Matches in DBpedia 2014 for { <http://dbpedia.org/resource/Caesium_standard> ?p ?o. }
Showing items 1 to 27 of
27
with 100 items per page.
- Caesium_standard abstract "A caesium standard or caesium atomic clock is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency. The first caesium clock was built by Louis Essen in 1955 at the National Physical Laboratory in the UK.Caesium clocks are the most accurate commercially produced time and frequency standards, and serve as the primary standard for the definition of the second in SI (the metric system). By definition, radiation produced by the transition between the two hyperfine ground states of caesium (in the absence of external influences such as the Earth's magnetic field) has a frequency of exactly 9,192,631,770 Hz. That value was chosen so that the caesium second equalled, to the limit of human measuring ability in 1960 when it was adopted, the existing standard ephemeris second based on the Earth's orbit around the Sun. Because no other measurement involving time had been as precise, the effect of the change was less than the experimental uncertainty of all existing measurements.".
- Caesium_standard wikiPageID "40858".
- Caesium_standard wikiPageRevisionID "526946747".
- Caesium_standard hasPhotoCollection Caesium_standard.
- Caesium_standard subject Category:Atomic_clocks.
- Caesium_standard subject Category:Caesium.
- Caesium_standard subject Category:Electronics_standards.
- Caesium_standard subject Category:Time.
- Caesium_standard type Artifact100021939.
- Caesium_standard type Clock103046257.
- Caesium_standard type Clocks.
- Caesium_standard type Device103183080.
- Caesium_standard type Instrument103574816.
- Caesium_standard type Instrumentality103575240.
- Caesium_standard type MeasuringInstrument103733925.
- Caesium_standard type Object100002684.
- Caesium_standard type PhysicalEntity100001930.
- Caesium_standard type Timepiece104437953.
- Caesium_standard type Whole100003553.
- Caesium_standard comment "A caesium standard or caesium atomic clock is a primary frequency standard in which electronic transitions between the two hyperfine ground states of caesium-133 atoms are used to control the output frequency. The first caesium clock was built by Louis Essen in 1955 at the National Physical Laboratory in the UK.Caesium clocks are the most accurate commercially produced time and frequency standards, and serve as the primary standard for the definition of the second in SI (the metric system).".
- Caesium_standard label "Caesium standard".
- Caesium_standard sameAs m.0b5yd.
- Caesium_standard sameAs Q5017052.
- Caesium_standard sameAs Q5017052.
- Caesium_standard sameAs Caesium_standard.
- Caesium_standard wasDerivedFrom Caesium_standard?oldid=526946747.
- Caesium_standard isPrimaryTopicOf Caesium_standard.