A broad-band spectroscopic search for CO line emission in HDF850.1: the brightest submillimetre object in the Hubble Deep Field-North

摘要: Using the 100-m Green Bank Telescope, we have conducted a cm-wavelength search for CO J = 1-0 line emission towards high-redshift, far-infrared (FIR) luminous object HDF850.1 over redshift interval 3.3 ≤ z 5.4. Despite wealth of existing multiwavelength observations, and recent identification galaxy counterpart in deep AT'-band (2.2 μm) imaging, an unambiguous spectroscopic has not yet been obtained this object. A FIR-to-radio wavelength photometric technique, however, predicts ∼90 per cent probability that is range, 5.4 (equivalent to observed redshifted frequency, 26.5 ν obs ≥ 18.0 GHz), making potential occupant 'high-redshift tail' submillimetre (submm)-selected galaxies. We also 2-1 narrower 3.9 4.3. Although do detect any object, our limits luminosity are broad agreement with median value measured current sample submm-selected objects detected high-J emission, but sufficient fully test validity technique.