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Understanding the dust content of galaxies, its evolution with redshift and its relationship to stars and star formation is fundamental for our understanding of galaxy evolution. Using the ALMA Lensing Cluster Survey (ALCS) wide-area band-6 continuum dataset ($\sim\,$110 arcmin$^2$ across 33 lensing clusters), we aimed at constraining the dust mass evolution with redshift, stellar mass and star formation rate (SFR). After binning sources according to redshift, SFR and stellar mass -- extracted from an HST-IRAC catalog -- we performed a set of continuum stacking analyses in the image domain using \textsc{LineStacker} on sources between $z=1$ and $z=5$, further improving the depth of our data. The large field of view provided by the ALCS allows us to reach a final sample of $\sim4000$ galaxies with known coordinates and SED-derived physical parameters. We stack sources with SFR between $10^{-3}$ and $10^{3}$ M$_\odot$ per year, and stellar mass between $10^{8}$ and $10^{12}$ M$_\odot$, splitting them in different stellar mass and SFR bins. Through stacking we retrieve the continuum 1.2\,mm flux, a known dust mass tracer, allowing us to derive the dust mass evolution with redshift and its relation with SFR and stellar mass. We observe clear continuum detections in the majority of the subsamples. From the non detections we derive 3-$\sigma$ upper limits. We observe a steady decline in the average dust mass with redshift. Moreover, sources with higher stellar mass or SFR have higher dust mass on average, allowing us to derive scaling relations. Our results are mostly in good agreement with models at $z\sim1$-3, but indicate typically lower dust-mass than predicted at higher redshift.

The Calar Alto Void Integral-field Treasury surveY (CAVITY) is a legacy project aimed at characterising the population of galaxies inhabiting voids, which are the most under-dense regions of the cosmic web, located in the Local Universe. This paper describes the first public data release (DR1) of CAVITY, comprising science-grade optical data cubes for the initial 100 out of a total of $\sim$300 galaxies in the Local Universe ($0.005 < z < 0.050$). These data were acquired using the integral-field spectrograph PMAS/PPak mounted on the 3.5m telescope at the Calar Alto observatory. The DR1 galaxy sample encompasses diverse characteristics in the color-magnitude space, morphological type, stellar mass, and gas ionisation conditions, providing a rich resource for addressing key questions in galaxy evolution through spatially resolved spectroscopy. The galaxies in this study were observed with the low-resolution V500 set-up, spanning the wavelength range 3745-7500 \AA, with a spectral resolution of 6.0 \AA\ (FWHM). Here, we describe the data reduction and characteristics and data structure of the CAVITY datasets essential for their scientific utilisation, highlighting such concerns as vignetting effects, as well as the identification of bad pixels and management of spatially correlated noise. We also provide instructions for accessing the CAVITY datasets and associated ancillary data through the project's dedicated database., Comment: 17 pages, 9 figures, 5 tables. Accepted for publication in A&A (replacement after minor language edits)

We present results from Atacama Large Millimeter/submillimeter Array (ALMA) spectral line-scan observations at 3-mm and 2-mm bands of three near-infrared-dark (NIR-dark) galaxies behind two massive lensing clusters MACS J0417.5-1154 and RXC J0032.1+1808. Each of these three sources is a faint (de-lensed $S_{\text{1.2 mm}}$ $<$ 1 mJy) triply lensed system originally discovered in the ALMA Lensing Cluster Survey. We have successfully detected CO and [C I] emission lines and confirmed that their spectroscopic redshifts are $z=3.652$, 2.391, and 2.985. By utilizing a rich multi-wavelength data set, we find that the NIR-dark galaxies are located on the star formation main sequence in the intrinsic stellar mass range of log ($M_*$/$M_\odot$) = 9.8 - 10.4, which is about one order of magnitude lower than that of typical submillimeter galaxies (SMGs). These NIR-dark galaxies show a variety in gas depletion times and spatial extent of dust emission. One of the three is a normal star-forming galaxy with gas depletion time consistent with a scaling relation, and its infrared surface brightness is an order of magnitude smaller than that of typical SMGs. Since this galaxy has an elongated axis ratio of $\sim 0.17$, we argue that normal star-forming galaxies in an edge-on configuration can be heavily dust-obscured. This implies that existing deep WFC3/F160W surveys may miss a fraction of typical star-forming main-sequence galaxies due to their edge-on orientation., Comment: 23 pages, 10 figures, 5 tables, Accepted for publication on ApJ

New JWST/NIRCam wide-field slitless spectroscopy provides redshifts for four z>8 galaxies located behind the lensing cluster MACS J0416.1-2403. Two of them, "Y1" and "JD", have previously reported spectroscopic redshifts based on ALMA measurements of [OIII] 88 $\mu$m and/or [CII] 157.7 $\mu$m lines. Y1 is a merging system of three components, and the existing redshift z=8.31 is confirmed. However, JD is at z=8.34 instead of the previously claimed z=9.28. JD's close companion, "JD-N", which was a previously discovered z>8 candidate, is now identified at the same redshift as JD. JD and JD-N form an interacting pair. A new candidate at z>8, "f090d_018", is also confirmed and is at z=8.49. These four objects are likely part of an overdensity that signposts a large structure extending ~165 kpc in projected distance and ~48.7 Mpc in radial distance. They are magnified by less than one magnitude and have intrinsic $M_{UV}$ ranging from -19.57 to -20.83 mag. Their spectral energy distributions show that the galaxies are all very young with ages ~ 4-18 Myr and stellar masses about $10^{7-8}$ ${\rm M_\odot}$. These infant galaxies have very different star formation rates ranging from a few to over a hundred $\rm{M_\odot}$ yr$^{-1}$, but only two of them (JD and f090d_018) have blue rest-frame UV slopes $\beta<-2.0$ indicative of a high Lyman-continuum photon escape fraction that could contribute significantly to the cosmic hydrogen-reionizing background. Interestingly, these two galaxies are the least massive and least active ones among the four. The other two systems have much flatter UV slopes largely because of their high dust extinction ($A_{\rm V}$=0.9-1.0 mag). Their much lower indicated escape fractions show that even very young, actively star-forming galaxies can have negligible contribution to reionization when they quickly form dust throughout their bodies., Comment: 18 pages, 6 figures, after addressing the referee report

The Universe is shaped as a web-like structure, formed by clusters, filaments, and walls that leave large volumes in between named voids. Galaxies in voids have been found to be of a later type, bluer, less massive, and to have a slower evolution than galaxies in denser environments (filaments and walls). However, the effect of the void environment on their stellar population properties is still unclear. We aim to address this question using 118 optical integral field unit datacubes from the Calar Alto Void Integral-field Treasury surveY (CAVITY), observed with the PMAS/PPaK spectrograph at the 3.5m telescope at the Calar Alto Observatory (Almer\'ia, Spain). We used the non-parametric full spectral fitting code STARLIGHT to estimate their stellar population properties: stellar mass, stellar mass surface density, age, star formation rate (SFR), and specific star formation rate (sSFR). We analysed the results through the global and spatially resolved properties. Then, we compared them with a control sample of galaxies in filaments and walls from the CALIFA survey, matched in stellar mass and morphological type. Key findings include void galaxies having a slightly higher half-light radius (HLR), lower stellar mass surface density, and younger ages across all morphological types, and slightly elevated SFR and sSFR (only significant enough for Sas). Many of these differences appear in the outer parts of spiral galaxies in voids (HLR > 1), which are younger and exhibit a higher sSFR, indicative of less evolved discs. This trend is also found for early-type spirals, suggesting a slower transition from star-forming to quiescent states in voids. Our analysis indicates that void galaxies, influenced by their surroundings, undergo a more gradual evolution, especially in their outer regions, with a more pronounced effect for low-mass galaxies., Comment: 24 pages, 22 figures, 5 tables. Accepted for publication in A&A. Updated references list

MACS J0600.1-2008 (MACS0600) is an X-ray luminous, massive galaxy cluster at $z_{\mathrm{d}}=0.43$, studied previously by the REionization LensIng Cluster Survey (RELICS) and ALMA Lensing Cluster Survey (ALCS) projects which revealed a complex, bimodal mass distribution and an intriguing high-redshift object behind it. Here, we report on the results of a combined analysis of the extended strong lensing (SL), X-ray, Sunyaev-Zeldovich (SZ), and galaxy luminosity-density properties of this system. Using new JWST and ground-based Gemini-N and Keck data, we obtain 13 new spectroscopic redshifts of multiply imaged galaxies and identify 12 new photometric multiple-image systems and candidates, including two multiply imaged $z\sim7$ objects. Taking advantage of the larger areal coverage, our analysis reveals an additional bimodal, massive SL structure which we measure spectroscopically to lie adjacent to the cluster and whose existence was implied by previous SL-modeling analyses. While based in part on photometric systems identified in ground-based imaging requiring further verification, our extended SL model suggests that the cluster may have the second-largest critical area and effective Einstein radius observed to date, $A_{\mathrm{crit}}\simeq2.16 \mathrm{arcmin}^2$ and $\theta_{\mathrm{E}}=49.7''\pm5.0''$ for a source at $z_{\mathrm{s}}=2$, enclosing a total mass of $M(<\theta_{\mathrm{E}})=(4.7\pm0.7)\times10^{14} \mathrm{M}_{\odot}$. These results are also supported by the galaxy luminosity distribution, the SZ and X-ray data. Yet another, probably related massive cluster structure, discovered in X-rays $5'$ (1.7 Mpc) further north, suggests that MACS0600 is part of an even larger filamentary structure. This discovery adds to several recent detections of massive structures around SL galaxy clusters and establishes MACS0600 as a prime target for future high-redshift surveys with JWST., Comment: Accepted for publication in MNRAS. Version updated to the accepted paper

Sub/millimeter galaxies are a key population for the study of galaxy evolution because the majority of star formation at high redshifts occurred in galaxies deeply embedded in dust. To search for this population, we have performed an extensive survey with ALMA, called the ALMA Lensing Cluster Survey (ALCS). This survey covers 133 arcmin^2 area and securely detects 180 sources at z~0.5-6 with a flux limit of ~0.2 mJy at 1.2 mm (Fujimoto et al. 2023). Here we report the results of multi-wavelength spectral energy distribution (SED) analysis of the whole ALCS sample, utilizing the observed-frame UV to millimeter photometry. We find that the majority of the ALCS sources lie on the star-forming main sequence, with a smaller fraction showing intense starburst activities. The ALCS sample contains high infrared-excess sources IRX=log(Ldust/LUV)>1), including two extremely dust-obscured galaxies (IRX>5). We also confirm that the ALCS sample probes a broader range in lower dust mass than conventional SMG samples in the same redshift range. We identify six heavily obscured AGN candidates that are not detected in the archival Chandra data in addition to the three X-ray AGNs reported by Uematsu et al. (2023). The inferred AGN luminosity density shows a possible excess at z=2-3 compared with that determined from X-ray surveys below 10 keV., Comment: 27 pages, 20 figures

Void galaxies are essential for understanding the physical processes that drive galaxy evolution because they are less affected by external factors than galaxies in denser environments, that is, in filaments, walls, and clusters. The stellar metallicity of a galaxy traces the accumulated fossil record of the star formation through the entire life of the galaxy. A comparison of the stellar metallicity of galaxies in various environments, including voids, filaments, walls, and clusters can provide valuable insights into how the large-scale environment affects the chemical evolution of the galaxy. We present the first comparison of the relation of the total stellar mass versus central stellar metallicity between galaxies in voids, filaments, walls, and clusters with different star formation history (SFH) types, morphologies, and colours for stellar masses between $10^{8.0}$ to $10^{11.5}$ solar masses and redshift $0.01

We report galaxy MACS0416-Y3 behind the lensing cluster MACSJ0416.1--2403 as a tentative rotating disk at $z=8.34$ detected through its [OIII]$\lambda5007$ emission in JWST NIRCam wide-field slitless spectroscopic observations. The discovery is based on our new grism dynamical modeling methodology for JWST NIRCam slitless spectroscopy, using the data from ``Median-band Astrophysics with the Grism of NIRCam in Frontier Fields'' (MAGNIF), a JWST Cycle-2 program. The [OIII]$\lambda5007$ emission line morphology in grism data shows velocity offsets compared to the F480M direct imaging, suggestive of rotation. Assuming a geometrically thin disk model, we constrain the rotation velocity of $v_{\rm rot}=58^{+53}_{-35}$ km s$^{-1}$ via forward modeling of the two-dimensional (2D) spectrum. We obtain the kinematic ratio of $v_{\rm rot}/\sigma_v=1.6^{+1.9}_{-0.9}$, where $\sigma_v$ is the velocity dispersion, in line with a quasi-stable thin disk. The resulting dynamical mass is estimated to be $\log(M_{\rm dyn}/M_{\odot})=8.4^{+0.5}_{-0.7}$. If the rotation confirmed, our discovery suggests that rotating gaseous disks may have already existed within 600 million years after Big Bang., Comment: 15 pages, 6 figures. Comments welcome

We develop new tools for continuum and spectral stacking of ALMA data, and apply these to the ALMA Lensing Cluster Survey (ALCS). We derive average dust masses, gas masses and star formation rates (SFR) from the stacked observed 260~GHz continuum of 3402 individually undetected star-forming galaxies, of which 1450 are cluster galaxies and 1952 field galaxies, over three redshift and stellar mass bins (over $z = 0$-1.6 and log $M_{*} [M_{\odot}] = 8$-11.7), and derive the average molecular gas content by stacking the emission line spectra in a SFR-selected subsample. The average SFRs and specific SFRs of both cluster and field galaxies are lower than those expected for Main Sequence (MS) star-forming galaxies, and only galaxies with stellar mass of log $M_{*} [M_{\odot}] = 9.35$-10.6 show dust and gas fractions comparable to those in the MS. The ALMA-traced average `highly obscured' SFRs are typically lower than the SFRs observed from optical to near-IR spectral analysis. Cluster and field galaxies show similar trends in their contents of dust and gas, even when field galaxies were brighter in the stacked maps. From spectral stacking we find a potential CO ($J=4\to3$) line emission (SNR $\sim4$) when stacking cluster and field galaxies with the highest SFRs., Comment: 13 pages, 8 figures, 1 table (+4 pages, 4 figures in Appendix). Accepted for publication in MNRAS

We present a statistical study of 180 dust continuum sources identified in 33 massive cluster fields by the ALMA Lensing Cluster Survey (ALCS) over a total of 133 arcmin$^{2}$ area, homogeneously observed at 1.2 mm. ALCS enables us to detect extremely faint mm sources by lensing magnification, including near-infrared (NIR) dark objects showing no counterparts in existing {\it Hubble Space Telescope} and {\it Spitzer} images. The dust continuum sources belong to a blind sample ($N=141$) with S/N $\gtrsim$ 5.0 (a purity of $>$ 0.99) or a secondary sample ($N=39$) with S/N= $4.0-5.0$ screened by priors. With the blind sample, we securely derive 1.2-mm number counts down to $\sim7$ $\mu$Jy, and find that the total integrated 1.2mm flux is 20.7$^{+8.5}_{-6.5}$ Jy deg$^{-2}$, resolving $\simeq$ 80 % of the cosmic infrared background light. The resolved fraction varies by a factor of $0.6-1.1$ due to the completeness correction depending on the spatial size of the mm emission. We also derive infrared (IR) luminosity functions (LFs) at $z=0.6-7.5$ with the $1/V_{\rm max}$ method, finding the redshift evolution of IR LFs characterized by positive luminosity and negative density evolution. The total (=UV+IR) cosmic star-formation rate density (SFRD) at $z>4$ is estimated to be $161^{+25}_{-21}$ % of the established measurements, which were almost exclusively based on optical$-$NIR surveys. Although our general understanding of the cosmic SFRD is unlikely to change beyond a factor of 2, these results add to the weight of evidence for an additional ($\approx 60$ %) SFRD component contributed by the faint-mm population, including NIR dark objects., Comment: ApJS in press, 34 pages, 8 Tables, and 18 Figures (+38 pages, 5 Tables, and 6 Figures in Appendix)

