We present results of MUSE-ALMA Halos, an ongoing study of the CircumgalacticMedium (CGM) of galaxies ($z \leq$ 1.4). Using multi-phase observations weprobe the neutral, ionised and molecular gas in a sub-sample containing sixabsorbers and nine associated galaxies in the redshift range $z \sim 0.3-0.75$.Here, we give an in-depth analysis of the newly CO-detected galaxy Q2131-G1($z=0.42974$), while providing stringent mass and depletion time limits for thenon-detected galaxies. Q2131-G1 is associated with an absorber with columndensities of $\textrm{log}(N_\textrm{HI}/\textrm{cm}^{-2}) \sim 19.5$ and$\textrm{log}(N_{\textrm{H}_2}/\textrm{cm}^{-2}) \sim 16.5$, has a starformation rate of $\textrm{SFR} = 2.00 \pm 0.20 \; \textrm{M}_{\odot}\textrm{yr}^{-1}$, a dark matter fraction of $f_\textrm{DM}(r_{1/2}) = 0.24 -0.54$ and a molecular gas mass of $M_\textrm{mol} = 3.52 ^{+3.95}_{-0.31}\times 10^9 \; \textrm{M}_{\odot}$ resulting in a depletion time of$\tau_\textrm{dep} < 4.15 \; \textrm{Gyr}$. Kinematic modelling of both the CO(3--2) and [OIII] $\lambda 5008$ emission lines of Q2131-G1 shows that themolecular and ionised gas phases are well aligned directionally and that themaximum rotation velocities closely match. These two gas phases within the diskare strongly coupled. The metallicity, kinematics and orientation of the atomicand molecular gas traced by a two-component absorption feature is consistentwith being part of the extended rotating disk with a well-separated additionalcomponent associated with infalling gas. Compared to emission-selected samples,we find that HI-selected galaxies have high molecular gas masses given theirlow star formation rate. We consequently derive high depletion times for theseobjects.

We report a $\approx 400$-hour Giant Metrewave Radio Telescope (GMRT) searchfor HI 21 cm emission from star-forming galaxies at $z = 1.18-1.39$ in sevenfields of the DEEP2 Galaxy Survey. Including data from an earlier 60-hour GMRTobserving run, we co-added the HI 21 cm emission signals from 2,841 bluestar-forming galaxies that lie within the full-width at half-maximum of theGMRT primary beam. This yielded a $5.0\sigma$ detection of the average HI 21 cmsignal from the 2,841 galaxies at an average redshift $\langle z \rangle\approx 1.3$, only the second detection of HI 21 cm emission at $z\ge1$. Weobtain an average HI mass of $\langle {\rm M_{HI}} \rangle=(3.09 \pm 0.61)\times 10^{10}\ {\rm M}_\odot$ and an HI-to-stellar mass ratio of $2.6\pm0.5$,both significantly higher than values in galaxies with similar stellar massesin the local Universe. We also stacked the 1.4 GHz continuum emission of thegalaxies to obtain a median star-formation rate (SFR) of $14.5\pm1.1\ {\rmM}_\odot \textrm{yr}^{-1}$. This implies an average HI depletion timescale of$\approx 2$ Gyr for blue star-forming galaxies at $z\approx 1.3$, a factor of$\approx 3.5$ lower than that of similar local galaxies. Our results suggestthat the HI content of galaxies towards the end of the epoch of peak cosmic SFRdensity is insufficient to sustain their high SFR for more than $\approx 2$Gyr. Insufficient gas accretion to replenish the HI could then explain theobserved decline in the cosmic SFR density at $z< 1$.

We report the serendipitous identification of a low mass ($M_* \sim 2\times10^6 \, \mathrm{M}_\odot$), isolated, likely quenched dwarf galaxy in the"foreground" of the COSMOS-CANDELS field. From deep Hubble Space Telescope(HST) imaging we infer a surface brightness fluctuation distance for COSMOS-dw1of $D_{\mathrm{SBF}} = 22 \pm 3$ Mpc, which is consistent with its radialvelocity of $cz = 1222 \pm 64$ km s$^{-1}$ via Keck/LRIS. At this distance, thegalaxy is 1.4 Mpc in projection from its nearest massive neighbor. We do notdetect significant H$\alpha$ emission (EW(H$\alpha$)$ = -0.4 \pm 0.5$angstroms), suggesting that COSMOS dw1 is likely quenched. Very little iscurrently known about isolated quenched galaxies in this mass regime. Suchgalaxies are thought to be rare, as there is no obvious mechanism topermanently stop star formation in them; to date there are only four examplesof well-studied quenched field dwarfs, only two of which appear to havequenched in isolation. COSMOS-dw1 is the first example outside of the immediatevicinity of the Local Group. COSMOS-dw1 has a relatively weakD$_\mathrm{n}$4000 break and the HST data show a clump of blue stars indicatingthat star formation ceased only recently. We speculate that COSMOS-dw1 wasquenched due to internal feedback, which was able to temporarily suspend starformation. In this scenario the expectation is that quenched isolated galaxieswith masses $M_*=10^6 - 10^7$ M$_{\odot}$ generally have luminosity-weightedages $\lesssim 1$ Gyr.