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The Time and Frequency Bulletin provides information on performance of time scales and a variety of broadcasts (and related information) to users of the NIST services.
Angela Stelson, Aaron Hagerstrom, Jeffrey Jargon, Chris Long
Scattering (S-) parameters are fundamental to numerous microwave quantities including antenna factors, microwave power, and phase. The uncertainty in S-parameter measurements is influenced by the test setup, including instrument noise, drift, position of
A InP-based mode-locked laser photonic integrated circuit with a repetition rate of 10 GHz is optically synchronized to a SiN microresonator-based dissipative Kerr soliton with a rep- etition rate of 305 GHz. The synchronization is achieved through
Csilla Szabo-Foster, James Cline, Albert Henins, Lawrence T. Hudson, Marcus Mendenhall
The NIST Vacuum Double-Crystal Spectrometer (VDCS) has been modernized and is now capable of recording reference-free wavelength-dispersive spectra in the 2 keV to 12 keV x-ray energy range. The VDCS employs crystals in which the lattice spacings are
Turbulent flow around an axisymmetric hill at Reynolds number Re H ∼ 1.3 × 10 5 with respect to the hill height is studied using resolved large-eddy simulations (LES). The purpose of the paper is to examine the effect of turbulence in the inflow boundary
Alexandros Chremos, Ferenc Horkay, Jack F. Douglas
We propose an approach to generate a wide range of randomly branched polymeric structures to gain insights into the structure of the assemblies to gain general insights into how polymer topology encodes configurational structure in solution. Our work is
Noah Lupu-Gladstein, Y. Batuhan Yilmaz, David Arvidsson-Shukur, Aharon Brodutch, Arthur Pang, Aephraim Steinberg, Nicole Halpern
Operator noncommutation, a hallmark of quantum theory, limits measurement precision, according to uncertainty principles. Wielded correctly, though, noncommutation can boost precision. A recent foundational result relates a metrological advantage with
Constantinos Makrides, Daniel Barker, James A. Fedchak, Julia Scherschligt, Stephen Eckel, Eite Tiesinga
We have found an error in the computation of the thermally-averaged total elastic rate coefficient for the collision of a room-temperature helium atom with an ultra-cold lithium atom presented. We omitted the factor $2/\sqrt\pi}$ in the normalization over
We report new experimental hyperfine structure constants of levels in neutral and singly ionized Scandium (Sc I & Sc II). We observed spectra of Sc-Ar and Sc-Ne hollow cathode discharges in the region 185 nm - 3500 nm (54,055 cm-1 - 2857 cm-1) using
Demian Riccardi, Zachary Trautt, Ala Bazyleva, Eugene Paulechka, Vladimir Diky, Joe W. Magee, Andrei F. Kazakov, Scott Townsend, Chris Muzny
The ThermoML archive is a subset of Thermodynamics Research Center (TRC) data holdings corresponding to cooperation between NIST TRC and five journals: Journal of Chemical Engineering and Data (ISSN: 0021-9568), The Journal of Chemical Thermodynamics (ISSN