We report the discovery of a triply imaged active galactic nucleus (AGN), lensed by the galaxy cluster MACS J0035.4-2015 ($z_{\mathrm{d}}=0.352$). The object is detected in Hubble Space Telescope imaging taken for the RELICS program. It appears to have a quasi-stellar nucleus consistent with a point-source, with a de-magnified radius of $r_e\lesssim100$ pc. The object is spectroscopically confirmed to be an AGN at $z_{\mathrm{spec}}=2.063\pm0.005$ showing broad rest-frame UV emission lines, and is detected in both X-ray observations with Chandra and in ALCS ALMA band 6 (1.2 mm) imaging. It has a relatively faint rest-frame UV luminosity for a quasar-like object, $M_{\mathrm{UV},1450}=-19.7\pm0.2$. The object adds to just a few quasars or other X-ray sources known to be multiply lensed by a galaxy cluster. Some diffuse emission from the host galaxy is faintly seen around the nucleus and there is a faint object nearby sharing the same multiple-imaging symmetry and geometric redshift, possibly an interacting galaxy or a star-forming knot in the host. We present an accompanying lens model, calculate the magnifications and time delays, and infer physical properties for the source. We find the rest-frame UV continuum and emission lines to be dominated by the AGN, and the optical emission to be dominated by the host galaxy of modest stellar mass $M_{\star}\simeq10^{9.2} \mathrm{M}_{\odot}$. We also observe some variation in the AGN emission with time, which may suggest that the AGN used to be more active. This object adds a low-redshift counterpart to several relatively faint AGN recently uncovered at high redshifts with HST and JWST., Comment: Published in MNRAS. Corrected miss-assignment of affiliations in the author list

We report the multi-wavelength properties of millimeter galaxies hosting X-ray detected active galactic nuclei (AGNs) from the ALMA Lensing Cluster Survey (ALCS). ALCS is an extensive survey of well-studied lensing clusters with ALMA, covering an area of 133 arcmin$^2$ over 33 clusters with a 1.2 mm flux-density limit of ${\sim}$60 $\mathrm{\mu Jy}$ ($1\sigma$). Utilizing the archival data of Chandra, we identify three AGNs at $z=$1.06, 2.09, and 2.84 among the 180 millimeter sources securely detected in the ALCS (of which 155 are inside the coverage of Chandra). The X-ray spectral analysis shows that two AGNs are not significantly absorbed ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2} < 23$), while the other shows signs of moderate absorption ($\log N_{\mathrm{H}}/\mathrm{cm}^{-2}\sim 23.5$). We also perform spectral energy distribution (SED) modelling of X-ray to millimeter photometry. We find that our X-ray AGN sample shows both high mass accretion rates (intrinsic 0.5--8 keV X-ray luminosities of ${\sim}10^{\text{44--45}}\,\mathrm{erg\ s^{-1}}$) and star-formation rates (${\gtrsim}100\,M_{\odot}\,\mathrm{yr}^{-1}$). This demonstrates that a wide-area survey with ALMA and Chandra can selectively detect intense growth of both galaxies and supermassive black holes (SMBHs) in the high-redshift universe., Comment: 14 pages, 3 figures, 2 tables

The radio galaxy NGC 1052 casts absorption features of sulfur-bearing molecules, H$_2$S, SO, SO$_2$, and CS toward the radio continuum emission from the core and jets. Using ALMA, we have measured the equivalent widths of SO absorption features in multiple transitions and determined the temperatures of $344 \pm 43$ K and $26 \pm 4$ K in sub-millimeter and millimeter wavelengths, respectively. Since sub-mm and mm continuum represents the core and jets, the high and low temperatures of the absorbers imply warm environment in the molecular torus and cooler downstream flows. The high temperature in the torus is consistent with the presence of 22-GHz H$_2$O maser emission, vibrationally excited HCN and HCO$^+$ absorption lines, and sulfur-bearing molecules in gas phase released from dust. The origin of the sulfur-bearing gas is ascribed to evaporation of icy dust component through jet-torus interaction. Shock heating is the sole plausible mechanism to maintain such high temperature of gas and dust in the torus. Implication of jet-torus interaction also supports collimation of the sub-relativistic jets by gas pressure of the torus., Comment: Accepted to ApJ, 17 pages, 7 figures

We conduct a $^{12}$C$^{16}$O($J$=1-0) (hereafter CO) mapping survey of 64 galaxies in the Fornax cluster using the ALMA Morita array in cycle 5. CO emission is detected from 23 out of the 64 galaxies. Our sample includes dwarf, spiral and elliptical galaxies with stellar masses of $M_{\rm star}\sim10^{6.3-11.6}$~M$_\odot$. The achieved beam size and sensitivity are $15''\times8''$ and $\sim12$~mJy~beam$^{-1}$ at the velocity resolution of $\sim10$~km~s$^{-1}$, respectively. We study the cold-gas (molecular- and atomic-gas) properties of 38 subsamples with $M_{\rm star}>10^9$~M$_\odot$ combined with literature HI data. We find that: (1) the low star-formation (SF) activity in the Fornax galaxies is caused by the decrease in the cold-gas mass fraction with respect to stellar mass (hereafter, gas fraction) rather than the decrease of the SF efficiency from the cold gas; (2) the atomic-gas fraction is more heavily reduced than the molecular-gas fraction of such galaxies with low SF activity. A comparison between the cold-gas properties of the Fornax galaxies and their environmental properties suggests that the atomic gas is stripped tidally and by the ram pressure, which leads to the molecular gas depletion with an aid of the strangulation and consequently SF quenching. Pre-processes in the group environment would also play a role in reducing cold-gas reservoirs in some Fornax galaxies., Comment: 53 pages, 41 figures, accepted for publication in ApJS

Direct observations of low-mass, low-metallicity galaxies at $z\gtrsim4$ provide an indispensable opportunity for detailed inspection of the ionization radiation, gas flow, and metal enrichment in sources similar to those that reionized the Universe. Combining the James Webb Space Telescope (JWST), VLT/MUSE, and ALMA, we present detailed observations of a strongly lensed, low-mass ($\approx 10^{7.6}$ ${\rm M}_\odot$) galaxy at $z=3.98$ (also see Vanzella et al. 2022). We identify strong narrow nebular emission, including CIV $\lambda\lambda1548,1550$, HeII $\lambda1640$, OIII] $\lambda\lambda1661,1666$, [NeIII] $\lambda3868$, [OII] $\lambda3727$, and Balmer series of Hydrogen from this galaxy, indicating a metal-poor HII region ($\lesssim 0.12\ {\rm Z}_\odot$) powered by massive stars. Further, we detect a metal-enriched damped Ly$\alpha$ system (DLA) associated with the galaxy with the HI column density of $N_{\rm{HI}}\approx 10^{21.8}$ cm$^{-2}$. The metallicity of the associated DLA may reach the super solar metallicity (${\gtrsim Z}_\odot$). Moreover, thanks to JWST and gravitational lensing, we present the resolved UV slope ($\beta$) map at the spatial resolution of $\approx 100$ pc at $z=4$, with steep UV slopes reaching $\beta \approx -2.5$ around three star-forming clumps. Combining with low-redshift analogs, our observations suggest that low-mass, low-metallicity galaxies, which dominate reionization, could be surrounded by a high covering fraction of the metal-enriched, neutral-gaseous clouds. This implies that the metal enrichment of low-mass galaxies is highly efficient, and further support that in low-mass galaxies, only a small fraction of ionizing radiation can escape through the interstellar or circumgalactic channels with low column-density neutral gas., Comment: 4 figures, 1 table; Accepted for Publication in the ApJL

