- ID:
- ivo://CDS.VizieR/J/ApJS/75/801
- Title:
- MGIV (Fourth MIT-Green Bank) 5GHz Survey
- Short Name:
- J/ApJS/75/801
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The MIT-Green Bank IV (MG IV) 5 GHz survey covers 0.504 sr of sky in the right ascension range 15.5 to 2.5 hours, between +37.00 and +50.98 degrees declination (B1950). The final MG IV catalog contains 3427 sources detected with a signal-to-noise ratio greater than 5. The catalog was produced from two separate north and south surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope. The north survey was produced from data collected while scanning the telescope north from +39.0 to +50.98 degrees declination and the south survey from data collected from scans from +48.98 to +37.00 degrees declination. The completeness and reliability of the final source list is checked by examination of north and south source lists in a twice observed comparison region, lying between +39.15 and +48.83 degrees declination and excluding the area between +/-10 degrees Galactic latitude. The comparison region covers 0.270 sr of sky and contains 1094 sources. In this region, the MG IV catalog contains 423 sources brighter than 90 mJy and is shown to be 99.1 +/- 1.2% complete at this flux density level. Spectral indices are computed for sources identified in the NRAO 1400 MHz Survey (published by Condon and Broderick in 1985). A comparison of the spectral index distributions between +/- 10 and outside of +/- 10 degrees Galactic latitude is presented.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/402/2792
- Title:
- 1388MHz ATLBS Low-Brightness Survey
- Short Name:
- J/MNRAS/402/2792
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a radio survey carried out with the Australia Telescope Compact Array. A motivation for the survey was to make a complete inventory of the diffuse emission components as a step towards a study of the cosmic evolution in radio source structure and the contribution from radio-mode feedback on galaxy evolution. The Australia Telescope Low-Brightness Survey (ATLBS) at 1388MHz covers 8.42deg^2^ of the sky in an observing mode designed to yield images with exceptional surface brightness sensitivity and low confusion. The survey was carried out in two adjacent regions on the sky centred at 00:35:00-67:00:00 and 00:59:17=-67:00:00 (J2000.0). The ATLBS radio images, made with 0.08mJy/beam rms noise and 50arcsec beam, detect a total of 1094 sources with peak flux exceeding 0.4mJy/beam. The ATLBS source counts were corrected for blending, noise bias, resolution and primary beam attenuation; the normalized differential source counts are consistent with no upturn down to 0.6mJy.
- ID:
- ivo://CDS.VizieR/J/A+AS/58/1
- Title:
- 1412 MHz catalogue of Westerbork survey. I.
- Short Name:
- J/A+AS/58/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A radio survey has been conducted with the Westerbork Synthesis Radio Telescope for nine fields in four high latitude areas for which deep, multicolor Kitt Peak 4-m plates are available. A total of 471 sources are tabulated; 306 of these form a well defined, complete sample. The influence of the selection criteria on sample completeness is discussed. Angular size distribution has been precisely derived, in virtue of the 3 km resolution obtainable with the present instrument, and a smaller fraction of sources larger than about 20arcsec is noted for the 1-10mJy range than for the 10-100mJy. The 1412MHz source counts are consistent at different cutoff levels, showing that the statistical corrections for population and resolution bias are reliable. The present counts are consistent with previous 1.4GHz counts, which are here given for the 1-100000mJy flux range.
