Claudio Bortolotti

TL;DR: An 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, encouraging further investigation of the ultimate VLBI performances achievable using fibre dissemination at the highest precision of state-of-the-art atomic clocks.

TL;DR: In the period 2012 June-2013 October, the Sardinia Radio Telescope (SRT) went through the technical commissioning phase as discussed by the authors, which involved three first-light receivers, ranging in frequency between 300MHz and 26GHz, connected to a Total Power back-end.

TL;DR: This work disseminates a coherent optical frequency signal to two distant radio telescopes using a 1739-km-long fiber, confirming that the proposed approach is feasible and configures as a novel tool for studying the role of clocks, troposphere, and systematic effects in the ultimate VLBI resolution.

TL;DR: A coherent fiber link for application in very long baseline interferometry (VLBI) for radio astronomy and geodesy is realized and the possibility of replacing the local hydrogen masers at the VLBI sites with optically-synthesized RF signals is opened.

TL;DR: In this paper, very long baseline interferometry (VLBI) is used to compare two optical clocks located in Japan and Italy through the observation of extragalactic radio sources.