Imaging the Molecular Gas in a z=3.9 Quasar Host Galaxy at 0.3" Resolution: A Central, Sub-Kiloparsec Scale Star Formation Reservoir in APM 08279+5255

Understand

We have mapped the molecular gas content in the host galaxy of the strongly lensed high redshift quasar APM 08279+5255 (z=3.911) with the Very Large Array at 0.3" resolution.

• The CO(J=1-0) emission is clearly resolved in our maps.
• The CO(J=1-0) line luminosity derived from these maps is in good agreement with a previous single-dish measurement.
• In contrast to previous interferometer-based studies, we find that the full molecular gas reservoir is situated in two compact peaks separated by <~0.4&#34;.