- ID:
- ivo://CDS.VizieR/J/MNRAS/370/1057
- Title:
- Blank-field SCUBA surveys
- Short Name:
- J/MNRAS/370/1057
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Since the advent of Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT), a series of complementary surveys has resolved the bulk of the far-infrared extragalactic background into discrete sources. This has revealed a population of heavily dust-obscured sources at high redshift (z>1) undergoing an intense period of massive star-forming activity with inferred star formation rates of several hundred to several thousand solar masses per year. Taken together, these existing surveys cover a total area of 460arcmin^2^ to a range of depths, but combining the results has hitherto been complicated by the fact that different survey groups have used different methods of data reduction and source extraction. In this paper, we re-reduce and re-analyse all of the blank-field surveys to date in an almost identical manner to that employed in the 'SCUBA 8-mJy Survey'. Comparative source catalogues are given which include a number of new significant source detections as well as failing to confirm some of those objects previously published. These new source catalogues have been combined to produce the most accurate number counts to date from 2 to 12.5mJy.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/727/114
- Title:
- BLAST 2005: a 10deg^2^ survey in Cygnus X
- Short Name:
- J/ApJ/727/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Cygnus X in a new multi-wavelength perspective based on an unbiased BLAST survey at 250, 350, and 500um, combined with rich data sets for this well-studied region. Our primary goal is to investigate the early stages of high-mass star formation. We have detected 184 compact sources in various stages of evolution across all three BLAST bands. From their well-constrained spectral energy distributions, we obtain the physical properties mass, surface density, bolometric luminosity, and dust temperature. Some of the bright sources reaching 40K contain well-known compact HII regions. We relate these to other sources at earlier stages of evolution via the energetics as deduced from their position in the luminosity-mass (L-M) diagram. The BLAST spectral coverage, near the peak of the spectral energy distribution of the dust, reveals fainter sources too cool (~10K) to be seen by earlier shorter-wavelength surveys like IRAS. We detect thermal emission from infrared dark clouds and investigate the phenomenon of cold "starless cores" more generally. Spitzer images of these cold sources often show stellar nurseries, but these potential sites for massive star formation are "starless" in the sense that to date there is no massive protostar in a vigorous accretion phase.
- ID:
- ivo://CDS.VizieR/J/A+A/543/A65
- Title:
- BLAST line survey toward Vela-D cloud
- Short Name:
- J/A+A/543/A65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Starless cores represent a very early stage of the star formation process, before collapse results in the formation of a central protostar or a multiple system of protostars. We use spectral line observations of a sample of cold dust cores, previously detected with the BLAST telescope in the Vela-D molecular cloud, to perform a more accurate physical and kinematical analysis of the sources. We present a 3-mm and 1.3-cm survey conducted with the Mopra 22-m and Parkes 64-m radio telescopes of a sample of 40 cold dust cores, including both starless and proto-stellar sources. 20 objects were also mapped using molecular tracers of dense gas. To trace the dense gas we used the molecular species NH3, N2H+, HNC, HCO+, H13CO+, HCN and H13CN, where some of them trace the more quiescent gas, while others are sensitive to more dynamical processes. The selected cores have a wide variety of morphological types and also show physical and chemical variations, which may be associated to different evolutionary phases. We find evidence of systematic motions in both starless and proto-stellar cores and we detect line wings in many of the proto-stellar cores. Our observations probe linear distances in the sources <~0.1pc, and are thus sensitive mainly to molecular gas in the envelope of the cores. In this region we do find that, for example, the radial profile of the N2H+(1-0) emission falls off more quickly than that of C-bearing molecules such as HNC(1-0), HCO+(1-0) and HCN(1-0). We also analyze the correlation between several physical and chemical parameters and the dynamics of the cores. Depending on the assumptions made to estimate the virial mass, we find that many starless cores have masses below the self-gravitating threshold, whereas most of the proto-stellar cores have masses which are near or above the self-gravitating critical value. An analysis of the median properties of the starless and proto-stellar cores suggests that the transition from the pre- to the proto-stellar phase is relatively fast, leaving the core envelopes with almost unchanged physical parameters.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/222
- Title:
- BLAST observations of the SEP field
- Short Name:
- J/ApJS/191/222
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey carried out by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) on a 9deg^2^ field near the South Ecliptic Pole at 250, 350, and 500um. The median 1{sigma} depths of the maps are 36.0, 26.4, and 18.4mJy, respectively. We apply a statistical method to estimate submillimeter galaxy number counts and find that they are in agreement with other measurements made with the same instrument and with the more recent results from Herschel/SPIRE. Thanks to the large field observed, the new measurements give additional constraints on the bright end of the counts. We identify 132, 89, and 61 sources with S/N>=4 at 250, 350, 500um, respectively and provide a multi-wavelength combined catalog of 232 sources with a significance >=4{sigma} in at least one BLAST band.
