- ID:
- ivo://CDS.VizieR/J/A+A/391/887
- Title:
- Redshifts in the Hydra/Antlia Extension
- Short Name:
- J/A+A/391/887
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of our program to map the large-scale distribution of galaxies behind the Milky Way, we used the Parkes 210 ft (64m) radio telescope for pointed HI observations of a sample of low surface-brightness (due to heavy obscuration) spiral galaxies selected from the deep optical Zone of Avoidance (ZOA) galaxy catalog in the Hydra/Antlia region (Kraan-Korteweg, 2000, Cat. <J/A+AS/141/123>). Searching a simultaneous velocity range of either 300 to 5500km/s or 300 to 10500km/s to an rms level of typically 2-4mJy resulted in detections in 61 of the 139 pointings, leading to a total of 66 detections (an additional detection was made in a reference position, and two other pointings revealed two and four independent signals respectively). Except for 2 strong HI emitters identified in the shallow Zone of Avoidance HI survey (Henning et al., 2000AJ....119.2686H), all HI detections are new.
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- ID:
- ivo://CDS.VizieR/J/A+A/642/A153
- Title:
- SAGAN. I. New sample & multi-wavelength studies
- Short Name:
- J/A+A/642/A153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a project called SAGAN, which is dedicated solely to the studies of relatively rare megaparsec-scale radio galaxies in the Universe, called giant radio galaxies (GRGs). We have identified 162 new GRGs primarily from the NVSS with sizes ranging from ~0.71Mpc to 2.82Mpc in the redshift range of ~0.03-0.95, of which 23 are hosted by quasars (giant radio quasars, GRQs). As part of the project SAGAN, we have created a database of all known GRGs, the GRG catalogue, from the literature (including our new sample); it includes 820 sources. For the first time, we present the multi-wavelength properties of the largest sample of GRGs. Our results establish that the distributions of the radio spectral index and the black hole mass of GRGs do not differ from the corresponding distributions of normal-sized radio galaxies (RGs). However, GRGs have a lower Eddington ratio (ER) than RGs. Using the mid-infrared data, we classified GRGs in terms of their accretion mode: either a high-power radiatively efficient high-excitation state, or a radiatively inefficient low-excitation state. We find that GRGs in high-excitation state statistically have larger sizes, stronger radio power, jet kinetic power, and higher ER than those in low-excitation state. Our analysis reveals a strong correlation between the ER and the scaled jet kinetic power, which suggests a disc-jet coupling. Our environmental study reveals that ~10% of all GRGs may reside at the centres of galaxy clusters, in a denser galactic environment, while the majority appears to reside in a sparse environment. We find that the probability of BCG as a GRG is quite low. We present new results for GRGs that range from black hole mass to large-scale environment properties. We discuss their formation and growth scenarios, highlighting the key physical factors that cause them to reach their gigantic size.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/70.264
- Title:
- Sample of 877 blazars
- Short Name:
- J/other/AstBu/70
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the synchrotron component of the spectral energy distribution on the sample of 877 blazars using ASDC SED Builder Tool with available broadband data from the literature. Our sample includes 423 flat-spectrum radio sources (FSRQs), 361 BL Lac objects and candidates, and 93 blazars of uncertain type. We have made an estimation of the synchrotron peak frequency for the 875 objects and further classified them as high, intermediate and low synchrotron peaked sources (HSPs/ISPs/LSPs). For each source NVSS name (RA (HHMMSS) and DEC (DDMMSS) for the J2000.0 epoch), alias, redshift, R band magnitude, synchrotron peak frequency, correlation coefficient, flux density at 4.8GHz, SED class, blazar type and selection method are presented.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/68.262
- Title:
- Sample of 467 GPS candidates
- Short Name:
- J/other/AstBu/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a comprehensive analysis of continuous radio spectra of a sample of Gigahertz-Peaked Spectrum (GPS) sources are reported. The sources are selected from a flux-density-complete sample (S more or equal 200mJy at 4.8 or 5GHz) using multifrequency measurements of the RATAN-600 radio telescope and data from the CATS astrophysical catalogs support system. The analysis revealed a very small number (1-2%) of "classical" GPS objects, which is significantly less than the expected fraction of 10%. GPS galaxies are found to have narrower and steeper radio spectra than quasars. The low-frequency part of the spectrum is seen to become steeper with increasing redshift. Galaxies and quasars at the same z have comparable angular sizes, whereas their luminosities may differ by one order of magnitude. At large redshifts there is a deficit of objects with low (several GHz) peak frequencies. The number of GPS galaxies decreases sharply with redshift, and most of them are found at z between 0.01 and 1.81. GPS quasars are found at large redshifts, from 0.11 to 3.99. A quarter of the sample consists of blazars whose spectra may temporarily have a convex shape when the object is in active state.
- ID:
- ivo://CDS.VizieR/J/A+AS/147/187
- Title:
- Second list of the Karachentsev catalog
- Short Name:
- J/A+AS/147/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table2 presents the results of HI observations of 78 'nearby dwarf galaxies' from Karachentseva et al. (1999A&AS..135..221K) obtained with the 100-m radio telescope at Effelsberg. This survey covers an area limited by R.A.[14h,23h30] and Dec[-20d,+60d] including the nearest cosmic void : R.A.[18h38m], Dec[+18d], V_0_<1500km/s.
