Using the far-infrared data obtained by the Herschel Space Observatory, we study the relation between the infrared luminosity (L_IR) and the dust temperature (T) of dusty starbursting galaxies at high redshifts (high-z). We focus on the total infrared luminosity from the cold-dust component (L_IR^(cd)), whose emission can be described by a modified black body (MBB) of a single temperature (T_mbb). An object on the (L_IR^(cd), T_mbb) plane can be explained by the equivalent of the Stefan-Boltzmann law for a MBB with an effective radius of R_eff. We show that R_eff is a good measure of the combined size of the dusty starbursting regions (DSBRs) of the host galaxy. In at least one case where the individual DSBRs are well resolved through strong gravitational lensing, R_eff is consistent with the direct size measurement. We show that the observed L_IR-T relation is simply due to the limited R_eff (<~ 2 kpc). The small R_eff values also agree with the compact sizes of the DSBRs seen in the local universe. However, previous interferometric observations to resolve high-z dusty starbursting galaxies often quote much larger sizes. This inconsistency can be reconciled by the blending effect when considering that the current interferometry might still not be of sufficient resolution. From R_eff we infer the lower limits to the volume densities of the star formation rate ("minSFR3D") in the DSBRs, and find that the $L_{IR}$-$T$ relation outlines a boundary on the (L_IR^(cd), T) plane, below which is the "zone of avoidance" in terms of minSFR3D.
We model the intensity of emission lines from the CO molecule, based on hydrodynamic simulations of spirals, mergers, and high-redshift galaxies with very high resolutions (3pc and 10^3 Msun) and detailed models for the phase-space structure of the interstellar gas including shock heating, stellar feedback processes and galactic winds. The simulations are analyzed with a Large Velocity Gradient (LVG) model to compute the local emission in various molecular lines in each resolution element, radiation transfer and opacity effects, and the intensity emerging from galaxies, to generate synthetic s…
We present the results of combined deep Keck/NIRC2, HST/WFC3 near-infrared and Herschel far infrared observations of an extremely star forming dusty lensed galaxy identified from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS J133542.9+300401). The galaxy is gravitationally lensed by a massive WISE identified galaxy cluster at $z\sim1$. The lensed galaxy is spectroscopically confirmed at $z=2.685$ from detection of $\rm {CO (1 \rightarrow 0)}$ by GBT and from detection of $\rm {CO (3 \rightarrow 2)}$ obtained with CARMA. We use the combined spectroscopic and imaging observatio…
We present SCUBA-2 850-$μ$m observations of 13 candidate starbursting protoclusters selected using Planck and Herschel data. The cumulative number counts of the 850-$μ$m sources in 9/13 of these candidate protoclusters show significant overdensities compared to the field, with the probability $<$10$^{-2}$ assuming the sources are randomly distributed in the sky. Using the 250-, 350-, 500- and 850-$μ$m flux densities, we estimate the photometric redshifts of individual SCUBA-2 sources by fitting spectral energy distribution (SED) templates with an MCMC method. The photometric redshift distribut…
Our current understanding of galaxy evolution still has many uncertainties associated with the details of accretion, processing, and removal of gas across cosmic time. The next generation of radio telescopes will image the neutral hydrogen (HI) in galaxies over large volumes at high redshifts, which will provide key insights into these processes. We are conducting the COSMOS HI Large Extragalactic Survey (CHILES) with the Karl G. Jansky Very Large Array, which is the first survey to simultaneously observe HI from z=0 to z~0.5. Here, we report the highest redshift HI 21-cm detection in emission…
We present a comprehensive study of an unbiased sample of 150 nearby (<z> = 0.014) core-collapse supernova (CCSN) host galaxies drawn from the All-Sky Automated Survey for Supernovae (ASAS-SN) for direct comparison to the nearest LGRB and SLSN hosts. We use public imaging surveys to gather multi-wavelength photometry for all CCSN host galaxies and fit their spectral energy distributions (SEDs) to derive stellar masses and integrated star formation rates. CCSNe populate galaxies across a wide range of stellar masses, from blue and compact dwarf galaxies to large spiral galaxies. We find 33(+4,-…
We investigate the star-forming properties of 1620 X-ray selected AGN host galaxies as a function of their specific X-ray luminosity (i.e., X-ray luminosity per unit host stellar mass) -- a proxy of the Eddington ratio. Our motivation is to determine whether there is any evidence of a suppression of star-formation at high Eddington ratios, which may hint toward "AGN feedback" effects. Star-formation rates (SFRs) are derived from fits to Herschel-measured far-infrared spectral energy distributions, taking into account any contamination from the AGN. Herschel-undetected AGNs are included via sta…
We interpret the large variety of redshift distributions of galaxies found by far-infrared and (sub-)millimeter deep surveys depending on their depth and wavelength using the Béthermin et al. (2012) phenomenological model of galaxy evolution. This model reproduces without any new parameter tuning the observed redshift distributions from 100 $μ$m to 1.4 mm, and especially the increase of the median redshift with survey wavelength. This median redshift varies also significantly with the depth of the surveys, and deeper surveys do necessarily not probe higher redshifts. Paradoxically, at fixed wa…
We present a comparison of the physical properties of a rest-frame $250μ$m selected sample of massive, dusty galaxies from $0<z<5.3$. Our sample comprises 29 high-redshift submillimetre galaxies (SMGs) from the literature, and 843 dusty galaxies at $z<0.5$ from the Herschel-ATLAS, selected to have a similar stellar mass to the SMGs. The $z>1$ SMGs have an average SFR of $390^{+80}_{-70}\,$M$_\odot$yr$^{-1}$ which is 120 times that of the low-redshift sample matched in stellar mass to the SMGs (SFR$=3.3\pm{0.2}$ M$_\odot$yr$^{-1}$). The SMGs harbour a substantial mass of dust ($1.2^{+0.3}_{-0.2…
Far-infrared and submillimeter wavelength surveys have now established the important role of dusty, star-forming galaxies (DSFGs) in the assembly of stellar mass and the evolution of massive galaxies in the Universe. The brightest of these galaxies have infrared luminosities in excess of 10$^{13}$ L$_{\odot}$ with implied star-formation rates of thousands of solar masses per year. They represent the most intense starbursts in the Universe, yet many are completely optically obscured. Their easy detection at submm wavelengths is due to dust heated by ultraviolet radiation of newly forming stars.…
We report Atacama Large Millimetre Array (ALMA) observations of four high-redshift dusty star-forming galaxy candidates selected from far-Infrared (FIR)/submm observations in the COSMOS field. We securely detect all galaxies in the continuum and spectroscopically confirm them at z=3.62--5.85 using ALMA 3mm line scans, detecting multiple CO and/or [CI] transitions. This includes the most distant dusty galaxy currently known in the COSMOS field, ID85001929 at z=5.847. These redshifts are lower than we had expected as these galaxies have substantially colder dust temperatures (i.e., their SEDs pe…
Using NOEMA and ALMA 3mm line scans, we measure spectroscopic redshifts of six new dusty galaxies at 3.5<z<4.2 by solidly detecting [CI](1-0) and CO transitions. The sample was selected from the COSMOS and GOODS-North super-deblended catalogs with FIR photometric redshifts z>6, based on template IR spectrum energy distribution (SED) from known submillimeter galaxies at z=4--6. Dust SED analyses explain the photo-z overestimate from seemingly cold dust temperatures (Td) and steep Rayleigh-Jeans (RJ) slopes, providing additional examples of cold dusty galaxies impacted by the Cosmic Microwave Ba…
Observations suggest that high-redshift galaxies are either very dusty or essentially dust free. The evolution from one regime to the other must also be very fast, since evolved and dusty galaxies show up at redshifts corresponding to a Universe which is only about 500 Myr old. In the present paper models which predicts the existence of an apparent dichotomy between dusty and dust-free galaxies at high redshift are considered. Galaxies become dusty as soon as they reach an evolved state and the transition is very rapid. A special case suggests that while stellar dust production is overall rela…
