U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: David B. Newell (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 126 - 150 of 150

Towards a Traceable Nanoscale Force Standard

May 1, 2001
Author(s)
Jon R. Pratt, David B. Newell, Edwin R. Williams, Douglas T. Smith, John A. Kramar
The National Institute of Standards and Technology has launched a five-year project to traceably link the International System of Units (SI) to forces between 10 -8N and 10 -2N. In this paper, we give a background and overview of this project, discuss the

Hysteresis and Related Error Mechanisms in the NIST Watt Balance Experiment

February 16, 2001
Author(s)
J. Schwarz, Ruimin Liu, David B. Newell, Richard L. Steiner, Edwin R. Williams, Douglas T. Smith, A Erdemir, J Woodford
The NIST Watt Balance experiment is being completely rebuilt after its 1998 determination of the SI Volt and Planck's constant. That measurement yielded a result with approximately 1 x 10 -7 standard relative uncertainty. Because the goal of the new

SI Traceability of Force at the Nanonewton Level

January 1, 2001
Author(s)
David B. Newell, Jon R. Pratt, John A. Kramar, Douglas T. Smith, L Feeney, Edwin R. Williams
Although nanonewton force measurements are commonplace in industry, no National Measurement Institute supports a link to the International System of Units (SI) below one newton. The National Institute of Standards and Technology has launched a five-year

Reconstruction and Preliminary Tests of the NIST Electronic Kilogram Experiment

May 1, 2000
Author(s)
Richard L. Steiner, David B. Newell, J. Schwarz, Edwin R. Williams, Ruimin Liu
The NIST electronic kilogram experiment is being completely rebuilt into a vaccum chamber within a specially designed laboratory room. Major renovations include reference mass positioning equipment, structural alignment flexures, and a redesigned inductive

Planck Constant Determination from Power Equivalence

April 1, 2000
Author(s)
David B. Newell
Equating mechanical to electrical power links the kilogram, the meter, and the second to the practical realizations of the ohm and the volt derived from the quantum Hall and the Josephson effects, yielding an SI determination of the Planck constant. The

Watt's Up, Doc? The NIST Watt Experiment and the Future of the Kg

March 21, 2000
Author(s)
J. Schwarz, Ruimin Liu, David B. Newell, Richard L. Steiner, Edwin R. Williams
The Nist Watt Balance is an interesting and beautiful experiment housed in the nonmagnetic building behind the reactor. The underlying physical principles of the experiment are very simple: a current in a magnetic gradient will produce a force that is

Reference Standards, Uncertainties, and the Future of the NIST Electronic Kilogram

July 1, 1999
Author(s)
Richard L. Steiner, David B. Newell, J. Schwarz, Edwin R. Williams
The National Institute of Standards and Technology (NIST) watt balance experiment recently made a new determination of Planck's constant with a relative standard uncertainty of 87 x 10 -9 (k = 1), concurrently with an upper limit on the drift rate of the

A Result from the NIST Watt Balance and an Analysis of Uncertainties

April 1, 1999
Author(s)
Richard L. Steiner, David B. Newell, Edwin R. Williams
An improved determination of the ratio of power, measured in terms of the Josephson and quantum Hall effects, and also the meter, kilogram, and second, has been completed. The result is expressed as: W 90/W = 1 + (8187) x 10 -9. This is an order of

The NIST Watt Balance: Recent Results and Future Plans

March 1, 1999
Author(s)
David B. Newell, Richard L. Steiner, Edwin R. Williams
The last remaining SI base unit defined by an artifact is the kilogram. The NIST watt balance has been designed to measure the ratio of mechanical to electrical power, linking the artifact kilogram, the meter, and the second to the practical realizations

The Next Generation of the NIST Watt Balance

August 1, 1998
Author(s)
David B. Newell, Richard L. Steiner, Edwin R. Williams, Alain Picard
Reduction in the total uncertainty of the NIST Watt Balance is limited by the present configuration of the experiment. Most of the major relative uncertainty components arise from the fact that the experiment is performed in air. To reduce the contribution

An Accurate Measurement of Planck's Constant

July 1, 1998
Author(s)
Edwin R. Williams, Richard L. Steiner, David B. Newell
Using a moving coil watt balance, electric power measured in terms of the Josephson and quantum Hall effects is compared with mechanical power measured in terms of the meter, kilogram and second, we find the Planck constant h = 6.62606891(58) x 10 -34 Js

Experimental Noise Sources in the NIST Watt Balance

July 1, 1998
Author(s)
Richard L. Steiner, David B. Newell, Edwin R. Williams
The present NIST Watt Balance has a relative combined standard uncertainty of about 145 nW/W. The final results of this phase of the experiment are presented. Improvements in the Type B (nonstatistical) uncertainty contributions, along with several

Multi-Stage Active Vibration Isolation System

June 1, 1998
Author(s)
S J. Richman, J A. Giaime, David B. Newell, R T. Stebbins, P L. Bender, J E. Faller
The major obstacle to the detection of low-frequency gravitational waves with an earth-based interferometer is seismic noise. The current design of the initial LIGO (Laser Interferometer Gravitational-wave Observatory) receiver, now under construction

The NIST Electronic Kilogram

January 1, 1997
Author(s)
David B. Newell, K Fujii, Andrew Gillespie, P. T. Olsen, Alain Picard, Richard L. Steiner, Gerard N. Stenbakken, Edwin R. Williams

Details of the 1998 Watt Balance Experiment Determining the Planck Constant

Author(s)
Richard L. Steiner, David B. Newell, Edwin R. Williams
The National Institute of Standards and Technology (NIST) watt balance experiment completed a determination of Planck's constant in 1998 with a relative standard uncertainty of 87 x 10-9 (k = 1), concurrently with an upper limit on the drift rate of the SI

The NIST Project for the Electronic Realization of the Kilogram

Author(s)
Richard L. Steiner, David B. Newell, Edwin R. Williams, Ruimin Liu, Pierre Gournay
The project, the Electronic Realization of the Kilogram, has rebuilt the NIST Watt balance, which has been fully operational for nine months. Short-term noise is at an all time low with overnight runs exhibiting standard deviations of parts in 108. Recent

Uncertainty Improvements of the NIST Electronic Kilogram

Author(s)
Richard L. Steiner, Edwin R. Williams, Ruimin Liu, David B. Newell
This paper summarizes the latest uncertainty improvements in the NIST Electronic Kilogram experiment to obtain result of 7 +/- 37 nW/W for the ratio {W 90/W -1} (and the Planck constant), comparable to the NIST 2005 value but with a lower uncertainty. Of