Molecular gas in the immediate vicinity of Sgr A* seen with ALMA
  We report serendipitous detections of line emission with ALMA in band 3, 6,
and 7 in the central parsec of the Galactic center at an up to now highest
resolution (<0.7''). Among the highlights are the very first and highly
resolved images of sub-mm molecular emission of CS, H13CO+, HC3N, SiO, SO, C2H,
and CH3OH in the immediate vicinity (~1'' in projection) of Sgr A* and in the
circumnuclear disk (CND). The central association (CA) of molecular clouds
shows three times higher CS/X (X: any other observed molecule) luminosity
ratios than the CND suggesting a combination of higher excitation - by a
temperature gradient and/or IR-pumping - and abundance enhancement due to UV-
and/or X-ray emission. We conclude that the CA is closer to the center than the
CND is and could be an infalling clump consisting of denser cloud cores
embedded in diffuse gas. Moreover, we identified further regions in and outside
the CND that are ideally suited for future studies in the scope of hot/cold
core and extreme PDR/XDR chemistry and consequent star formation in the central
few parsecs.
