Millimeter multiplicity in DR21(OH): outflows, molecular cores and
  envelopes
  We present sensitive high angular resolution ($\sim$ 1$"$) millimeter
continuum and line observations from the massive star forming region DR21(OH)
located in the Cygnus X molecular cloud. Within the well-known dusty MM1-2
molecular cores, we report the detection of a new cluster of about ten compact
continuum millimeter sources with masses between 5 and 24 M$_\odot$, and sizes
of a few thousands of astronomical units. These objects are likely to be large
dusty envelopes surrounding massive protostars, some of them most probably
driving several of the outflows that emanate from this region. Additionally, we
report the detection of strong millimeter emission of formaldehyde (H$_2$CO)
and methanol (CH$_3$OH) near 218 GHz as well as compact emission from the
typical outflow tracers carbon monoxide and silicon monoxide (CO and SiO)
toward this massive star-forming region. The H$_2$CO and CH$_3$OH emission is
luminous ($\sim$ 10$^{-4}$ L$_{\odot}$), well resolved, and found along the
collimated methanol maser outflow first identified at centimeter wavelengths
and in the sources SMA6 and SMA7. Our observations suggest that this maser
outflow might be energized by a millimeter source called SMA4 located in the
MM2 dusty core. The CO and SiO emission traces some other collimated outflows
that emanate from MM1-2 cores, and are not related with the low velocity maser
outflow.
