Fibre-optic delivery of time and frequency to VLBI station

Abstract

The quality of Very Long Baseline Interferometry (VLBI) radio observations predominantly relies on precise and ultra-stable time and frequency (T&F) standards, usually hydrogen masers (HM), maintained locally at each VLBI station. Here, we present an operational solution in which the VLBI observations are routinely carried out without use of a local HM, but using remote synchronization via a stabilized, long-distance fibre-optic link. The T&F reference signals, traceable to international atomic timescale (TAI), are delivered to the VLBI station from a dedicated timekeeping laboratory. Moreover, we describe a proof-of-concept experiment where the VLBI station is synchronized to a remote strontium optical lattice clock during the observation.

arXiv comment8 pages, 8 figures, matches the version published in A&A, section Astronomical instrumentation

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Cited by in corpus (7)

• Achieving the ultimate quantum timing resolution
• SI-traceable frequency dissemination at 1572.06 nm in a stabilized fiber network with ring topology
• Effects of coherence on temporal resolution
• Frequency drift corrected ultra-stable laser through phase-coherent fiber producing a quantum channel
• Optical frequency comb integration in radio telescopes: advancing signal generation and phase calibration
• A High-frequency Geodetic VLBI Experiment for Optical Clock Comparison
• Phase synchronisation system receiver module for the Mid-Frequency Square Kilometre Array