ISM Masses and Star Formation at z = 1 to 6 ALMA Observations of Dust Continuum in 180 Galaxies in COSMOS

Understand

ALMA Cycle 2 observations of the long wavelength dust emission in 180 star-forming (SF) galaxies are used to investigate the evolution of ISM masses at z = 1 to 6.4.

• The ISM masses exhibit strong increases from z = 0 to $\rm <z>$ = 1.15 and further to $\rm <z>$ = 2.2 and 4.8, particularly amongst galaxies above the SF galaxy main sequence (MS).
• The galaxies with highest SFRs at $\rm <z>$ = 2.2 and 4.8 have gas masses 100 times that of the Milky Way and gas mass fractions reaching 50 to 80\%, i.e.
• gas masses 1 - 4$\times$ their stellar masses.