HCN and HCO+ Observations of the Galactic Circumnuclear Disk

نویسنده

  • Min Yun
چکیده

We present high spatial resolution (5.1 × 2.7) Owens Valley Radio Observatory (OVRO) millimeter array observations of HCN (J=1-0) and HCO (J=10) emission in the inner 3 pc of the Galaxy (0.04 pc ∼ 1). The HCN and HCO emission of the Circumnuclear Disk (CND) is distributed in a well-defined ring with a peak at a radius of 1.6 pc. The observed radial velocities are generally consistent with rotation at ∼ 110 km s (except along the western edge of the CND). The HCO/HCN emission ratio is typically ∼ 0.4 but with significant variations. The variations in the HCO/HCN emission and absorption ratios can be attributed to greater abundances of HCO in lower density regions both within the CND and along the line-of-sight. The HCN emission is well correlated with the H2 emission at 2.12 μm both in the main emission lobes of the CND and also in four H2 and HCN filaments. Multiple areas of interaction between

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تاریخ انتشار 2007