A VLBI experiment using a remote atomic clock via a coherent fibre link
Open accessAbstract
We describe a VLBI experiment in which, for the first time, the clock reference is delivered from a National Metrology Institute to a radio telescope using a coherent fibre link 550 km long. The experiment consisted of a 24-hours long geodetic campaign, performed by a network of European telescopes; in one of those (Medicina, Italy) the local clock was alternated with a signal generated from an optical comb slaved to a fibre-disseminated optical signal. The quality of the results obtained with this facility and with the local clock is similar: interferometric fringes were detected throughout the whole 24-hours period and it was possible to obtain a solution whose residuals are comparable to those obtained with the local clock. These results encourage further investigation of the ultimate VLBI performances achievable using fibre dissemination at the highest precision of state-of-the-art atomic clocks.
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The optical link contributes less than 1 × 10^-18 after 1000 s of averaging time.
“In these conditions, the optical link contributes less than 1 × 10 -18 after 1000 s of averaging time 41,83 .”
From Intercontinental comparison of optical atomic clocks through very long baseline interferometry (2021) · cites this paper as [41]
The “Time in VLBI observations” section reports optical-fibre-link stability of 10⁻¹⁴ to 10⁻¹⁵ over a few seconds, but gives no link contribution after 1000 s. Searches for “1000 s,” “10⁻¹⁸,” and averaging-time stability found no passage supporting the claimed threshold. (LLM, conf=0.75)
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References 22 · Cited by 123
Research works printed but not linked: 13
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- Authors
- Clivati, C., Ambrosini, R., Artz, T., Bertarini, A., Bortolotti, C., Frittelli, M., Levi, F., Mura, A., Maccaferri, G., Nanni, M., Negusini, M., Perini, F., Roma, M., Stagni, M., Zucco, M., & Calonico, D.
- Affiliations
- Istituto Nazionale di Ricerca Metrologica (IT)
- Istituto di Radioastronomia di Bologna (IT)
- University of Bonn (DE)
- Corresponding author
- Calonico, Davide
- ORCID
- Venue
- Scientific Reports
- Published
- 2017-02-01
- Volume
- 7
- Issue
- 1
- Pages
- 40992-40992
- ISSN
- 2045-2322 (ISSN-L)
- PMC
- PMC5286532
- OpenAlex
- W2584278356
- Cited by
- 123
- References
- 22
- Citations by year
- 2026: 5 · 2025: 11 · 2024: 10 · 2023: 9 · 2022: 19 · 2021: 15 · 2020: 19 · 2019: 16 · 2018: 12 · 2017: 7
- FWCI
- 7.38
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- Scientific Reports (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- CINECA IRIS Institutional Research Information System (IRIS Istituto Nazionale di Ricerca Metrologica) (submittedVersion, cc-by)
- Funders
- European Commission (HORIZON2020)
- Ministero dell’Istruzione, dell’Università e della Ricerca
- European Metrology Programme for Innovation and Research (15SIB05)
- Topics
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Advanced Frequency and Time Standards
- Physical Sciences › Engineering › Aerospace Engineering › GNSS positioning and interference
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Radio Astronomy Observations and Technology
- Keywords
- very long baseline interferometry, atomic clocks, optical frequency combs, geodetic VLBI
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