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831. Sub-mm mapping in Orion B molecular cloud
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.
832. 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.
833. 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.
834. 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.
835. (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.
836. 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.
837. Suppl. to Diffuse Interstellar Band Measurements
ID:
ivo://CDS.VizieR/II/135
Title:
Suppl. to Diffuse Interstellar Band Measurements
Short Name:
II/135
Date:
21 Oct 2021
Publisher:
CDS
Description:
This bibliographic search has been undertaken in order to gather all data concerning four diffuse interstellar bands (DIB) published since the Snow, York, and Welty (1977) catalogue, and up to 1987.0. These four DIB are : 4430, 5780, 5797, and 6284 Angstrom. In the present set of data, no statistical reduction to a unique system has been made because most of the lists contain only few data.
838. Survey of diffuse interstellar bands
ID:
ivo://CDS.VizieR/J/MNRAS/423/725
Title:
Survey of diffuse interstellar bands
Short Name:
J/MNRAS/423/725
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents an atlas of diffuse interstellar bands together with tables with measurements of their parameters: central wavelengths, full widths at half-maximum and equivalent widths. For this goal the spectra of ten reddened, early-type stars have been selected. The spectra are of high resolution, ~100000, and reasonable signal-to-noise ratio, S/N>300; they cover a wide spectral range 3500-10000{AA} and show a lack of evident Doppler splitting in the interstellar KI line. The measurement technique has allowed a homogeneous set of data to be achieved. As a result, the identity of 336 DIBs from previous surveys has been confirmed and 21 new bands have been found.
839. Survey of infall motions toward starless cores
ID:
ivo://CDS.VizieR/J/ApJ/526/788
Title:
Survey of infall motions toward starless cores
Short Name:
J/ApJ/526/788
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results of a survey of 220 starless cores selected primarily by their optical obscuration and observed in CS (2-1), N_2_H^+^ (1-0), and C^18^O (1-0) using the Northeast Radio Observatory Corporation (NEROC) Haystack 37 m telescope. We have detected 163 out of 196 sources observed in CS, 72 out of 142 in N_2_H^+^, and 30 out of 30 in C18O. In total, 69 sources were detected in both CS and N_2_H^+^. The isolated component of the N_2_H^+^ (1-0) spectrum (F_1_F = 0,1-1,2) usually shows a weak symmetric profile that is optically thin. In contrast, a significant fraction of the CS spectra show non-Gaussian shapes, which we interpret as arising from a combination of self-absorption due to lower excitation gas in the core front and kinematics in the core. The distribution of the normalized velocity difference ({delta}V_CS_) between the CS and N_2_H^+^ peaks appears significantly skewed to the blue (V_CS_ < 0), as was found in a similar study of dense cores with embedded young stellar objects (YSOs). The incidence of sources with blue asymmetry tends to increase as the total optical depth or the integrated intensity of the N_2_H^+^ line increases.
840. Survey of SiO maser emission in oxygen-rich stars
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.