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Tom Parker (Assoc)

Publications

A Resilient Architecture for the Realization and Distribution of Coordinated Universal Time to Critical Infrastructure Systems in the United States: Methodologies and Recommendations from the National Institute of Standards and Technology (NIST)

Author(s)
Jeffrey Sherman, Ladan Arissian, Roger Brown, Matthew J. Deutch, Elizabeth Donley, Vladislav Gerginov, Judah Levine, Glenn Nelson, Andrew Novick, Bijunath Patla, Tom Parker, Benjamin Stuhl, Jian Yao, William Yates, Michael A. Lombardi, Victor Zhang, Douglas Sutton
The Time and Frequency Division of the National Institute of Standards and Technology (NIST), an agency of the United States Department of Commerce (DOC), was

Frequency Ratio Measurements with 18-Digit Accuracy Using a Network of Optical Clocks

Author(s)
Kyle Beloy, Martha I. Bodine, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Jean-Daniel Deschenes, Scott Diddams, Robert J. Fasano, Tara Fortier, Youssef Hassan, David Hume, Dhruv Kedar, Colin J. Kennedy, Isaac Kader, Amanda Koepke, David Leibrandt, Holly Leopardi, Andrew Ludlow, Will McGrew, William Milner, Daniele Nicolodi, Eric Oelker, Tom Parker, John M. Robinson, Stefania Romisch, Stefan A. Schaeffer, Jeffrey Sherman, Laura Sinclair, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang
Atomic clocks occupy a unique position in measurement science, exhibiting higher accuracy than any other measurement standard and underpinning six out of seven

Measurement of the 27Al+ and 87Sr absolute optical frequencies

Author(s)
Holly Leopardi, Kyle Beloy, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Scott Diddams, Robert J. Fasano, Youssef S. Hassan, David B. Hume, Dhruv Kedar, Colin J. Kennedy, Isaac H. Khader, David R. Leibrandt, Andrew D. Ludlow, William F. McGrew, William R. Milner, Daniele Nicolodi, Eric Oelker, Thomas E. Parker, John M. Robinson, Stefania Romisch, Jeffrey A. Sherman, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang, Tara M. Fortier
We perform absolute measurement of the 27Al+ single-ion and 87Sr neutral lattice clock frequencies at the National Institute of Standards and Technology and

Optical-Clock-Based Time Scale

Author(s)
Jian Yao, Jeffrey A. Sherman, Tara M. Fortier, Andrew D. Ludlow, Holly Leopardi, Thomas E. Parker, William F. McGrew, Scott A. Diddams, Judah Levine
A time scale is a procedure for accurately and continuously marking the passage of time. It is exemplified by coordinated universal time (UTC), and provides the
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Created August 27, 2019, Updated December 8, 2022