- ID:
- ivo://CDS.VizieR/J/A+A/543/A46
- Title:
- Submillimeter spectrum of HCOOCD_2_H
- Short Name:
- J/A+A/543/A46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Astronomical surveys of interstellar molecules, such as those that will be available with the very sensitive ALMA telescope, require preliminary laboratory investigations of the microwave and submillimeter-wave spectra of new molecular species to identify these in the interstellar media. We build a linelist that should allow us to detect HCOOCD_2_H, provided it is present in the interstellar media in a suitable concentration.
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- ID:
- ivo://CDS.VizieR/J/ApJ/644/990
- Title:
- Sub-mm clumps at 450 and 850{mu}m in M17
- Short Name:
- J/ApJ/644/990
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have mapped a 5.5x5.5pc portion of the M17 massive star-forming region in both 850 and 450{mu}m dust continuum emission using the Submillimeter Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). The maps reveal more than 100 dusty clumps with deconvolved linear sizes of ~0.05-0.2pc and masses of ~0.8-120M_{sun}_, most of which are not associated with known mid-infrared point sources. Fitting the clump mass function with a double power law gives a mean power-law exponent of {alpha}high=-2.4+/-0.3 for the high-mass power law, consistent with the exponent of the Salpeter stellar mass function. We show that a lognormal clump mass distribution with a peak at 4M_{sun}_ produces as good a fit to the clump mass function as does a double power law. This 4M_{sun}_ peak mass is well above the peak masses of both the stellar initial mass function and the mass function of clumps in low-mass star-forming regions. Despite the difference in intrinsic mass scale, the shape of the M17 clump mass function appears to be consistent with the shape of the core mass function in low-mass star-forming regions. Thus, we suggest that the clump mass function in high-mass star-forming regions may be a scaled up version of that in low-mass regions, instead of its extension to higher masses.
- ID:
- ivo://CDS.VizieR/J/ApJ/639/259
- Title:
- Sub-mm clumps in Orion B South molecular cloud
- Short Name:
- J/ApJ/639/259
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey of a 1300arcmin^2^ region of the Orion B South molecular cloud, including NGC 2024, NGC 2023, and the Horsehead Nebula (B33), obtained using the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). Submillimeter continuum observations at 450 and 850{mu}m are discussed. Using an automated algorithm, 57 discrete emission features ("clumps") are identified in the 850{mu}m map.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A32
- Title:
- Sub-mm images of SSTB213 J041757.75+274105.5
- Short Name:
- J/A+A/564/A32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed the proto brown dwarf candidate SSTB213 J041757 with the Submillimeter Array to search for CO molecular outflow emission from the source. Our CO maps do not show any outflow emission from the proto brown dwarf candidate. The non-detection implies that the molecular outflows from the source are weak; deeper observations are therefore needed to probe the outflows from the source.
- ID:
- ivo://CDS.VizieR/J/ApJ/559/307
- Title:
- Sub-mm mapping in Orion B molecular cloud
- Short Name:
- J/ApJ/559/307
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a survey of a 900 arcmin^2^ region of the Orion B molecular cloud, including NGC 2068, NGC 2071, and HH 24/25/26, at 850{mu}m using the Submillimeter Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope. Following the techniques developed by Johnstone et al. (2000ApJ...545..327J), we identify 75 independent objects and compute size, flux, and degree of central concentration. Comparison with isothermal, pressure-confined, self-gravitating Bonnor-Ebert spheres implies that the clumps have internal temperatures of 20-40K and surface pressures 5.5<log(P/k)[CGS]<6.5. The clump masses span 0.2-12.3M_{sun}_ assuming typical dust temperatures and a dust emissivity {kappa}_850_=0.01cm^2^/g.
- 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.
- 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.
- 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.
- 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.
- 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.