- ID:
- ivo://CDS.VizieR/J/ApJ/853/172
- Title:
- "Super-deblended" dust emission in galaxies. I.
- Short Name:
- J/ApJ/853/172
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new technique to measure multi-wavelength "super-deblended" photometry from highly confused images, which we apply to Herschel and ground-based far-infrared (FIR) and (sub-)millimeter (mm) data in the northern field of the Great Observatories Origins Deep Survey (GOODS-N). There are two key novelties. First, starting with a large database of deep Spitzer 24{mu}m and VLA 20cm detections that are used to define prior positions for fitting the FIR/submm data, we perform an active selection of useful priors independently at each frequency band, moving from less to more confused bands. Exploiting knowledge of redshift and all available photometry, we identify hopelessly faint priors that we remove from the fitting pool. This approach significantly reduces blending degeneracies and allows reliable photometry to be obtained for galaxies in FIR+mm bands. Second, we obtain well-behaved, nearly Gaussian flux density uncertainties, individually tailored to all fitted priors for each band. This is done by exploiting extensive simulations that allow us to calibrate the conversion of formal fitting uncertainties to realistic uncertainties, depending on directly measurable quantities. We achieve deeper detection limits with high fidelity measurements and uncertainties at FIR+mm bands. As an illustration of the utility of these measurements, we identify 70 galaxies with z>=3 and reliable FIR+mm detections. We present new constraints on the cosmic star formation rate density at 3<z<6, finding a significant contribution from z>=3 dusty galaxies that are missed by optical-to-near-infrared color selection. Photometric measurements for 3306 priors, including more than 1000 FIR+mm detections, are released publicly with our catalog.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/865/106
- Title:
- SUPER GOODS. III. ALMA data for SCUBA-2 sources
- Short Name:
- J/ApJ/865/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the >4{sigma} sources in the most sensitive 100arcmin^2^ area (rms<0.56mJy) of a SCUBA-2 850{mu}m survey of the GOODS-S and present the 75 band-7 ALMA sources (>4.5{sigma}) obtained from high-resolution interferometric follow-up observations. The raw SCUBA-2 >4{sigma} limit is fainter than 2.25mJy throughout this region, and deboosting corrections would lower this further. Of the 53 SCUBA-2 sources in this sample, only five have no ALMA detections, while 13% (68% confidence range 7%-19%) have multiple ALMA counterparts. Color-based high-redshift dusty galaxy selection techniques find at most 55% of the total ALMA sample. In addition to using literature spectroscopic and optical/near-infrared photometric redshifts, we estimate far infrared photometric redshifts based on an Arp 220 template. We identify seven z>~4 candidates. We see the expected decline with redshift of the 4.5 and 24{mu}m to 850{mu}m flux ratios, confirming these as good diagnostics of z>~4 candidates. We visually classify 52 ALMA sources, finding 44% (68% confidence range 35%-53%) to be apparent mergers. We calculate rest-frame 2-8keV and 8-28keV luminosities using the 7Ms Chandra X-ray image. Nearly all of the ALMA sources detected at 0.5-2keV are consistent with a known X-ray luminosity to 850{mu}m flux relation for star-forming galaxies, while most of those detected at 2-7keV are moderate-luminosity AGNs that lie just above the 2-7keV detection threshold. The latter largely have substantial obscurations of logN_H_=23-24cm^-2^, but two of the high-redshift candidates may even be Compton thick.
