Featured Research

from universities, journals, and other organizations

NIST Atomic Fountain Clock Gets Much Better With Time

Date:
September 26, 2005
Source:
National Institute of Standards and Technology
Summary:
The world's best clock, NIST-F1, has been improved over the past few years and now measures time and frequency more than twice as accurately as it did in 1999 when first used as a national standard, physicists at the National Institute of Standards and Technology (NIST) report. The improved version of NIST-F1 would neither gain nor lose one second in 60 million years, according to a paper published online Sept. 13 by the journal Metrologia.

NIST researchers (left to right) Steven Jefferts, Elizabeth Donley, and Tom Heavner with NIST F1, the world's best clock (as of Sept. 2005). The clock uses a fountain-like movement of cesium atoms to determine the length of the second so accurately that—if it were to run continuously—it would neither lose nor gain one second in 60 million years. ( 05 Geoffrey Wheeler Photography)

The world’s best clock, NIST-F1, has been improved over thepast few years and now measures time and frequency more than twice asaccurately as it did in 1999 when first used as a national standard,physicists at the National Institute of Standards and Technology (NIST)report.

The improved version of NIST-F1 would neither gain norlose one second in 60 million years, according to a paper publishedonline Sept. 13 by the journal Metrologia.* NIST-F1 uses afountain-like movement of cesium atoms to determine the length of thesecond. The clock measures the natural oscillations of the atoms toproduce more than 9 billion "ticks" per second. These results thencontribute to the international group of atomic clocks that define theofficial world time. NIST-F1 has been formally evaluated 15 times since1999; in its record performance, it measured the second with anuncertainty of 0.53 10-15

The improved accuracy isdue largely to three factors, according to Tom Parker, leader of theNIST atomic standards research group. First, better lasers, softwareand other components have made the entire NIST-F1 system much morereliable and able to operate for longer periods of time. Second, theatoms in the cesium vapor are now spread out over a much larger volumeof space, reducing the frequency shifts caused by interactions amongthe atoms. (The formerly round cloud of atoms is now shaped like ashort cigar.) Third, scientists are now better able to control magneticfields within the clock and quantify the corrections needed tocompensate for their effects on the atoms.

Improved time andfrequency standards have many applications. For instance, ultrapreciseclocks can be used to improve synchronization in precision navigationand positioning systems, telecommunications networks, and wireless anddeep-space communications. Better frequency standards can be used toimprove probes of magnetic and gravitational fields for security andmedical applications, and to measure whether “fundamental constants”used in scientific research might be varying over time—a question thathas enormous implications for understanding the origins and ultimatefate of the universe.

###

* T.P. Heavner, S.R. Jefferts, E.A. Donley, J.H. Shirley, T.E.Parker. 2005. NIST-F1: Recent improvements and accuracy evaluations.Metrologia (October 2005). Posted online Sept. 13.


Story Source:

The above story is based on materials provided by National Institute of Standards and Technology. Note: Materials may be edited for content and length.


Cite This Page:

National Institute of Standards and Technology. "NIST Atomic Fountain Clock Gets Much Better With Time." ScienceDaily. ScienceDaily, 26 September 2005. <www.sciencedaily.com/releases/2005/09/050926080117.htm>.
National Institute of Standards and Technology. (2005, September 26). NIST Atomic Fountain Clock Gets Much Better With Time. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2005/09/050926080117.htm
National Institute of Standards and Technology. "NIST Atomic Fountain Clock Gets Much Better With Time." ScienceDaily. www.sciencedaily.com/releases/2005/09/050926080117.htm (accessed September 20, 2014).

Share This



More Matter & Energy News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What This MIT Sensor Could Mean For The Future Of Robotics

What This MIT Sensor Could Mean For The Future Of Robotics

Newsy (Sep. 20, 2014) MIT researchers developed a light-based sensor that gives robots 100 times the sensitivity of a human finger, allowing for "unprecedented dexterity." Video provided by Newsy
Powered by NewsLook.com
MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
New Music With Recycled Instruments at Colombia Fest

New Music With Recycled Instruments at Colombia Fest

AFP (Sep. 19, 2014) Jars, bottles, caps and even a pizza box, recovered from the trash, were the elements used by four musical groups at the "RSFEST2014 Sonorities Recycling Festival", in Colombian city of Cali. Duration: 00:49 Video provided by AFP
Powered by NewsLook.com
Virtual Reality Headsets Unveiled at Tokyo Game Show

Virtual Reality Headsets Unveiled at Tokyo Game Show

AFP (Sep. 18, 2014) Several companies unveiled virtual reality headsets at the Tokyo Game Show, Asia's largest digital entertainment exhibition. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins