Search

Using the Hubble Space Telescope/Advanced Camera for Surveys data in the COSMOS field, we systematically searched clumpy galaxies at 0.2 < z < 1.0 and investigated the fraction of clumpy galaxies and its evolution as a function of stellar mass, star formation rate (SFR), and specific SFR (SSFR). The fraction of clumpy galaxies in star-forming galaxies with Mstar > 109.5M☼ decreases with time from ∼0.35 at 0.8 < z < 1.0 to ∼0.05 at 0.2 < z < 0.4, irrespective of the stellar mass, although the fraction tends to be slightly lower for massive galaxies with Mstar > 1010.5M☼ at each redshift. On the other hand, the fraction of clumpy galaxies increases with increasing both SFR and SSFR in all the redshift ranges we investigated. In particular, we found that the SSFR dependences of the fractions are similar among galaxies with different stellar masses, and the fraction at a given SSFR does not depend on the stellar mass in each redshift bin. The evolution of the fraction of clumpy galaxies from z ∼ 0.9 to z ∼ 0.3 seems to be explained by such SSFR dependence of the fraction and the evolution of SSFRs of star-forming galaxies. The fraction at a given SSFR also appears to decrease with time, but this can be due to the effect of the morphological k correction. We suggest that these results are understood by the gravitational fragmentation model for the formation of giant clumps in disk galaxies, where the gas mass fraction is a crucial parameter. [ABSTRACT FROM AUTHOR]

We examine the use of submillimeter (submm) recombination lines of H, He, and He+ to probe the extreme ultraviolet (EUV) luminosity of starbursts (SBs) and active galactic nuclei (AGNs). We find that the submm recombination lines of H, He, and He+ are in fact extremely reliable and quantitative probes of the EUV continuum at 13.6 eV to above 54.6 eV. At submm wavelengths, the recombination lines originate from low energy levels (n = 20-50). The maser amplification, which poses significant problems for quantitative interpretation of the higher n, radio frequency recombination lines, is insignificant. Lastly, at submm wavelengths, the dust extinction is minimal. The submm line luminosities are therefore directly proportional to the emission measures (EMION = ne × nion × volume) of their ionized regions. We also find that the expected line fluxes are detectable with ALMA and can be imaged at ∼0.″1 resolution in low redshift ultraluminous infrared galaxies. Imaging of the H I lines will provide accurate spatial and kinematic mapping of the star formation distribution in low-z IR-luminous galaxies, and the relative fluxes of the H I and He II recombination lines will strongly constrain the relative contributions of SBs and AGNs to the luminosity. The H I lines should also provide an avenue to constraining the submm dust extinction curve. [ABSTRACT FROM AUTHOR]

We combine Herschel Photodetector Array Camera and Spectrometer and Spectral and Photometric Imaging Receiver maps of the full 2 deg2 Cosmic Evolution Survey (COSMOS) field with existing multi-wavelength data to obtain template and model-independent optical-to-far-infrared spectral energy distributions (SEDs) for 4218 Herschel-selected sources with log(LIR/L☼) = 9.4-13.6 and z = 0.02-3.54. Median SEDs are created by binning the optical to far-infrared (FIR) bands available in COSMOS as a function of infrared luminosity. Herschel probes rest-frame wavelengths where the bulk of the infrared radiation is emitted, allowing us to more accurately determine fundamental dust properties of our sample of infrared luminous galaxies. We find that the SED peak wavelength (λpeak) decreases and the dust mass (Mdust) increases with increasing total infrared luminosity (LIR). In the lowest infrared luminosity galaxies (log(LIR/L☼) = 10.0-11.5), we see evidence of polycyclic aromatic hydrocarbon (PAH) features (λ ∼ 7-9 μm), while in the highest infrared luminosity galaxies (LIR > 1012L☼) we see an increasing contribution of hot dust and/or power-law emission, consistent with the presence of heating from an active galactic nucleus (AGN). We study the relationship between stellar mass and star formation rate of our sample of infrared luminous galaxies and find no evidence that Herschel-selected galaxies follow the SFR/M* “main sequence” as previously determined from studies of optically selected, star-forming galaxies. Finally, we compare the mid-infrared to FIR properties of our infrared luminous galaxies using the previously defined diagnostic, IR8 ≡ LIR/L8, and find that galaxies with LIR ≳ 1011.3L☼ tend to systematically lie above (× 3-5) the IR8 “infrared main sequence,” suggesting either suppressed PAH emission or an increasing contribution from AGN heating. [ABSTRACT FROM AUTHOR]

