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Ronald Colle, Lizbeth Laureano-Perez, Svetlana Nour, Jerome J. LaRosa, Brian E. Zimmerman, Leticia S. Pibida, Denis E. Bergeron
A new natural uranium solution standard has been produced and will be disseminated by the National Institute of Standards and Technology (NIST) as Standard Reference Material 4321d. The standard is certified for the massic activities of 234U, 235U, and
Vladimir I. Azarov, Alexander Kramida, M. Y. Vokhmentsev
The article describes a Java program that can be used in a user]friendly way to visually identify spectral lines observed in complex spectra with theoretically predicted transitions between atomic or molecular energy levels. The program arranges various
Nathan Mahynski, Jeffrey R. Errington, Vincent K. Shen
We derive an approach for extrapolating the free energy landscape of multicomponent systems in the grand canonical ensemble, obtained from flat- histogram Monte Carlo simulations, from one set of temperature and chemical potentials to another. This is
Effective spin-spin interactions between N + 1 qubits enable the determination of the eigenvalue of an arbitrary Pauli product of dimension N with a constant, small number of multi- qubit gates that is independent of N and encodes the eigenvalue in the
Harold W. Hatch, Nathan Mahynski, Marco A. Blanco Medina, Vincent K. Shen, Sally Jiao
Virial coefficients are predicted over a large range of both temperatures and model parameter values (e.g., alchemical transformation) from an individual Mayer-sampling Monte Carlo simulation by statistical mechanical extrapolation with minimal increase in
Daniel D. Hickstein, David R. Carlson, Abijith S. Kowligy, Matt Kirchner, Scott Domingue, Nima Nader, Henry R. Timmers, Alexander J. Lind, Gabriel G. Ycas, Margaret Murnane, Henry Kapteyn, Scott B. Papp, Scott A. Diddams
Optical waveguides made from periodically poled materials provide high confinement of light and enable the generation of new wavelengths via quasi-phase-matching, making them a key platform for nonlinear optics and photonics. However, such devices are not
Roger C. Brown, Nate B. Phillips, Kyle P. Beloy, William F. McGrew, Marco Schioppo, Robert J. Fasano, Gianmaria Milani, Xiaogang Zhang, Nathan M. Hinkley, Holly F. Leopardi, T H. Yoon, Daniele Nicolodi, Tara M. Fortier, Andrew D. Ludlow
Optical clocks benefit from tight atomic confinement enabling extended interrogation times as well as Doppler- and recoil-free operation. However, these benefits come at the cost of frequency shifts that, if not properly controlled, may degrade clock
Vladislav P. Gerginov, Fabio C. Da Silva, David A. Howe
Signal attenuation limits the operating range in wireless communications and location. To solve the reduced range problem, one can use low-frequency signals in combination with magnetic sensing. We propose the use of an optically-pumped magnetometer as a
We develop a relativistic treatment of interference between light reflected from a falling cube retroreflector in the vertical arm of an interferometer, and light in a reference beam in the horizontal arm. Coordinates that are nearly Minkowskian, attached
In the subject paper [1] of the comment, light propagation through an absolute gravimeter was analyzed, including the propagation delay through the falling retroreflector and through the vacuum. The resulting expression for the interference signal applies
The Newtonian Constant of Gravitation G seems to be the fundamental constant that is most difficult to measure accurately. In the past three decades more than a dozen precision measurements were performed. Unfortunately the scatter of the data points is
Samples of Gorilla® glass (Corning®) from several touchscreen mobile phones were prepared and analyzed using phototransferred thermoluminescence (PTTL) in an attempt to retrospectively assess radiation doses absorbed by the glass for potential applications
Xiaochi Liu, V. I. Yudin, A. V. Taichenachev, John Kitching, Elizabeth Donley
A cold-atom coherent population trapping clock can achieve a better long-term frequency stability than similar clocks based on vapor cells, since long interrogation periods are possible without introducing systematic frequency shifts from buffer gases
We report an accurate measurement of the phase noise of a thermally limited electronic oscillator at 300 K. By thermally limited we mean that the white signal-to-noise ratio of the oscillator is at or near the level generated by the thermal noise of the 50
In this critical compilation, all known to us experimental data on the spectrum of neutral carbon were methodically evaluated and supplemented by parametric calculations with Cowan's code. The sources of experimental data vary from laboratory to
Jack F. Douglas, Hao Zhang, Xuhang Tong, Xinyi Wang
We investigate the collective molecular motions and diffusion of water molecules in the mobile interfacial region of the secondary prismatic plane of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and metrologies of
We report precise experimental values of the enthalpy of sublimation (∆H_s) of quenched condensed films of neon (Ne), nitrogen (N2), oxygen (O2), argon (Ar), carbon dioxide (CO2), krypton (Kr), xenon (Xe), and water (H2O) vapor using a single consistent
We present analytical relations for the dark recombination current of a pn+ junction with positively charged columnar grain boundaries in the high defect density regime. We consider two defect state configurations relevant for positively charged grain
The 1998 CODATA recommended values of the fundamental physical constants have been derived by P.J. Mohr and B.N. Taylor of the NIST Physics Laboratory under the auspices of the CODATA (Committee on Data on Science and Technology) Task Group on Fundamental
Roope J. Kokkoniemi, Tuomas Ollikainen, Sakari Saarenpaa, Janne Kokkala, Ceren Dag, Mikko Mottonen, Russell Lake
We introduce a magnetic-flux-tunable phase shifter for propagating microwave photons, based on three equidistant superconducting quantum interference devices (SQUIDs) on a transmission line. We experimentally implement the phase shifter and demonstrate
Configuration interaction (CI) methods are the method of choice for the determination of wave functions for complex atomic systems from which a variety of atomic properties may be computed. When applied to highly ionized atoms where few, if any, energy
Atomic Spectroscopy Results from the NIST EBIT facility since the last Symposium on Atomic Spectra and Oscillator Strengths are briefly reviewed. With the exception of the helium isoelectronic sequence, results generally agree with the predictions of