- ID:
- ivo://CDS.VizieR/J/ApJ/854/124
- Title:
- The Megamaser Cosmology Project. X.
- Short Name:
- J/ApJ/854/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution (submas) Very Long Baseline Interferometry maps of nuclear H_2_O megamasers for seven galaxies. In UGC 6093, the well-aligned systemic masers and high-velocity masers originate in an edge-on, flat disk and we determine the mass of the central supermassive black holes (SMBH) to be M_SMBH_=2.58x10^7^M_{sun}_ (+/-7%). For J1346+5228, the distribution of masers is consistent with a disk, but the faint high-velocity masers are only marginally detected, and we constrain the mass of the SMBH to be in the range (1.5-2.0)x10^7^M_{sun}_. The origin of the masers in Mrk 1210 is less clear, as the systemic and high-velocity masers are misaligned and show a disorganized velocity structure. We present one possible model in which the masers originate in a tilted, warped disk, but we do not rule out the possibility of other explanations including outflow masers. In NGC 6926, we detect a set of redshifted masers, clustered within a parsec of each other, and a single blueshifted maser about 4.4pc away, an offset that would be unusually large for a maser disk system. Nevertheless, if it is a disk system, we estimate the enclosed mass to be M_SMBH_<4.8x10^7^M_{sun}_. For NGC 5793, we detect redshifted masers spaced about 1.4pc from a clustered set of blueshifted features. The orientation of the structure supports a disk scenario as suggested by Hagiwara+ (2001ApJ...560..119H). We estimate the enclosed mass to be M_SMBH_<1.3x10^7^M_{sun}_. For NGC 2824 and J0350-0127, the masers may be associated with parsec- or subparsec-scale jets or outflows.
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1492. The MERLIN Archive
- ID:
- ivo://CDS.VizieR/B/merlin
- Title:
- The MERLIN Archive
- Short Name:
- B/merlin
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This database contains a log of MERLIN archive data since 1992 which have been partially reduced and are electronically available. It is managed and updated by the MERLIN staff. All data are taken using a single IF and correlated using 2-bit digitisation.
- ID:
- ivo://CDS.VizieR/VIII/52B
- Title:
- The MIT-Green Bank 5GHz Survey
- Short Name:
- VIII/52B
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The MIT-Green Bank 5GHz survey catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope (Bennett et al., 1986ApJS...61....1B (MG1); Langston et al., 1990ApJS...72..621L (MG2); Griffith et al., 1990ApJS...74..129G (MG3); Griffith et al. 1991ApJS...75..801G (MG4)). The sky coverage of the various surveys is: 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1; 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2; 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3; and 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4; where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365MHz survey (Douglas et al. 1980), and for MG1-MG4 sources also identified in the NRAO 1400MHz Survey (Condon and Broderick 1985).
- ID:
- ivo://CDS.VizieR/J/A+AS/99/545
- Title:
- The Miyun 232 MHz survey. I
- Short Name:
- J/A+AS/99/545
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains a new meter-wave survey of the sky region north of declination 30{deg}, carried out with the Miyun 232 MHz SSSynthesis Radio Telescope (MSRT) at HPBW 3.8' x 3.8' cosec(dec). Results from two fields are presented here; the fields are 8 degrees on a side, centered at 0041+41.2 and 0700+35.0. The accuracy of flux determination is limited by background fluctuation which is about 30 mJy. The catalogue is complete for sources with flux greater than 0.25 Jy. The total number of sources listed in the catalogue is 687.
