Datasets obtained by 2014-2017 NRO Legacy Projects have been released.
The NRO Star Formation Legacy Project, COMING Legacy Project and FUGIN Legacy Project have released their datasets. The datasets will be fundamental datasets for future studies of star formation; it will be useful not only for observations using ALMA and other radio telescopes, but also for observations in infrared and other wavelengths.
[The NRO Star Formation Legacy Project] Star formation not only determines the observed properties of galaxies, but also significantly influences galaxy evolution. What drives star formation in galaxies? There is little consensus to this apparently simple question. Theoretical studies have demonstrated that once self-gravitating objects (cloud cores) form from molecular clouds, the gravitational collapses of cores lead to star formation at high rate. However, star formation is known to occur in a very slow rate in galaxies (e.g., Zuckerman & Evans 1974). It remains uncertain what make star formation inefficient. There are several processes discussed to slow down and regulate star formation, e.g., stellar feedback, magnetic field, cloud turbulence, and so on. However, it remains to be characterized observationally how these processes influence cloud structure and star formation. Toward a full understanding of star formation in Milky Way, we aim at characterizing the cloud structure and physical conditions of molecular clouds by means of wide-field mapping observations of nearby molecular clouds, Orion A (400 pc), Aquila Rift (400 pc), and M17 (2000 pc) using 12CO (1-0), 13CO (1-0), C18O (1-0), and N2H+ (1-0).
[The NRO COMING Legacy Project] Where and how did stars form in galaxies? This question must be answered for a full understanding of the star formation process in galaxies. Since stars form in molecular clouds, CO observations that trace molecular gas are necessary. However, CO imaging observations covering an entire galaxy have not been performed extensively, and our knowledge of the spatially resolved physical conditions of molecular gas has been limited. The situation strongly motivated us to conduct multi-CO line mapping observations for more than 200 galaxies. We observed nearby galaxies with the Nobeyama 45-m radio telescope in 12CO J=1–0 in On-The-Fly mode. The final observed sample consists of about 130 galaxies because of the long delay in setting up the instrument. COMING:CO Multi-line Imaging of Nearby Galaxies
[The NRO FUGIN Legacy Project] FUGIN (FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope) is a project to create an extensive wide-field radio map of the Milky Way with unprecedented high spatial resolution. The Nobeyama 45-m Radio Telescope has good eyesight (or spatial resolution), and the new FOREST receiver installed on the telescope enables us to observe ten times more efficiently than before. FUGIN was approved as one of the Nobeyama Radio Observatory legacy projects to get maximum use out of these advantages. The purpose of the legacy projects is to collect fundamental data for next-generation studies. FUGIN observed for 1,100 hours from 2014 to 2017. The observed areas covered 130 square degrees: about 83% of the area between Galactic latitudes -1 and +1 degrees and Galactic longitudes from 10 to 50 degrees and from 198 to 236 degrees. The angular resolution is about 20 arcseconds, and the radial velocity resolution for molecules is 1.3 km/s. This is about 3 times higher (※) in spatial resolution than previous data for the Milky Way. The 45-m telescope simultaneously obtained data for 3 different isotope species of carbon monoxide molecules, 12CO, 13CO, and C18O. This enabled us to study the physical characters of the gas, like temperature and density, in addition to the distribution of the molecular gas and its motions.