We show that the use of red colour as the basis for selecting candidate high redshift dusty galaxies from surveys made with Herschel has proved highly successful. The highest redshift such object, HFLS3, lies at z=6.34 and numerous other sources have been found. Spectroscopic followup confirms that most of these lie at z>4. These sources are found in such numbers that they represent a challenge to current models of galaxy evolution. We also examine the prospects for finding dusty galaxies at still higher redshifts. These would not appear in the SPIRE surveys from Herschel but would be detected…
We exploit the continuity equation approach and the `main sequence' star-formation timescales to show that the observed high abundance of galaxies with stellar masses > a few 10^10 M_sun at redshift z>4 implies the existence of a galaxy population featuring large star formation rates (SFRs) > 10^2 M_sun/yr in heavily dust-obscured conditions. These galaxies constitute the high-redshift counterparts of the dusty star-forming population already surveyed for z<3 in the far-IR band by the Herschel space observatory. We work out specific predictions for the evolution of the corresponding stellar ma…
We present the average rest-frame spectrum of high-redshift dusty, star-forming galaxies from 250-770GHz. This spectrum was constructed by stacking ALMA 3mm spectra of 22 such sources discovered by the South Pole Telescope and spanning z=2.0-5.7. In addition to multiple bright spectral features of 12CO, [CI], and H2O, we also detect several faint transitions of 13CO, HCN, HNC, HCO+, and CN, and use the observed line strengths to characterize the typical properties of the interstellar medium of these high-redshift starburst galaxies. We find that the 13CO brightness in these objects is comparab…
In the last decade, it has become clear that the dust-enshrouded star formation contributes significantly to early galaxy evolution. Detection of dust is therefore essential in determining the properties of galaxies in the high-redshift universe. This requires observations at the (sub-)millimeter wavelengths. Unfortunately, sensitivity and background confusion of single dish observations on the one hand, and mapping efficiency of interferometers on the other hand, pose unique challenges to observers. One promising route to overcome these difficulties is intensity mapping of fluctuations which …
We present a feasibility study for the high-redshift galaxy part of the Science Verification Campaign with the 220-440 GHz DESHIMA 2.0 integrated superconducting spectrometer on the ASTE telescope. The first version of the DESHIMA 2.0 chip has been recently manufactured and tested in the lab. Based on these realistic performance measurements, we evaluate potential target samples and prospects for detecting the [CII] and CO emission lines. The planned observations comprise two distinct, but complementary objectives: (1) acquiring spectroscopic redshifts for dusty galaxies selected in far-infrar…
Using the UltraVISTA DR1 and 3D-HST catalogs, we construct a stellar-mass-complete sample, unique for its combination of surveyed volume and depth, to study the evolution of the fractions of quiescent galaxies, moderately unobscured star-forming galaxies, and dusty star-forming galaxies as a function of stellar mass over the redshift interval $0.2 \le z \le 3.0$. We show that the role of dusty star-forming galaxies within the overall galaxy population becomes more important with increasing stellar mass, and grows rapidly with increasing redshift. Specifically, dusty star-forming galaxies domin…
The purported spiral host galaxy of GRB 020819B at z=0.41 has been seminal in establishing our view of the diversity of long-duration gamma-ray burst environments: optical spectroscopy of this host provided evidence that GRBs can form even at high metallicities, while millimetric observations suggested that GRBs may preferentially form in regions with minimal molecular gas. We report new observations from VLT (MUSE and X-shooter) which demonstrate that the purported host is an unrelated foreground galaxy. The probable radio afterglow is coincident with a compact, highly star-forming, dusty gal…
The recent discovery of high redshift dusty galaxies implies a rapid dust enrichment of their interstellar medium (ISM). To interpret these observations, we run a cosmological simulation in a 30$h^{-1}$ cMpc/size volume down to $z \approx 4$. We use the hydrodynamical code dustyGadget, which accounts for the production of dust by stellar populations and its evolution in the ISM. We find that the cosmic dust density parameter ($Ω_{\rm d}$) is mainly driven by stellar dust at $z \gtrsim 10$, so that mass- and metallicity-dependent yields are required to assess the dust content in the first galax…