1495. The mJIVE-20 catalog
- ID:
- ivo://CDS.VizieR/J/AJ/147/14
- Title:
- The mJIVE-20 catalog
- Short Name:
- J/AJ/147/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the description and early results of the mJy Imaging VLBA Exploration at 20cm (mJIVE-20). mJIVE-20 is a large project on the Very Long Baseline Array which is systematically inspecting a large sample of mJy radio sources, pre-selected from the Faint Images of the Radio Sky at Twenty cm (FIRST) survey made with the Very Large Array, to identify any compact emission that may be present. The survey is being undertaken using filler time on the VLBA, which utilizes short segments scheduled in bad weather and/or with a reduced number of antennas, during which no highly rated science projects can be scheduled. The newly available multifield capability of the VLBA makes it possible for us to inspect of the order of 100 sources per hour of observing time with a 6.75{sigma} detection sensitivity of approximately 1mJy/beam. The results of the mJIVE-20 survey are made publicly available as soon as the data are calibrated. After 18 months of observing, over 20000 FIRST sources have been inspected, with 4336 very long baseline interferometry detections. These initial results suggest that within the range 1-200mJy, fainter sources are somewhat more likely to be dominated by a very compact component than brighter sources. Over half of all arcsecond-scale mJy radio sources contain a compact component, although the fraction of sources that are dominated by milliarcsecond scale structure (where the majority of the arcsecond scale flux is recovered in the mJIVE-20 image) is smaller at around 30%-35%, increasing toward lower flux densities. Significant differences are seen depending on the optical classification of the source. Radio sources with a stellar/point-like counterpart in the Sloan Digital Sky Survey (SDSS) are more likely to be detected overall, but this detection likelihood appears to be independent of the arcsecond-scale radio flux density. The trend toward higher radio compactness for fainter sources is confined to sources that are not detected in SDSS or that have counterparts classified as galaxies. These results are consistent with a unification model of active galactic nuclei in which less luminous sources have on average slower radio jets, with lower Doppler suppression of compact core emission over a wider range of viewing angles.
- ID:
- ivo://CDS.VizieR/J/AJ/131/100
- Title:
- The Molonglo Southern 4Jy sample. I
- Short Name:
- J/AJ/131/100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have defined a complete sample of 228 southern radio sources at 408MHz with integrated flux densities S(408)>4.0Jy, Galactic latitude |b|>10{deg}, and declination -85{deg}<{delta}<-30{deg}. The main finding survey used was the Molonglo Reference Catalogue (Cat. <VIII/16>). Sources in the sample were imaged at 843MHz with the Molonglo Observatory Synthesis Telescope to obtain positions accurate to about 1", as well as flux densities and angular sizes.
- ID:
- ivo://CDS.VizieR/J/AJ/131/114
- Title:
- The Molonglo Southern 4Jy sample. II
- Short Name:
- J/AJ/131/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Of the 228 sources in the Molonglo Southern 4Jy sample (MS4, Cat. J/AJ/131/100), the 133 with angular sizes <35" have been imaged at 5GHz at 2"-4" resolution with the Australia Telescope Compact Array. More than 90% of the sample has been reliably optically identified, either on the plates of the UK Schmidt Southern Sky Survey or on R-band CCD images made with the Anglo-Australian Telescope.
1498. The MORX catalogue
- ID:
- ivo://CDS.VizieR/V/148
- Title:
- The MORX catalogue
- Short Name:
- V/148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This automated catalogue combines all the largest published optical, radio and X-ray sky catalogues to find probable radio/X-ray associations to optical objects, plus double radio lobes, using uniform processing against all input data. The total count is 1002855 optical objects so presented. Each object is displayed with J2000 astrometry, optical and radio/X-ray identifiers, red and blue photometry, and calculated probabilities and optical field solutions of the associations. This is the third and final edition of this method.
- ID:
- ivo://CDS.VizieR/J/A+A/588/A141
- Title:
- The MWA view of Fermi blazars
- Short Name:
- J/A+A/588/A141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. We characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. We cross-correlated the 6100-deg^2^ Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detected by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20GHz catalogue.
- ID:
- ivo://CDS.VizieR/J/MNRAS/392/733
- Title:
- The NEWPS catalog from WMAP 5-yr survey
- Short Name:
- J/MNRAS/392/733
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have analysed the efficiency in source detection and flux density estimation of blind and non-blind detection techniques exploiting the MHW2 filter applied to the Wilkinson Microwave Anisotropy Probe (WMAP) 5-yr maps. A comparison with the AT20G bright source sample, with a completeness limit of 0.5Jy and accurate flux measurements at 20GHz, close to the lowest frequency of WMAP maps, has allowed us to assess the completeness and the reliability of the samples detected with the two approaches, as well as the accuracy of flux and error estimates, and their variations across the sky.
