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| Titel |
Using a transportable optical clock for chronometric levelling |
| VerfasserIn |
Stefan Vogt, Jacopo Grotti, Silvio Koller, Sebastian Häfner, Sofia Herbers, Ali Al-Masoudi, Gesine Grosche, Heiner Denker, Uwe Sterr, Christian Lisdat |
| Konferenz |
EGU General Assembly 2016
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 18 (2016) |
| Datensatznummer |
250135221
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| Publikation (Nr.) |
 EGU/EGU2016-16061.pdf |
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| Zusammenfassung |
| With their supreme accuracy and precision, optical clocks and new methods of long distance
frequency transfer can be used to determine height differences by measuring the gravitational
red shift between two clocks. We are developing transportable optical clocks and optical
fibre-based means for clock comparisons that can bridge distances of hundredths of
kilometres without accumulation of measurement errors. In this talk, we will focus on the
transportable strontium lattice clock we are developing and its first evaluation. Presently, we
achieve a fractional frequency instability of 3 × 10−17 after 1000 s averaging time, which is
equivalent to a height resolution of 30 cm. The first uncertainty evaluation of the system
yielded 9 × 10−17. We expect rapid improvements to an uncertainty of few parts in
10−17.
This clock will be connected via stabilized optical fibre links with other, stationary frequency
standards. The measured red shifts will be compared with the ones calculated from potential
differences derived with state of the art geodetic data and models. We will discuss the status
of measurements of geodetic relevance with optical clocks and give an outlook on our next
steps.
This work is supported by QUEST, DFG (RTG 1729, CRC 1128), EU-FP7 (FACT) and
EMRP (ITOC). The EMRP is jointly funded by the EMRP participating countries within
EURAMET and the European Union. |
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