Galaxy interactions/mergers have been shown to dominate the population of IR-luminous galaxies (LIR ≳ 1011.6L☼) in the local universe (z ≲ 0.25). Recent studies based on the relation between galaxies' star formation rates and stellar mass (the SFR-M* relation or the “galaxy main sequence”) have suggested that galaxy interaction/mergers may only become significant when galaxies fall well above the galaxy main sequence. Since the typical SFR at a given M* increases with redshift, the existence of the galaxy main sequence implies that massive, IR-luminous galaxies at high z may not necessarily be driven by galaxy interactions. We examine the role of galaxy interactions in the SFR-M* relation by carrying out a morphological analysis of 2084 Herschel-selected galaxies at 0.2 < z < 1.5 in the COSMOS field. Using a detailed visual classification scheme, we show that the fraction of “disk galaxies” decreases and the fraction of “irregular” galaxies increases systematically with increasing LIR out to z ≲ 1.5 and z ≲ 1.0, respectively. At LIR >1011.5L☼, ≳ 50% of the objects show evident features of strongly interacting/merger systems, where this percentage is similar to the studies of local IR-luminous galaxies. The fraction of interacting/merger systems also systematically increases with the deviation from the SFR-M* relation, supporting the view that galaxies falling above the main sequence are more dominated by mergers than the main-sequence galaxies. Meanwhile, we find that ≳ 18% of massive IR-luminous “main-sequence galaxies” are classified as interacting systems, where this population may not evolve through the evolutionary track predicted by a simple gas exhaustion model. [ABSTRACT FROM AUTHOR]

We use the large COSMOS sample of galaxies to study in an internally self-consistent way the change in the number densities of quenched early-type galaxies (Q-ETGs) of a given size over the redshift interval 0.2 < z < 1 in order to study the claimed size evolution of these galaxies. In a stellar mass bin at 1010.5 < Mgalaxy < 1011 M⊙, we see no change in the number density of compact Q-ETGs over this redshift range, while in a higher mass bin at >1011 M⊙, where we would expect merging to be more significant, we find a small decrease, by ∼30%. In both mass bins, the increase of the median sizes of Q-ETGs with time is primarily caused by the addition to the size function of larger and more diffuse Q-ETGs. At all masses, compact Q-ETGs become systematically redder toward later epochs, with a (U − V ) color difference which is consistent with a passive evolution of their stellar populations, indicating that they are a stable population that does not appreciably evolve in size. We find furthermore, at all epochs, that the larger Q-ETGs (at least in the lower mass bin) have average rest-frame colors that are systematically bluer than those of the more compact Q-ETGs, suggesting that the former are indeed younger than the latter. The idea that new, large, Q-ETGs are responsible for the observed growth in the median size of the population at a given mass is also supported by analysis of the sizes and number of the star-forming galaxies that are expected to be the progenitors of the new Q-ETGs over the same period. In the low mass bin, the new Q-ETGs appear to have ∼30% smaller half-light radii than their star-forming progenitors. This is likely due to the fading of their disks after they cease star formation. Comparison with higher redshifts shows that the median size of newly quenched galaxies roughly scales, at constant mass, as (1 + z)−1. We conclude that the dominant cause of the size evolution seen in the Q-ETG population is that the average sizes and thus stellar densities of individual Q-ETGs roughly scale with the average density of the universe at the time when they were quenched, and that subsequent size changes in individual objects, through merging or other processes, are of secondary importance, especially at masses below 1011 M⊙. [ABSTRACT FROM AUTHOR]

We explore the possibility that the G2 gas cloud falling in toward SgrA" is the mass-loss envelope of a young T Tauri star. As the star plunges to smaller radius at 1000-6000 km s-1, a strong bow shock forms where the stellar wind is impacted by the hot X-ray emitting gas in the vicinity of SgrA". For a stellar mass-loss rate of 4 × 10-8M☉ yr-1 and wind velocity 100 km s-1, the bow shock will have an emission measure (EM = n2vol) at a distance ~1016 cm, similar to that inferred from the IR emission lines. The ionization of the dense bow shock gas is potentially provided by collisional ionization at the shock front and cooling radiation (X-ray and UV) from the post shock gas. The former would predict a constant line flux as a function of distance from SgrA", while the latter will have increasing emission at lesser distances. In this model, the star and its mass-loss wind should survive pericenter passage since the wind is likely launched at 0.2 AU and this is much less than the Roche radius at pericenter (~3 AU for a stellar mass of 2M☉). In this model, the emission cloud will probably survive pericenter passage, discriminating this scenario from others. [ABSTRACT FROM AUTHOR]

