cesium atomic clocks
E116184
Cesium atomic clocks are ultra-precise timekeeping devices that use the microwave frequency of cesium atoms’ electron transitions to define and maintain the international standard for the second.
All labels observed (5)
| Label | Occurrences |
|---|---|
| NIST-F1 | 1 |
| NIST-F1 cesium fountain clock | 1 |
| NIST-F2 cesium fountain clock | 1 |
| cesium atomic clocks canonical | 1 |
| cesium fountain clock | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T982966 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: cesium atomic clocks Context triple: [International Atomic Time, basedOn, cesium atomic clocks]
-
A.
International Atomic Time
International Atomic Time is a high-precision time standard based on the combined output of atomic clocks worldwide, serving as the fundamental reference for modern civil and scientific timekeeping.
-
B.
Astronomical Clock
The Astronomical Clock in Prague is a medieval timepiece and astronomical instrument famous for its intricate mechanical design and hourly animated figures, making it one of the city’s most iconic landmarks.
-
C.
Einstein synchronization convention
The Einstein synchronization convention is a method in special relativity for synchronizing distant clocks using light signals, forming the standard basis for defining simultaneity in inertial frames.
-
D.
Deep Space Network
The Deep Space Network is NASA’s global system of large radio antennas used to track, communicate with, and receive data from distant spacecraft throughout the solar system and beyond.
-
E.
MICROSCOPE satellite mission
The MICROSCOPE satellite mission was a French-led space experiment designed to test the validity of Einstein’s equivalence principle with unprecedented precision by comparing the free fall of different materials in orbit.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: cesium atomic clocks Target entity description: Cesium atomic clocks are ultra-precise timekeeping devices that use the microwave frequency of cesium atoms’ electron transitions to define and maintain the international standard for the second.
-
A.
International Atomic Time
International Atomic Time is a high-precision time standard based on the combined output of atomic clocks worldwide, serving as the fundamental reference for modern civil and scientific timekeeping.
-
B.
Astronomical Clock
The Astronomical Clock in Prague is a medieval timepiece and astronomical instrument famous for its intricate mechanical design and hourly animated figures, making it one of the city’s most iconic landmarks.
-
C.
Einstein synchronization convention
The Einstein synchronization convention is a method in special relativity for synchronizing distant clocks using light signals, forming the standard basis for defining simultaneity in inertial frames.
-
D.
Deep Space Network
The Deep Space Network is NASA’s global system of large radio antennas used to track, communicate with, and receive data from distant spacecraft throughout the solar system and beyond.
-
E.
MICROSCOPE satellite mission
The MICROSCOPE satellite mission was a French-led space experiment designed to test the validity of Einstein’s equivalence principle with unprecedented precision by comparing the free fall of different materials in orbit.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
atomic clock
ⓘ
timekeeping device ⓘ |
| associatedWithOrganization |
International Bureau of Weights and Measures
ⓘ
surface form:
Bureau International des Poids et Mesures
National Institute of Standards and Technology ⓘ National Physical Laboratory ⓘ
surface form:
National Physical Laboratory (UK)
|
| basedOn | hyperfine transition of cesium-133 ground state ⓘ |
| comparedWith | optical atomic clocks ⓘ |
| controlledBy | atomic transition frequency ⓘ |
| defines | SI second ⓘ |
| developedFor | high-precision time standards ⓘ |
| enables | definition of the SI second since 1967 ⓘ |
| firstRealizedIn | 1950s ⓘ |
| hasAccuracy | on the order of 10^-16 relative uncertainty for primary standards ⓘ |
| hasComponent |
cesium beam tube
ⓘ
detector for atomic state ⓘ feedback control system ⓘ frequency synthesizer ⓘ magnetic shielding ⓘ microwave cavity ⓘ quartz oscillator ⓘ vacuum system ⓘ |
| hasLimitation | lower frequency than optical clocks ⓘ |
| hasProperty |
long-term frequency stability
ⓘ
low drift over time ⓘ |
| hasVariant |
cesium beam clock
ⓘ
cesium atomic clocks self-linksurface differs ⓘ
surface form:
cesium fountain clock
space-qualified cesium clock ⓘ |
| maintains | international standard for the second ⓘ |
| measurementPrinciple | resonant interaction of microwaves with cesium atoms ⓘ |
| operatesAtFrequency | 9,192,631,770 hertz ⓘ |
| operatesIn | microwave region of the electromagnetic spectrum ⓘ |
| requires |
stable magnetic field
ⓘ
temperature control ⓘ ultra-high vacuum ⓘ |
| stabilizes | microwave oscillator frequency ⓘ |
| standardizedBy | International Committee for Weights and Measures ⓘ |
| usedFor |
fundamental physics experiments
ⓘ
global navigation satellite systems timing ⓘ international timekeeping ⓘ metrology ⓘ realization of Coordinated Universal Time ⓘ realization of International Atomic Time ⓘ telecommunications synchronization ⓘ |
| usedIn |
ground-based timing laboratories
ⓘ
satellite systems ⓘ time distribution networks ⓘ |
| uses |
cesium atoms
ⓘ
microwave frequency transitions of cesium atoms ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: cesium atomic clocks Description of subject: Cesium atomic clocks are ultra-precise timekeeping devices that use the microwave frequency of cesium atoms’ electron transitions to define and maintain the international standard for the second.
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
NIST-F1 cesium fountain clock
this entity surface form:
NIST-F2 cesium fountain clock
this entity surface form:
cesium fountain clock
this entity surface form:
NIST-F1