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: Tom Parker (Assoc)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 76 - 100 of 135

A New Technique for Estimating Frequency from GPS Carrier-Phase Time Transfer Data

August 28, 2004
Author(s)
C Hackman, Judah Levine, Tom Parker, Dirk Piester, Juergen Becker
GPS carrier-phase time transfer (GPSCP1T) offers high frequency stability at short averaging times, approaching a fractional frequency stability of 10-15 at averaging times of one day. However, a discontinuity occurs in the time transfer estimates between

Improvements in NIST-F1 and a Resulting Accuracy of df/f = 0.61 * 10 -15

August 23, 2004
Author(s)
Thomas P. Heavner, Steven R. Jefferts, Elizabeth A. Donley, Jon H. Shirley, Thomas E. Parker
Over the last several years we have made many improvements to NIST-F1 (a laser-cooled cesium fountain primary frequency standard) resulting in a reduction in the uncertainty by nearly a factor of 2 in the realization of the SI second at NIST. We recently

Atomic Time

January 1, 2002
Author(s)
Thomas E. Parker, Marc A. Weiss

A U.S. Laser-Cooled Atomic-Clock System for Space

January 1, 2001
Author(s)
Donald Sullivan, Thomas P. Heavner, Leo W. Hollberg, D Meekhof, Thomas E. Parker, William D. Phillips, S L. Rolston, Hugh Robinson, Jon H. Shirley, F L. Walls, Neil Ashby, W Kepstein, L Maleki, D Seidel, R Q. Thompson, S Wu, L Young, R Vessot, E Mattison, A Demarchi

Primary Atomic Frequency Standards at NIST

January 1, 2001
Author(s)
Donald Sullivan, James C. Bergquist, Robert E. Drullinger, Wayne M. Itano, Steven R. Jefferts, D W. Lee, D Meekhof, Thomas E. Parker, F L. Walls, David J. Wineland