- ID:
- ivo://CDS.VizieR/J/other/Nat/458.737
- Title:
- BLAST sources at 250, 350 and 500um
- Short Name:
- J/other/Nat/458.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Submillimetre surveys during the past decade have discovered a population of luminous, high-redshift, dusty starburst galaxies. In the redshift range 1 less than or equal to z less than or equal to 4, these massive submillimetre galaxies go through a phase characterized by optically obscured star formation at rates several hundred times that in the local Universe. Half of the starlight from this highly energetic process is absorbed and thermally re-radiated by clouds of dust at temperatures near 30K with spectral energy distributions peaking at 100um in the rest frame. At 1 less than or equal to z less than or equal to 4, the peak is redshifted to wavelengths between 200 and 500um. The cumulative effect of these galaxies is to yield extragalactic optical and far-infrared backgrounds with approximately equal energy densities. Since the initial detection of the far-infrared background (FIRB), higher-resolution experiments have sought to decompose this integrated radiation into the contributions from individual galaxies. Here we report the results of an extragalactic survey at 250, 350 and 500um. Combining our results at 500 mum with those at 24um, we determine that all of the FIRB comes from individual galaxies, with galaxies at z greater than or equal to 1.2 accounting for 70% of it. As expected, at the longest wavelengths the signal is dominated by ultraluminous galaxies at z>1.
- ID:
- ivo://CDS.VizieR/J/ApJ/681/428
- Title:
- BLAST sources in Galactic plane survey
- Short Name:
- J/ApJ/681/428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from a new 250, 350, and 500um Galactic plane survey taken with the Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) in 2005. This survey's primary goal is to identify and characterize high-mass protostellar objects (HMPOs). The region studied here covers 4{deg}^2^ near the open cluster NGC 6823 in the constellation Vulpecula (l=59{deg}). We find 60 compact sources (<60" diameter) detected simultaneously in all three bands. Their SEDs are constrained through BLAST, IRAS, Spitzer MIPS, and MSX photometry, with inferred dust temperatures spanning ~12-40K assuming a dust emissivity index {beta}=1.5. The luminosity-to-mass ratio, a distance-independ ent quantity, spans ~0.2-130L_{sun}_/M_{sun}_. Distances are estimated from coincident ^13^CO(1-0) velocities combined with a variety of other velocity and morphological data in the literature. In total, 49 sources are associated with a molecular cloud complex encompassing NGC 6823 (distance ~2.3kpc), 10 objects with the Perseus arm (~8.5kpc), and one object is probably in the outer Galaxy (~14kpc). Near NGC 6823, the inferred luminosities and masses of BLAST sources span ~40-10^4^L_{sun}_ and ~15-700M_{sun}_, respectively. The mass spectrum is compatible with molecular gas masses in other high-mass star-forming regions. Several luminous sources appear to be ultracompact H II regions powered by early B stars. However, many of the objects are cool, massive gravitationally bound clumps with no obvious internal radiation from a protostar, and hence excellent HMPO candidates.