We present a set of multi-wavelength mosaics and photometric catalogs in the ALMA lensing cluster survey (ALCS) fields. The catalogs were built by reprocessing of archival data from the CHArGE compilation, taken by the $\textit{Hubble Space Telescope}$ ($\textit{HST}$) in the RELICS, CLASH and Hubble Frontier Fields. Additionally we have reconstructed the $\textit{Spitzer}$ IRAC 3.6 and 4.5 $\mu$m mosaics, by utilising all the available archival IRSA/SHA exposures. To alleviate the effect of blending in such a crowded region, we have modelled the $\textit{Spitzer}$ photometry by convolving the $\textit{HST}$ detection image with the $\textit{Spitzer}$ PSF using the novel $\texttt{golfir}$ software. The final catalogs contain 218,000 sources, covering a combined area of 690 arcmin$^2$. These catalogs will serve as an important tool in aiding the search of the sub-mm galaxies in future ALMA surveys, as well as follow ups of the $\textit{HST}$ dark - IRAC sources. Coupled with the available $\textit{HST}$ photometry the addition of the 3.6 and 4.5 $\mu$m bands will allow us to place a better constraint on photometric redshifts and stellar masses of these objects, thus giving us an opportunity to identify high-redshift candidates for spectroscopic follow ups and answer the important questions regarding the epoch of reionization and formation of first galaxies., Comment: 41 pages, 16 figures, 8 tables. Accepted to ApJS. Mosaics and photometric catalogs can be accessed online https://github.com/dawn-cph/alcs-clusters

We present an ALMA-Herschel joint analysis of sources detected by the ALMA Lensing Cluster Survey (ALCS) at 1.15 mm. Herschel/PACS and SPIRE data at 100-500 $\mu$m are deblended for 180 ALMA sources in 33 lensing cluster fields that are either detected securely (141 sources; in our main sample) or tentatively at S/N$\geq$4 with cross-matched HST/Spitzer counterparts, down to a delensed 1.15-mm flux density of $\sim0.02$ mJy. We performed far-infrared spectral energy distribution modeling and derived the physical properties of dusty star formation for 125 sources (109 independently) that are detected at $>2\sigma$ in at least one Herschel band. 27 secure ALCS sources are not detected in any Herschel bands, including 17 optical/near-IR-dark sources that likely reside at $z=4.2\pm1.2$. The 16-50-84 percentiles of the redshift distribution are 1.15-2.08-3.59 for ALCS sources in the main sample, suggesting an increasing fraction of $z\simeq1-2$ galaxies among fainter millimeter sources ($f_{1150}\sim 0.1$ mJy). With a median lensing magnification factor of $\mu = 2.6_{-0.8}^{+2.6}$, ALCS sources in the main sample exhibit a median intrinsic star-formation rate of $94_{-54}^{+84}\,\mathrm{M}_\odot\,\mathrm{yr}^{-1}$, lower than that of conventional submillimeter galaxies at similar redshifts by a factor of $\sim$3. Our study suggests weak or no redshift evolution of dust temperature with $L_\mathrm{IR}<10^{12}\,\mathrm{L}_\odot$ galaxies within our sample at $z \simeq 0 - 2$. At $L_\mathrm{IR}>10^{12}\,\mathrm{L}_\odot$, the dust temperatures show no evolution across $z \simeq 1 -4$ while being lower than those in the local Universe. For the highest-redshift source in our sample ($z=6.07$), we can rule out an extreme dust temperature ($>$80 K) that was reported for MACS0416 Y1 at $z=8.31$., Comment: 44 pages, 23 figures, 4 tables, accepted for publication in ApJ

We present Atacama Large Millimeter/submillimeter Array observations of multiple CO(1-0), $^{13}$CO(1-0), and C$^{18}$O(1-0) lines and 2.9 mm and 1.3 mm continuum emission toward the nearby interacting luminous infrared galaxy NGC 3110, supplemented with similar spatial resolution H$\alpha$, 1.4GHz continuum, and $K$-band data. We estimate the typical CO-to-H$_2$ conversion factor of 1.7 $M_{\odot}$ (K km s$^{-1}$ pc$^2$)$^{-1}$ within the disk using LTE-based and dust-based H$_2$ column densities, and measure the 1-kpc scale surface densities of star formation rate ($\Sigma_{\rm SFR}$), super star clusters ($\Sigma_{\rm SSC}$), molecular gas mass, and star formation efficiency (SFE) toward the entire gas disk. These parameters show a peak at the southern part of the southern spiral arm (SFE $\sim$ 10$^{-8.2}$ yr$^{-1}$, $\Sigma_{\rm SFR}$ $\sim$ 10$^{-0.6}$ $M_{\odot}$ kpc$^{-2}$ yr$^{-1}$, $\Sigma_{\rm SSC}$ $\sim$ 6.0 kpc$^{-2}$), which is likely attributed to the on-going tidal interaction with the companion galaxy MCG-01-26-013, as well as toward the circumnuclear region. We also find that thermal free-free emission contributes to a significant fraction of the millimeter continuum emission at the southern peak position. Those measurements imply that the peak of the southern arm is an active and young star-forming region, whereas the central part of NGC 3110 is a site of long-continued star formation. We suggest that, during the early stage of the galaxy-galaxy interaction with large mass ratio that in NGC 3110, fragmentation along the main galaxy's arms is an important driver of merger-induced star formation and massive gas inflow results in dusty nuclear starbursts., Comment: 17 pages, 9 figures, 2 tables, accepted for publication in The Astrophysical Journal

While some galactic bars show recent massive star formation (SF) along them, some others present a lack of it. Whether bars with low level of SF are a consequence of low star formation efficiency (SFE), low gas inflow rate, or dynamical effects, remains a matter of debate. We perform a multi-wavelength analysis of 12 strongly barred massive galaxies, chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1-0) and CO(2-1) emission within bars with the IRAM-30m telescope, which we use to estimate molecular gas masses. SF rates (SFR) are calculated from GALEX near- and far- ultraviolet (UV) and WISE 12 and 22 micron images within the beam pointings, covering the full bar extent. We detect molecular gas along the bars of all probed galaxies. The SFE in bars varies between galaxies by up to an order of magnitude. On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature. Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with lowest SFEs and SFR surface densities (NGC 4548 and NGC 5850) are also the ones hosting massive bulges and signs of past interactions with nearby companions. The SFE in strong bars is not systematically inhibited (either in the central, mid- or end-parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work (Abridged)., Comment: Accepted for publication in A&A (June 22, 2021). 18 pages, 9 figures, 2 tables, plus appendices (16 pages, 18 figures, 3 tables)

The properties of galaxies at redshift $z>6$ hold the key to our understanding of the early stages of galaxy evolution and can potentially identify the sources of the ultraviolet radiation that give rise to the epoch of reionisation. The far-infrared cooling line of [CII] at 158$\mu$m is known to be bright and correlate with the star formation rate (SFR) of low-redshift galaxies, and hence is also suggested to be an important tracer of star formation and interstellar medium properties for very high-redshift galaxies. With the aim to study the interstellar medium properties of gravitationally lensed galaxies at $z>6$, we search for [CII] and thermal dust emission in a sample of 52 $z\sim6$ galaxies observed by the ALMA Lensing Cluster Survey (ALCS). We perform our analysis using \textsc{LineStacker}, stacking both [CII] and continuum emission. The target sample is selected from multiple catalogues, and the sample galaxies have spectroscopic redshift or low-uncertainty photometric redshifts ($\sigma_z < 0.02$) in nine galaxy clusters. Source properties of the target galaxies are either extracted from the literature or computed using spectral energy distribution (SED) fitting. Both weighted-average and median stacking are used, on both the full sample and three sub-samples. Our analyses find no detection of either [CII] or continuum. An upper limit on $L_{\rm [CII]}$ is derived, implying that [CII] remains marginally consistent for low-SFR $z>6$ galaxies but likely is under-luminous compared to the local $L_{\rm [CII]}$-SFR relationship. We discuss potential biases and possible physical effects that may be the cause of the non-detection. Further, the upper limit on the dust continuum implies that less than half of the star formation is obscured.