- ID:
- ivo://CDS.VizieR/J/A+AS/58/39
- Title:
- 1412 MHz catalogue of Westerbork survey. II
- Short Name:
- J/A+AS/58/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A deep multicolor optical identification program is presented for a complete sample of 302 radio sources that were observed with the Westerbork Synthesis Radio Telescope within 5.52{deg}^2^ down to S_1.4GHz_>~0.6mJy (5{sigma}). Optical identifications are made from multicolor prime focus plates taken with the Kitt Peak 4 meter telescope in the passbands U,J,F and N with approximate respective limiting magnitudes of ~23.3, 23.7, 22.7 and 21.1. The astrometry has systematic errors smaller than 0.2"-0.3", while the random errors are of order 0.4". The agreement between the radio and optical coordinate frames is on average better than 0.25". Identifications are based on positional coincidence using the likelihood ratio method. For 171 out of the 302 radio sources likely identifications are proposed with an a posteriori identification percentage of 53%, 14 expected spurious objects (or 5% of all radio sources), while not more than 4 identifications have been missed. The sample reliability is 92% and its completeness 98%. About 20% of the identifications are stellar objects, the remaining have extended images or are too faint to be classified. About 15% of the identifications appear in possible clusters. The identification statistics are roughly constant from field to field, except for the Hercules 2 field which has an unusually high identification fraction (74%). The identification fraction is presented as a function of 21 cm flux density and limiting magnitude, and amounts to 15% for 1<~S_1.4GHz_<~100mJy down to the Palomar Sky Survey limit and 29% down to the effective 48" Schmidt limit. For S_1.4_<~100mJy the identification fraction remains roughly constant with flux density, contrary to the prediction of higher fractions by some models for cosmological evolution. The magnitude distributions for galaxies plus objects of unknown type generally increase towards fainter magnitudes; the quasar magnitude distributions are also increasing but not as steeply as for the radio galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/251/330
- Title:
- 8400MHz flux densities for Southern sources
- Short Name:
- J/MNRAS/251/330
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+AS/65/485
- Title:
- 22MHz flux densities of radio sources
- Short Name:
- J/A+AS/65/485
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- table1 is a compilation of the flux densities at 22.25MHz for 395 sources, derived from three or more observations of each source. The source were measured over a period of several years with the T-shaped radiotelescope at the Dominion Astrophysical Observatory. The Note: This catalogue supersedes Cat. <J/AJ/74/366>
- ID:
- ivo://CDS.VizieR/J/MNRAS/329/775
- Title:
- 330MHz flux of 4 SNR near Galactic Centre
- Short Name:
- J/MNRAS/329/775
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have observed two fields - Field I (l=3.2{deg}, b=1.0{deg}) and Field II (l=356.8{deg}, b=-0.1{deg}) - with the Giant Metrewave Radio Telescope (GMRT) at 330MHz. In the first field, we have studied the candidate supernova remnant (SNR) G3.1-0.6 and, based on its observed morphology, spectral index and polarization, confirmed it to be an SNR. We find this supernova to have a double ring appearance with a strip of emission on its western side passing through its centre. We have discovered two extended curved objects in the second field, which appears to be part of a large shell-like structure. It is possibly the remains of an old supernova in the region. Three suspected SNRs, G356.3-0.3, G356.6+0.1 and G357.1-0.2, detected in the MOST 843-MHz survey of the GC region appear to be located on this shell-like structure. While both G356.3-0.3 and G356.6+0.1 seem to be parts of this shell, G357.1-0.2, which has a steeper spectrum above 1GHz, could be a background SNR seen through the region. Our Hi absorption observation towards the candidate SNR G357.1-0.2 indicates that it is at a distance of more than 6kpc from us.
- ID:
- ivo://CDS.VizieR/J/other/AuJPA/14.77
- Title:
- 408MHz galactic radio sources
- Short Name:
- J/other/AuJPA/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Contour maps of 58 regions are presented showing 408 MHz radioisophotes for over 200 galactic radio sources. Positions and integrated flux densities are listed for all the sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/390/741
- Title:
- 150MHz GMRT survey in Eridanus
- Short Name:
- J/MNRAS/390/741
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a 150MHz survey of a field centred on {epsilon} Eridani, undertaken with the Giant Metrewave Radio Telescope (GMRT). The survey covers an area with a diameter of ~2{deg}, has a spatial resolution of ~30arcsec and a noise level of {sigma}=3.1mJy at the pointing centre. These observations provide a deeper and higher resolution view of the 150MHz radio sky than the 7C survey (although the 7C survey covers a much larger area). A total of 113 sources were detected, most are point-like, but 20 are extended. We present an analysis of these sources, in conjunction with the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) telescope Sky Survey (NVSS) (at 1.4GHz) and VLA Low-frequency Sky Survey (VLSS) (at 74MHz). This process allowed us to identify five Ultra-Steep Spectrum (USS) radio sources that are candidate high-redshift radio galaxies (HzRGs). In addition, we have derived the dN/dS distribution for these observations and compare our results with other low-frequency radio surveys.
- ID:
- ivo://CDS.VizieR/J/MNRAS/421/1644
- Title:
- 843MHz MOST ATLAS catalogue
- Short Name:
- J/MNRAS/421/1644
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At the faintest radio flux densities (S1.4<10mJy), conflicting results have arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610MHz) and, for example, 1.4GHz. We present a new catalogue of 843-MHz radio sources in the European Large Area ISO Survey-South 1 field, which contains the sources, their Australia Telescope Large Area Survey (ATLAS) counterparts and the spectral index distribution of the sources as a function of flux density.