Until recently, only a handful of dusty, star-forming galaxies (DSFGs) were known at $z>4$, most of them significantly amplified by gravitational lensing. Here, we have increased the number of such DSFGs substantially, selecting galaxies from the uniquely wide 250-, 350- and 500-$μ$m Herschel-ATLAS imaging survey on the basis of their extremely red far-infrared colors and faint 350- and 500-$μ$m flux densities - ergo they are expected to be largely unlensed, luminous, rare and very distant. The addition of ground-based continuum photometry at longer wavelengths from the JCMT and APEX allows us…
Motivated by recent observations suggesting that core-collapse supernovae may on average produce ~0.3 M_sun of dust, we explore a simple dust production scenario which applies to star-forming galaxies in the local environment (the Magellanic Clouds and possibly the Milky Way) as well as to high redshift (sub- millimeter, QSO, Lyman break) galaxies. We assume that the net dust destruction (due to supernova reverse shock, shocks in the interstellar medium, or astration) is negligible on a timescale of 1 Gyr, in which case the dust mass can be estimated as 0.004 times the star-formation rate (for…
Selecting sources with rising flux densities towards longer wavelengths from Herschel/SPIRE maps is an efficient way to produce a catalogue rich in high-redshift (z > 4) dusty star-forming galaxies. The effectiveness of this approach has already been confirmed by spectroscopic follow-up observations, but the previously available catalogues made this way are limited by small survey areas. Here we apply a map-based search method to 274 deg$^2$ of the HerMES Large Mode Survey (HeLMS) and create a catalogue of 477 objects with SPIRE flux densities $S_{500} > S_{350} >S_{250}$ and a $5 σ$ cut-off $…
A complete census of dusty star-forming galaxies (DSFGs) at early epochs is necessary to constrain the obscured contribution to the cosmic star formation rate density (CSFRD), however DSFGs beyond $z \sim 4$ are both rare and hard to identify from photometric data alone due to degeneracies in submillimeter photometry with redshift. Here, we present a pilot study obtaining follow-up Atacama Large Millimeter Array (ALMA) $2\,$mm observations of a complete sample of 39 $850\,\rmμm$-bright dusty galaxies in the SSA22 field. Empirical modeling suggests $2\,$mm imaging of existing samples of DSFGs s…
We report a ground-based detection of the [OI] 63-um line in a z=6.027 gravitationally lensed dusty star-forming galaxy (DSFG) G09.83808 using the APEX SEPIA 660 receiver, the first unambiguous detection of the [OI]63 line beyond redshift 3, and the first obtained from the ground. The [OI]63 line is robustly detected at 22$\pm$5 Jy km s$^{-1}$, corresponding to an intrinsic (de-lensed) luminosity of $(5.4\pm1.3)\times10^{9}$ L$_\odot$. With the [OI]63/[CII] luminosity ratio of 4, the [OI]63 line is the main coolant of the neutral gas in this galaxy, in agreement with model predictions. The hig…
Using the EMIR instrument on the IRAM 30m telescope, we conducted a spectroscopic redshift search of seven z$_{\rm phot}$ $\sim$ 4 sub-millimetre bright galaxies selected from the Herschel Bright Sources (HerBS) sample with fluxes at 500 $μ$m greater than 80 mJy. For four sources, we obtained spectroscopic redshifts between 3.4 < z < 4.1 through the detection of multiple CO-spectral lines with J $\leq$ 3. Later, we detected low-J transitions for two of these sources with the GBT including the CO(1-0) transition. For the remaining three sources, more data are needed to determine the spectroscop…
We report the detection of ADFS-27, a dusty, starbursting major merger at a redshift of z=5.655, using the Atacama Large Millimeter/submillimeter Array (ALMA). ADFS-27 was selected from Herschel/SPIRE and APEX/LABOCA data as an extremely red "870 micron riser" (i.e., S_250<S_350<S_500<S_870), demonstrating the utility of this technique to identify some of the highest-redshift dusty galaxies. A scan of the 3mm atmospheric window with ALMA yields detections of CO(5-4) and CO(6-5) emission, and a tentative detection of H2O(211-202) emission, which provides an unambiguous redshift measurement. The…
