2020ApJ...889..174B

We present evidence of 6.7 GHz methanol (CH₃OH) and 4.8 GHz formaldehyde (H₂CO) absorption toward the Galactic Center (GC) point source "N3." Both absorption features are unresolved and spatially aligned with N3. The 6.7 GHz CH₃OH contains a single-velocity component (centered at ∼10 km s^–1), while the 4.8 GHz H₂CO shows two-velocity components (centered at ∼-3 and +8 km s^–1). We find that the velocities of these absorption components are similar to that of emission lines from other molecules (e.g., SiO and HC₃N) detected toward this compact source (-13 to +25 km s^–1; "N3 cloud"). The detection of these absorption features is a firm indication that some of the molecular gas in the N3 molecular cloud is on the near side of the continuum source. Analysis of the CH₃OH absorption kinematics shows a relatively large velocity dispersion (3.8 km s^–1) for the size scale of this feature (<0.''1, <0.01 pc at the GC), when compared with other similarly sized GC clouds in the Larson line width-size relationship. Furthermore, this line width is closer to velocity dispersion measurements for size scales of 1.3 pc, which is roughly the width of the N3 cloud (25''; 1.0 pc). We argue that this relatively broad line width, over a small cross-sectional area, is due to turbulence through the depth of the cloud, where the cloud has a presumed line-of-sight thickness of ∼1 pc.