Planck's dusty GEMS. IV. Star formation and feedback in a maximum starburst at z=3 seen at 60-pc resolution

Understand

We present an analysis of high-resolution ALMA interferometry of CO(4-3) line emission and dust continuum in the "Ruby" (PLCK_G244.8+54.9), a bright, gravitationally lensed galaxy at z = 3.0 discovered with the Planck all-sky survey.

• The Ruby is the brightest of Planck's Dusty GEMS, a sample of 11 of the brightest gravitationally lensed high-redshift galaxies on the extragalactic sub-mm sky.
• We resolve the high-surface-brightness continuum and CO line emission of the Ruby in several extended clumps along a partial, nearly circular Einstein ring with 1.4" diameter around a massive galaxy at z = 1.5.
• Local star-formation intensities are up to 2000 M$_{\odot}$ yr$^{-1}$ kpc$^{-2}$, amongst the highest observed at high redshift, and clearly in the range of maximal starbursts.