- 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.
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Search Results
- 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/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.
- ID:
- ivo://CDS.VizieR/J/other/BSAO/50.115
- Title:
- IRAS-TEXAS cross-identifications
- Short Name:
- J/other/BSAO/50.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A procedure of sampling objects by way of cross-identification of the low-frequency radio catalogue of objects obtained with the aid of the Texas interferometer at the frequency 365MHz and of the IRAS (Cat. <II/125>) catalogue is discussed. Statistical properties of different subsamples of sources are investigated. From the results of cross-identification with the radio catalogues of the database CATS (Verkhodanov et al., 1997BaltA...6..275V), continuous radio spectra of objects are plotted, identification with optical and X-ray catalogues is carried out. From the steep spectrum objects sources are selected for further studies.
- ID:
- ivo://CDS.VizieR/J/A+A/600/A87
- Title:
- IRAS17020+4544 VLBA 5, 8, 15, 24GHz images
- Short Name:
- J/A+A/600/A87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent XMM-Newton observations have revealed that IRAS 17020+4544 is a very unusual example of black hole windproduced feedback by a moderately luminous AGN in a spiral galaxy. Since the source is known for being a radio emitter, we investigated about the presence and the properties of a non-thermal component. We observed IRAS 17020+4544 with the Very Long Baseline Array at 5, 8, 15, and 24GHz within a month of the 2014 XMM-Newton observations. We further analysed archival data taken in 2000 and 2012. Results. We detect the source at 5GHz and on short baselines at 8GHz. At 15 and 24 GHz, the source is below our baseline sensitivity for fringe fitting, indicating the lack of prominent compact features. The morphology is that of an asymmetric double, with significant diffuse emission. The spectrum between 5 and 8GHz is rather steep (S{nu}~nu^-(1.0+/-0.2)^). Our re-analysis of the archival data at 5 and 8GHz provides results consistent with the new observations, suggesting that flux density and structural variability are not important in this source. We put a limit on the separation speed between the main components of <0.06c. IRAS 17020+4544 shows interesting features of several classes of objects: its properties are typical of compact steep spectrum sources, low power compact sources, radio-emitting narrow line Seyfert 1 galaxies. However, it can not be classified in any of these categories, remaining so far a one-of-a-kind object.
- ID:
- ivo://CDS.VizieR/J/ApJ/628/789
- Title:
- IRAS03301+3057 water masers
- Short Name:
- J/ApJ/628/789
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we present VLA observations of the NH3, CCS, and H2O maser emission at 1cm from the star-forming region B1-IRS (IRAS 03301+3057) with ~5" (=1750AU) of angular resolution. The CCS emission is distributed in three clumps around the central source. These clumps exhibit a velocity gradient from red- to blueshifted velocities toward B1-IRS, probably due to an interaction with the outflow from an embedded protostar.
- ID:
- ivo://CDS.VizieR/J/A+A/601/A4
- Title:
- IRC+10216 carbon chains mapped with ALMA
- Short Name:
- J/A+A/601/A4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Linear carbon chains are common in various types of astronomical molecular sources. Possible formation mechanisms involve both bottom-up and top-down routes. We have carried out a combined observational and modeling study of the formation of carbon chains in the C-star envelope IRC +10216, where the polymerization of acetylene and hydrogen cyanide induced by ultraviolet photons can drive the formation of linear carbon chains of increasing length. We have used ALMA to map the emission of 3 mm rotational lines of the hydrocarbon radicals C_2_H, C_4_H, and C_6_H, and the CN-containing species CN, C_3_N, HC_3_N, and HC_5_N with an angular resolution of 1". The spatial distribution of all these species is a hollow 5-10" wide spherical shell located at a radius of 10-20" from the star, with no appreciable emission close to the star. Our observations resolve the broad shell of carbon chains into thinner subshells that are 1-2" wide and not fully concentric, indicating that the mass-loss process has been discontinuous and not fully isotropic. The radial distributions of the species mapped reveal subtle differences: while the hydrocarbon radicals have very similar radial distributions, the CN-containing species show more diverse distributions, with HC_3_N appearing earlier in the expansion and the radical CN extending later than the rest of the species. The observed morphology can be rationalized by a chemical model in which the growth of polyynes is mainly produced by rapid gas-phase chemical reactions of C_2_H and C_4_H radicals with unsaturated hydrocarbons, while cyanopolyynes are mainly formed from polyynes in gas-phase reactions with CN and C_3_N radicals.