Ultra-bright CO and [CI] emission in a lensed z=2.04 submillimeter
  galaxy with extreme molecular gas properties
  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_CO(3-2)=52.2+-0.9 Jy km s^-1 and component CO32-B with I_CO(3-2)=15.7+-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 IRAM
30m telescope (CO(4-3) and [CI](1-0) transitions). The star-formation
efficiency of ~100 L_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 ~60~Myr,
intrinsic infrared star-formation SFR_IR approx. 2000 M_sun yr^-1 and gas
fraction M_mol/M_star=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 M_mol~15x10^11 M_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.