We identify 42 "candidate groups" lying between 1.8 < z < 3.0 from a sample of 3502 galaxies with spectroscopic redshifts in the zCOSMOS-deep redshift survey within this same redshift interval. These systems contain three to five spectroscopic galaxies that lie within 500 kpc in projected distance (in physical space) and within 700 km s-1 in velocity. Based on extensive analysis of mock catalogs that have been generated from the Millennium simulation, we examine the likely nature of these systems at the time of observation, and what they will evolve into down to the present epoch. Although few of the "member" galaxies are likely to reside in the same halo at the epoch we observe them, 50% of the systems will have, by the present epoch, all of the member galaxies in the same halo, and almost all (93%) will have at least some of the potential members in the same halo. Most of the candidate groups can therefore be described as "proto-groups." A crude estimate of the overdensities of these structures is also consistent with the idea that these systems are being seen as they assemble.We also examine present-day halos and ask whether their progenitors would have been seen among our candidate groups. For present-day halos between 1014 and 1015 M☉ h -1, 35% should have appeared among our candidate groups, and this would have risen to 70% if our survey had been fully sampled, so we can conclude that our sample can be taken as representative of a large fraction of such systems. There is a clear excess of massive galaxies above 1010M☉ around the locations of the candidate groups in a large independent COSMOS photo-z sample, but we see no evidence in this latter data for any color differentiation with respect to the field. This is, however, consistent with the idea that such differentiation arises in satellite galaxies, as indicated at z < 1, if the candidate groups are indeed only starting to be assembled. [ABSTRACT FROM AUTHOR]

We present results of a statistical study of the cosmic evolution of the mass-dependent major-merger rate since z = 1. A stellar mass limited sample of close major-merger pairs (the CPAIR sample) was selected from the archive of the COSMOS survey. Pair fractions at different redshifts derived using the CPAIR sample and a local K-band-selected pair sample show no significant variations with stellar mass. The pair fraction exhibits moderately strong cosmic evolution, with the best-fitting function of fpair = 10-1.88(±0.03)(1 + z)2.2(±0.2). The best-fitting function for the merger rate is Rmg (Gyr-1) = 0.053 x (Mstar/1010.7 M⊙)0.3(1 + z)2.2/(1 + z/8). This rate implies that galaxies of Mstar ~ 1010-1011.5 M⊙ have undergone ~0.5-1.5 major mergers since z = 1. Our results show that, for massive galaxies (Mstar ≥ 1010.5 M⊙) at z ≤ 1, major mergers involving star-forming galaxies (i.e., wet and mixed mergers) can account for the formation of both ellipticals and red quiescent galaxies (RQGs). On the other hand, major mergers cannot be responsible for the formation of most low mass ellipticals and RQGs of Mstar ≾ 1010.3 M⊙. Our quantitative estimates indicate that major mergers have significant impact on the stellar mass assembly of the most massive galaxies (Mstar 1011.3 M⊙), but for less massive galaxies the stellar mass assembly is dominated by the star formation. Comparison with the mass-dependent (ultra)luminous infrared galaxies ((U)LIRG) rates suggests that the frequency of major-merger events is comparable to or higher than that of (U)LIRGs. [ABSTRACT FROM AUTHOR]

In order to understand environmental effects on star formation in high-redshift galaxies, we investigate the physical relationships between the star formation activity, stellar mass, and environment for z ≃1.2 galaxies in the 2 deg² COSMOS field. We estimate star formation using the [OII]λ3727 emission line and environment from the local galaxy density. Our analysis shows that for massive galaxies (M* ≳ 1010 M⊙), the fraction of [O II] emitters in high-density environments (Σ10th ≲ 3.9 Mpc-2) is 1.7 ± 0.4 times higher than in low-density environments (Σ10th ≾ 1.5 Mpc-2), while the [OII] emitter fraction does not depend on environment for low-mass M*≲1010 M⊙ galaxies. In order to understand what drives these trends, we investigate the role of companion galaxies in our sample. We find that the fraction of [OII] emitters in galaxies with companions is 2.4 ± 0.5 times as high as that in galaxies without companions at M* ≥ 1010 M⊙. In addition, massive galaxies are more likely to have companions in high-density environments. However, although the number of star-forming galaxies increases for massive galaxies with close companions and in dense environments, the average star formation rate of star-forming galaxies at a given mass is independent of environment and the presence/absence of a close companion. These results suggest that interactions and/or mergers in a high-density environment could induce star formation in massive galaxies at z ~ 1.2, increasing the fraction of star-forming galaxies with M* ≳ 1010 M⊙. [ABSTRACT FROM AUTHOR]