- ID:
- ivo://CDS.VizieR/J/ApJ/837/139
- Title:
- SUPER GOODS. I. Ultradeep SCUBA-2 survey
- Short Name:
- J/ApJ/837/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this first paper in the SUPER GOODS series on powerfully star-forming galaxies in the two GOODS fields, we present a deep SCUBA-2 survey of the GOODS-N at both 850 and 450{mu}m (central rms noise of 0.28mJy and 2.6mJy, respectively). In the central region, the 850{mu}m observations cover the GOODS-N to near the confusion limit of ~1.65mJy, while over a wider 450arcmin^2^ region-well complemented by Herschel far-infrared imaging-they have a median 4{sigma} limit of 3.5mJy. We present >=4{sigma} catalogs of 186 850{mu}m and 31 450{mu}m selected sources. We use interferometric observations from the Submillimeter Array (SMA) and the Karl G. Jansky Very Large Array (VLA) to obtain precise positions for 114 SCUBA-2 sources (28 from the SMA, all of which are also VLA sources). We present new spectroscopic redshifts and include all existing spectroscopic or photometric redshifts. We also compare redshifts estimated using the 20cm/850{mu}m and the 250cm/850{mu}m flux ratios. We show that the redshift distribution increases with increasing flux, and we parameterize the dependence. We compute the star formation history and the star formation rate (SFR) density distribution functions in various redshift intervals, finding that they reach a peak at z=2-3 before dropping to higher redshifts. We show that the number density per unit volume of SFR>~500M_{sun}_/yr galaxies measured from the SCUBA-2 sample does not change much relative to that of lower SFR galaxies from UV selected samples over z=2-5, suggesting that, apart from changes in the normalization, the shape in the number density as a function of SFR is invariant over this redshift interval.
- ID:
- ivo://CDS.VizieR/J/ApJ/887/23
- Title:
- SUPER GOODS. IV. 850um data of CDFS X-ray sources
- Short Name:
- J/ApJ/887/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Chandra Deep Field (CDF)-S is the deepest X-ray image available and will remain so for the near future. We provide a spectroscopic (64.5%; 64% with spectral classifications) and photometric redshift catalog for the full 7Ms sample, but much of our analysis focuses on the central (off-axis angles <5.7') region, which contains a large, faint ALMA sample of 75 >4.5{sigma} 850{mu}m sources. We measure the 850{mu}m fluxes at the X-ray positions using the ALMA images, where available, or an ultradeep SCUBA-2 map. We find that the full X-ray sample produces ~10% of the 850{mu}m extragalactic background light. We separate the submillimeter-detected X-ray sources into star-forming galaxies and active galactic nuclei (AGNs) using a star formation rate (SFR) versus X-ray luminosity calibration for high-SFR galaxies. We confirm this separation using the X-ray photon indices. We measure the X-ray fluxes at the accurate positions of the 75 ALMA sources and detect 70% at >3{sigma} in either the 0.5-2 or 2-7keV bands. However, many of these may produce both their X-ray and submillimeter emission by star formation. Indeed, we find that only 20% of the ALMA sources have intermediate X-ray luminosities (rest-frame 8-28 keV luminosities of 10^42.5^-10^44^erg/s), and none has a high X-ray luminosity (>10^44^erg/s). Conversely, after combining the CDF-S with the CDF-N, we find extreme star formation (SFR>300M_{sun}_/yr) in some intermediate X-ray luminosity sources but not in any high X-ray luminosity sources. We argue that the quenching of star formation in the most luminous AGNs may be a consequence of the clearing of gas in these sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/872/158
- Title:
- Survey of Class II sources in Taurus with ALMA
- Short Name:
- J/ApJ/872/158
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted a survey of young single and multiple systems in the Taurus-Auriga star-forming region with the Atacama Large Millimeter Array (ALMA), substantially improving both the spatial resolution and sensitivity with which individual protoplanetary disks in these systems have been observed. These ALMA observations can resolve binary separations as small as 25-30au and have an average 3{sigma} detection level of 0.35mJy, equivalent to a disk mass of 4x10^-5^M_{sun}_ for an M3 star. Our sample was constructed from stars that have an infrared excess and/or signs of accretion and have been classified as Class II. For the binary and higher-order multiple systems observed, we detect {lambda}=1.3mm continuum emission from one or more stars in all of our target systems. Combined with previous surveys of Taurus, our 21 new detections increase the fraction of millimeter-detected disks to over 75% in all categories of stars (singles, primaries, and companions) earlier than spectral type M6 in the Class II sample. Given the wealth of other information available for these stars, this has allowed us to study the impact of multiplicity with a much larger sample. While millimeter flux and disk mass are related to stellar mass as seen in previous studies, we find that both primary and secondary stars in binary systems with separations of 30-4200au have lower values of millimeter flux as a function of stellar mass than single stars. We also find that for these systems, the circumstellar disk around the primary star does not dominate the total disk mass in the system and contains on average 62% of the total mass.
