Geodetic Survey of NIST, JILA, University of Colorado, and Table Mountain Laboratories

Details

• Personal Author:
  van Westrum, Derek ; Ahlgren, Kevin
• Corporate Authors:
  National Geodetic Survey (U.S.)
• NOAA Program & Office:
  NOS (National Ocean Service) ; NGS (Office of National Geodetic Survey)
• Description:
  Einstein’s theory of general relativity indicates that when any clock is operated at a location “higher” than another (“up” is measured away from the mass that generates the local gravity field) it will be observed to run faster. That is, it will appear to “tick” at a higher frequency to those observers “below.” In our everyday experience, this effect is unnoticeable, but groups at the National Institute for Standards and Technology (NIST) and JILA at the University of Colorado in Boulder, are developing atomic clocks (so-called “optical” clocks and “optical lattice” clocks) with accuracies approaching a few parts in 1020. At this level, changes in a clock’s height of even a few millimeters will cause a noticeable difference in its output frequency and must be accounted for.
• Content Notes:
  Supersedes NOAA NOS NGS Technical Memoranda 73 and 77 respectively
• Keywords:
  Atomic Clocks Geodesy Atomic Clocks
• Series:
  NOAA technical memorandum NOS NGS   99
• DOI:
  https://doi.org/10.25923/8s2t-kh22
• Format:
  pdf
• Document Type:
  Technical Memorandum
• Place as Subject:
  United States
• License:
  https://creativecommons.org/publicdomain/zero/1.0/
• Rights Information:
  CC0 Public Domain
• Compliance:
  Submitted
• Main Document Checksum:
  urn:sha-512:f907622c980f8d7dedf3b2785c7ecfe0841e861f2197285e087545d852be2951f4505e96bfa1571d6eb5363569105336cb74bfcb8d1541512d921e251ea27a48
• Download URL:
  https://repository.library.noaa.gov/view/noaa/70289/noaa_70289_DS1.pdf
• File Type:
  [PDF - 2.78 MB ]