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Start Over Subject submillimeter astronomy Validation Level 2
481. Sub-mm observations in Extended Chandra DFS
ID:
ivo://CDS.VizieR/J/MNRAS/411/505
Title:
Sub-mm observations in Extended Chandra DFS
Short Name:
J/MNRAS/411/505
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a joint analysis of the overlapping Balloon-borne Large Aperture Submillimetre Telescope (BLAST) 250, 350, 500um, and LABOCA 870um observations [from the LABOCA ECDFS Submm Survey (LESS) survey] of the Extended Chandra Deep Field-South. Out to z~3, the BLAST filters sample near the peak wavelength of thermal far-infrared (FIR) emission from galaxies (rest-frame wavelengths ~60-200um), primarily produced by dust heated through absorption in star-forming clouds. However, identifying counterparts to individual BLAST peaks is very challenging, given the large beams [full-width at half-maximum (FWHM) 36-60 arcsec]. In contrast, the ground-based 870um observations have a significantly smaller 19 arcsec FWHM beam, and are sensitive to higher redshifts (z~1-5, and potentially beyond) due to the more favourable negative K-correction. We use the LESS data, as well as deep Spitzer and VLA imaging, to identify 118 individual sources that produce significant emission in the BLAST bands.
482. Submm observations in gravitational lenses
ID:
ivo://CDS.VizieR/J/MNRAS/384/1611
Title:
Submm observations in gravitational lenses
Short Name:
J/MNRAS/384/1611
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a submillimetre mapping survey of faint, gravitationally lensed sources, where we have targeted 12 galaxy clusters and additionally the New Technology Telescope (NTT) Deep Field. The total area surveyed is 71.5arcmin^2^ in the image plane; correcting for gravitational lensing, the total area surveyed is 40arcmin^2^ in the source plane for a typical source redshift z>>2.5. In the deepest maps, an image plane depth of 1{sigma} rms ~0.8mJy is reached. This survey is the largest survey to date to reach such depths. In total 59 sources were detected, including three multiply imaged sources. The gravitational lensing makes it possible to detect sources with flux density below the blank field confusion limit. The lensing-corrected fluxes range from 0.11 to 19mJy. After correcting for multiplicity, there are 10 sources with fluxes <2mJy of which seven have submJy fluxes, doubling the number of such sources known. Number counts are determined below the confusion limit. At 1mJy, the integrated number count is ~10^4^deg^-2^, and at 0.5mJy it is ~2x10^4^deg^-2^. Based on the number counts, at a source plan flux limit of 0.1mJy, essentially all of the 850-m background emission has been resolved. The dominant contribution (>50 per cent) to the integrated background arises from sources with fluxes S850 between 0.4 and 2.5mJy, while the bright sources S850>6mJy contribute only 10 per cent.
483. Sub-mm observations of IRS43 and IRS63
ID:
ivo://CDS.VizieR/J/A+A/559/A82
Title:
Sub-mm observations of IRS43 and IRS63
Short Name:
J/A+A/559/A82
Date:
21 Oct 2021
Publisher:
CDS
Description:
A fundamental part of the study of star formation is to place young stellar objects in an evolutionary sequence. Establishing a robust evolutionary classification scheme allows us not only to understand how the Sun was born but also to predict what kind of main sequence star a given protostar will become. Traditionally, low-mass young stellar objects are classified according to the shape of their spectral energy distributions. Such methods are, however, prone to misclassification due to degeneracy and do not constrain the temporal evolution. More recently, young stellar objects have been classified based on envelope, disk, and stellar masses determined from resolved images of their continuum and line emission at submillimeter wavelengths. Through detailed modeling of two Class I sources, we aim at determining accurate velocity profiles and explore the role of freeze-out chemistry in such objects. We present new Submillimeter Array observations of the continuum and HCO^+^ line emission at 1.1mm toward two protostars, IRS 63 and IRS 43 in the Ophiuchus star forming region. The sources were modeled in detail using dust radiation transfer to fit the SED and continuum images and line radiation transfer to produce synthetic position-velocity diagrams. We used a chi^2^ search algorithm to find the best model fit to the data and to estimate the errors in the model variables. Our best fit models present disk, envelope, and stellar masses, as well as the HCO^+^ abundance and inclination of both sources. We also identify a ring structure with a radius of about 200AU in IRS 63. Conclusions. We find that freeze-out chemistry is important in IRS 63 but not for IRS 43. We show that the velocity field in IRS 43 is consistent with Keplerian rotation. Owing molecular depletion, it is not possible to draw a similar conclusion for IRS 63. We identify a ring-shaped structure in IRS 63 on the same spatial scale as the disk outer radius. No such structure is seen in IRS 43. We find that freeze-out chemistry is important in IRS 63 but not for IRS 43. We show that the velocity field in IRS 43 is consistent with Keplerian rotation. Owing molecular depletion, it is not possible to draw a similar conclusion for IRS 63. We identify a ring-shaped structure in IRS 63 on the same spatial scale as the disk outer radius. No such structure is seen in IRS 43.
