Time and Frequency Activities at the  U.S. Naval Observatory

<table>Performance of rubidium fountain against a USNO maser mean, as measured by the
total deviation statistic.  The straight
line segment is a fit to the inverse square-root curve expected for white
frequency noise.</table>

International Journal of Navigation and Observation

fig3

Figure 3

Figure 3: Time and Frequency Activities at the  U.S. Naval Observatory 