We found that an intermediate velocity cloud (IVC) IVC 86−36 in Hi 21 cm emission shows a head-tail distribution toward the Galactic plane with marked parallel filamentary streamers, which is extended over 40 degrees in the sky. The distance of IVC 86−36 is constrained to be less than ∼ 3 kpc from absorption of a background star as determined from optical spectroscopy. There is a bridge feature in velocity between the IVC and the local ISM with velocity separation of ∼ 50 km s −1 , which may indicate dynamical interaction of the IVC with the disk. If the interaction is correct, the distance estimate d of the IVC ranges from 200 pc to 3 kpc, and the mass of the IVC head is estimated to be 7 × 10 3 (d/1kpc) 2 M . The IVC shares similar properties to the Smith cloud located at 12 kpc, including the head-tail distribution, streamers, and bridge feature, while the mass of the IVC is less than ∼ 0.1 of the Smith 1 arXiv:1711.09529v2 [astro-ph.GA] 5 Oct 2018 cloud. A comparison between the Hi and the Planck/IRAS dust emission indicates that the dust emission of IVC 86−36 is not detectable in spite of its Hi column density of 2 × 10 20 cm −2 , indicating low metalicity of IVC 86−36 by a factor of < ∼ 0.2 as compared with the solar neighbor.We conclude that IVC 86−38 is an infalling cloud which likely originated in the low-metallicity environment of the Galactic halo or the Magellanic system.

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We report the current status of the NASCO (NAnten2 Super CO survey as legacy) project which aims to provide all-sky CO data cube of southern hemisphere using the NANTEN2 4-m submillimeter telescope installed at the Atacama Desert through developing a new multi-beam receiver and a new telescope control system. The receiver consists of 5 beams. The four beams, located at the four corners of a square with the beam separation of 720 , are installed with a 100 GHz band SIS receiver having 2-polarization sideband-separation filter. The other beam, located at the optical axis, is installed with a 200 GHz band SIS receiver having 2-polarization sideband-separation filter. The cooled component is modularized for each beam, and cooled mirrors are used. The IF bandwidths are 8 and 4 GHz for 100 and 200 GHz bands, respectively. Using XFFTS spectrometers with a bandwidth of 2 GHz, the lines of 12 CO, 13 CO, and C 18 O of J=1−0 or J=2−1 can be observed simultaneously for each beam. The control system is reconstructed on the ROS architecture, which is an open source framework for robot control, to enable a flexible observation mode and to handle a large amount of data. The framework is