- ID:
- ivo://CDS.VizieR/J/A+A/631/A154
- Title:
- IRAS 15398-3359 polarization maps
- Short Name:
- J/A+A/631/A154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Magnetic fields can significantly affect the star formation process. The theory of the magnetically driven collapse in a uniform field predicts that the contraction initially happens along the field lines. When the gravitational pull grows strong enough, the magnetic field lines pinch inwards, giving rise to a characteristic hourglass shape. We investigate the magnetic field structure of a young Class 0 object, IRAS 15398-3359, embedded in the Lupus I cloud. Previous observations at large scales have suggested that this source evolved in an highly magnetised environment. This object thus appears to be an ideal candidate to study the magnetically driven core collapse in the low-mass regime. We performed polarisation observations of IRAS 15398-3359 at 214um using the SOFIA telescope, thus tracing the linearly polarised thermal emission of cold dust. Our data unveil a significant bend of the magnetic field lines from the gravitational pull. The magnetic field appears ordered and aligned with the large-scale B-field of the cloud and with the outflow direction. We estimate a magnetic field strength of B=78uG, which is expected to be accurate within a factor of two. The measured mass-to-flux parameter is {lambda}=0.95, indicating that the core is in a transcritical regime.
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- ID:
- ivo://CDS.VizieR/II/338
- Title:
- IRAS PSC/FSC Combined Catalogue
- Short Name:
- II/338
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical identifications of a few thousands of IRAS sources showed that IRAS Point Source and IRAS Faint Source catalogues (PSC and FSC, respectively) contain many quasars and active galactic nuclei, late-type stars, planetary nebulae, variables, etc. To increase the efficiency of using IRAS PSC and FSC, which contain a lot of common sources, one needs a joint catalogue of all IRAS point sources with improved data based on both catalogues. However, cross-correlation of the catalogues is not so easy, as the association of many sources is relative, and not always it is obvious, whose source from one catalogue corresponds to the other one in the second catalogue. This problem exists in case of using standard cross-correlation tools. Therefore, we have created a tool for cross-matching astronomical catalogues and we have applied it to IRAS PSC and FSC. Using this tool we have carried out identifications with a search radius corresponding to 3-{sigma} of errors for each source individually rather than a standard radius for all sources. As a result, we obtained 73,770 associations. In addition, we have made cross-correlations with AKARI-IRC, AKARI-FIS and WISE catalogues. We created a catalogue of 345,163 IRAS sources with high positional accuracy and with 17 photometric measurements from 1.25 to 160 ?m range, providing a detailed catalogue for IRAS point sources.
- ID:
- ivo://CDS.VizieR/J/ApJS/89/189
- Title:
- IRAS PSC new OH/IR stars. III.
- Short Name:
- J/ApJS/89/189
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of 1612MHz observations conducted at the Arecibo Observatory of 571 color-selected sources from the IRAS Point Source Catalog. Of these sources we detect 132, 113 for the first time. This is the third part of an Arecibo survey of color-selected IRAS sources. The earlier two parts together detected a total of 268 sources of 1612MHz emission. An analysis of the properties of the OH/IR stars detected in all three parts of the survey is included. In particular we compute the limiting 1612MHz peak flux of the entire survey to be ~40mJy. The correlation between the IRAS infrared fluxes and the 1612MHz flux of the 132 sources detected in part III of the survey is smaller than that found in the earlier parts of the survey. This is to be expected from the intrinsic variability of OH/IR stars and the longer time gap between the 1612MHz observations and the IRAS measurements. We identify a subset of 54 stars as being near the tangent point of the galactic rotation curve. Using the kinematical distances to these stars we find that the efficiency of momentum transfer varies exponentially with the (25-12){mu}m color, consistent with the stellar outflow being driven by radiation pressure. Further the IR pump efficiency increases with increasing optical depth of the circumstellar shell, as expected for radiative pumping. The bolometric luminosity function is found to decrease sharply above L_Bol_=5600L_{sun}_, and the 1612MHz luminosity function shows a corresponding falloff above L_1612_=1.8x10^-8^L_{sun}_. We also find direct confirmation of the expectation that sources with large expansion velocity are more luminous than sources with small expansion velocity.
- ID:
- ivo://CDS.VizieR/II/126
- Title:
- IRAS Serendipitous Survey Catalog
- Short Name:
- II/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is a catalog of 12, 25, 60 and 100 micron photometric observations of 43,866 point-like sources detected fortuitiously in the Infrared Astronomical Satellite Pointed Observation program. The main objective was to take advantage of the longer-than-nominal integration time per source to extend the detection threshold relative to that of the Point Source Catalog (PSC); about three-fourths of the Serendipitous Survey Catalog (SSC) sources do not appear in the PSC. From 1813 Pointed Observation fields, the effective sky coverage is 1108 square degrees. Relative to the PSC, the SSC is characterized by: enhanced sensitivity (by a factor of about 4) in all four wavelength bands; excellent reliability in uncrowded fields; uneven sky coverage and completeness; reduced positional accuracy; improved photometric accuracy; much greater depth in crowded fields at the expense of reliability and accuracy. The SSC data processing, the catalog format, and an analysis are given in the Explanatory Supplement to the IRAS Serendipitous Survey Catalog.
