CMZoom: Survey Overview and First Data Release
  We present an overview of the CMZoom survey and its first data release.
CMZoom is the first blind, high-resolution survey of the Central Molecular Zone
(CMZ; the inner 500 pc of the Milky Way) at wavelengths sensitive to the
pre-cursors of high-mass stars. CMZoom is a 500-hour Large Program on the
Submillimeter Array (SMA) that mapped at 1.3 mm all of the gas and dust in the
CMZ above a molecular hydrogen column density of 10^23 cm^-2 at a resolution of
~3" (0.1 pc). In this paper, we focus on the 1.3 mm dust continuum and its data
release, but also describe CMZoom spectral line data which will be released in
a forthcoming publication. While CMZoom detected many regions with rich and
complex substructure, its key result is an overall deficit in compact
substructures on 0.1 - 2 pc scales (the compact dense gas fraction: CDGF). In
comparison with clouds in the Galactic disk, the CDGF in the CMZ is
substantially lower, despite having much higher average column densities. CMZ
clouds with high CDGFs are well-known sites of active star formation. The
inability of most gas in the CMZ to form compact substructures is likely
responsible for the dearth of star formation in the CMZ, surprising considering
its high density. The factors responsible for the low CDGF are not yet
understood but are plausibly due to the extreme environment of the CMZ, having
far-reaching ramifications for our understanding of the star formation process
across the cosmos.
