We present the results of a 2′ × 3′
(3.7 Mpc× 5.5 Mpc at z = 3, in a comoving scale) deep
survey at 1.1 mm taken with ALMA in the SSA22 field (ALMA deep field in
SSA22 or ADF22).
Using a mosaic of 103 ALMA pointings, we observed the core region of a z =
3.09 proto-cluster,
achieving an typical rms sensitivity of 60 µJy beam−1 at a resolution of
0.7 arcsec. We obtained 18 robustly detected ALMA sources (here after
submillimeter galaxies, SMGs) with a signal-to-noise ratio (SNR) > 5. At
least 10 ALMA SMGs have spectroscopic redshifts of z = 3.09. We find that
multiple z = 3.09 ALMA SMGs contribute to two AzTEC sources, supporting
that interaction
may be responsible for a significant fraction of multiplicity in
single-dish sources. Not only are
these SMGs members of the proto-cluster but they in fact reside within the
node at the junction of
the 50 Mpc-scale filamentary three-dimensional structure traced by
Lyman-alpha emitters (LAEs)
in this field. We also find that six of the 10 ALMA SMGs host a X-ray
luminous active galactic
nuclei (AGN). Our results suggest that the vigorous star formation activity
and the growth of super
massive black holes (SMBHs) occurred simultaneously in the densest regions
at z ∼ 3, which is
likely to correspond to the most active historical phase of the massive
galaxy population found in
the core of the clusters in the present universe.