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Search Publications

NIST Authors in Bold

Displaying 101 - 125 of 2349

Grating magneto-optical traps with complicated level structures

October 25, 2023
Author(s)
Daniel Barker, Peter Elgee, Ananya Sitaram, Eric Norrgard, Nikolai Klimov, Gretchen K. Campbell, Stephen Eckel
We study the forces and optical pumping within grating magneto-optical traps (MOTs) operating on transitions with non-trivial level structure. In contrast to the standard six-beam MOT configuration, rate equation modelling predicts that the asymmetric

Observation of anisotropic superfluid density in an artificial crystal

October 18, 2023
Author(s)
Ian Spielman, Mingshu Zhao, Junhent Tao
We experimentally and theoretically investigate the anisotropic speed of sound of an atomic superfluid (SF) Bose-Einstein condensate in a 1D optical lattice. Because the speed of sound derives from the superfluid density, implying that this density is

Next-Generation Chip-Scale Atomic Clocks

October 16, 2023
Author(s)
John Kitching, Matthew Hummon, William McGehee, Ying-Ju Wang, Susan Schima
We describe work toward the development of next-generation chip-scale atomic clocks, which combine small size, low power consumption and manufacturability with high frequency stability. The use of optical transitions in microfabricated vapor cells improves

Activation loop plasticity and active site coupling in the MAP kinase, ERK2

October 6, 2023
Author(s)
Laurel Pegram, Demian Riccardi, NATALIE AHN
Previous studies of the protein kinase, ERK2, using NMR and hydrogen-exchange measurements have shown changes in dynamics accompanying its activation by phosphorylation. However, knowledge about the conformational motions involved is incomplete. Here, we

Elastic Behavior of Orientation-Correlated Grains in Multiphase Aggregates

October 1, 2023
Author(s)
Thomas Gnaupel-Herold
Diffraction elastic constants (DECs) describe the elastic response of a subset of orientation-correlated grains which share a common lattice vector. DECs reflect the elastic behaviour of the single-crystal constituents through their dependence on grain

Harmonic dependence of thermal magnetic particle imaging

September 22, 2023
Author(s)
Thinh Bui, Mark-Alexander Henn, Weston L. Tew, Megan Catterton, Solomon I. Woods
Advances in instrumentation and tracer materials are still required to enable sensitive and accurate 3D temperature monitoring by magnetic particle imaging. We have developed a magnetic particle imaging instrument to observe temperature variations using

Open-path measurement of stable water isotopologues using mid-infrared dual-comb spectroscopy

September 8, 2023
Author(s)
Daniel Herman, Griffin Mead, Fabrizio Giorgetta, Esther Baumann, Nathan Malarich, Brian Washburn, Nathan R. Newbury, Ian Coddington, Kevin Cossel
We present an open-path mid-infrared dual-comb spectrometer (DCS) capable of precise measurement of the stable water isotopologues H216O and HD16O. This system runs in a remote configuration at a rural test site with high uptime and achieves a precision of

Radiative Decay Rate and Branching Fractions of MgF

September 8, 2023
Author(s)
Eric Norrgard, Catherine Cooksey, Stephen Eckel, Nickolas Pilgram, Kayla Rodriguez, Howard W. Yoon, Yuly Andrea Chamorro Mena, Lukas Pasteka, Anastasia Borschevsky
Here we report measured and calculated values of radiative decay rates and vibrational branching fractions for the A$^2\Pi$ state of MgF. The decay rate measurements use time-correlated single photon counting with roughly 1\,\% total uncertainty. Branching

Quantifying the Effect of Guest Binding on Host Environment

August 29, 2023
Author(s)
Angela Stelson, Zack Fishman, Jacob Pawlik, Gosia Musial, Jim Booth, Chris Long, Kathleen Schwarz, Nate Orloff, Hugh Ryan, Angela Grommet, Jonathan Nitschke, Felix Rizzuto
The environment around a host-guest complex is defined by of intermolecular interactions between solvent molecules and counter ions. These interactions govern both the solubility of these complexes and the rates of reactions confined within them11. Such

Broadband Electromagnetic Properties of Engineered Flexible Absorber Materials

August 23, 2023
Author(s)
Luckshitha Suriyasena Liyanage, Connor Smith, Jacob Pawlik, Sarah Evans, Angela Stelson, Chris Long, Nate Orloff, David Arnold, Jim Booth
Flexible and stretchable materials have attracted significant interest for applications in wearable electronics and bioengineering fields. Recent developments also incorporate embedded microwave circuits, components, and systems with engineered flexible

National Institute of Standards and Technology Environmental Scan 2023: Societal and Technology Landscape to Inform Science and Technology Research

August 23, 2023
Author(s)
Ashley Boggs-Russell, Kerrianne Buchanan, David W. Griffith, Heather Evans, Dimitrios Meritis, Lisa Ng, Anna Sberegaeva, Michelle Stephens
The 2023 National Institute of Standards and Technology Environmental Scan provides an analysis of key external factors that could impact NIST and the fulfillment of its mission in coming years. The analyses were conducted through three separate lenses

Observations and identifications of extreme ultraviolet spectra of Ca-like to Na-like neodymium ions using an electron beam ion trap

August 23, 2023
Author(s)
Yang Yang, Dipti Dipti, Chihiro Suzukic, A. C. Gall, R. Silwal, Samuel Sanders, Joseph N. Tan, Aung S. Naing, Endre Takacs, Yuri Ralchenko
Extreme ultraviolet (EUV) radiation from M-shell Ca-like, Nd40+, through Nalike, Nd49+, highly charged ions have been measured at an electron beam ion trap (EBIT) facility at the National Institute of Standards and Technology. To produce the ionization

Effects of mechanical deformation on dislocation density and phase partitioning in 4130 steel

August 22, 2023
Author(s)
Zack Buck, Matthew Connolly, May Ling Martin, Damian Lauria, Jason Killgore, Peter Bradley, Yan Chen, Ke An, Andrew Slifka
Interrupted tensile tests were performed on an AISI 4130 pressure vessel steel and investigated by neutron diffraction and scanning microscopy techniques. Analysis of the neutron diffraction patterns reveal a partitioning of ferrite and martensite phases
Displaying 101 - 125 of 2349