We present results obtained from ALMA CO (2-1) data of the double-barred galaxy NGC 3504. With three times higher angular resolution (~ 0."8) than previous studies, our observations reveal an inner molecular gas bar, a nuclear ring, and four inner spiral arm-like structures in the central 1 kpc region. Furthermore, the CO emission is clearly aligned with the two dust lanes in the outer bar region, with differences in shape and intensity between them. The total molecular gas mass in the observed region (50"x57") is estimated to be $\sim 3.1\times 10^9 \, {\rm M}_{\odot}$, which is 17 per cent of the stellar mass. We used the Kinemetry package to fit the velocity field and found that circular motion strongly dominates at $R= 0.3-0.8$ kpc, but radial motion becomes important at $R<0.3$ kpc and $R=1.0-2.5$ kpc, which is expected due to the presence of the inner and outer bars. Finally, assuming that the gas moves along the dust lanes in the bar rotating frame, we derived the pattern speed of the outer bar to be $ 18\pm5$ km s$^{-1}$ kpc$^{-1}$, the average streaming velocities on each of the two dust lanes to be 165 and 221 km s$^{-1}$, and the total mass inflow rate along the dust lanes to be 12 M$_{\odot}$ yr$^{-1}$. Our results give a new example of an inner gas bar within a gas-rich double-barred galaxy and suggest that the formation of double-barred galaxies could be associated with the existence of such gas structures., Comment: Accepted for publication in MNRAS, 18 pages, 18 figures, 1 table

We present a study of the incidence of active galactic nucleus (AGN) in a sample of major merging systems at 0.3

We present bright [CII] 158 $\mu$m line detections from a strongly magnified and multiply-imaged ($\mu\sim20-160$) sub-$L^{*}$ ($M_{\rm UV}$ = $-19.75^{+0.55}_{-0.44}$) Lyman-break galaxy (LBG) at $z=6.0719\pm0.0004$ from the ALMA Lensing Cluster Survey (ALCS). Emission lines are identified at 268.7 GHz at $\geq$ 8$\sigma$ exactly at positions of two multiple images of the LBG behind the massive galaxy cluster RXCJ0600$-$2007. Our lens models, updated with the latest spectroscopy from VLT/MUSE, indicate that a sub region of the LBG crosses the caustic and is lensed into a long ($\sim6''$) arc with a local magnification of $\mu\sim 160$, for which the [CII] line is also significantly detected. The source-plane reconstruction resolves the interstellar medium (ISM) structure, showing that the [CII] line is co-spatial with the rest-frame UV continuum at the scale of $\sim$300 pc. The [CII] line properties suggest that the LBG is a rotation-dominated system whose velocity gradient explains a slight difference of redshifts between the whole LBG and its sub region. The star formation rate (SFR)-$L_{\rm [CII]}$ relations from the sub to the whole regions of the LBG are consistent with those of local galaxies. We evaluate the lower limit of the faint-end of the [CII] luminosity function at $z=6$, and find that it is consistent with predictions from semi analytical models and from the local SFR-$L_{\rm [CII]}$ relation with a SFR function at $z=6$. These results imply that the local SFR-$L_{\rm [CII]}$ relation is universal for a wide range of scales including the spatially resolved ISM, the whole region of galaxy, and the cosmic scale, even in the epoch of reionization., Comment: 27 pages, 10 figures, 6 tables, ApJ in press

We report ALMA observations of NGC 1052 to quest mass accretion in a gas-poor active galactic nucleus (AGN). We detected CO emission representing a rotating ring-like circumnuclear disk (CND) seen edge-on with the gas mass of $5.3 \times 10^{5}$ M$_{\odot}$. The CND has smaller gas mass than that in typical Seyfert galaxies with circumnuclear star formation and is too gas-poor to drive mass accretion onto the central engine. The continuum emission casts molecular absorption features of CO, HCN, HCO$^+$, SO, SO$_2$, CS, CN, and H$_2$O, with H$^{13}$CN and HC$^{15}$N and vibrationally-excited (v$_2 = 1$) HCN and HCO$^+$. Broader absorption line widths than CND emission line widths imply presence of a geometrically thick molecular torus with a radius of $2.4 \pm 1.3$ pc and a thickness ratio of $0.7 \pm 0.3$. We estimate the H$_2$ column density of $(3.3 \pm 0.7) \times 10^{25}$ cm$^{-2}$ using H$^{12}$CN, H$^{13}$CN, and HCO$^{+}$ absorption features and adopting abundance ratio of $^{12}$C-to-$^{13}$C and a HCO$^{+}$-to-H$_2$, and derived the torus gas mass of $(1.3 \pm 0.3) \times 10^7$ M$_{\odot}$, which is $\sim 9$\% of the central black-hole mass. The molecular gas in the torus is clumpy with the estimated covering factor of $0.17^{+0.06}_{-0.03}$. The gas density of clumps inside the torus is inferred to be $(6.4 \pm 1.3) \times 10^7$ cm$^{-3}$, which meets the excitation conditions of H$_2$O maser. Specific angular momentum in the torus exceeds a flat-rotation curve extrapolated from that of the CND, indicating a Keplerian rotation inside a 14.4-pc sphere of influence., Comment: Accepted for publication in ApJ, 27 pages, 13 figures, 7 tables

We present the results of $^{12}$CO($J$=1-0) mosaicing observations of the cD galaxy NGC 1316 at kpc-resolution performed with the Morita Array of the Atacama Large Millimeter/submillimeter Array (ALMA). We reveal the detailed distribution of the molecular gas in the central region for the first time: a shell structure in the northwest, a barely resolved blob in the southeast of the center and some clumps between them. The total molecular gas mass obtained with a standard Milky-Way CO-to-H$_2$ conversion factor is $(5.62 \pm 0.53)\times10^8$ M$_\odot$, which is consistent with previous studies. The disturbed velocity field of the molecular gas suggests that the molecular gas is injected very recently ($<1$ Gyr) if it has an external origin and is in the process of settling into a rotating disk. Assuming that a low-mass gas-rich galaxy has accreted, the gas-to-dust ratio and H$_2$-to-HI ratio are unusually low ($\sim 28$) and high ($\sim 5.6$), respectively. To explain these ratios, additional processes should be taken into accounts such as an effective dust formation and conversion from atomic to molecular gas during the interaction. We also discuss the interaction between the nuclear jet and the molecular gas., Comment: 16 pages, 8 figures, 3 tables, accepted for publication in PASJ

We report detections of two 1.2 mm continuum sources ($S_\mathrm{1.2mm}$ ~ 0.6 mJy) without any counterparts in the deep $H$- and/or $K$-band image (i.e., $K$-band magnitude $\gtrsim$ 26 mag). These near-infrared-dark faint millimeter sources are uncovered by ASAGAO, a deep and wide-field ($\simeq$ 26 arcmin$^2$) Atacama Large Millimeter/submillimeter Array (ALMA) 1.2 mm survey. One has a red IRAC (3.6 and 4.5 $\mu$m) counterpart, and the other has been independently detected at 850 and 870 $\mu$m using SCUBA2 and ALMA Band 7, respectively. Their optical to radio spectral energy distributions indicate that they can lie at $z \gtrsim$ 3-5 and can be in the early phase of massive galaxy formation. Their contribution to the cosmic star formation rate density is estimated to be ~ 1 $\times$ 10$^{-3}$ $M_\odot$ yr$^{-1}$ Mpc$^{-3}$ if they lie somewhere in the redshift range of $z$ ~ 3-5. This value can be consistent with, or greater than that of bright submillimeter galaxies ($S_\mathrm{870\mu m}>$ 4.2 mJy) at $z$ ~ 3-5. We also uncover 3 more candidates near-infrared-dark faint ALMA sources without any counterparts ($S_\mathrm{1.2mm}$ ~ 0.45-0.86 mJy). These results show that an unbiased ALMA survey can reveal the dust-obscured star formation activities, which were missed in previous deep optical/near-infrared surveys., Comment: 10 pages, 6 figures, accepted for publication in ApJ

We examined radial variations in molecular-gas based star formation efficiency (SFE), which is defined as star formation rate per unit molecular gas mass, for 80 galaxies selected from the CO Multi-line Imaging of Nearby Galaxies project (Sorai et al. 2019). The radial variations in SFE for individual galaxies are typically a factor of 2 -- 3, which suggests that SFE is nearly constant along galactocentric radius. We found the averaged SFE in 80 galaxies of $(1.69 \pm 1.1) \times 10^{-9}$ yr$^{-1}$, which is consistent with Leroy et al. 2008 if we consider the contribution of helium to the molecular gas mass evaluation and the difference in the assumed initial mass function between two studies. We compared SFE among different morphological (i.e., SA, SAB, and SB) types, and found that SFE within the inner radii ($r/r_{25} < 0.3$, where $r_{25}$ is $B$-band isophotal radius at 25 mag arcsec$^{-2}$) of SB galaxies is slightly higher than that of SA and SAB galaxies. This trend can be partly explained by the dependence of SFE on global stellar mass, which probably relates to the CO-to-H$_2$ conversion factor through the metallicity. For two representative SB galaxies in our sample, NGC 3367 and NGC 7479, the ellipse of $r/r_{25}$ = 0.3 seems to cover not only the central region but also the inner part of the disk, mainly the bar. These two galaxies show higher SFE in the bar than in spiral arms. However, we found an opposite trend in NGC 4303; SFE is lower in the bar than in spiral arms, which is consistent with earlier studies (e.g., Momose et al. 2010). These results suggest diversity of star formation activities in the bar., Comment: 28 pages, 12 figures, accepted for publication in PASJ

