出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Recent Japanese e-VLBI activities are reported in this paper. Offline data transfer though the
network has been regularly performed for geodetic VLBI experiments. Besides these offline
transfers, real-time eVLBI experiments for ultra-rapid UT1 measurements have been performed
among Onsala, Metsähovi, Tsukuba, and Kashima stations in a pilot project. In the field of
astronomy, a real-time e-VLBI demonstration session organized by the ATNF in 2008 was the
first occasion for Kashima to transmit VLBI data obtained by the K5 system to a foreign correlator
in real-time. The global e-VLBI observation session organized by JIVE for the opening event of
International Year of Astronomy in January 2009 was the first participation for a Japanese station
in a global real-time e-VLBI session. Overview of the K5 DAS systems (K5/VSSP, and K5/VSI)
used for the e-VLBI is described.
Optically linked e-VLBI observations with domestic VLBI stations have been conducted by the
NAOJ. Also the NAOJ has developed a high speed VLBI data sender/reciver equipment named
VOA-200 and a high speed hardware correlator (2Gbps × 6 baselines). A test observation of 8
Gbps real-time VLBI was successfully achieved by using the VOA-200 and the hardware correlator
in 2008.
