Abstract
The use of submm dust continuum emission to probe the mass of interstellar
dust and gas in galaxies is empirically calibrated using samples of local star
forming galaxies, Planck observations of the Milky Way and high redshift submm
galaxies (SMGs). All of these objects suggest a similar calibration, strongly
supporting the view that the Rayleigh-Jeans (RJ) tail of the dust emission can
be used as an accurate and very fast probe of the ISM in galaxies. We present
ALMA Cycle 0 observations of the Band 7 (350 GHz) dust emission in 107 galaxies
from z = 0.2 to 2.5. Three samples of galaxies with a total of 101 galaxies
were stellar mass-selected from COSMOS to have $M_* \simeq10^11$\msun: 37 at
z$\sim0.4$, 33 at z$\sim0.9$ and 31 at z$=2$. A fourth sample with 6 IR
luminous galaxies at z = 2 was observed for comparison with the purely
mass-selected samples. From the fluxes detected in the stacked images for each
sample, we find that the ISM content has decreased a factor $6$ from $1 -
2 10^10$at both z = 2 and 0.9 down to $2 10^9$\msun
at z = 0.4. The IR luminous sample at z = 2 shows a further $4$ times
increase in M$_ISM$ compared to the equivalent non-IR bright sample at the
same redshift. The gas mass fractions are $2\pm0.5, 12\pm3, 14\pm2
~and ~53\pm3$ $\%$ for the four subsamples (z = 0.4, 0.9, 2 and IR bright
galaxies).
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