- 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.
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Search Results
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/633/A7
- Title:
- IRAS 16293-2422 spectral cubes
- Short Name:
- J/A+A/633/A7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Temperature is a crucial parameter in circumstellar disk evolution and planet formation because it governs the resistance of the gas to gravitational instability and sets the chemical composition of the planet-forming material. We set out to determine the gas temperature of the young disk-like structure around the Class 0 protostar IRAS 16293-2422A. We used Atacama Large Millimeter/submillimeter Array (ALMA) observations of multiple H_2_CS J=7-6 and J=10-9 lines from the Protostellar Interferometric Line Survey (PILS) to create a temperature map for the inner ~200AU of the disk-like structure. This molecule is a particularly useful temperature probe because transitions between energy levels with different K_a quantum numbers operate only through collisions. Based on the H_2_CS line ratios, the temperature is between ~100-175K in the inner ~150AU, and drops to ~75K at ~200AU. At the current resolution (0.5"~70AU), no jump is seen in the temperature at the disk-envelope interface. The temperature structure derived from H_2_CS is consistent with envelope temperature profiles that constrain the temperature from 1000AU scales down to ~100AU, but does not follow the temperature rise seen in these profiles at smaller radii. Higher angular resolution observations of optically thin temperature tracers are needed to establish whether cooling by gas-phase water, the presence of a putative disk, or the dust optical depth influences the gas temperature at <~100AU scales. The temperature at 100AU is higher in IRAS 16293A than in the embedded Class 0/I disk L1527, consistent with the higher luminosity of the former.
- ID:
- ivo://CDS.VizieR/J/A+A/622/A38
- Title:
- IRAS05168+3634 star-forming region stellar content
- Short Name:
- J/A+A/622/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Aims. We report the investigation results of the structure and content of a molecular cloud surrounding the source IRAS 05168+3634 (also known as Mol 9). Methods. We present a photometric analysis using the data of J, H, K UKIDSS, [3.6], [4.5]{mu}m Spitzer-IRAC and 3.4, 4.6, 12, 22{mu}m WISE databases. A multi-color criteria was used to identify the candidates of young stellar objects (YSOs) in the molecular cloud; in addition to IRAS 05168+3634, there are four IRAS sources embedded in the same molecular cloud. Color-magnitude diagrams and the K luminosity function (KLF) were used to determine the basic parameters of stellar objects (spectral classes, masses, ages). To study the YSOs with longer wavelength photometry the radiative transfer models were used. Results. Based on color-color and color-magnitude diagrams, we identified a rich population of embedded YSO candidates with infrared excess (Class 0/I and Class II) and their characteristics in a quite large molecular cloud located in a region of 24 arcmin radius. The molecular cloud includes 240 candidates of YSOs within the radii of subregions around five IRAS sources. The local distribution of identified YSOs in the molecular cloud frequently shows elongation and subclustering. The observed young subregions and parental molecular cloud morphologies are similar, especially when only the youngest Class I/0 sources are considered. The color-magnitude diagrams of the subregions suggest a very young stellar population. We construct the KLF of the subregions except for the IRAS 05162+3639 region and it shows unusually low values for {alpha} slope: 0.12-0.21. According to the values of the slopes of the KLFs, the age of the subregions can be estimated at 0.1-3Myr. The spectral energy distributions (SEDs) are constructed for 45 Class I and 75 Class II evolutionary stage YSOs and the received parameters of these YSOs are well correlated with the results obtained by other methods. According to the results of SED fitting tool, the sources IRAS 05184+3635, IRAS 05177+3636, and IRAS 05162+3639 can be classified as Class I evolutionary stage objects. IRAS 05168+3634 and IRAS 05156+3643 can be classified as flat-spectrum objects.
- 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/A+A/649/A84
- Title:
- IR band features around HD100546
- Short Name:
- J/A+A/649/A84
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Carbonaceous nanograins are present at the surface of protoplanetary disks around Herbig Ae/Be stars, where most of the ultraviolet energy from the central star is dissipated. Efficiently coupled to the gas, they are unavoidable to understand the physics and chemistry of these disks. Furthermore, nanograins are able to trace the outer flaring parts of the disk and possibly the gaps from which the larger grains are missing. However, their evolution through the disks, from internal to external regions, is only poorly understood so far. Our aim is to examine the spatial distribution and evolution of the nanodust emission in the emblematic (pre-)transitional protoplanetary disk HD 100546. This disk shows many structures (annular gaps, rings, and spirals) and reveals very rich carbon nanodust spectroscopic signatures (aromatic, aliphatic) in a wide spatial range of the disk (~20-200au). We analysed adaptive optics spectroscopic observations in the 3-4um range (angular resolution of ~0.1") and imaging and spectroscopic observations in the 8-12um range (angular resolution of ~0.3"). The hyperspectral cube was decomposed into a sum of spatially coherent dust components using a Gaussian decomposition algorithm. We compared the data to model predictions using the heterogeneous dust evolution model for interstellar solids (THEMIS), which is integrated in the radiative transfer code POLARIS by calculating the thermal and stochastic heating of micro- and nanometre-sized dust grains for a given disk structure. We find that the aromatic features at 3.3, 8.6, and 11.3um, and the aliphatic features between 3.4 and 3.5um are spatially extended; each band shows a specific morphology dependent on the local physical conditions. The aliphatic-to-aromatic band ratio, 3.4/3.3, increases with the distance from the star from ~0.2 (at 0.2" or 20au) to ~0.45 (at 1" or 100au), suggesting UV processing. In the 8-12um observed spectra, several features characteristic of aromatic particles and crystalline silicates are detected. Their relative contribution changes with the distance to the star. The model predicts that the features and adjacent continuum are due to different combinations of grain sub-populations, in most cases with a high dependence on the intensity of the UV field. The model reproduces the spatial emission profiles of the bands well, except for the inner 20-40au, where the observed emission of the 3.3 and 3.4um bands is, unlike the predictions, flat and no longer increases with the UV field. With our approach that combines observational data in the near- to mid-IR and disk modelling, we deliver constraints on the spatial distribution of nano-dust particles as a function of the disk structure and radiation field.