- ID:
- ivo://CDS.VizieR/J/ApJS/253/44
- Title:
- Survey of SiO maser emission in oxygen-rich stars
- Short Name:
- J/ApJS/253/44
- Date:
- 01 Mar 2022 00:16:35
- Publisher:
- CDS
- Description:
- Circumstellar environments of oxygen-rich stars are among the strongest SiO maser emitters. Physical processes such as collisions, infrared pumping, and overlaps favor the inversion of level population and produce maser emission at different vibrational states. Despite numerous observational and theoretical efforts, we still do not have a unified picture including all of the physical processes involved in SiO maser emission. The aim of this work is to provide homogeneous data in a large sample of oxygen-rich stars. We present a survey of 67 oxygen-rich stars from 7 to 1mm, in their rotational transitions from J=1-0 to J=5-4, for vibrational numbers v from 0 to 6 in the three main SiO isotopologs. We have used one of the 34 m NASA antennas at Robledo and the IRAM 30m radio telescope. The first tentative detection of a v=6 line is reported, as well as the detection of new maser lines. The highest vibrational levels seem confined to small volumes, presumably close to the stars. The J=1-0, v=2 line flux is greater than the corresponding v=1 in almost half of the sample, which may confirm a predicted dependence on the pulsation cycle. This database is potentially useful in models which should consider most of the physical agents, time dependency, and mass-loss rates. As a by-product, we report detections of 27 thermal rotational lines from other molecules, including isotopologs of SiS, H_2_S, SO, SO_2_, and NaCl.
- ID:
- ivo://CDS.VizieR/J/A+A/654/A52
- Title:
- SVS13-A Class I IRAM-NOEMA images
- Short Name:
- J/A+A/654/A52
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Recent results in astrochemistry have revealed that some molecules, such as interstellar complex organic species and deuterated species, can serve as valuable tools in the investigation of star-forming regions. Sulphuretted species can also be used to follow the chemical evolution of the early stages of a Sun-like star formation process. The goal is to obtain a census of S-bearing species using interferometric images towards SVS13-A, a Class I object associated with a hot corino that is rich in interstellar complex organic molecules. To this end, we used the NGC1333 SVS13-A data at 3mm and 1.4mm obtained with the IRAM-NOEMA interferometer in the framework of the SOLIS (Seeds of Life in Space) Large Program. The line emission of S-bearing species was imaged and analyzed using local thermodynamic equilibrium (LTE) and large velocity gradient (LVG) approaches. We imaged the spatial distribution on <=300au scale of the line emission of ^32^SO, ^34^SO, C^32^S, C^34^S, C^33^S, OCS, H_2_C^32^S, H_2_C^34^S, and NS. The low excitation (9K) ^32^SO line traces: (i) the low-velocity SVS13-A outflow and (ii) the fast (up to 100km/s away from the systemic velocity) collimated jet driven by the nearby SVS13-B Class 0 object. Conversely, the rest of the lines are confined in the inner SVS13-A region, where complex organics were previously imaged.More specifically, the non-LTE LVG analysis of SO, SO_2_, and H_2_CS indicates a hot corino origin (size in the 60-120au range). Temperatures between 50K and 300K, as well as volume densities larger than 10^5^cm^-3^ have been derived. The abundances of the sulphuretted are in the following ranges: 0.3-6x10^-6^ (CS), 7x10^-9^-1x10^-7^ (SO), 1-10x10^-7^ (SO_2_), a few 10^-10^ (H_2_CS and OCS), and 10^-10^-10^-9^ (NS). The N(NS)/N(NS+) ratio is larger than 10, supporting the assessment that the NS+ ion is mainly formed in the extended envelope. The [H_2_CS]/[H_2_CO] ratio, once measured at high-spatial resolutions, increases with time (from Class 0 to Class II objects) by more than one order of magnitude (from <=10^-2^ to a few 10^-1^). This suggests that [S]/[O] changes along the process of Sun-like star formation. Finally, the estimate of the [S]/[H] budget in SVS13-A is 2%-17% of the Solar System value (1.8x10^-5^), which is consistent with what was previously measured towards Class 0 objects (1%-8%). This finding supports the notion that the enrichment of the sulphuretted species with respect to dark clouds remains constant from the Class 0 to the Class I stages of lowmass star formation. The present findings stress the importance of investigating the chemistry of star-forming regions using large observational surveys as well as sampling regions on the scale of the Solar System.