1917. BLAST survey in Vela-D
- ID:
- ivo://CDS.VizieR/J/ApJ/707/1836
- Title:
- BLAST survey in Vela-D
- Short Name:
- J/ApJ/707/1836
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Balloon-borne Large-Aperture Submillimeter Telescope (BLAST) carried out a 250, 350, and 500um survey of the Galactic plane encompassing the Vela Molecular Ridge, with the primary goal of identifying the coldest dense cores possibly associated with the earliest stages of star formation. Here, we present the results from observations of the Vela-D region, covering about 4deg^2^, in which we find 141 BLAST cores. We exploit existing data taken with the Spitzer MIPS, IRAC, and SEST-SIMBA instruments to constrain their (single-temperature) spectral energy distributions, assuming a dust emissivity index {beta}=2.0. This combination of data allows us to determine the temperature, luminosity, and mass of each BLAST core, and also enables us to separate starless from protostellar sources. We also analyze the effects that the uncertainties on the derived physical parameters of the individual sources have on the overall physical properties of starless and protostellar cores, and we find that there appear to be a smooth transition from the pre- to the protostellar phase. In particular, for protostellar cores we find a correlation between the MIPS24 flux, associated with the central protostar, and the temperature of the dust envelope. We also find that the core mass function of the Vela-D cores has a slope consistent with other similar (sub)millimeter surveys.
- ID:
- ivo://CDS.VizieR/J/ApJ/707/1779
- Title:
- BLAST: the redshift survey
- Short Name:
- J/ApJ/707/1779
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has recently surveyed ~8.7deg^2^ centered on Great Observatories Origins Deep Survey-South at 250, 350, and 500um. In Dye et al. (2009, Cat. J/ApJ/703/285), we presented the catalog of sources detected at 5{sigma} in at least one band in this field and the probable counterparts to these sources in other wavebands. In this paper, we present the results of a redshift survey in which we succeeded in measuring redshifts for 82 of these counterparts. The spectra show that the BLAST counterparts are mostly star-forming galaxies but not extreme ones when compared to those found in the Sloan Digital Sky Survey. Roughly one quarter of the BLAST counterparts contain an active nucleus. We have also investigated the cases where there are two possible counterparts to the BLAST source, finding that in at least half of these there is evidence that the two galaxies are physically associated, either because they are interacting or because they are in the same large-scale structure. Finally, we have made the first direct measurements of the luminosity function in the three BLAST bands.
1919. BLAST Vela sources
- ID:
- ivo://CDS.VizieR/J/ApJ/707/1824
- Title:
- BLAST Vela sources
- Short Name:
- J/ApJ/707/1824
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present first results from an unbiased 50deg^2^ submillimeter Galactic survey at 250, 350, and 500um from the 2006 flight of the Balloon-borne Large Aperture Submillimeter Telescope. The map has resolution ranging from 36" to 60" in the three submillimeter bands spanning the thermal emission peak of cold starless cores. We determine the temperature, luminosity, and mass of more than 1000 compact sources in a range of evolutionary stages and an unbiased statistical characterization of the population. From comparison with C^18^O data, we find the dust opacity per gas mass, {kappa}r=0.16cm^2^/g at 250um, for cold clumps. We find that 2% of the mass of the molecular gas over this diverse region is in cores colder than 14K, and that the mass function for these cold cores is consistent with a power law with index {alpha}=-3.22+/-0.14 over the mass range 14M_{sun}_<M<80M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/915
- Title:
- BLAST view of Aquila star-forming region
- Short Name:
- J/ApJ/723/915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out the first general submillimeter analysis of the field toward GRSMC 45.46+0.05, a massive star-forming region in Aquila. The deconvolved 6{deg}^2^ (3{deg}x2{deg}) maps provided by BLAST in 2005 at 250, 350, and 500um were used to perform a preliminary characterization of the clump population previously investigated in the infrared, radio, and molecular maps. Interferometric CORNISH data at 4.8GHz have also been used to characterize the Ultracompact HII regions (UCHIIRs) within the main clumps. By means of the BLAST maps, we have produced an initial census of the submillimeter structures that will be observed by Herschel, several of which are known Infrared Dark Clouds.
