH{sub 4} collision experiment. It is found that Auger decay of these five-electron core-excited states gives significant contributions to Auger spectrum in the range of 238-280 eV.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

High resolution spectral analysis of oxygen. IV. Energy levels, partition sums, band constants, RKR potentials, Franck-Condon factors involving the X{sup 3}Σ{sub g}{sup −}, a{sup 1}Δ{sub g} and b{sup 1}Σ{sub g}{sup +} states

We have updated the isotopically invariant Dunham fit of O{sub 2} with newly reported literature transitions to derive (1) the energy levels, partition sums, band-by-band molecular constants, and RKR potentials for the X{sup 3}Σ{sub g}{sup −}, a{sup 1}Δ{sub g}, and b{sup 1}Σ{sub g}{sup +} states of the six O{sub 2} isotopologues: {sup 16}O{sup 16}O, {sup 16}O{sup 17}O, {sup 16}O{sup 18}O, {sup 17}O{sup 17}O, {sup 17}O{sup 18}O, and {sup 18}O{sup 18}O; (2) Franck-Condon factors for their a{sup 1}Δ{sub g}−X{sup 3}Σ{sub g}{sup −}, b{sup 1}Σ{sub g}{sup +}−X{sup 3}Σ{sub g}{sup −}, and a{sup 1}Δ{sub g}−b{sup 1}Σ{sub g}{sup +} band systems. This new spectroscopic parameterization characterizes all known transitions within and between the X{sup 3}Σ{sub g}{sup −}, a{sup 1}Δ{sub g}, and b{sup 1}Σ{sub g}{sup +} states within experimental uncertainty and can be used for accurate predictions of as yet unmeasured transitions. All of these results are necessary to provide a consistent linelist of all transitions which will be reported in a followup paper.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Theoretical level energies and transition data for ion W{sup 28+}

The ab initio quasirelativistic approach was used to derive transition data for Pd-like tungsten W{sup 28+} ion. This approach was developed specifically for the calculation of spectral parameters for highly charged ions. The relativistic effects were taken into account in the Breit–Pauli approximation. The configuration interaction method was applied to include electron correlation effects. The ground configuration 4p{sup 6}4d{sup 10} and the lowest excited 4p{sup 6}4d{sup 9}4f were considered. The calculations for W{sup 28+} were performed with different sets of interacting configurations in order to evaluate reliability and accuracy of produced results. Level energies, radiative lifetimes τ, Landé g-factors were determined for the excited configuration 4p{sup 6}4d{sup 9}4f of W{sup 28+} levels. The radiative transition wavelengths λ and emission transition probabilities A for the electric and magnetic transitions of various multipole order (up to E5 and M4) among the levels of these two configurations were produced. The uncertainties of computed spectroscopic parameters were evaluated.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

SYSTEMATIC CALCULATIONS OF ENERGY LEVELS AND TRANSITION RATES OF C-LIKE IONS WITH Z = 13-36

Based on systematic calculations using a combined relativistic configuration interaction and a many-body perturbation theory (MBPT) approach, we provide a complete and consistent data set for 46 levels belonging to the 2s {sup 2}2p {sup 2}, 2s2p {sup 3}, 2p {sup 4}, 2s {sup 2}2p3s, 2s {sup 2}2p3p, and 2s {sup 2}2p3d configurations in C-like ions with 13 ≤ Z ≤ 36. The data set includes energy levels as well as electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition properties. Extensive comparisons with available observed and calculated results are made and indicate that the present MBPT calculations are highly accurate. The present data set can be used reliably for many purposes, such as the line identification of observed spectra, and modeling and diagnostics of astrophysical and fusion plasmas.

79 ASTRONOMY AND ASTROPHYSICS↗