The relationship between galaxy star formation rates (SFRs) and stellar masses (M*) is reexamined using a mass-selected sample of ∼62,000 star-forming galaxies at z ⩽ 1.3 in the COSMOS 2 deg2 field. Using new far-infrared photometry from Herschel-PACS and SPIRE and Spitzer-MIPS 24 μm, along with derived infrared luminosities from the NRK method based on galaxies' locations in the restframe color-color diagram (NUV – r) versus (r – K), we are able to more accurately determine total SFRs for our complete sample. At all redshifts, the relationship between median SFR and M* follows a power law at low stellar masses, and flattens to nearly constant SFR at high stellar masses. We describe a new parameterization that provides the best fit to the main sequence and characterizes the low mass power-law slope, turnover mass, and overall scaling. The turnover in the main sequence occurs at a characteristic mass of about M0 ∼ 1010M☼ at all redshifts. The low mass power-law slope ranges from 0.9-1.3 and the overall scaling rises in SFR as a function of (1 + z)4.12 ± 0.10. A broken power-law fit below and above the turnover mass gives relationships of below the turnover mass and above the turnover mass. Galaxies more massive than M* ≳ 1010M☼ have a much lower average specific star formation rate (sSFR) than would be expected by simply extrapolating the traditional linear fit to the main sequence found for less massive galaxies. [ABSTRACT FROM AUTHOR]

The broad spectral bandwidth at millimeter and centimeter wavelengths provided by the recent upgrades to the Karl G. Jansky Very Large Array (VLA) has made it possible to conduct unbiased searches for molecular CO line emission at redshifts, z > 1.31. We present the discovery of a gas-rich, star-forming galaxy at z = 2.48 through the detection of CO J = 1-0 line emission in the COLDz survey and through a sensitive, Ka-band (31-39 GHz) VLA survey of a 6.5 arcmin2 region of the COSMOS field. We argue that the broad line (FWHM ∼ 570 ± 80 km s–1) is most likely to be CO J = 1-0 at z = 2.48, as the integrated emission is spatially coincident with an infrared-detected galaxy with a photometric redshift estimate of zphot = 3.2 ± 0.4. The CO J = 1-0 line luminosity is K km s–1 pc2, suggesting a cold molecular gas mass of Mgas ∼ (2-8) × 1010M☼ depending on the assumed value of the molecular gas mass to CO luminosity ratio αCO. The estimated infrared luminosity from the (rest-frame) far-infrared spectral energy distribution (SED) is LIR = 2.5 × 1012L☼ and the star formation rate is ∼250 M☼ yr–1, with the SED shape indicating substantial dust obscuration of the stellar light. The infrared to CO line luminosity ratio is ∼114 ± 19 L☼/(K km s–1 pc2), similar to galaxies with similar SFRs selected at UV/optical to radio wavelengths. This discovery confirms the potential for molecular emission line surveys as a route to study populations of gas-rich galaxies in the future. [ABSTRACT FROM AUTHOR]

