We have mapped the W 3 giant molecular cloud in the C0 3P1-3 Po ([CI]) line with the Mount Fuji Submillimeter-wave Telescope. The [CI] emission is extended over the molecular cloud, having peaks at three star forming clouds; W 3(Main), W 3(OH), and AFGL 333. The [CI] emission is found to be strong in the AFGL 333 cloud. We have also observed the C18O, CCS, N2H+, and H13CO+ lines by using the Nobeyama Radio Observatory 45 m telescope. In the AFGL 333 cloud, we find two massive cores, which are highly gravitationally bound and have no sign of active star formation. The high [Co]/[CO] and [CCS]/[N2H+] abundance ratios suggest that the AFGL 333 cloud is younger than the W 3(Main) and W 3(OH) clouds.
We have constructed the Mount Fuji submillimeter-wave telescope at Nishiyasugawara (alt. 3725 m) near the summit of Mt. Fuji (alt. 3774 m). Thanks to the excellent condition of Mt. Fuji, we have successfully carried out the [CI] survey toward more than 40 square degrees of sky, including qrion MC, Taurus MC, Rosetta MC, DR 15, DR 21, NGC 1333, NGC 2264, W 3, W 44, W 51, L 134, p-Oph. Our [CI] survey have revealed that the [CI] 492 GHz emission widely extends to the molecular clouds. The spatial and velocity structures of the [CI] 492 GHz emission resemble those of 13CO J=l-0 in many molecular clouds, implying that [CI] 492 GHz and 13CO J=1-0 are emitted from the same gas. The column density of C° linearly correlates with that of CO up to high Av, suggesting that C° exist in the deep interior of molecular clouds. In several regions, we have found that the distributions of C° and CO are different from each other. The C°-rich area is found in the Hieles' cloud 2. The C+/CO/C° configuration is found in DR 15, p-Oph, M 17, Orion KL, and NGC 1333. These results indicate that an origin of C° is unrelated with the photodissociation process. We discuss the observed C° distributions in relation to the non-equilibrium chemistry.