Common-clock very long baseline interferometry using a coherent optical fiber link
Autori: Clivati C., Aiello R., Bianco G., Bortolotti C., De Natale P., Di Sarno V., Maddaloni P., Maccaferri G., Mura A., Negusini M., Levi F., Perini F., Ricci R., Roma M., Amato Santamaria L., Siciliani de Cumis M., Stagni M., Tuozzi A., Calonico D.
Affiliazione autori: Ist Nazl Ric Metrol INRIM, Str Cacce 91, I-10135 Turin, Italy; CNR, INO, Via Campi Flegrei 34, Pozzuoli, Italy; Complesso Univ MS Angelo, Sez Napoli, INFN, Via Cintia, Naples, Italy; ASI, Ctr Geodesia Spaziale G Colombo, CGS, Matera, Italy; INAF, IRA, Ist Radioastron, Via Gobetti 101, Bologna, Italy; ASI, Rome, Italy
Abstract: Among the most powerful techniques for the exploration of the Universe is very long baseline interferometry (VLBI), which is based on the simultaneous observation of radio sources in the sky with arrays of distant ground-based antennas. One of the effects currently limiting its ultimate sensitivity is the phase-instability of the reference clocks adopted at each antenna. This term can be made negligible delivering the same clock signal to multiple telescope sites using optical fibers. We realized such an infrastructure by disseminating a coherent optical frequency signal to two distant radio telescopes using a 1739-km-long fiber. We performed a 24 h geodetic VLBI campaign in which the same clock reference was used at both telescopes and analyzed it using standard VLBI procedures. The results were consistent with the expectations, con-firming 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. (c) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Volume: 7 (8) Da Pagina: 1031 A: 1037
Parole chiavi: FREQUENCY; GEODESY; BANDDOI: 10.1364/OPTICA.393356Citazioni: 20dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2022-09-25Riferimenti tratti da Isi Web of Knowledge: (solo abbonati) Link per visualizzare la scheda su IsiWeb: Clicca quiLink per visualizzare la citazioni su IsiWeb: Clicca qui