484. Sub-mm observations of the HDF
ID:
ivo://CDS.VizieR/J/MNRAS/344/887
Title:
Sub-mm observations of the HDF
Short Name:
J/MNRAS/344/887
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an extended analysis of the Submillimetre Common User Bolometer Array (SCUBA) observations of the Hubble Deep Field (HDF), expanding the areal coverage of the Hughes et al. (1998Natur.394..241H) study by a factor of ~1.8 and containing at least three further sources in addition to the five in that study. We also announce the public release of the reduced data products. The map is the deepest ever made in the submillimetre (submm), obtained in excellent conditions (median 850-{mu}m optical depth of 0.16).
485. submm point sources from the Archeops experiment
ID:
ivo://CDS.VizieR/J/A+A/481/411
Title:
submm point sources from the Archeops experiment
Short Name:
J/A+A/481/411
Date:
21 Oct 2021
Publisher:
CDS
Description:
Archeops is a balloon-borne experiment, mainly designed to measure the Cosmic Microwave Background (CMB) temperature anisotropies at high angular resolution (~12 arcminutes). By-products of the mission are shallow sensitivity maps over a large fraction of the sky (about 30 %) in the millimetre and submillimetre range at 143, 217, 353 and 545GHz. From these maps, we produce a catalog of bright submillimetre point sources. We present in this paper the processing and analysis of the Archeops point sources. Redundancy across detectors is the key factor allowing us to distinguish glitches from genuine point sources in the 20 independent maps. We look at the properties of the most reliable point sources, totalling 304. Fluxes range from 1 to 10000Jy (at the frequencies covering 143 to 545GHz). All sources are either planets (2) or of galactic origin. The longitude range is from 75 to 198-degrees. Some of the sources are associated with the well-known Lynds Nebulae and HII compact regions in the galactic plane. A large fraction of the sources have an IRAS counterpart. Except for Jupiter, Saturn, the Crab and Cas A, all sources show a dust-emission-like modified blackbody emission spectrum. Temperatures cover a range from 7 to 27K. For the coldest sources (T<10K), a steep nu^beta^ emissivity law is found with a surprising beta~3 to 4. An inverse relationship between T and beta is observed. The number density of sources at 353GHz with flux brighter than 100Jy is of the order of 1 per degree of Galactic longitude. These sources will provide a strong check for the calibration of the Planck HFI focal plane geometry as a complement to planets. These very cold sources observed by Archeops should be prime targets for mapping observations by the Akari and Herschel space missions and ground-based observatories.
486. Submm polarization of Galactic clouds
ID:
ivo://CDS.VizieR/J/ApJS/201/13
Title:
Submm polarization of Galactic clouds
Short Name:
J/ApJS/201/13
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Hertz and SCUBA polarimeters, working at 350um and 850um, respectively, have measured the polarized emission in scores of Galactic clouds. Of the clouds in each data set, 17 were mapped by both instruments with good polarization signal-to-noise ratios. We present maps of each of these 17 clouds comparing the dual-wavelength polarization amplitudes and position angles at the same spatial locations.