Galaxies' rest-frame ultraviolet (UV) properties are often used to directly infer the degree to which dust obscuration affects the measurement of star formation rates (SFRs). While much recent work has focused on calibrating dust attenuation in galaxies selected at rest-frame ultraviolet wavelengths, locally and at high-z, here we investigate attenuation in dusty, star forming galaxies (DSFGs) selected at far-infrared wavelengths. By combining multiwavelength coverage across 0.15-500 μm in the COSMOS field, in particular making use of Herschel imaging, and a rich data set on local galaxies, we find an empirical variation in the relationship between the rest-frame UV slope (β) and the ratio of infrared-to-ultraviolet emission (LIR/LUV ≡ IRX) as a function of infrared luminosity, or total SFR. Both locally and at high-z, galaxies above SFR ≳ 50 M☼ yr–1 deviate from the nominal IRX-β relation toward bluer colors by a factor proportional to their increasing IR luminosity. We also estimate contamination rates of DSFGs on high-z dropout searches of ≪1% at z ≲ 4-10, providing independent verification that contamination from very dusty foreground galaxies is low in Lyman-break galaxy searches. Overall, our results are consistent with the physical interpretation that DSFGs, e.g., galaxies with >50 M☼ yr–1, are dominated at all epochs by short-lived, extreme burst events, producing many young O and B stars that are primarily, yet not entirely, enshrouded in thick dust cocoons. The blue rest-frame UV slopes of DSFGs are inconsistent with the suggestion that most DSFGs at z ∼ 2 exhibit steady-state star formation in secular disks. [ABSTRACT FROM AUTHOR]

We investigate the role of the delineated cosmic web/filaments on star formation activity by exploring a sample of 425 narrow-band selected Hα emitters, as well as 2846 color-color selected underlying star-forming galaxies for a large-scale structure at z = 0.84 in the COSMOS field from the HiZELS survey. Using the scale-independent Multi-scale Morphology Filter algorithm, we are able to quantitatively describe the density field and disentangle it into its major components: fields, filaments, and clusters. We show that the observed median star formation rate (SFR), stellar mass, specific SFR, the mean SFR-mass relation, and its scatter for both Hα emitters and underlying star-forming galaxies do not strongly depend on different classes of environment, in agreement with previous studies. However, the fraction of Hα emitters varies with environment and is enhanced in filamentary structures at z ∼ 1. We propose mild galaxy-galaxy interactions as the possible physical agent for the elevation of the fraction of Hα star-forming galaxies in filaments. Our results show that filaments are the likely physical environments that are often classed as the “intermediate” densities and that the cosmic web likely plays a major role in galaxy formation and evolution which has so far been poorly investigated. [ABSTRACT FROM AUTHOR]

We present spectroscopic follow-up observations on two bright Lyα emitter (LAE) candidates originally found by Krug et al. at a redshift of z ∼ 7.7 using the Multi-Object Spectrometer for Infra-Red Exploration at Keck. We rule out any line emission at the >5σ level for both objects, putting on solid ground a previous null result for one of the objects. The limits inferred from the non-detections rule out the previous claim of no or even reversed evolution between 5.7 < z < 7.7 in the Lyα luminosity function (LF) and suggest a drop in the Lyα LF consistent with that seen in Lyman break galaxy (LBG) samples. We model the redshift evolution of the LAE LF using the LBG UV-continuum LF and the observed rest-frame equivalent width distribution. From the comparison of our empirical model with the observed LAE distribution, we estimate lower limits of the neutral hydrogen fraction to be 50%-70% at z ∼ 7.7. Together with this, we find a strong evolution in the Lyα optical depth characterized by (1 + z)2.2 ± 0.5 beyond z = 6, indicative of a strong evolution of the intergalactic medium. Finally, we extrapolate the LAE LF to z ∼ 9 using our model and show that it is unlikely that large area surveys, like UltraVISTA or Euclid, pick up LAEs at this redshift assuming the current depths and area. [ABSTRACT FROM AUTHOR]

The use of submillimeter 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 submillimeter galaxies. All of these objects suggest a similar calibration, strongly supporting the view that the Rayleigh-Jeans tail of the dust emission can be used as an accurate and very fast probe of the interstellar medium (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* ≃ 1011M☼: 37 at z ∼ 0.4, 33 at z ∼ 0.9, and 31 at z = 2. A fourth sample with six infrared-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 by a factor ∼6 from 1 to 2 × 1010M☼ at both z = 2 and 0.9 down to ∼2 × 109M☼ at z = 0.4. The infrared-luminous sample at z = 2 shows a further ∼4 times increase in MISM compared with the equivalent non-infrared-bright sample at the same redshift. The gas mass fractions are ∼2% ± 0.5%, 12% ± 3%, 14% ± 2%, and 53% ± 3% for the four subsamples (z = 0.4, 0.9, and 2 and infrared-bright galaxies). [ABSTRACT FROM AUTHOR]

