Tidal Distortion of the Envelope of an AGB Star IRS 3 near Sgr A*
  We present radio and mm continuum observations of the Galactic center taken
with the VLA and ALMA at 44 and 226 GHz, respectively. We detect radio and mm
emission from IRS 3, lying ~4.5" NW of Sgr A*, with a spectrum that is
consistent with the photospheric emission from an AGB star at the Galactic
center. Millimeter images reveal that the envelope of IRS 3, the brightest and
most extended 3.8$\mu$m Galactic center stellar source, consists of two
semi-circular dust shells facing the direction of Sgr A*. The outer
circumstellar shell at the distance of 1.6$\times10^4$ AU, appears to break up
into "fingers" of dust directed toward Sgr A*. These features coincide with
molecular CS (5-4) emission and a near-IR extinction cloud distributed between
IRS 3 and Sgr A*. The NE-SW asymmetric shape of the IRS 3 shells seen at 3.8
micron and radio are interpreted as structures that are tidally distorted by
Sgr A*. Using the kinematics of CS emission and the proper motion of IRS 3, the
tidally distorted outflowing material from the envelope after 5000 years
constrains the distance of IRS 3 to $\sim$0.7 pc in front of or $\sim$0.5 pc
behind Sgr A*. This suggests that the mass loss by stars near Sgr A* can supply
a reservoir of molecular material near Sgr A*. We also present dark features in
radio continuum images coincident with the envelope of IRS 3. These dusty stars
provide examples in which high resolution radio continuum images can identify
dust enshrouded stellar sources embedded an ionized medium.