We report the discovery of an intrinsically faint, quintuply-imaged, dusty galaxy MACS0600-z6 at a redshift $z=$6.07 viewed through the cluster MACSJ0600.1-2008 ($z$=0.46). A $\simeq4σ$ dust detection is seen at 1.2mm as part of the ALMA Lensing Cluster Survey (ALCS), an on-going ALMA Large program, and the redshift is secured via [C II] 158 $μ$m emission described in a companion paper. In addition, spectroscopic follow-up with GMOS/Gemini-North shows a break in the galaxy's spectrum, consistent with the Lyman break at that redshift. We use a detailed mass model of the cluster and infer a magn…
We use the Atacama Large Millimeter/submillimeter Array (ALMA) in Cycle 1 to determine spectroscopic redshifts of high-redshift dusty star-forming galaxies (DSFGs) selected by their 1.4mm continuum emission in the South Pole Telescope (SPT) survey. We present ALMA 3mm spectral scans between 84-114GHz for 15 galaxies and targeted ALMA 1mm observations for an additional eight sources. Our observations yield 30 new line detections from CO, [CI] , [NII] , H_2O and NH_3. We further present APEX [CII] and CO mid-J observations for seven sources for which only a single line was detected in spectral-s…
We present the results of the analysis of multiwavelength Spectral Energy Distributions (SEDs) of far-infrared galaxies detected in the AKARI Deep Field-South (ADF--S) Survey. The analysis uses a carefully selected sample of 186 sources detected at the 90 $μ$m AKARI band, identified as galaxies with cross-identification in public catalogues. For sources without known spectroscopic redshifts, we estimate photometric redshifts after a test of two independent methods: one based on using mainly the optical -- mid infrared range, and one based on the whole range of ultraviolet -- far infrared data.…
We present ALMA and VLA detections of the dense molecular gas tracers HCN, HCO$^+$ and HNC in two lensed, high-redshift starbursts selected from the {\it Herschel}-ATLAS survey: {\it H}-ATLAS\,J090740.0$-$004200 (SDP.9, $z \sim 1.6$) and {\it H}-ATLAS\,J091043.1$-$000321 (SDP.11, $z \sim 1.8$). ALMA observed the $J = 3-2$ transitions in both sources, while the VLA observed the $J = 1-0$ transitions in SDP.9. We have detected all observed HCN and HCO$^+$ lines in SDP.9 and SDP.11, and also HNC(3--2) in SDP.9. The amplification factors for both galaxies have been determined from sub-arcsec resol…
A Deep ALMA Survey of the Redshift Distribution of Dusty Star-forming Galaxies
University of Wisconsin–Madison（威斯康星大学麦迪逊分校）；University of Hawaii（夏威夷大学）；Institute for Astronomy, University of Hawaii（夏威夷大学天体物理研究所）；Universidad de Tarapacá（塔拉帕卡大学）
Understanding how super-massive black holes form and grow in the early Universe has become a major challenge since the discovery of luminous quasars only 700 million years after the Big Bang. Simulations indicate an evolutionary sequence of dust-reddened quasars emerging from heavily dust-obscured starbursts that then transition to unobscured luminous quasars by expelling gas and dust. Although the last phase has been identified out to a redshift of 7.6, a transitioning quasar has not been found at similar redshifts owing to their faintness at optical and near-infrared wavelengths. Here we rep…
Luminous and ultra-luminous infrared galaxies ((U)LIRGs) are rare today but are increasingly abundant at high redshifts. They are believed to be dusty starbursts, and hence should have high rates of supernovae (multiple events per year). Due to their extremely dusty environment, however, such supernovae could only be detected in restframe infrared and longer wavelengths, where our current facilities lack the capability of finding them individually beyond the local universe. We propose a new technique for higher redshifts, which is to search for the presence of supernovae through the variabilit…
Large photometric surveys provide a rich source of observations of quiescent galaxies, including a surprisingly large population at z>1. However, identifying large, but clean, samples of quiescent galaxies has proven difficult because of their near-degeneracy with interlopers such as dusty, star-forming galaxies. We describe a new technique for selecting quiescent galaxies based upon t-distributed stochastic neighbor embedding (t-SNE), an unsupervised machine learning algorithm for dimensionality reduction. This t-SNE selection provides an improvement both over UVJ, removing interlopers which …
