ALMA Detection of Extreme Blue-Shifted Ionized Gas Within 0.2 pc of Sgr
  A* from -480 to -300 km/s
  We have used the capabilities of ALMA to probe the ionized gas towards the
Galactic center with the H30alpha mm hydrogen recombination line within 30'' of
the Galaxy's dynamical center. The observations are made with spatial and
spectral resolutions of 0.46'' X 0.35'' and 3 km/s, respectively. Multiple
compact and extended sources are detected in the mini-cavity region with
extreme negative radial velocities ranging from -480 to -300 km/s, 2-3''
(0.08-0.12 pc) from Sgr A*. This is the highest radial velocity of ionized gas
detected beyond the inner 1'' of Sgr A*. This new component is kinematically
isolated from the orbiting ionized gas. The detected gas has a velocity
gradient ranging from -50 to -200 km/s per arcsecond located to the southwest
of Sgr A* at a position angle of roughly -160 degrees. Previous proper motion
measurements in the immediate vicinity of these extreme high-velocity ionized
components have been measured and show transverse velocities that range from
313 - 865 km/s. If we assume that they are associated with each other, then the
total velocity implies these components are gravitationally unbound. In
addition, we report the kinematics of cometary radio and infrared sources.
These sources are diagonally distributed with a position angle of roughly 50
degrees within 14'' of Sgr A*. We interpret the highly blue-shifted features to
the SW where the mini-cavity is located and red-shifted cometary sources to the
NE in terms of the interaction of a collimated outflow with an opening angle of
roughly 30 degrees. An expected mass outflow rate of 2E-7 or 4E-5 solar mass
per yr is estimated by a relativistic jet-driven outflow or collimated stellar
winds, respectively.