487. Submm spectrum of deuterated glycolaldehydes
ID:
ivo://CDS.VizieR/J/A+A/540/A51
Title:
Submm spectrum of deuterated glycolaldehydes
Short Name:
J/A+A/540/A51
Date:
21 Oct 2021
Publisher:
CDS
Description:
Glycolaldehyde, a sugar-related interstellar prebiotic molecule, has recently been detected in two star-forming regions, Sgr B2(N) and G31.41+0.31. The detection of this new species increased the list of complex organic molecules detected in the interstellar medium (ISM) and adds another level to the chemical complexity present in space. Besides, this kind of organic molecule is important because it is directly linked to the origin of life. For many years, astronomers have been struggling to understand the origin of this high chemical complexity in the ISM. The study of deuteration may provide crucial hints.
488. (Sub)mm spectrum of deuterated methyl cyanides
ID:
ivo://CDS.VizieR/J/A+A/553/A84
Title:
(Sub)mm spectrum of deuterated methyl cyanides
Short Name:
J/A+A/553/A84
Date:
21 Oct 2021
Publisher:
CDS
Description:
The study of deuterated abundant molecules is recognized as important in understanding molecular complexity in star-forming regions. We seek to assign the laboratory millimeter and submillimeter wave rotational spectra of the CHD_2_CN and CH_2_DCN deuterated isotopologues of methyl cyanide over a wide frequency range in order to provide precise spectral predictions for observations.
489. Sulfur isotopes in SFR with 12m ARO and 30m IRAM
ID:
ivo://CDS.VizieR/J/ApJ/899/145
Title:
Sulfur isotopes in SFR with 12m ARO and 30m IRAM
Short Name:
J/ApJ/899/145
Date:
14 Mar 2022 07:08:41
Publisher:
CDS
Description:
We present observations of 12C32S, 12C34S, 13C32S, and 12C33S J=2-1 lines toward a large sample of massive star-forming regions by using the Arizona Radio Observatory 12m telescope and the IRAM 30m. Taking new measurements of the carbon 12C/13C ratio, the 32S/34S isotope ratio was determined from the integrated 13C32S/12C34S line intensity ratios for our sample. Our analysis shows a 32S/34S gradient from the inner Galaxy out to a galactocentric distance of 12kpc. An unweighted least-squares fit to our data yields 32S/34S=(1.56{+/-}0.17)DGC+(6.75{+/-}1.22) with a correlation coefficient of 0.77. Errors represent 1{sigma} standard deviations. Testing this result by (a) excluding the Galactic center region, (b) excluding all sources with C34S opacities >0.25, (c) combining our data and old data from previous study, and (d) using different sets of carbon isotope ratios leads to the conclusion that the observed 32S/34S gradient is not an artifact but persists irrespective of the choice of sample and carbon isotope data. A gradient with rising 32S/34S values as a function of galactocentric radius implies that the solar system ratio should be larger than that of the local interstellar medium. With the new carbon isotope ratios, we indeed obtain a local 32S/34S isotope ratio about 10% below the solar system one, as expected in the case of decreasing 32S/34S ratios with time and increased amounts of stellar processing. However, taking older carbon isotope ratios based on a lesser amount of data, such a decrease is not seen. No systematic variation of 34S/33S ratios along galactocentric distance was found. The average value is 5.9{+/-}1.5, the error denoting the standard deviation of an individual measurement.
490. Sunyaev-Zel'dovich effect in galaxy clusters
ID:
ivo://CDS.VizieR/J/MNRAS/376/1073
Title:
Sunyaev-Zel'dovich effect in galaxy clusters
Short Name:
J/MNRAS/376/1073
Date:
21 Oct 2021
Publisher:
CDS
Description:
In a search for evidence of the short wavelength increment in the Sunyaev-Zel'dovich (SZ) effect, we have analysed archival galaxy cluster data from the Submillimetre Common User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope, resulting in the most complete pointed survey of clusters at 850{mu}m to date. SCUBA's 850{mu}m passband overlaps the peak of the SZ increment. The sample consists of 44 galaxy clusters in the range 0<z<1.3. Maps of each of the clusters have been made and sources have been extracted; as an ancillary product, we generate the most thorough galaxy cluster point source list yet from SCUBA. 17 of these clusters are free of obvious active galactic nuclei (AGN) and have data deep enough to provide interesting measurements of the expected SZ signal.