The South Pole Telescope (SPT) has systematically identified 81 high-redshift, strongly gravitationally lensed, dusty star-forming galaxies (DSFGs) in a 2500 square degree cosmological mm-wave survey. We present the final spectroscopic redshift survey of this flux-limited ($S_{870\, \mathrm{μm}} > 25\, \mathrm{mJy}$) sample, initially selected at $1.4$ mm. The redshift survey was conducted with the Atacama Large Millimeter/submillimeter Array across the $3$ mm spectral window, targeting carbon monoxide line emission. By combining these measurements with ancillary data, the SPT sample is now sp…
We study the radio properties of 706 sub-millimeter galaxies (SMGs) selected at 870$μ$m with the Atacama Large Millimeter Array from the SCUBA-2 Cosmology Legacy Survey map of the Ultra Deep Survey field. We detect 273 SMGs at $>4σ$ in deep Karl G. Jansky Very Large Array 1.4 GHz observations, of which a subset of 45 SMGs are additionally detected in 610 MHz Giant Metre-Wave Radio Telescope imaging. We quantify the far-infrared/radio correlation through parameter $q_\text{IR}$, defined as the logarithmic ratio of the far-infrared and radio luminosity, and include the radio-undetected SMGs thro…
We report interferometric imaging of [CII] and OH emission toward the center of the galaxy protocluster associated with the z=5.3 submillimeter galaxy (SMG) AzTEC-3, using the Atacama Large (sub)Millimeter Array (ALMA). We detect strong [CII], OH, and rest-frame 157.7 um continuum emission toward the SMG. The [CII] emission is distributed over a scale of 3.9 kpc, implying a dynamical mass of 9.7 x 10^10 Msun, and a star formation rate (SFR) surface density of Sigma_SFR = 530 Msun/yr/kpc2. This suggests that AzTEC-3 forms stars at Sigma_SFR approaching the Eddington limit for radiation pressure…
We present 1.3- and/or 3-mm continuum images and 3-mm spectral scans, obtained using NOEMA and ALMA, of 21 distant, dusty, star-forming galaxies (DSFGs). Our sample is a subset of the galaxies selected by Ivison et al. (2016) on the basis of their extremely red far-infrared (far-IR) colours and low {\it Herschel} flux densities; most are thus expected to be unlensed, extraordinarily luminous starbursts at $z \gtrsim 4$, modulo the considerable cross-section to gravitational lensing implied by their redshift. We observed 17 of these galaxies with NOEMA and four with ALMA, scanning through the 3…
The discoveries of huge amounts of dust and unusual extinction curves in high-redshift quasars (z > 4) cast challenging issues on the origin and properties of dust in the early universe. In this Letter, we investigate the evolutions of dust content and extinction curve in a high-z quasar, based on the dust evolution model taking account of grain size distribution. First, we show that the Milky-Way extinction curve is reproduced by introducing a moderate fraction (~0.2) of dense molecular-cloud phases in the interstellar medium for a graphite-silicate dust model. Then we show that the peculier …
$\mathit{Herschel}$ extragalactic surveys offer a unique opportunity to efficiently select a significant number of rare and massive dusty objects, and thus gain insight into the prodigious star-forming activity that takes place in the very distant Universe. To search for $z\geq4$ dusty star-forming galaxies, in this work we consider red SPIRE objects with fluxes rising from 250 $μ$m to $500\:μ$m (so-called "500 $μ$m-risers"). We aim to implement a novel method to obtain a statistical sample of "500 $μ$m-risers" and fully evaluate our selection inspecting different models of galaxy evolution. W…
Dusty high-z galaxies are extreme objects with high star formation rates (SFRs) and luminosities. Characterising the properties of this population and analysing their evolution over cosmic time is key to understanding galaxy evolution in the early Universe. We select a sample of high-z dusty star-forming galaxies (DSFGs) and evaluate their position on the main sequence (MS) of star-forming galaxies, the well-known correlation between stellar mass and SFR. We aim to understand the causes of their high star formation and quantify the percentage of DSFGs that lie above the MS. We adopted a multi-…
We present the detailed characterisation of a sample of 56 sources serendipitously detected in ALMA band 7, as part of the ALMA Large Program to INvestigate CII at Early Times (ALPINE) in COSMOS and ECDFS. These sources have been used to derive the total infrared luminosity function (LF) and to estimate the cosmic star formation rate density (SFRD) up to z=6. We have looked for counterparts in all the available multi-wavelength and photometric redshift catalogues, and in deeper near- and mid-IR source lists and maps, to identify optically dark sources with no matches in the public catalogues. …
