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The NIST Ac-dc 2 Difference Project performs leading edge measurement services and research for ac-dc difference measurements and dc voltage metrology. We
Theory is being developed and used to devise methods for preserving and exploiting the quantum behavior of ever-larger systems for metrology, communication, and
NIST provides calibration services for force-measuring instruments by applying known forces, compression, tension or both, to the elastic transducer and
The NIST Mass and Force Group disseminates the unit of mass, the kilogram, to the US measurement system through calibrations of customer weights and weight sets
Every four years, the Committee on Data for Science and Technology (CODATA) issues recommended values of the fundamental physical constants. The values are
NIST is building a cold-atom vacuum sensor (CAVS) that will be able to measure pressures in the ultra-high vacuum (UHV) regime corresponding to pressures less
We investigate collisions of atoms in either micro-Kelvin gasses or in nano-colliders, where two small atomic clouds are made to collide with adjustable energy
The Dynamic Mechanical Metrology Project develops methods to provide accuracy in, and provides calibration services for, acoustic, vibration, acceleration, and
Our country's way of life depends on the electric power distribution system. Keeping the national electric grid in good working order -- and ensuring power is
The NIST Office of Weights and Measures (OWM) will begin work on developing a guideline document assessing methods for establishing traceability to primary SI
This project aims to provide the world's best basis for accurate impedance measurements by tying the U.S. legal system of electrical units to the International
We are involved in efforts to collate data on precision measurements and the theoretical description of these measurements with the aim to improve the values of
Accurate measurements of atomic wavelengths, energy levels, oscillator strengths and isotope and hyperfine structure using diffraction grating spectrographs
The International System of Units (SI) provides definitions of units of measurement that are widely accepted in science and technology and which set measurement
The quantum optics of light interacting with semiconductor-based nanostructures is being studied to extend concepts of entanglement and coherence in atomic
Using single-photon detection and an adaptive measurement strategy, we determine the state of an optical pulse with errors below what is possible with even the
Resistance standards traceable to NIST provide references for measurements of current at levels from 3000 A to below 20 fA and are used to support a wide
The Newtonian constant of gravitation G is one of the most fundamental constants of classical physics. Recent measurements of G are in disagreement, with
As part of a revised SI system of units adopted in 2019, the kilogram was redefined to be realized in terms of Planck's constant. By experimental necessity
The Precision Electro-Mechanical Experiments (PREME) program develops precision electro-mechanical measurements for fundamental traceability of the SI units and