Detection of the Gravitational Redshift of the Cesium Frequency Standard at CRL
Abstract
We have detected the gravitational redshift of a Cs frequency standard that has been transported from CRL Tokyo headquarters, at an altitude of 80 m, to Mt. Ohtakadoya LF standard frequency station, located at an altitude of 794 m, about 250 km far from the CRL Tokyo headquarters. In the Mt. Ohtakadoya LF station, three Cs clocks are equipped to be the references of standard frequency radio signal emission, and they are linked with UTC(CRL) by the GPS common-view time transfer. By using this link, we can compare the frequency of any standards in CRL Tokyo and the Mt. Ohtakadoya LF station with UTC(CRL). An HPS071A Cs frequency standard with a normal tube has been transported by car from the CRL Tokyo headquarters to the LF station on 27 April 2000. After the transport, we observed that the frequency of the Cs standard became higher by about 4.6 x 10(exp -14). According to General Theory of Relativity, a 700-m altitude difference will cause a 7.8 x 10(exp -14) frequency difference. Considering the stability of the Cs standard and the accuracy of time transfer, the observed frequency shift shows an agreement with the theoretically predicted gravitational redshift.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 2000
- Accession Number
- ADA485918
Entities
People
- Mizuhiko Hosokawa
- Noboru Kotake ;kuniyasu Imamura
- Noriyuki Kurihara