We present a multi-wavelength analysis of five submillimeter sources ( S _ { \mathrm { 1.1 mm } } = 0.54–2.02 mJy ) that were detected during our 1.1-mm-deep continuum survey in the SXDF-UDS-CANDELS field ( 2 arcmin ^ { 2 } , 1 \sigma = 0.055 mJy beam ^ { -1 } ) using the Atacama Large Millimeter/submillimeter Array ( ALMA ) .
The two brightest sources correspond to a known single-dish ( AzTEC ) selected bright submillimeter galaxy ( SMG ) , whereas the remaining three are faint SMGs newly uncovered by ALMA .
If we exclude the two brightest sources , the contribution of the ALMA-detected faint SMGs to the infrared extragalactic background light is estimated to be \sim 4.1 ^ { +5.4 } _ { -3.0 } Jy deg ^ { -2 } , which corresponds to \sim 16 ^ { +22 } _ { -12 } \% of the infrared extragalactic background light .
This suggests that their contribution to the infrared extragalactic background light is as large as that of bright SMGs .
We identified multi-wavelength counterparts of the five ALMA sources .
One of the sources ( SXDF-ALMA3 ) is extremely faint in the optical to near-infrared region despite its infrared luminosity ( L _ { \mathrm { IR } } \simeq 1 \times 10 ^ { 12 } \LO or SFR \simeq 100 \MO yr ^ { -1 } ) .
By fitting the spectral energy distributions ( SEDs ) at the optical-to-near-infrared wavelengths of the remaining four ALMA sources , we obtained the photometric redshifts ( z _ { \mathrm { photo } } ) and stellar masses ( M _ { * } ) : z _ { \mathrm { photo } } \simeq 1.3 – 2.5 , M _ { * } \simeq ( 3.5 – 9.5 ) \times 10 ^ { 10 } \MO .
We also derived their star formation rates ( SFRs ) and specific SFRs ( sSFRs ) as \simeq 30 – 200 \MO yr ^ { -1 } and \simeq 0.8 – 2 Gyr ^ { -1 } , respectively .
These values imply that they are main-sequence star-forming galaxies .