We report the very bright detection of cold molecular gas with the IRAM NOEMA interferometer of the strongly lensed source WISE J132934.18 + 224327.3 at z = 2.04 , the so-called Cosmic Eyebrow .
This source has a similar spectral energy distribution from optical-mid/IR to submm/radio but significantly higher fluxes than the well-known lensed SMG SMMJ 2135 , the Cosmic Eyelash at z = 2.3 .
The interferometric observations identify unambiguously the location of the molecular line emission in two components , component CO32-A with I _ { \mathrm { CO ( 3 - 2 ) } } = 52.2 \pm 0.9  Jy km s ^ { -1 } and component CO32-B with I _ { \mathrm { CO ( 3 - 2 ) } } = 15.7 \pm 0.7  Jy km s ^ { -1 } .
Thus , our NOEMA observations of the CO ( 3-2 ) transition confirm the SMG-nature of WISE J132934.18 + 224327.3 , resulting in the brightest CO ( 3-2 ) detection ever of a SMG .
In addition , we present follow-up observations of the brighter component with the Green Bank Telescope ( CO ( 1-0 ) transition ) and IRAMÂ 30m telescope ( CO ( 4-3 ) and [ CI ] ( 1-0 ) transitions ) .
The star-formation efficiency of \sim 100 L _ { \mathrm { \sun } } / ( K km s ^ { -1 }  pc ^ { 2 } ) is at the overlap region between merger-triggered and disk-like star-formation activity and the lowest seen for lensed dusty star-forming galaxies .
The determined gas depletion time \sim 60Â Myr , intrinsic infrared star-formation SFR _ { \mathrm { IR } } \approx 2000 Â M _ { \odot } Â yr ^ { -1 } and gas fraction M _ { \mathrm { mol } } /M _ { \mathrm { \ast } } = 0.44 indicates a starburst/merger triggered star-formation .
The obtained data of the cold ISM — from CO ( 1-0 ) and dust continuum — indicates a gas mass \mu M _ { \mathrm { mol } } \sim 15 \times~ { } 10 ^ { 11 } Â M _ { \mathrm { \sun } } for component CO32-A .
Its unseen brightness offers the opportunity to establish the Cosmic Eyebrow as a new reference source at z = 2 for galaxy evolution .