Extremely-bright submillimeter galaxies beyond the Lupus-I star-forming
  region
  We report detections of two candidate distant submillimeter galaxies (SMGs),
MM J154506.4$-$344318 and MM J154132.7$-$350320, which are discovered in the
AzTEC/ASTE 1.1 mm survey toward the Lupus-I star-forming region. The two
objects have 1.1 mm flux densities of 43.9 and 27.1 mJy, and have
Herschel/SPIRE counterparts as well. The Submillimeter Array counterpart to the
former SMG is identified at 890 $\mu$m and 1.3 mm. Photometric redshift
estimates using all available data from the mid-infrared to the radio suggest
that the redshifts of the two SMGs are $z_{\rm photo} \simeq$ 4-5 and 3,
respectively. Near-infrared objects are found very close to the SMGs and they
are consistent with low-$z$ ellipticals, suggesting that the high apparent
luminosities can be attributed to gravitational magnification. The cumulative
number counts at $S_{\rm 1.1mm} \ge 25$ mJy, combined with other two 1.1-mm
brightest sources, are $0.70 ^{+0.56}_{-0.34}$ deg$^{-2}$, which is consistent
with a model prediction that accounts for flux magnification due to strong
gravitational lensing. Unexpectedly, a $z > 3$ SMG and a Galactic dense
starless core (e.g., a first hydrostatic core) could be similar in the
mid-infrared to millimeter spectral energy distributions and spatial structures
at least at $\gtrsim 1"$. This indicates that it is necessary to distinguish
the two possibilities by means of broad band photometry from the optical to
centimeter and spectroscopy to determine the redshift, when a compact object is
identified toward Galactic star-forming regions.
