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Displaying 1101 - 1125 of 2503

CRITICALLY EVALUATED SPECTRAL DATA FOR NEUTRAL CARBON (C I)

November 22, 2017
Author(s)
Haris Kunari, Alexander Kramida
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

String-like Collective Motion and Diffusion in the Interfacial Region of Ice

November 20, 2017
Author(s)
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

Flux-tunable phase shifter for microwaves

November 7, 2017
Author(s)
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

High-Performance Coherent Population Trapping Clock Based on Laser-Cooled Atoms

November 2, 2017
Author(s)
Xiaochi Liu, Eugene Ivanov, V. I. Yudin, John Kitching, Elizabeth Donley
Atomic clocks based on laser-cooled atoms are capable of achieving long interrogation periods and hence narrow resonance linewidths because of the very low atom velocities achievable with laser cooling. The long interrogation periods are achieved without

Radiative rates of transitions from the 2s2p3 5Sdeg2 state in neutral carbon

November 1, 2017
Author(s)
Alexander Kramida, Haris Kunari
The measured radiative rates of the 2s22p2 3P1,2 – 2s2p3 5S°2 intercombination transitions in neutral carbon reported in the literature are critically evaluated in comparison with theoretical results. The experimental and theoretical values are compared

Perspectives for a new realization of the pascal by optical methods

October 24, 2017
Author(s)
Jay H. Hendricks, Karl Jousten, Jack A. Stone Jr., Patrick F. Egan, Tom Rubin, Christof Gaiser, Rene Schodel, James A. Fedchak, Jacob E. Ricker, Jens Fluegge, Stephen P. Eckel, Julia K. Scherschligt, Daniel S. Barker, Kevin O. Douglass, Gregory F. Strouse, Uwe Sterr, Waldimir Sabuga
Since the beginning of measurement of pressure in the 17th century, the unit of pressure has been defined by the relationship of force per unit area. The present state of optical technology now offers the possibility of using a thermodynamic definition

UV superconducting nanowire single-photondetectors with high efficiency, low noise, and4 K operating temperature

October 18, 2017
Author(s)
Varun Verma, Adriana Lita, Richard Mirin, Sae Woo Nam, Emma Wollman, Andrew Beyer, Ryan Briggs, Francesco Marsili, Jason Allmaras, Matthew Shaw
For photon-counting applications at ultraviolet wavelengths, there are currently nodetectors that combine high efficiency (> 50%), sub-nanosecond timing resolution, and sub-Hz dark count rates. Superconducting nanowire single-photon detectors (SNSPDs) have

JY1 Time Scale: a New Kalman-Filter Time Scale Designed at NIST

October 17, 2017
Author(s)
Jian Yao, Thomas E. Parker, Judah Levine
We report on a new Kalman-filter Hydrogen-maser time scale (i.e., JY1 time scale) designed at NIST. The JY1 time scale is composed of a few Hydrogen masers and a Cs clock. The Cs clock is used as a reference clock, to ease operations with existing data

All-silicon light-emitting diodes waveguide-integrated with superconducting single-photon detectors

October 2, 2017
Author(s)
Sonia M. Buckley, Jeffrey T. Chiles, Adam N. McCaughan, Galan Moody, Kevin L. Silverman, Martin J. Stevens, Richard P. Mirin, Sae Woo Nam, Jeffrey M. Shainline
An on-chip, silicon-compatible light source has long been pursued for telecommunications, with limited success. However, for integrated systems utilizing superconducting detectors, cryogenic operation is already required. This allows these systems to

Report for Dedicated JPSS VIIRS Ocean Color Calibration/Validation Cruise October 2016

October 2, 2017
Author(s)
Michael Ondrusek, Veronica P. Lance, Menghua Wang, Charles Kovach, Wesley Goode, Alex Gilerson, Sam Ahmed, Ahmed El-Habashi, Robert Foster, Matteo Ottaviani, Joaquim I. Goes, Helga de Rosario Gomes, Kali McKee, Joo Won Kang, Chuanmin Hu, Jennifer Cannizzaro, Shaojie Sun, David English, B. Carol Johnson, Zhongping Lee, Junfang Lin, Nicholas Tufillaro, Ivan Lalovic, Jasmine Nahorniak, Curtiss Davis, Mike Twardowski, Nicole Stockley, Kenneth Voss
The overall aim of the annual National Oceanic and Atmospheric Administration (NOAA) dedicated Joint Polar Satellite System (JPSS) Visible Infrared Imaging Radiometer Suite (VIIRS) ocean color calibration/validation (cal/val) cruises is to support

Molecular Rigidity, Excess Entropy, and Enthalpy-Entropy Compensation in DNA Melting

September 24, 2017
Author(s)
Jack F. Douglas, Fernando Vargas-Lara, Francis W. Starr
Enthalpy-entropy compensation (EEC) is observed in diverse molecular binding processes of vital importance to living systems and manufacturing applications, but this widely occurring phenomenon is not well understood from a molecular physics standpoint. To

Quantum Randomness from Probability Estimation with Classical Side Information

September 20, 2017
Author(s)
Emanuel H. Knill, Yanbao Zhang, Peter L. Bierhorst
We develop a framework for certifying randomness from Bell test trials based on directly estimating the probability of the measurement outcomes with adaptive test supermartingales. The number of trials need not be predetermined, and one can stop performing

Time Information Broadcasting

September 14, 2017
Author(s)
John P. Lowe
The National Institute of Standards and Technology (NIST) operates radio station WWVB which broadcasts the official time of the United States. WWVB is a 60 kHz standard frequency broadcast emanating from Ft. Collins, Colorado since 1965. The broadcast

Non-Uniqueness in Dual-Energy CT with Beam Hardening

September 13, 2017
Author(s)
Zachary H. Levine
Purpose: The goal is to determine whether dual-energy computed tomography (CT) leads to a unique reconstruction into two basis materials. Methods and Materials: The beam hardening equation is simplified to the single voxel case. The simplified equation is
Displaying 1101 - 1125 of 2503
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