We present a sub-kpc resolved study of the interstellar medium properties in SDP.81, a z=3.042 strongly gravitationally lensed dusty star-forming galaxy, based on high-resolution, multi-band ALMA observations of the FIR continuum, CO ladder and the [CII] line. Using a visibility-plane lens modelling code, we achieve a median source-plane resolution of ~200 pc. We use photon-dominated region (PDR) models to infer the physical conditions - far-UV field strength, density, and PDR surface temperature - of the star-forming gas on 200-pc scales, finding a FUV field strength of ~10^3-10^4 G0, gas den…
We present a Herschel/SPIRE survey of three protoclusters at z=2-3 (2QZCluster, HS1700, SSA22). Based on the SPIRE colours (S350/S250 and S500/S350) of 250 $μ$m sources, we selected high redshift dusty star-forming galaxies potentially associated with the protoclusters. In the 2QZCluster field, we found a 4-sigma overdensity of six SPIRE sources around 4.5' (~2.2 Mpc) from a density peak of H$α$ emitters at z=2.2. In the HS1700 field, we found a 5-sigma overdensity of eight SPIRE sources around 2.1' (~1.0 Mpc) from a density peak of LBGs at z=2.3. We did not find any significant overdensities …
We present an analysis of the optical-to-near-IR counterparts of a sample of candidate dusty starbursts at z > 6. These objects were pre-selected based on the rising trend of their far-infrared-to-sub-millimeter spectral energy distributions and the fact that they are radio-weak. Their precise positions are available through millimeter and/or radio interferometry, which enable us to search for their counterparts in the deep optical-to-near-IR images. The sample include five z > 6 candidates. Three of them have their counterparts identified, one is still invisible in the deepest images, and one…
We present SCUBA-2 850um submillimetre (submm) observations of the fields of 10 dusty, luminous galaxies at z ~ 1.7 - 4.6, detected at 12um and/or 22um by the WISE all-sky survey, but faint or undetected at 3.4um and 4.6um; dubbed hot, dust-obscured galaxies (Hot DOGs). The six detected targets all have total infrared luminosities greater than 10^13 L_sun, with one greater than 10^14 L_sun. Their spectral energy distributions (SEDs) are very blue from mid-infrared to submm wavelengths and not well fitted by standard AGN SED templates, without adding extra dust extinction to fit the WISE 3.4um …
A mock redshift catalogue of the dusty star-forming galaxy population with intrinsic clustering and lensing for deep millimetre surveys
Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE)（国家天体物理学、光学和电子学研究所）；Universidad Nacional Autónoma de México, Instituto de Astronomía（墨西哥国立自治大学天文研究所）
The bright [CI] 1-0 and [CI] 2-1 lines of atomic carbon are becoming more and more widely employed tracers of the cold neutral gas in high-redshift galaxies. Here we present observations of these lines in the 11 galaxies of the set of Planck's Dusty GEMS, the brightest gravitationally lensed galaxies on the extragalactic submillimeter sky probed by the Planck satellite. We have [CI] 1-0 measurements for seven, and [CI] 2-1 measurements for eight galaxies, including four galaxies where both lines are measured. We use our observations to constrain the gas excitation mechanism, excitation tempera…
The South Pole Telescope has discovered one hundred gravitationally lensed, high-redshift, dusty, star-forming galaxies (DSFGs). We present 0.5" resolution 870um Atacama Large Millimeter/submillimeter Array imaging of a sample of 47 DSFGs spanning z=1.9-5.7, and construct gravitational lens models of these sources. Our visibility-based lens modeling incorporates several sources of residual interferometric calibration uncertainty, allowing us to properly account for noise in the observations. At least 70% of the sources are strongly lensed by foreground galaxies (mu_870um > 2), with a median ma…
Dusty star-forming galaxies (DSFGs) at redshift z$\geq$1 are among the most vigorously star-forming galaxies in the Universe. However, their dense ($\geq$10$^5$ cm$^{-3}$ ) gas phase - typically traced by HCN(1-0) - remains almost entirely unexplored: only two DSFGs have been detected in HCN(1-0) to date. We present results of a JVLA survey of the J=1-0 transition of HCN, HCO+, and HNC(1-0) in six strongly lensed DSFGs at z = 2.5 - 3.3, effectively doubling the number of DSFGs with deep observations of these lines. We detect HCN(1-0) emission in one source (J1202+5354, 4.4$σ$), with a tentativ…
