Search

Start Over Subject radio astronomy
1051. Molecular line survey towards UC HII
ID:
ivo://CDS.VizieR/J/A+AS/133/29
Title:
Molecular line survey towards UC HII
Short Name:
J/A+AS/133/29
Date:
21 Oct 2021
Publisher:
CDS
Description:
The tables give identifications for molecular lines detected in the survey of ultracompact HII regions. The survey covers 14 sources: G5.89, G9.62, G10.30, G10.47, G12.21, G13.87, G29.96, G31.41, G34.26, G43.89, G45.12, G45.45, G45.47, and G75.78. For each source, we observed up to ten 1~GHz bands between 200 and 350~GHz, covering lines of more than 30 species including multiple transitions of CO isotopes, CH_3_OH, CH_3_CCH, CH_3_CN and HCOOCH_3, and sulphuretted molecules. The tables give the measured line parameters of observed frequency {nu}(obs), peak temperature T_R_^*^ and linewidth {Delta}{nu}_1/2_ for each line. Each independent detection of a particular line is given. The species, transition, rest frequency and upper level energy (E_u_/k) are given for identified lines.
1052. Molecular maps of NGC1333
ID:
ivo://CDS.VizieR/J/A+A/606/A123
Title:
Molecular maps of NGC1333
Short Name:
J/A+A/606/A123
Date:
21 Oct 2021
Publisher:
CDS
Description:
Are the initial conditions for clustered star formation the same as for non-clustered star formation? To investigate the initial gas properties in young proto-clusters we carried out a comprehensive and high-sensitivity study of the internal structure, density, temperature, and kinematics of the dense gas content of the NGC1333 region in Perseus, one of the nearest and best studied embedded clusters. The analysis of the gas velocities in the Position-Position-Velocity space reveals an intricate underlying gas organization both in space and velocity. We identified a total of 14 velocity-coherent, (tran-)sonic structures within NGC1333, with similar physical and kinematic properties than those quiescent, star-forming (aka fertile) fibers previously identified in low-mass star-forming clouds. These fibers are arranged in a complex spatial network, build-up the observed total column density, and contain the dense cores and protostars in this cloud. Our results demonstrate that the presence of fibers is not restricted to low-mass clouds but can be extended to regions of increasing mass and complexity. We propose that the observational dichotomy between clustered and non-clustered star-forming regions might be naturally explained by the distinct spatial density of fertile fibers in these environments.
1053. Molecules in O- and C-rich envelopes
ID:
ivo://CDS.VizieR/J/A+A/285/247
Title:
Molecules in O- and C-rich envelopes
Short Name:
J/A+A/285/247
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations of 10 microwave transitions of the molecules SiO, HCN, HNC, SiS, HC_3_N, CS, SO, and ^13^CO are presented in a total sample of 47 evolved stars. The studied sources are mainly O- and C-rich standard AGB stars, as well as O-rich red supergiants, S-type stars, protoplanetary nebulae and detached envelopes. We also take into account observations of these transitions, as well as of ^12^CO J=1-0, from the literature. The observations were carried out during May and September 1991 and June 1992 with the IRAM 30-m radiotelescope at Pico de Veleta (Spain); the resolution is 1MHz for 3mm data (100GHz) and 2 MHz for 2 and 1mm data (150 to 300GHz).
1054. Molonglo deep sky survey of radio sources
ID:
ivo://CDS.VizieR/VIII/46
Title:
Molonglo deep sky survey of radio sources
Short Name:
VIII/46
Date:
21 Oct 2021
Publisher:
CDS
Description:
The observations for the MDS1 were made in Sep. 1973 over a period of 16 days, and consist of drift scans with the telescope set to one declination number (-20 and -62{deg}) during the transit of the RA range of the survey, and scanning a long narrow strip of sky. The MDS2 results from observations made in 1978 with the same telescope working at its maximum sensitivity
1055. Molonglo Reference Catalog of Radio Sources
ID:
ivo://CDS.VizieR/VIII/2
Title:
Molonglo Reference Catalog of Radio Sources
Short Name:
VIII/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Molonglo Reference Catalog of Radio Sources results from a 408-MHz survey observations made with the Molonglo Radio Telescope (Australia) between 1968 and 1978. The survey covers 7.85sr of the sky between the declinations -85{deg} and +18{deg}, excluding the strip of the galactic plane (|b|<=3{deg}). The nominal beamwidth is 2.62arcmin in right ascension and 2.86sec({delta}+35.5)arcmin in declination. There are 7347 sources with flux density S>=1Jy, at which level the catalogue is substantially complete. A new version of the catalog has been done in 1990 (Cat. VIII/16).
