title: A VLBI experiment using a remote atomic clock via a coherent fibre link.
abstract: 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.
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Clivati
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Ambrosini
authors.affiliation: Rheinische Friedrich-Wilhelms-Universitat Bonn, Institut fur Geodesie und Geoinformation, Bonn, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Artz
authors.affiliation: Rheinische Friedrich-Wilhelms-Universitat Bonn, Institut fur Geodesie und Geoinformation, Bonn, Germany.|Max-Planck-Institute for Radio Astronomy, Bonn, Germany.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Bertarini
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Bortolotti
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Frittelli
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: Levi
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Mura
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Maccaferri
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Nanni
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Monia
authors.initials: M
authors.lastname: Negusini
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Perini
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Roma
authors.affiliation: Istituto Nazionale di Astrofisica, Istituto di Radioastronomia, Bologna, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Stagni
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Zucco
authors.affiliation: Istituto Nazionale di Ricerca Metrologica, INRIM, Strada delle Cacce 91, 10135 Torino, Italy.
authors.forename: Davide
authors.initials: D
authors.lastname: Calonico