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Standards

Reference instruments

News and Updates

Events

Blog Posts

Title card reads "A Scientific Christmas Tale" with the NIST logo in a wreath and flashing holiday lights.

A Scientific Christmas Tale

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An antique clock showing a few minutes before 12 is topped with a party hat, and colorful streamers hang in the background.

Auld Lang ‘Time’: One of the Country’s Timekeepers Makes Sure We Ring in The New Year at Just the Right Second

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A researcher wearing safety glasses reaches into a box of circuitry and other equipment, which emits a green glow.

Think You Know What a Second Is? It Will Likely Change in the Next Decade.

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Projects and Programs

beam box

The Photoforce Project

Ongoing
Traditional power meters measure the power of a laser beam by absorbing its energy. Radiation pressure (photon momentum) permits the measurement of a beam’s power by “absorbing” its momentum and reflecting its energy. Light reflecting from a mirror causes a force that is proportional to its optical

Precursor Material Qualification

Completed
To develop, utilize, and analyze methods of characterizing the precursor materials in additive manufacturing in both virgin and recycled states with the goal of advancing measurement science to benefit the AM community. The components of principal interest will include the rheological, size

Sensing and Imaging of concealed objects

Ongoing
Threats to personal and collective safety abound in our society. The Security Technologies Group (STG) performs research to advance the technology and measurement science of security imaging and sensing. This work includes the establishment of test and evaluation tools, reference test beds, test

Publications

Feature Description for Assessing Autonomous Vehicle Performance

Author(s)
Edward Griffor, Hadhoum Hajjaj, Thoshitha Gamage, Thomas Roth, Wenqi Guo
This technical report presents a structured methodology for describing and assessing auto-mated vehicle (AV) features, with a focus on ensuring consistent and

Single-cryostat integration of the quantum anomalous Hall and Josephson effects

Author(s)
Jason Underwood, Linsey Rodenbach, Ngoc Thanh Mai Tran, Alireza Panna, Zachary Barcikowski, Molly Andersen, Peng Zhang, Lixuan Tai, Randolph Elmquist, Dean Jarrett, David Goldhaber-Gordon, David Newell, Albert Rigosi
By directly integrating a quantum anomalous Hall resistor (QAHR) and a programmable Josephson voltage standard (PJVS) into a single cryostat, we have

Tools and Instruments

Large Aperture Scanner

Large Aperture Scanner

The Large Aperture Scanner (LAS) scans a radar transceiver over a 5 meter by 20 meter aperture. Image reconstruction techniques enable a three-dimensional
Reference Ballistic Chronograph Figure 1

Reference Ballistic Chronograph

The NIST-developed reference ballistic chronograph (RBC) provides repeatable measurements of the speed of a bullet that will impact a test article, such as