1056. Molonglo Reference Catalogue of Radio Sources
ID:
ivo://CDS.VizieR/VIII/16
Title:
Molonglo Reference Catalogue of Radio Sources
Short Name:
VIII/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
"408-MHz survey observations made with the Molonglo Radio Telescope have been used to prepare a catalogue of 12 141 discrete sources of listed flux density >= 0.7 Jy. The survey covers 7.85 sr of the sky defined by +18.5 (deg) >= dec(1950) >= -85.0 (deg), mod(b) >= 3 (deg). A few sources beyond the declination limits are also included. The catalogue comprises celestial coordinates with standard error typically lying between 3 and 10 arcsec and 408-MHz flux densities with standard error typically lying between 4 and 10 per cent. Galactic coordinates, notes on source morphology and cross-references to the Parkes Catalogues are included. The overall source density is 1500/sr, corresponding to 0.001 per beam area. There are 7347 sources of listed flux density >= 1.00 Jy, at which level the catalogue is substantially complete. The reliability is believed to be better than 99.9 per cent." The MRC was re-issued in 1990 with the original B1950 coordinates supplemented by J2000 values, and an additional cross-reference flag `J' added to denote (extended) sources imaged at 843-MHz by P.A. Jones. No other alterations were made to the original release. The MRC is now available on 5.25 inch, 1.2 Mbyte MS-DOS (IBM) floppy disk (0.5 inch magnetic tape is also available, but is not the preferred medium). In the floppy disk format, simple software is provided to facilitate use of the catalogue on a PC computer.
1057. Monitoring compact radio sources at 2.5 + 8.2GHz
ID:
ivo://CDS.VizieR/J/ApJS/136/265
Title:
Monitoring compact radio sources at 2.5 + 8.2GHz
Short Name:
J/ApJS/136/265
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present light curves for 149 sources monitored with the Green Bank Interferometer. The light curves are at two radio frequencies (approximately 2.5 and 8.2GHz) and range from 3 to 15yr in length, covering the interval 1979-1996, and have a typical sampling of one flux density measurement every 2 days. Observations were made on a 2.4km baseline. Dual circular polarization was recorded over a 35MHz bandwidth at two frequencies in the S and X frequency bands. Until 1989 August (1989.7), the frequencies were 2.7GHz (S band) and 8.1GHz (X band); in 1989 September cryogenic receivers were installed, and the frequencies changed to 2.25GHz (S band) and 8.3GHz (X band).
1058. Monitoring of Mrk 421 at 15 and 24 GHz
ID:
ivo://CDS.VizieR/J/A+A/545/A117
Title:
Monitoring of Mrk 421 at 15 and 24 GHz
Short Name:
J/A+A/545/A117
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-resolution radio observations are ideal for constraining the value of physical parameters in the inner regions of active-galactic-nucleus jets and complement results on multiwavelength (MWL) observations. This study is part of a wider multifrequency campaign targeting the nearby TeV blazar Markarian 421 (z=0.031), with observations in the sub-mm (SMA), optical/IR (GASP), UV/X-ray (Swift, RXTE, MAXI), and {gamma} rays (Fermi-LAT, MAGIC, VERITAS). We investigate the jet's morphology and any proper motions, and the time evolution of physical parameters such as flux densities and spectral index. The aim of our wider multifrequency campaign is to try to shed light on questions such as the nature of the radiating particles, the connection between the radio and {gamma}-ray emission, the location of the emitting regions and the origin of the flux variability.
1059. Morphologies of selected AGN
ID:
ivo://CDS.VizieR/J/AJ/140/533
Title:
Morphologies of selected AGN
Short Name:
J/AJ/140/533
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the optical morphologies of candidate active galaxies identified at radio, X-ray, and mid-infrared wavelengths. We use the Advanced Camera for Surveys General Catalog (ACS-GC) to identify 372, 1360, and 1238 active galactic nucleus (AGN) host galaxies from Very Large Array, XMM-Newton, and Spitzer Space Telescope observations of the COSMOS field, respectively. We investigate both quantitative (GALFIT) and qualitative (visual) morphologies of these AGN host galaxies, split by brightness in their selection band.
1060. Morphology for groups in the FIRST database
ID:
ivo://CDS.VizieR/J/ApJS/194/31
Title:
Morphology for groups in the FIRST database
Short Name:
J/ApJS/194/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
The morphology of selected groups of sources in the Faint Images of the Radio Sky at Twenty Centimeters (FIRST) survey and catalog is examined. Sources in the FIRST catalog (2003 April release, 811117 entries) were sorted into singles, doubles, triples, and groups of higher-count membership based on a proximity criteria. The 7106 groups with four or more components were examined individually for bent types including, but not limited to, wide-angle tail and narrow-angle tail types. In the process of this examination, ring, double-double, X-shaped, hybrid morphology, giant radio sources, and the herein described W-shaped and tri-axial morphology systems were also identified. For the convenience of the reader separate tables for distinctive types were generated. A few curiosities were found. For the 16950 three-component groups and 74788 two-component groups, catalogs with probability estimates for bent classification, as determined by pattern recognition techniques, are presented.