A Magnetic Field Connecting the Galactic Center Circumnuclear Disk with
  Streamers and Mini-spiral -Implications from 850 $\mu$m Polarization Data
  Utilizing James Clark Maxwell Telescope (JCMT) 850 $\mu$m SCUPOL dust
polarization data, we investigate the configuration of the magnetic ($B$) field
in the circumnuclear disk (CND) of the Galactic Center (GC). The SCUPOL data
show a highly improved polarization coverage and resolution compared to earlier
100 $\mu$m observations. The 850 $\mu$m data have a resolution and coverage
similar to previous 350 $\mu$m polarimetry data. However, with a proper
sampling on a 10$"$ grid, we find the 850 $\mu$m data trace the morphological
structures of the CND substantially better. Furthermore, because the 850 $\mu$m
trace the field deeper into the material near Sgr A*, they represent the
highest resolution submillimeter probe to date of the CND magnetic field. The
observed $B$-field morphology is well described by a self-similar axisymmetric
disk model where the radial infall velocity is one quarter of the rotational
velocity. A detailed comparison with higher-resolution interferometric maps
from the Submillimeter Array further reveals that the $B$-field aligns with the
neutral gas streamers connecting to the CND. Moreover, the innermost observed
$B$-field structure also appears to trace and align with the mini-spiral
located inside the CND. This suggests that there is one underlying $B$-field
structure that is connecting the CND with its streamers and the inner
mini-spiral. An estimate of $\beta_{\rm Plasma} \lesssim 1-$based on the global
B-field morphology that constrains the azimuthal-to-vertical field strength
ratio of around 40 combined with a measurement of the azimuthal
velocity--indicates that the B-field appears dynamically significant towards
the CND and also onwards to the inner mini-spiral.