We present high-spatial-resolution ($\sim 0\farcs2$, or $\sim$3\,pc) CO(2--1) observations of the nearest young starburst dwarf galaxy, NGC\,5253, taken with the Atacama Large Millimeter/submillimeter Array. We have identified 118 molecular clouds with average values of 4.3\,pc in radius and 2.2\,\kms\, in velocity dispersion, which comprise the molecular cloud complexes observed previously with $\sim$100\,pc resolution. We derive for the first time in this galaxy the $I{\rm (CO)}$--$N$(H$_2$) conversion factor, $X$ = $4.1^{+5.9}_{-2.4}\times10^{20}$\,cm$^{-2}$(K\,\kms)$^{-1}$, based on the virial method. The line-width and mass-to-size relations of the resolved molecular clouds present an offset on average toward higher line-widths and masses with respect to quiescent regions in other nearby spiral galaxies and our Galaxy. The offset in the scaling relation reaches its maximum in regions close to the central starburst, where velocity dispersions are $\sim$ 0.5 dex higher and gas mass surface densities are as high as $\Sigma_{\rm H_2}$ = 10$^3$\,\Msol\,pc $^{-2}$. These central clouds are gravitationally bound despite the high internal pressure. A spatial comparison with star clusters found in the literature enables us to identify six clouds that are associated with young star clusters. Furthermore, the star formation efficiencies (SFEs) of some of these clouds exceed those found in star-cluster-forming clouds within our Galaxy. We conclude that once a super star cluster is formed, the parent molecular clouds are rapidly dispersed by the destructive stellar feedback, which results in such a high SFE in the central starburst of NGC\,5253., Comment: 18 pages, 11 figures, accepted to ApJ

We present the survey design, data reduction, construction of images, and source catalog of the Atacama Large Millimeter/submillimeter Array (ALMA) twenty-six arcmin^2 survey of GOODS-S at one-millimeter (ASAGAO). ASAGAO is a deep (1sigma ~ 61 uJy/beam for a 250 klambda-tapered map with a synthesized beam size of 0.51" x 0.45") and wide area (26 arcmin^2) survey on a contiguous field at 1.2 mm. By combining with ALMA archival data in the GOODS-South field, we obtained a deeper map in the same region (1sigma ~ 30 uJy/beam for a deep region with a 250 klambda-taper, and a synthesized beam size of 0.59" x 0.53"), providing the largest sample of sources (25 sources at >=5.0sigma, 45 sources at >=4.5sigma) among ALMA blank-field surveys to date. The number counts shows that 52(+11 -8)% of the extragalactic background light at 1.2 mm is resolved into discrete sources at S1.2m > 135 uJy. We create infrared (IR) luminosity functions (LFs) in the redshift range of z = 1-3 from the ASAGAO sources with KS-band counterparts, and constrain the faintest luminosity of the LF at 2.0 < z < 3.0. The LFs are consistent with previous results based on other ALMA and SCUBA-2 observations, which suggest a positive luminosity evolution and negative density evolution with increasing redshift. We find that obscured star-formation of sources with IR luminosities of log(L(IR)/Lsun)} ~> 11.8 account for ~~60%-90% of the z ~ 2 cosmic star-formation rate density., Comment: 19 pages, 18 figures, accepted for publication in PASJ

We present high-resolution observations (0".2-1".5) of multiple dense gas tracers, HCN and HCO$^+$ ($J$ = 1-0, 3-2, and 4-3), HNC ($J$ = 1-0), and CS ($J$ = 7-6) lines, toward the nearby luminous infrared galaxy VV 114 with the Atacama Large Millimeter/submillimeter Array. All lines are robustly detected at the central gaseous filamentary structure including the eastern nucleus and the Overlap region, the collision interface of the progenitors. We found that there is no correlation between star formation efficiency and dense gas fraction, indicating that the amount of dense gas does not simply control star formation in VV 114. We predict the presence of more turbulent and diffuse molecular gas clouds around the Overlap region compared to those at the nuclear region assuming a turbulence-regulated star formation model. The intracloud turbulence at the Overlap region might be excited by galaxy-merger-induced shocks, which also explains the enhancement of gas-phase CH$_3$OH abundance previously found there. We also present spatially resolved spectral line energy distributions of HCN and HCO$^+$ for the first time, and derive excitation parameters by assuming optically-thin and local thermodynamic equilibrium (LTE) conditions. The LTE model revealed that warmer, HCO$^+$-poorer molecular gas medium is dominated around the eastern nucleus, harboring an AGN. The HCN abundance is remarkably flat ($\sim$3.5 $\times$ 10$^{-9}$) independently of the various environments within the filament of VV 114 (i.e., AGN, star formation, and shock)., Comment: 23 pages, 21 figures (downconverted), 5 tables, accepted for publication in ApJ

We present morphological properties of dusty star-forming galaxies at z=1-3 determined with high-resolution (FWHM~0"19) Atacama Large Milllimeter/submilimeter Array (ALMA) 1-mm band maps of our ASAGAO survey covering a 26-arcmin^2 area in GOODS-S. In conjunction with the ALMA archival data, the present sample consists of 42 ALMA sources with a wide rest-frame far-infrared (FIR) luminosity L_FIR range of ~10^11-10^13 Lo. To obtain an average rest-frame FIR profile, we perform individual measurements and careful stacking of the ALMA sources using the uv-visibility method that includes positional-uncertainty and smoothing-effect evaluations through Monte-Carlo simulations. We find that the dusty star-forming galaxies have the average FIR-wavelength Sersic index and effective radius of n_FIR=1.2+/-0.2 and R_e,FIR=1.0-1.3 kpc, respectively, additionally with a point source at the center, indicative of the existence of AGN. The average FIR profile agrees with a morphology of an exponential-disk clearly distinguished from a spheroidal profile (Sersic index of 4). We also examine the rest-frame optical Sersic index n_opt and effective radius R_e,opt with the deep Hubble Space Telescope (HST) images. Interestingly, we obtain n_opt=0.9+/-0.3 (~n_FIR) and R_e,opt=3.2+/-0.6 kpc (>R_e,FIR), suggesting that the FIR-emitting disk is embedded within a larger stellar disk. The rest-frame UV and FIR data of HST and ALMA provide us a radial surface density profile of the total star-formation rate (SFR), where the FIR SFR dominates over the UV SFR at the center. Under the simple assumption of a constant SFR, a compact stellar distribution found in z~1-2 compact quiescent galaxies (cQGs) is well reproduced, while a spheroidal stellar morphology of cQGs (n_opt=4) cannot, suggestive of other important mechanisms such as dynamical dissipation., Comment: 13 pages, 6 figures, ApJ in press

Centaurus A, with its gas-rich elliptical host galaxy, NGC 5128, is the nearest radio galaxy at a distance of 3.8 Mpc. Its proximity allows us to study the interaction between an active galactic nucleus, radio jets, and molecular gas in great detail. We present ALMA observations of low J transitions of three CO isotopologues, HCN, HCO$^{+}$, HNC, CN, and CCH toward the inner projected 500 pc of NGC 5128. Our observations resolve physical sizes down to 40 pc. By observing multiple chemical probes, we determine the physical and chemical conditions of the nuclear interstellar medium of NGC 5128. This region contains molecular arms associated with the dust lanes and a circumnuclear disk (CND) interior to the molecular arms. The CND is approximately 400 pc by 200 pc and appears to be chemically distinct from the molecular arms. It is dominated by dense gas tracers while the molecular arms are dominated by $^{12}$CO and its rare isotopologues. The CND has a higher temperature, elevated CN/HCN and HCN/HNC intensity ratios, and much weaker $^{13}$CO and C$^{18}$O emission than the molecular arms. This suggests an influence from the AGN on the CND molecular gas. There is also absorption against the AGN with a low velocity complex near the systemic velocity and a high velocity complex shifted by about 60 km s$^{-1}$. We find similar chemical properties between the CND in emission and both the low and high velocity absorption complexes implying that both likely originate from the CND. If the HV complex does originate in the CND, then that gas would correspond to gas falling toward the supermassive black hole.

