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- ID:
- ivo://CDS.VizieR/J/AZh/82/420
- Title:
- Spectral study of 19 radio sources
- Short Name:
- J/AZh/82/420
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical identifications, classifications, and radio spectra of 19 radio sources from a complete sample in flux-density with the declinations 10{deg}-12{deg}30' (J2000) obtained with the 6-m optical telescope (4000-9000{AA}) and RATAN-600 radio telescope (0.97-21.7GHz) of the Special Astrophysical Observatory. Twelve objects with redshifts from 0.573-2.694 have been classified as quasars, and two objects with featureless spectra as BL Lac objects. Four objects are emission-line radio galaxies with redshifts from 0.204 to 0.311, one object is an absorption-line radio galaxy with redshift 0.214. Radio flux densities have been obtained at six frequencies for all sources except for two extended objects. The radio spectra of five of the sources can be separated into extended and compact components. Three objects display substantial rapid and long-term variability of their flux densities.
- ID:
- ivo://CDS.VizieR/J/ApJS/174/313
- Title:
- Spectra of 388 bright 74MHz sources
- Short Name:
- J/ApJS/174/313
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a service to the community, we have compiled radio frequency spectra from the literature for all sources within the VLA Low Frequency Sky Survey (VLSS) that are brighter than 15Jy at 74MHz. Over 160 references were used to maximize the amount of spectral data used in the compilation of the spectra, while also taking care to determine the corrections needed to put the flux densities from all reference on the same absolute flux density scale. With the new VLSS data, we are able to vastly improve on previous efforts to compile spectra of bright radio sources to frequencies below 100MHz because (1) the VLSS flux densities are more reliable than those from some previous low-frequency surveys and (2) the VLSS covers a much larger area of the sky ({delta}>-30{deg}) than many other low-frequency surveys (e.g., the 8C survey).
- ID:
- ivo://CDS.VizieR/J/ApJ/815/49
- Title:
- Spectropolarimetric survey of radio sources
- Short Name:
- J/ApJ/815/49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a broadband spectropolarimetric survey of 563 discrete, mostly unresolved radio sources between 1.3 and 2.0 GHz using data taken with the Australia Telescope Compact Array. We have used rotation-measure synthesis to identify Faraday-complex polarized sources, those objects whose frequency-dependent polarization behavior indicates the presence of material possessing complicated magnetoionic structure along the line of sight (LOS). For sources classified as Faraday-complex, we have analyzed a number of their radio and multiwavelength properties to determine whether they differ from Faraday-simple polarized sources (sources for which LOS magnetoionic structures are comparatively simple) in these properties. We use this information to constrain the physical nature of the magnetoionic structures responsible for generating the observed complexity. We detect Faraday complexity in 12% of polarized sources at ~1' resolution, but we demonstrate that underlying signal-to-noise limitations mean the true percentage is likely to be significantly higher in the polarized radio source population. We find that the properties of Faraday-complex objects are diverse, but that complexity is most often associated with depolarization of extended radio sources possessing a relatively steep total intensity spectrum. We find an association between Faraday complexity and LOS structure in the Galactic interstellar medium (ISM) and claim that a significant proportion of the Faraday complexity we observe may be generated at interfaces of the ISM associated with ionization fronts near neutral hydrogen structures. Galaxy cluster environments and internally generated Faraday complexity provide possible alternative explanations in some cases.
- ID:
- ivo://CDS.VizieR/J/AJ/124/2453
- Title:
- Spectroscopy of active galaxies in nearby clusters
- Short Name:
- J/AJ/124/2453
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used optical spectroscopy to investigate the active galaxy populations in a sample of 20 nearby Abell clusters. The targets were identified on the basis of 1.4GHz radio emission, which identifies them as either active galactic nuclei (AGNs) or galaxies forming stars at rates comparable to or greater than that of the Milky Way. The spectra were used to characterize the galaxies via their emission and absorption features.
- ID:
- ivo://CDS.VizieR/J/AJ/114/122
- Title:
- Spectroscopy of edge-on spirals
- Short Name:
- J/AJ/114/122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present H I line observations of 744 edge-on spiral galaxies, extracted from the Flat Galaxy Catalog of Karachentsev et al. (1993AN....314...97K). Fluxes, systemic velocities and line widths are given for 587 detected galaxies, as well as search parameters for 157 undetected systems. Widths are corrected for instrumental broadening, smoothing, signal-to-noise and profile shape, and an estimate of the error on the width is given. When corrected for turbulent broadening and inclination angle of the disks, the velocity widths presented here can provide the appropriate line width parameter needed to derive distances via the Tully-Fisher relation.
- ID:
- ivo://CDS.VizieR/J/AZh/72/12
- Title:
- Spectroscopy of Sources from 87GB Catalog
- Short Name:
- J/AZh/72/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 112 sources with flux densities higher than 200mJy at the 4.85GHz and with the range of declinations from +3 till +5 degrees from the Green Bank survey catalog 87GB <VIII/14> was observed at three frequencies: 0.96, 3.95, and 11.1GHz. The observations were performed in January and February 1992, in the Northern sector of the RATAN-600 radio telescope. The accuracy of the source right ascensions was improved by a factor of 5-10 (for 70% of the sources the accuracy of the right ascension is 0.1arcsec). About 80% of the objects studied were identified with sources from the Texas survey.
- ID:
- ivo://CDS.VizieR/J/AJ/132/2596
- Title:
- Spectroscopy of Ultraluminous IR galaxies
- Short Name:
- J/AJ/132/2596
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the types of nuclear environments that produce OH megamasers (OHMs) with a study of the optical spectra of 40 OHM host galaxies and a control sample of 30 non-masing (ultra)luminous infrared galaxies ([U]LIRGs). The optical spectrophotometry provides spatially resolved spectra of multiple nuclei in a few of these merging systems. Of the 40 OHMs classified, 33% are starbursts, 42% are LINERs, and 25% are Seyfert 2 galaxies; the classification of the non-masing control sample is similar.
- ID:
- ivo://CDS.VizieR/J/A+A/605/A76
- Title:
- Spectrum of Orion KL between 41.5 and 50GHz
- Short Name:
- J/A+A/605/A76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We resent a sensitive spectral survey of Orion KL in Q-band (7mm), made with one of the 34m antennas of the Madrid Deep Space Communications Complex in Robledo de Chavela, Spain.
- ID:
- ivo://CDS.VizieR/J/A+A/551/A113
- Title:
- Spectrum of VY CMa in 220.65-224.25GHz range
- Short Name:
- J/A+A/551/A113
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the first detection of pure rotational transitions of TiO and TiO2 at (sub-)millimeter wavelengths towards the red supergiant VYCMa. A rotational temperature, Trot, of about 250K was derived for TiO2. Although Trot was not well constrained for TiO, it is likely somewhat higher than that of TiO2. The detection of the Ti oxides confirms that they are formed in the circumstellar envelopes of cool oxygen-rich stars and may be the "seeds" of inorganic-dust formation, but alternative explanations for our observation of TiO and TiO2 in the cooler regions of the envelope cannot be ruled out at this time. The observations suggest that a significant fraction of the oxides is not converted to dust, but instead remains in the gas phase throughout the outflow.