The VLBI Observations of Astronomical Sources by using The Japanese VLBI network.

点击翻译按钮获取中文摘要

We constructed a VLBI network composed of 4 stations spread over the islands of Japan in 1993. The longest baseline of this network is 1305 km long which provides a fringe spacing of 2" and 1" at 22 and 43 GHz, respectively. The primary purpose of this research is to study the superluminal jets in the active galactic nuclei and the great clouds of astronomical maser spots in the star forming region and the circumstellar shells around the late type stars by using this VLBI network. From this, we want to make clear the true nature of the circulation and the evolution of matter in the universe.A dozen or so observations have been done or are now going on. Some of the data of maser observations were already analyzed by the multiple fringe-rate mapping method to obtain wide-field map of the masing region. Here I will review some very interesting results.Imai et al. (1997) observed water masers around 21 late type stars using this network and found that the spot size of maser spots is one or … More der smaller than that estimated so far. They also detected for the first time systematic shifts of line-of-sight velocities in time by performing VLBI monitoring observations of water masers around a semiregular variable RT Vir.Omodaka, Motizuki et al. performed VLBI monitoring observations of Orion KL bipolar outflow and discovered for the first time maser spots around the nozzle of outflow, IRc2. Also they found that these spots are accelerated. By continuing this observations we want to put on the truck of these spots and obtain very important informations of velocity field of bipolar outflow.Furuya et al. made VLBI observations of the maser spots around the low mass star S106FIR,and revealed the velocity structure associated with the proto-stellar accretion disk.On the other hand, some of the data of continuum sources associated with AGN were also analyzed. Kameno et al. observed relativistic jets associated with 3C380, and detected the proper motion of these jets. Some other very interesting results are obtained, but they are omitted. Less