We present the largest catalogue of HI single dish observations of isolated galaxies to date and the corresponding HI scaling relations, as part of the multi-wavelength project AMIGA (Analysis of the interstellar Medium in Isolated GAlaxies). Despite numerous studies of the HI content of galaxies, no revision has been made for the most isolated L* galaxies since 1984. In total we have measurements or constraints on the HI masses of 844 galaxies from the Catalogue of Isolated Galaxies (CIG), obtained with our own observations at Arecibo, Effelsberg, Nancay and GBT, and spectra from the literature. Cuts are made to this sample to ensure isolation and a high level of completeness. We then fit HI scaling relations based on luminosity, optical diameter and morphology. Our regression model incorporates all the data, including upper limits, and accounts for uncertainties in both variables, as well as distance uncertainties. The scaling relation of HI mass with optical diameter is in good agreement with that of Haynes & Giovanelli 1984, but our relation with luminosity is considerably steeper. This is attributed to the large uncertainties in the luminosities, which introduce a bias when using OLS regression (used previously), and the different morphology distributions of the samples. We find that the main effect of morphology on the relations is to increase the intercept and flatten the slope towards later types. These trends were not evident in previous works due to the small number of detected early-type galaxies. The HI scaling relations of the AMIGA sample define an up-to-date metric of the HI content of almost "nurture free" galaxies. These relations allow the expected HI mass, in the absence of interactions, of a galaxy to be predicted to within 0.25 dex, and are thus suitable for use as statistical measures of the impact of interactions on the neutral gas content of galaxies. (Abridged), Comment: 29 pages, 14 figures, 16 tables. Accepted for publication in A&A. Full data tables will be main available with the final publication

We present high-resolution (1".0) Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO (1-0) and CO (2- 1) rotational transitions toward the nearby IR-luminous merger NGC 1614 supplemented with ALMA archival data of CO (3-2), and CO (6-5) transitions. The CO (6-5) emission arises from the starburst ring (central 590 pc in radius), while the lower-$J$ CO lines are distributed over the outer disk ($\sim$ 3.3 kpc in radius). Radiative transfer and photon dominated region (PDR) modeling reveal that the starburst ring has a single warmer gas component with more intense far-ultraviolet radiation field ($n_{\rm{H_2}}$ $\sim$ 10$^{4.6}$ cm$^{-3}$, $T_{\rm{kin}}$ $\sim$ 42 K, and $G_{\rm{0}}$ $\sim$ 10$^{2.7}$) relative to the outer disk ($n_{\rm{H_2}}$ $\sim$ 10$^{5.1}$ cm$^{-3}$, $T_{\rm{kin}}$ $\sim$ 22 K, and $G_{\rm{0}}$ $\sim$ 10$^{0.9}$). A two-phase molecular interstellar medium with a warm and cold ($>$ 70 K and $\sim$ 19 K) component is also an applicable model for the starburst ring. A possible source for heating the warm gas component is mechanical heating due to stellar feedback rather than PDR. Furthermore, we find evidence for non-circular motions along the north-south optical bar in the lower-$J$ CO images, suggesting a cold gas inflow. We suggest that star formation in the starburst ring is sustained by the bar-driven cold gas inflow, and starburst activities radiatively and mechanically power the CO excitation. The absence of a bright active galactic nucleus can be explained by a scenario that cold gas accumulating on the starburst ring is exhausted as the fuel for star formation, or is launched as an outflow before being able to feed to the nucleus., Comment: 20 pages, 19 figures, 2 tables, accepted for publication in ApJ

We report the detection of two CH$_3$OH lines (J$_K$ = 2$_K$-1$_K$ and 3$_K$-2$_K$) between the progenitor's disks ("Overlap") of the mid-stage merging galaxy VV 114 obtained using the Atacama Large Millimeter/submillimeter Array (ALMA) Band 3 and Band 4. The detected CH$_3$OH emission show an extended filamentary structure (~ 3 kpc) across the progenitor's disks with relatively large velocity width (FWZI ~ 150 km/s). The emission is only significant in the "overlap" and not detected in the two merging nuclei. Assuming optically-thin emission and local thermodynamic equilibrium (LTE), we found the CH$_3$OH column density relative to H$_2$ ($X_{\rm CH_3OH}$) peaks at the "Overlap" (~ 8 $\times$ 10$^{-9}$), which is almost an order of magnitude larger than that at the eastern nucleus. We suggest that kpc-scale shocks driven by galaxy-galaxy collision may play an important role to enhance the CH$_3$OH abundance at the "Overlap". This scenario is consistent with that shock-induced large velocity dispersion components of ionized gas have been detected in optical wavelength at the same region. Conversely, low $X_{\rm CH_3OH}$ at the nuclear regions might be attributed to the strong photodissociation by nuclear starbursts and/or putative active galactic nucleus (AGN), or inefficient production of CH$_3$OH on dust grains due to initial high temperature conditions (i.e., desorption of the precursor molecule, CO, into gas-phase before forming CH$_3$OH on dust grains). These ALMA observations demonstrate that CH$_3$OH is a unique tool to address kpc-scale shock-induced gas dynamics and star formation in merging galaxies., Comment: 8 pages, 4 figures, 3 tables, accepted for publication in ApJ

We present the results of Atacama Large Millimeter/Submillimeter Array (ALMA) 108, 233, 352, and 691 GHz continuum observations and Very Large Array (VLA) 4.81 and 8.36 GHz observations of the nearby luminous merger remnant NGC 1614. By analyzing the beam (1".0 * 1".0) and uv (> 45 k{\lambda}) matched ALMA and VLA maps, we find that the deconvolved source size of lower frequency emission (< 108 GHz) is more compact (420 pc * 380 pc) compared to the higher frequency emission (> 233 GHz) (560 pc * 390 pc), suggesting different physical origins for the continuum emission. Based on an SED model for a dusty starburst galaxy, it is found that the SED can be explained by three components, (1) non-thermal synchrotron emission (traced in the 4.81 and 8.36 GHz continuum), (2) thermal free-free emission (traced in the 108 GHz continuum), and (3) thermal dust emission (traced in the 352 and 691 GHz continuum). We also present the spatially-resolved (sub-kpc scale) Kennicutt-Schmidt relation of NGC 1614. The result suggests a systematically shorter molecular gas depletion time in NGC 1614 (average {\tau}_gas of 49 - 77 Myr and 70 - 226 Myr at the starburst ring and the outer region, respectively) than that of normal disk galaxies (~ 2 Gyr) and a mid-stage merger VV 114 (= 0.1 - 1 Gyr). This implies that the star formation activities in U/LIRGs are efficiently enhanced as the merger stage proceeds, which is consistent with the results from high-resolution numerical merger simulations., Comment: 10 pages, 6 figures, accepted for publication in PASJ

Compiling data from literature and the ALMA archive, we show enhanced HCN(4-3)/HCO$^+$(4-3) and/or HCN(4-3)/CS(7-6) integrated intensity ratios in circumnuclear molecular gas around active galactic nuclei (AGNs) compared to those in starburst (SB) galaxies (submillimeter HCN-enhancement). The number of sample galaxies is significantly increased from our previous work. We expect this feature could potentially be an extinction-free energy diagnostic tool of nuclear regions of galaxies. Non-LTE radiative transfer modelings of the above molecular emission lines involving both collisional and radiative excitation, as well as a photon trapping effect were conducted to investigate the cause of the high line ratios in AGNs. As a result, we found that enhanced abundance ratios of HCN-to-HCO$^+$ and HCN-to-CS in AGNs as compared to SB galaxies by a factor of a few to even $>$ 10 is a plausible explanation for the submillimeter HCN-enhancement. However, a counter argument of a systematically higher gas density in AGNs than in SB galaxies can also be a plausible scenario. Although we could not fully discriminate these two scenarios at this moment due to insufficient amount of multi-transition, multi-species data, the former scenario equivalently claims for abnormal chemical composition in AGNs. Regarding the actual mechanism to realize the composition, we suggest it is difficult with conventional gas phase X-ray dominated region (XDR) ionization models to reproduce the observed high line ratios. We might have to take into account other mechanisms such as neutral-neutral reactions that are efficiently activated at high temperature environments and/or mechanically heated regions to further understand the high line ratios in AGNs., Comment: 24 pages, 12 figures, accepted for publication in ApJ