- ID:
- ivo://CDS.VizieR/J/MNRAS/424/1636
- Title:
- Swift/UVOT sources in NGC4321 (M100)
- Short Name:
- J/MNRAS/424/1636
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the star-forming regions in the spiral galaxy NGC 4321 (M100). We take advantage of the spatial resolution (2.5-arcsec full width at half-maximum) of the Swift/Ultraviolet/Optical Telescope camera and the availability of three ultraviolet (UV) passbands in the region 1600<{lambda}<3000{AA}, in combination with optical and infrared (IR) imaging from Sloan Digital Sky Survey, KPNO/H{alpha} and Spitzer/IRAC, to obtain a catalogue of 787 star-forming regions out to three disc scalelengths. We use a large volume of star formation histories, combined with stellar population synthesis, to determine the properties of the young stellar component and its relationship with the spiral arms.
- ID:
- ivo://CDS.VizieR/J/AJ/155/54
- Title:
- TBOSS Survey. II. ALMA continuum observations
- Short Name:
- J/AJ/155/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 885 {mu}m ALMA continuum flux densities for 24 Taurus members spanning the stellar/substellar boundary with spectral types from M4 to M7.75. Of the 24 systems, 22 are detected at levels ranging from 1.0 to 55.7 mJy. The two nondetections are transition disks, though other transition disks in the sample are detected. Converting ALMA continuum measurements to masses using standard scaling laws and radiative transfer modeling yields dust mass estimates ranging from ~0.3 to 20 M_{Earth}_. The dust mass shows a declining trend with central object mass when combined with results from submillimeter surveys of more massive Taurus members. The substellar disks appear as part of a continuous sequence and not a distinct population. Compared to older Upper Sco members with similar masses across the substellar limit, the Taurus disks are brighter and more massive. Both Taurus and Upper Sco populations are consistent with an approximately linear relationship in M_dust_ to M_star_, although derived power-law slopes depend strongly upon choices of stellar evolutionary model and dust temperature relation. The median disk around early-M stars in Taurus contains a comparable amount of mass in small solids as the average amount of heavy elements in Kepler planetary systems on short-period orbits around M-dwarf stars, with an order of magnitude spread in disk dust mass about the median value. Assuming a gas-to-dust ratio of 100:1, only a small number of low-mass stars and brown dwarfs have a total disk mass amenable to giant planet formation, consistent with the low frequency of giant planets orbiting M dwarfs.
- ID:
- ivo://CDS.VizieR/J/ApJ/626/L15
- Title:
- Templates for photometric redshifts of submm sources
- Short Name:
- J/ApJ/626/L15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There is growing evidence that some star-forming galaxies at z>1 are characterized by high efficiencies and specific star formation rates. In the local universe, these traits are shared by "active" blue compact dwarf galaxies (BCDs) with compact and dense star-forming regions. The spectral energy distributions (SEDs) of these BCDs are dominated by young massive star clusters, embedded in a cocoon of dust. In this Letter, we incorporate these BCD SEDs as templates for two samples of high-redshift galaxy populations selected at submillimeter wavelengths.
