Molecular gas reservoirs in cluster galaxies at z=1.46
  We present molecular gas reservoirs of eighteen galaxies associated with the
XMMXCS J2215.9-1738 cluster at z=1.46. From Band 7 and Band 3 data of the
Atacama Large Millimeter/submillimeter Array (ALMA), we detect dust continuum
emission at 870 um and CO J=2-1 emission line from 8 and 17 member galaxies
respectively within a cluster-centric radius of $R_{200}$. The molecular gas
masses derived from the CO and/or dust continuum luminosities show that the
fraction of molecular gas mass and the depletion time scale for the cluster
galaxies are larger than expected from the scaling relations of molecular gas
on stellar mass and offset from the main sequence of star-forming galaxies in
general fields. The galaxies closer to the cluster center in terms of both
projected position and accretion phase seem to show a larger deviation from the
scaling relations. We speculate that the environment of galaxy cluster helps
feed the gas through inflow to the member galaxies and also reduce the
efficiency of star formation. The stacked Band 3 spectrum of 12 quiescent
galaxies with stellar mass $\sim10^{11}$ M$_\odot$ within 0.5$R_{200}$ shows no
detection of CO emission line, giving the upper limit of molecular gas mass and
molecular gas fraction to be $<10^{10}$ M$_\odot$ and $<10$%, respectively.
Therefore, the massive galaxies in the cluster core quench the star formation
activity while consuming most of the gas reservoirs.