- ID:
- ivo://CDS.VizieR/J/A+AS/116/157
- Title:
- SEST obs. of extragalactic radiosources
- Short Name:
- J/A+AS/116/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Flux densities of 155 extragalactic radio sources observed with the SEST telescope at 3mm and 1.3mm are presented. The observations were performed from October 1987 to June 1994. In addition to the flux density tables we have plotted the flux density curves for some of the most frequently observed sources.
- ID:
- ivo://CDS.VizieR/J/ApJS/192/15
- Title:
- Seven-year WMAP catalog
- Short Name:
- J/ApJS/192/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination outside of the updated (KQ85y7) foreground mask. We place a 15uK upper bound on rms foreground contamination in the cleaned maps used for cosmological analysis. Further, the cleaning process requires only three power-law foregrounds outside of the mask. We find no evidence for polarized foregrounds beyond those from soft (steep-spectrum) synchrotron and thermal dust emission; in particular we find no indication in the polarization data of an extra "haze" of hard synchrotron emission from energetic electrons near the Galactic center. We provide an updated map of the cosmic microwave background (CMB) using the internal linear combination method, updated foreground masks, and updates to point source catalogs using two different techniques. With additional years of data, we now detect 471 point sources using a five-band technique and 417 sources using a three-band CMB-free technique. In total there are 62 newly detected point sources, a 12% increase over the five-year release.
- ID:
- ivo://CDS.VizieR/J/AJ/125/2411
- Title:
- SIRTF First-Look Survey
- Short Name:
- J/AJ/125/2411
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The First-Look Survey (FLS) of the Space Infrared Telescope Facility (SIRTF) will cover about 5deg^2^ centered on J2000.0 (17:18+59:30) in order to characterize the extragalactic infrared sky 2 orders of magnitude deeper than the IRAS survey. We expect that most of the FLS far-infrared ({lambda} = 160, 70, and 24 {mu}m) sources will be star-forming galaxies obeying the very tight far-infrared/radio correlation and will be continuum radio sources with flux densities S>~100{mu}Jy at {nu}=1.4GHz. Conversely, radio sources stronger than 100{mu}Jy are usually powered by star-forming galaxies, plus some active galactic nuclei, and most should be detectable by the SIRTF FLS. Thus, a sensitive radio survey can be used to select and identify most of the SIRTF FLS source population before launch. We used the B configuration of the VLA to make an image of the FLS area at {nu}=1.4GHz with {sigma}=~23{mu}Jy/beam rms fluctuations, {theta}=5'' resolution, and {sigma}_{alpha}_=~{sigma}_{delta}_=~0.5'' rms uncertainties in right ascension and declination. The resulting radio image and catalog of 3565 radio components with peak flux densities Sp>=5{sigma}=115{mu}Jy/beam have been released via the Web to expedite follow-up optical identification and spectroscopy.
- ID:
- ivo://CDS.VizieR/J/ApJS/80/137
- Title:
- Southern Extragalactic Radio Sources
- Short Name:
- J/ApJS/80/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains a list of 384 extragalactic radio sources south of declination -30{deg} which have been imaged with the Molonglo Observatory Synthesis Telescope (MOST) at 843 MHz with a HPBW of 44" x 44" cosec(dec). The sample includes those sources noted in the Molonglo Reference Catalog (MRC) (Cat.<VIII/16>) as extended (larger than 1'), as well as those noted as multiple (within 8' of another ssource and possibly related). The sample is representative of the strong extended extragalactic radio sources of the southern sky, but is not statistically complete. Positions, flux densities, and sizes are given for all sources, and those sources which have been confirmed as extended MRC sources are flagged. In addition, optical positions, magnitudes, redshifts, and identifications are given for 201 of the sources. These data were originally published in two tables which have been merged in this version.
- ID:
- ivo://CDS.VizieR/VIII/74A
- Title:
- SPECFIND Catalog of radio continuum spectra
- Short Name:
- VIII/74A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SPECFIND is a new tool to extract cross-identifications and radio continuum spectra from radio catalogues contained in the VIZIER database of the CDS. It is designed to handle radio surveys of very different resolutions and sensitivities. Power laws are fitted to the radio spectra, resulting in the determination of a power law slope and a zero-point. SPECFIND has been applied to 22 survey catalogues at 11 different frequencies (159 - 8400 MHz) containing a total of 3.5 million sources, leading to 757894 independent radio cross-identifications and 66866 independent radio spectra with more than two independent frequencies. The code was tested and its results validated by a comparison between the spectral indices found by SPECFIND and those determined by other authors. The determined spectral indices have an error of about +/-0.3. Negative spectral indices have smaller errors, while the error of positive spectral indices can be larger, mainly because of the occurrence of a peak in the spectrum. The code is quite rapid (less than 3 hr running time on a standard PC for 3.5 million sources) and since it is written in C, it can be run on virtually all PCs with at least 512~MB RAM. It produces an output of variable format that can be adapted easily to the purpose of the user. The results of the spectrum identification process are provided as a master table, where a spectrum is attached to each radio source. Due to the SPECFIND algorithm, different radio components of the same physical source can have somewhat different slopes and zero-points. The SPECFIND subdirectory contains the code (in C) and the data used to generate the catalogue, as well as a user manual (manual.ps). For compilation please IMPERATIVELY read the README file stored in the SPECFIND subdirectory.