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We present the high angular resolution and high sensitivity images of the"Circum-Nuclear Disk (CND)" and its surrounding region of Milky Way Galaxy inthe CS J=2-1, SiO v=0 J=2-1, H^13CO^+ J=1-0, C^34S J=2-1, and CH_3OH J_{K_a,K_c}=2_{1,1}-1_{1,0}A_{--} emission lines using ALMA. The CND is recognized asa torus-like molecular gas with gaps in these emission lines except for theCH_3OH emission line. The inner and outer radii of the CND are estimated to beR_in~1.5 and R_out~2 pc, respectively. The velocities of the rotation andradial motion are estimated to be V_rot~115 km s^-1 and V_rad~23 km s^-1,respectively. The LTE molecular gas mass is estimated to be M_LTE~3x10^4 Mo. Wealso found some anomalous molecular clouds in the surrounding region. One ofthe molecular clouds is positionally connected to a part of the CND adjacent tothe "Western Arc". However, the cloud is seen to rotate in the oppositedirection to the CND. The molecular cloud would be falling currently from theouter region to the CND and being disrupted by the tidal shear of SagittariusA*(Sgr A*) because the velocity is not yet assimilated into that of the CND.Another molecular cloud is continuously connected to the tip of the "EasternArm (EA)". The velocity of this cloud is consistent with that of the ionizedgas in the EA. These facts suggest that the molecular cloud is falling from theouter region to the vicinity of Sgr A*, being disrupted by the tidal shear, andionized by strong UV emission from the Central Cluster because the impactparameter of the cloud is smaller than the first cloud. These falling cloudswould play an important role in transferring material from the outer region tothe CND and/or the vicinity of Sgr A*.

ALMA View of the Circum-nuclear Disk of the Galactic Center; Tidally-disrupted Molecular Clouds falling to the Galactic Center