We present the result of our low-luminosity quasar survey in the redshift range of 4.5 ≲ z ≲ 5.5 in the COSMOS field. Using the COSMOS photometric catalog, we selected 15 quasar candidates with 22 < i′ < 24 at z ∼ 5 that are ∼3 mag fainter than the Sloan Digital Sky Survey quasars in the same redshift range. We obtained optical spectra for 14 of the 15 candidates using FOCAS on the Subaru Telescope and did not identify any low-luminosity type-1 quasars at z ∼ 5, while a low-luminosity type-2 quasar at z ∼ 5.07 was discovered. In order to constrain the faint end of the quasar luminosity function at z ∼ 5, we calculated the 1σ confidence upper limits of the space density of type-1 quasars. As a result, the 1σ confidence upper limits on the quasar space density are Φ < 1.33 × 10–7 Mpc–3 mag–1 for –24.52 < M1450 < –23.52 and Φ < 2.88 × 10–7 Mpc–3 mag–1 for –23.52 < M1450 < –22.52. The inferred 1σ confidence upper limits of the space density are then used to provide constraints on the faint-end slope and the break absolute magnitude of the quasar luminosity function at z ∼ 5. We find that the quasar space density decreases gradually as a function of redshift at low luminosity (M1450 ∼ –23), being similar to the trend found for quasars with high luminosity (M1450 < –26). This result is consistent with the so-called downsizing evolution of quasars seen at lower redshifts. [ABSTRACT FROM AUTHOR]

We investigate the high-redshift quasar luminosity function (QLF) down to an apparent magnitude of IAB = 25 in the Cosmic Evolution Survey (COSMOS). Careful analysis of the extensive COSMOS photometry and imaging data allows us to identify and remove stellar and low-redshift contaminants, enabling a selection that is nearly complete for type-1 quasars at the redshifts of interest. We find 155 likely quasars at z > 3.1, 39 of which have prior spectroscopic confirmation. We present our sample in detail and use these confirmed and likely quasars to compute the rest-frame UV QLF in the redshift bins 3.1 < z < 3.5 and 3.5 < z < 5. The space density of faint quasars decreases by roughly a factor of four from z ∼ 3.2 to z ∼ 4, with faint-end slopes of β ∼ –1.7 at both redshifts. The decline in space density of faint optical quasars at z > 3 is similar to what has been found for more luminous optical and X-ray quasars. We compare the rest-frame UV luminosity functions found here with the X-ray luminosity function at z > 3, and find that they evolve similarly between z ∼ 3.2 and z ∼ 4; however, the different normalizations imply that roughly 75% of X-ray bright active galactic nuclei (AGNs) at z ∼ 3-4 are optically obscured. This fraction is higher than found at lower redshift and may imply that the obscured, type-2 fraction continues to increase with redshift at least to z ∼ 4. Finally, the implications of the results derived here for the contribution of quasars to cosmic reionization are discussed. [ABSTRACT FROM AUTHOR]

We present high-resolution maps of stars, dust, and molecular gas in a strongly lensed submillimeter galaxy (SMG) at z = 3.259. HATLAS J114637.9–001132 is selected from the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) as a strong lens candidate mainly based on its unusually high 500 μm flux density (∼300 mJy). It is the only high-redshift Planck detection in the 130 deg2 H-ATLAS Phase-I area. Keck Adaptive Optics images reveal a quadruply imaged galaxy in the K band while the Submillimeter Array and the Jansky Very Large Array show doubly imaged 880 μm and CO(1→0) sources, indicating differentiated distributions of the various components in the galaxy. In the source plane, the stars reside in three major kpc-scale clumps extended over ∼1.6 kpc, the dust in a compact (∼1 kpc) region ∼3 kpc north of the stars, and the cold molecular gas in an extended (∼7 kpc) disk ∼5 kpc northeast of the stars. The emissions from the stars, dust, and gas are magnified by ∼17, ∼8, and ∼7 times, respectively, by four lensing galaxies at z ∼ 1. Intrinsically, the lensed galaxy is a warm (Tdust ∼ 40-65 K), hyper-luminous (LIR ∼ 1.7 × 1013L☼; star formation rate (SFR) ∼2000 M☼ yr–1), gas-rich (Mgas/Mbaryon ∼ 70%), young (Mstellar/SFR ∼ 20 Myr), and short-lived (Mgas/SFR ∼ 40 Myr) starburst. With physical properties similar to unlensed z > 2 SMGs, HATLAS J114637.9–001132 offers a detailed view of a typical SMG through a powerful cosmic microscope. [ABSTRACT FROM AUTHOR]