- ID:
- ivo://CDS.VizieR/J/PASJ/54/719
- Title:
- IRAS/SiO sources in the Galactic bulge
- Short Name:
- J/PASJ/54/719
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared imaging observations of IRAS sources with SiO masers were made with the 2.3-m telescope of the Australian National University at Siding Spring Observatory, Australia, on 1997 June 18-23, 1998 June 9-12, and 2000 July 16-19, using the infrared array camera CASPIR. These infrared observations were made in parallel with long-term (1997-1999) SiO maser surveys at Nobeyama. The near-infrared observations were made within a year or so of the SiO detections. The details of the observations, data reduction, and method of identification were described in Deguchi et al. (1998PASJ...50..597D, 2001, Cat. <J/PASJ/53/293>), so they are not repeated here. All of the sources discussed in this paper are IRAS sources with detected SiO masers in the sky region of -10{deg}<l<15{deg} and |b|<3{deg} (Deguchi et al., 2000ApJS..130..351D).
- ID:
- ivo://CDS.VizieR/J/PASJ/53/293
- Title:
- IRAS/SiO sources toward Galactic Bulge
- Short Name:
- J/PASJ/53/293
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared photometric observations in the J-, H-, and K-bands have been made for 86 IRAS sources toward the inner Galactic bulge (|l|<3{deg} and |b|<3{deg}). SiO maser emission has previously been detected in all of these sources; they are well-confirmed, mass-losing, late-type stars having accurate radial velocities derived from SiO observations. For 78 sources, single, unambiguous near-infrared counterparts were found within the errors of the IRAS positions; for the other 8 sources, multiple candidates, candidates with a low confidence level, or candidates overlapped with other stars were found. From the J-, H-, K-band and IRAS 12 and 25{mu}m intensities, we estimated the spectral energy distributions of the sources, and obtained the distances, assuming a constant luminosity. The derived distances of the IRAS/SiO sources are consistent with the current bar model of the Galactic bulge, where the near side of the bar is located in the first quadrant of the galactic longitude. We also reanalyzed the radial velocity shift with distance, and confirmed the presence of streaming motions of stars in the bar-like bulge.
- ID:
- ivo://CDS.VizieR/VII/73
- Title:
- IRAS Small Scale Structure Catalog, Ver 1.00
- Short Name:
- VII/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Sources resolved by the Infrared Astronomical Satellite in any band (12, 25, 60, or 100 microns) but smaller than eight arcmin in angular extent are to be found in the Small Scale Structure Catalog, also known as the catalog of "small extended sources." The catalog gives the infrared characteristics of 16740 objects including, e.g., galaxies, planetary nebulae and compact H II regions. The catalog lists for each entry and in each band separately: a position accurate to about one arcminute (rms); a flux density accurate to 50% (rms) overall, and better at high signal to noise ratios; a rough indicative size if a point source is present at the same location; and a variety of warning and processing flags. If a detailed shape description, or a more accurate position, flux, or size are needed, these must be determined from the raw detector output. Incompleteness is a complex function of wavelength band, brightness, and location, so the absence of an entry in the SSS Catalog does not necessarily imply the lack of detectable extended emission. Many entries, mostly at 60 and 100 microns, refer only to emission features that are details in larger structures known as Galactic cirrus. Complete documentation, including a description of the catalog format, is contained in the printed version.
- ID:
- ivo://CDS.VizieR/J/A+AS/80/149
- Title:
- IRAS Sources behind the Solar circle
- Short Name:
- J/A+AS/80/149
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CO (J=1->0) has been observed with the 15-m SEST and the 30-m IRAM telescope in the direction of 1302 IRAS sources with colors of star forming regions located within 10 deg of the galactic plane in the interval between 85 and 280 deg. Emission components with line profiles that are non-Gaussian (showing, e.g., possible self-absorption or wings) are identified; this information may serve as a basis for selecting sources for future research. For all components, kinematic heliocentric and galactocentric distances, and distances from the galactic plane are derived. For those components which may be associated with the IRAS sources, bolometric luminosities are derived. These data will be analyzed and compared with HI data in subsequent papers.
- ID:
- ivo://CDS.VizieR/J/A+AS/98/589
- Title:
- IRAS Sources behind the Solar circle
- Short Name:
- J/A+AS/98/589
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/626/A93
- Title:
- IRAS 16293-2422 spectral cubes
- Short Name:
- J/A+A/626/A93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The majority of stars form in binary or higher order systems. The Class 0 protostellar system IRAS16293-2422 contains two protostars, 'A' and 'B', separated by ~600au and embedded in a single, 10^4 au scale envelope. Their relative evolutionary stages have been debated. We aim to study the relation and interplay between the two protostars A and B at spatial scales of 60 to ~1000au. We selected molecular gas line transitions of CO, H_2_CO, HCN, CS, SiO, and CCH from the ALMA-PILS spectral imaging survey (329-363GHz) and used them as tracers of kinematics, density, and temperature in the IRAS16293-2422 system. The angular resolution of the PILS data set allows us to study these quantities at a resolution of 0.5 arcsec (60 au at the distance of the source). Line-of-sight velocity maps of both optically thick and optically thin molecular lines reveal: (i) new manifestations of previously known outflows emanating from protostar A; (ii) a kinematically quiescent bridge of dust and gas spanning between the two protostars, with an inferred density between 4x10^4^ and 3x10^7^cm^-3^; and (iii) a separate, straight filament seemingly connected to protostar B seen only in CCH, with a flat kinematic signature. Signs of various outflows, all emanating from source A, are evidence of high-density and warmer gas; none of them coincide spatially and kinematically with the bridge. We hypothesize that the bridge arc is a remnant of filamentary substructure in the protostellar envelope material from which protostellar sources A and B have formed. One particular morphological structure appears to be due to outflowing gas impacting the quiescent bridge material. The continuing lack of clear outflow signatures unambiguously associated to protostar B and the vertically extended shape derived for its disk-like structure lead us to conclude that source B may be in an earlier evolutionary stage than source A.