We present ALMA Cycle 1 observations of the central kpc region of the luminous type-1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.5$"$ $\times$ 0.4$"$ = 165 pc $\times$ 132 pc) at submillimeter wavelengths. Utilizing the wide-bandwidth of ALMA, we simultaneously obtained HCN(4-3), HCO$^+$(4-3), CS(7-6), and partially CO(3-2) line maps, as well as the 860 $\mu$m continuum. The region consists of the central $\sim$ 1$"$ component and the surrounding starburst ring with a radius of $\sim$ 1.5$"$-2.5$"$. Several structures connect these components. Except for CO(3-2), these dense gas tracers are significantly concentrated towards the central $\sim$ 1$"$, suggesting their suitability to probe the nuclear regions of galaxies. Their spatial distribution resembles well those of centimeter and mid-infrared continuum emissions, but it is anti-correlated with the optical one, indicating the existence of dust obscured star formation. The integrated intensity ratios of HCN(4-3)/HCO$^+$(4-3) and HCN(4-3)/CS(7-6) are higher at the AGN position than at the starburst ring, which is consistent to our previous findings (submm-HCN enhancement). However, the HCN(4-3)/HCO$^+$(4-3) ratio at the AGN position of NGC 7469 (1.11$\pm$0.06) is almost half of the corresponding value of the low-luminosity type-1 Seyfert galaxy NGC 1097 (2.0$\pm$0.2), despite the more than two orders of magnitude higher X-ray luminosity of NGC 7469. But the ratio is comparable to that of the close vicinity of the AGN of NGC 1068 ($\sim$ 1.5). Based on these results, we speculate that some other heating mechanisms than X-ray (e.g., mechanical heating due to AGN jet) can contribute significantly for shaping the chemical composition in NGC 1097., Comment: Fixed typos in the title. 15 pages, 8 figures, 4 tables: accepted for publication in ApJ. Comments welcome

We present an unprecedented measurement of the disc stability and local instability scales in the luminous infrared Seyfert 1 host, NGC7469, based on ALMA observations of dense gas tracers and with a synthesized beam of 165 x 132 pc. While we confirm that non-circular motions are not significant in redistributing the dense interstellar gas in this galaxy, we find compelling evidence that the dense gas is a suitable tracer for studying the origin of its intensely high-mass star forming ring-like structure. Our derived disc stability parameter accounts for a thick disc structure and its value falls below unity at the radii in which intense star formation is found. Furthermore, we derive the characteristic instability scale and find a striking agreement between our measured scale of ~ 180 pc, and the typical sizes of individual complexes of young and massive star clusters seen in high-resolution images., Comment: Accepted for publication in ApJ Letters

We present ALMA cycle 0 observations of the molecular gas and dust in the IR-bright mid-stage merger VV114 obtained at 160 - 800 pc resolution. The main aim of this study is to investigate the distribution and kinematics of the cold/warm gas and to quantify the spatial variation of the excitation conditions across the two merging disks. The data contain 10 molecular lines, including the first detection of extranuclear CH3OH emission in interacting galaxies, as well as continuum emission. We map the 12CO(3-2)/12CO(1-0) and the 12CO(1-0)/13CO(1-0) line ratio at 800 pc resolution (in the units of K km/s), and find that these ratios vary from 0.2 - 0.8 and 5 - 50, respectively. Conversely, the 200 pc resolution HCN(4-3)/HCO+(4-3) line ratio shows low values (< 0.5) at a filament across the disks except for the unresolved eastern nucleus which is three times higher (1.34 +/- 0.09). We conclude from our observations and a radiative transfer analysis that the molecular gas in the VV114 system consists of five components with different physical and chemical conditions; i.e., 1) dust-enshrouded nuclear starbursts and/or AGN, 2) wide-spread star forming dense gas, 3) merger-induced shocked gas, 4) quiescent tenuous gas arms without star formation, 5) H2 gas mass of (3.8 +/- 0.7) * 10^7 Msun (assuming a conversion factor of {\alpha}_CO = 0.8 Msun (K km s^-1 pc^2)^-1) at the tip of the southern tidal arm, as a potential site of tidal dwarf galaxy formation., Comment: 67 pages, 21 figures, 15 tables, ApJ accepted

We present < 1 kpc resolution CO imaging study of 37 optically-selected local merger remnants using new and archival interferometric maps obtained with ALMA, CARMA, SMA and PdBI. We supplement a sub-sample with single-dish measurements obtained at the NRO 45 m telescope for estimating the molecular gas mass (10^7 - 10^11 M_sun), and evaluating the missing flux of the interferometric measurements. Among the sources with robust CO detections, we find that 80 % (24/30) of the sample show kinematical signatures of rotating molecular gas disks (including nuclear rings) in their velocity fields, and the sizes of these disks vary significantly from 1.1 kpc to 9.3 kpc. The size of the molecular gas disks in 54 % of the sources is more compact than the K-band effective radius. These small gas disks may have formed from a past gas inflow that was triggered by a dynamical instability during a potential merging event. On the other hand, the rest (46 %) of the sources have gas disks which are extended relative to the stellar component, possibly forming a late-type galaxy with a central stellar bulge. Our new compilation of observational data suggests that nuclear and extended molecular gas disks are common in the final stages of mergers. This finding is consistent with recent major-merger simulations of gas rich progenitor disks. Finally, we suggest that some of the rotation-supported turbulent disks observed at high redshifts may result from galaxies that have experienced a recent major merger., Comment: 35 pages, 7 figures, 6 tables, accepted for publication in ApJS. For high-quality images and data products (in FITS format), see http://alma-intweb.mtk.nao.ac.jp/~jueda/data/mr/index.html

Users of the Atacama Large Millimeter/submillimeter Array (ALMA) are provided with calibration and imaging products in addition to raw data. In Cycle 0 and Cycle 1, these products are produced by a team of data reduction experts spread across Chile, East Asia, Europe, and North America. This article discusses the lines of communication between the data reducers and ALMA users that enable this model of distributed data reduction. This article also discusses the calibration and imaging scripts that have been provided to ALMA users in Cycles 0 and 1, and what will be different in future Cycles., Comment: 7 pages, Proceedings of SPIE in Montreal (2014)

We present evidence that super giant HII regions (GHRs) and other disk regions of the nearby spiral galaxy, M33, occupy distinct locations in the correlation between molecular gas, $\Sigma_{\rm H_2}$, and the star formation rate surface density, $\Sigma_{\rm SFR}$. This result is based on wide field and high sensitivity CO(3-2) observations at 100 pc resolution. Star formation efficiencies (SFE), defined as $\Sigma_{\rm SFR}$/$\Sigma_{\rm H_2}$, in GHRs are found to be about 1 dex higher than in other disk regions. The CO(3-2)/CO(1-0) integrated intensity ratio is also higher than the average over the disk. Such high SFE and CO(3-2)/CO(1-0) can reach the values found in starburst galaxies, which suggests that GHRs may be the elements building up a larger scale starburst region. Three possible contributions to high SFEs in GHR are investigated: (1) the $I_{CO}$-$N({\rm H_2})$ conversion factor, (2) the dense gas fraction traced by CO(3-2)/CO(1-0), and (3) the initial mass function (IMF). We conclude that these starburst-like properties in GHRs can be interpreted by a combination of both a top-heavy IMF and a high dense gas fraction, but not by changes in the $I_{CO}$-$N({\rm H_2})$ conversion factor., Comment: 8 pages, 7 figures, Accepted for publication in the ApJ