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Search Publications by: Gordon A. Shaw (Fed)

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Displaying 1 - 25 of 103

Direct Realization of the Optical Watt from Planck's Constant

October 28, 2024
Author(s)
Brian Simonds, Kyle Rogers, Sven Schulze, David Newell, Gordon Shaw, Paul A. Williams
A primary force standard is implemented to directly realize Planck's constant to the optical Watt by means of radiation pressure at the kilowatt level. The high amplification laser-pressure optic, or HALO, is a multiple reflection radiation pressure

High-Power Radiation-Pressure-based Laser Metrology Using an Electrostatic Force Balance

September 11, 2023
Author(s)
Brian Simonds, Kyle Rogers, Sven Schulze, David Newell, Gordon Shaw, John Lehman, Paul A. Williams
A primary standard electrostatic force balance has been integrated into a multiple-reflection radiation pressure-based laser power meter capable of measuring kilowatts of optical power. We present optical power data at 0.1 kW, 1 kW, 2 kW, and 5 kW with the

Gravimetric deposition of microliter drops with radiometric confirmation

September 9, 2023
Author(s)
Denis E. Bergeron, Richard Essex, Svetlana Nour, Gordon A. Shaw, R. Michael Verkouteren, Ryan P. Fitzgerald
A manual gravimetric dispensing technique is demonstrated using a micropipettor modified for use with removeable microcapillaries. Liquid scintillation sources were prepared from a well-characterized 241Am reference solution, providing a radiometric check

Isotope Dilution Mass Spectrometry as an Independent Assessment for Mass Measurements of Milligram Quantities of Aqueous Solution

January 1, 2023
Author(s)
Richard Essex, Jacqueline L. Mann, Denis E. Bergeron, Ryan P. Fitzgerald, Svetlana Nour, Gordon A. Shaw, R. Michael Verkouteren
Isotope dilution mass spectrometry was used to independently assess the accuracy of mass measurement methods developed to quantitatively dispense milligram quantities of aqueous solution. Solutions of isotopically enriched 158Gd and enriched 155Gd were

Radiation Pressure-based Laser Metrology Implementing an Electrostatic Force Balance

December 12, 2022
Author(s)
Brian Simonds, Kyle Rogers, Sven Schulze, David Newell, Gordon Shaw, Paul A. Williams, John Lehman
A primary standard force sensor and laser power meter are combined to achieve laser power traceability to Planck's constant by means of radiation pressure. We assess the statistical uncertainty for measurements of 1 kW, 2 kW, and 5 kW using an

Proceedings of EUSPEN 2022

October 26, 2022
Author(s)
Sven Schulze, Kumar Arumugam, Rene Theska, Gordon A. Shaw
The 2019 redefinition of the kilogram in the International System of Units (SI) connects the unit of mass with Planck's constant (h) through electrical metrology by means of precision balances. This not only changes the way the mass is defined, but also

MILLIGRAM MASS METROLOGY FOR QUANTITATIVE DEPOSITION OF LIQUID SAMPLES

May 22, 2022
Author(s)
Gordon A. Shaw
Quantitative dispensing of liquids by mass becomes increasingly difficult as sample volume decreases. Whereas milliliter quantities of liquid can be directly weighed as dispensed on an analytical balance or using pycnometer methods, microliter samples are

Toward a New Primary Standardization of Radionuclide Massic Activity Using Microcalorimetry and Quantitative Milligram-Scale Samples

February 24, 2022
Author(s)
Ryan P. Fitzgerald, Bradley Alpert, Dan Becker, Denis E. Bergeron, Richard Essex, Kelsey Morgan, Svetlana Nour, Galen O'Neil, Dan Schmidt, Gordon A. Shaw, Daniel Swetz, R. Michael Verkouteren, Daikang Yan
We present a new paradigm for the primary standardization of radionuclide activity per mass of solution (Bq/g). Two key enabling capabilities are 4π decay-energy spectrometry using chip-scale sub-Kelvin microcalorimeters and direct realization of mass by

Comparison of electrostatic and photon pressure force references at the nanonewton level

May 3, 2021
Author(s)
Gordon Shaw, John A. Kramar, Paul Williams, Matthew Spidell, Richard Mirin, Julian Stirling
This work describes a comparison between nanonewton force references derived from an electrostatic force balance and photon pressure force from calibrated laser optical power in the 1 watt range. The NIST Electrostatic Force Balance (EFB) is used to

Scaling of Mass and Force Using Electrical Metrology

May 3, 2021
Author(s)
Gordon Shaw
The impending redefinition of the International System of Units (SI) allows realization of the kilogram using electrical metrology. It can be shown that electrical metrology can also be used to scale mass using electrostatic forces. An approach to mass

Design of an electrostatic balance to measure optical power of 100 kW

February 19, 2021
Author(s)
Lorenz Keck, Gordon A. Shaw, Renee Theska, Stephan Schlamminger
To accommodate the need for increased portability and accuracy in laser power measurement instrumentation above 100 Watt at the National Institute of Standards and Technology (NIST), a new instrument is required. This instrument is intended to create a new

Simplified kilogram traceability for photon momentum radiometers

October 1, 2020
Author(s)
Kyle A. Rogers, Paul A. Williams, Gordon A. Shaw, John H. Lehman
High power laser applications in areas such as laser processing of materials can require an accurately measured laser power. Radiation pressure-based laser power measurement has been proven as a practical method for quantifying these high-power levels in

Using Radiation Pressure to Develop a Radio-Frequency Power Measurement Technique Traceable to the Redefined SI

October 15, 2018
Author(s)
Christopher L. Holloway, Matthew T. Simons, David R. Novotny, John H. Lehman, Paul A. Williams, Gordon A. Shaw
We discuss a power measurement technique traceable to the International System of Units based on radiation pressure (or radiation force) carried by an electromagnetic wave. A measurement of radiation pressure offers the possibility for a power measurement