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Francis J. Lovas, Brett A. McGuire, P. B. Carroll, Ryan A. Loomis, Geoffery A. Blake, Jan M. Hollis, Phillip R. Jewell, Anthony J. Remijan
Pety et al. (2012) recently reported the detection and assignment of l-C3H+ in the Horsehead nebula. Here, we expand that analysis to include the J = 1 - 0 and J = 2 - 1 transitions of l-C3H+ observed in absorption towards Sgr B2(N) in data from the
This report provides results and recommendations from the validation testing for the different source configurations and radiation fields produced by special nuclear materials (SNMs) and depleted uranium (DU) listed within the Technical Capability Standard
David L. Miller, Mark W. Keller, Justin Shaw, Katherine P. Rice, Robert Keller, Kyle M. Diederichsen
Single crystal metal films on insulating substrates are attractive for microelectronics and other applications, but they are difficult to achieve on macroscopic length scales. The conventional approach to obtaining such films is epitaxial growth at high
John J. Bollinger, Mauritz van den Worm, Rytis Paskauskas, Brian C. Sawyer, Michael Kastner
When a physical system is coupled to a heat bath, one expects to observe thermalization to an equilibrium state whose temperature is determined by the bath properties. For an isolated many-body system, i.e. in the absence of a heat bath, the situation is
Elizabeth A. Donley, Francois-Xavier R. Esnault, Eric M. Blanshan, John E. Kitching
A compact cold-atom clock based on coherent population trapping (CPT) is being developed. Long-term goals for the clock include achieving a fractional frequency accuracy of 1x10 -13 in a package of less than 10 cm 3 in volume. Here we present an overview
Although the effects of solar and lunar gravitational potentials on the frequencies of orbiting GPS clocks are actually negligible, a naive calculation appears to show that such effects are significant, depending on whether the SV clock is between the
P. Rynkun, P. Jonsson, G. Gaigalas, Charlotte F. Fischer
Energies, E1, M1, E2, M2 transition rates, weighted oscillator strengths, and lifetimes from relativistic con figuration interaction calculations are reported for the states of the (1s2)2s22p3; 2s2p4, and 2p5 con figurations in all nitrogen-like ions
Scott B. Papp, Pascal P. Del'Haye, Scott A. Diddams
We have investigated parametric seeding of a microresonator frequency comb (microcomb) by way of a pump laser with two intensity modulation sidebands. We show that the pump-sideband spacing is precisely replicated throughout the microcomb's optical
GPS disciplined oscillators (GPSDOs) are commonly used as references for frequency calibrations. Over long intervals, a GPSDO is an inherently accurate source of frequency because it is continuously adjusted to agree with the Coordinated Universal Time
Elizabeth A. Goldschmidt, Fabrizio Piacentini, I. Ruo Berchera, Sergey V. Polyakov, Silke Peters, Stefan Kuck, Giorgio Brida, Ivo P. Degiovanni, Alan L. Migdall, Marco Genovese
Knowing the underlying number and structure of occupied modes of a light field plays a crucial role in minimizing loss and decoherence of quantum information. Typically, full characterization of the mode structure involves a series of several separate
This is a written version of the lecture I presented in connection with the Nobel Prize ceremonies in December 2012. The paper briefly summarizes experiments on quantum state manipulaiton and measurement in the context of trapped atomic ions. The focus of
O. Marchuk, Yuri Ralchenko, David R. Schultz, W. Biel, T. Schlummer, TEXTOR Team
Injection of high energy atoms into a confined plasma volume is an established diagnostic technique in fusion research. This method strongly depends on the quality of atomic data for charge exchange spectroscopy (CXRS), motional Stark effect (MSE) and beam
Gillian Nave, Craig J. Sansonetti, J C. Pickering, Matthew Ruffoni, Anne P. Thorne, Florence Liggins
The joint project between NIST and Imperial College London to measure spectra of singly-ionized iron-group elements using Fourier transform and high-resolution grating spectroscopy is described.
Reactor antineutrino experiments have the ability to search for neutrino oscillations independent of reactor flux predictions using a relative measurement of the neutrino flux and spectrum across a range of baselines. The range of accessible oscillation
Scott B. Papp, Pascal P. Del'Haye, Scott A. Diddams
Robust control and stabilization of optical frequency combs enables an extraordinary range of scientific and technological applications, including frequency metrology at extreme levels of precision, novel spectroscopy of quantum gases and of molecules from
Ting Rei Tan, John P. Gaebler, Ryan S. Bowler, Yiheng Lin, John D. Jost, Dietrich G. Leibfried, David J. Wineland
We demonstrate a trapped ion entangling gate scheme proposed by Bermudez et~al [Phys. Rev. A 85, 040302 (2012)]. Simultaneous excitation of a strong carrier and a single sideband transition enables deterministic creation of entangled states. The method
Yuri Ralchenko, H.-K. Chung, S Hansen, C. Bowen, C. J. Fontes
We present the main results of the 7th Non-Local Thermodynamic Equilibrium Code Comparison Workshop held in December 2011 in Vienna, Austria. More than twenty researchers from nine countries, who actively work on development of collisional-radiative codes
Several new generation transfer- and working-standard illuminance meters and tristimulus colorimeters have been developed at the National Institute of Standards and Technology (NIST) to measure all kinds of light sources with low uncertainty. The spectral
Francisco E. Becerra Chavez, Jingyun Fan, Alan L. Migdall
Generalized quantum measurements can perform perfect discrimination of nonorthogonal states by allowing for inconclusive results, task which is impossible performing only measurements with definite outcomes. We demonstrate the realization of generalized
Pascal P. Del'Haye, Scott B. Papp, Scott A. Diddams
Optical whispering-gallery microresonators are useful tools in microphotonics, and non-linear optics at very low threshold powers. Here, we present details about the fabrication of ultra-high-Q whispering-gallery-mode (WGM) resonators made by CO2-laser
We apply the classical over-the-barrier model (COB) to charge transfer between highly charged ions (HCIs)and targets consisting of thin dielectric films on metals. Distances for the onset of classically allowed above surface electron capture are obtained
Robert D. Horansky, Joel N. Ullom, Michael W. Rabin
There is currently significant interest in using superconducting detectors for measurement of ion kinetic energies. Unprecedented resolution is possible with an order of magnitude improvement over semiconductors. Superconducting detectors are now able to
Network synchronization or timing, as it is sometimes called, has always been an important subject since the advent of digital switching and transmission based around Time Division Multiplexing (TDM) technology. Synchronization is a fundamental foundation
Franklyn J. Quinlan, Tara M. Fortier, Haifeng (. Jiang, Scott A. Diddams
We present a frequency domain model of shot noise in the photodetection of ultrashort optical pulse trains using a time-varying analysis. Shot noise-limited photocurrent power spectral densities, signal-to-noise expressions, and shot noise spectral
Behrang H. Hamadani, John F. Roller, Kounavis Panagiotis, Nikolai B. Zhitenev, David J. Gundlach
We have used the technique of photocurrent modulated spectroscopy to investigate the dynamic response of charge carrier transport in thin film CdTe/CdS solar cells as a function of light bias and temperature over a broad excitation frequency range. The