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- ID:
- ivo://CDS.VizieR/J/other/AstBu/69.266
- Title:
- RATAN-600 flux densities of 37 blazars
- Short Name:
- J/other/AstBu/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the correlation between the emission from the broad-line region (BLR) and the emission in other wavelength ranges (from radio to x-ray) for the sample of 37 blazars (25 flat-spectrum radio quasars (FSRQs) and 10 BL Lac blazars). Studying the relation between luminosities in various wavebands and the BLR luminosity is an effective method to examine the connection between the accretion rate and the luminosity of the jet.We used simultaneous RATAN-600measurements of blazar flux densities at six frequencies: 1.1, 2.3, 4.8, 7.7, 11.2, and 21.7GHz. The observational data from other bands was taken from the literature. To determine the effect produced by the state of the object on the correlation, for the radio data we used the measurements obtained with the RATAN-600 in two states-namely, the maximum and minimum flux density values.We show that at some frequencies of the radio band, there exists a correlation of emission with the emission in the BLR for two types of blazars. In the FSRQ and BL Lac blazars, the correlation between the flux from the BLR and the flux in the radio band is indistinguishable in all cases, except for the case when a strong flux density variation was considered for the BL Lac-type of blazars (tens of percent). At the same time, the levels of significance for BL Lac (at certain frequencies p is worse than 0.05) in the active state indicate only the probable presence of connection. On the example of the sample, we show that the variability of emission significantly affects the level of correlation. Our results are consistent with the theoretical predictions about the close relationship of the accretion disk and the jet in blazars.
- ID:
- ivo://CDS.VizieR/J/A+A/370/78
- Title:
- RATAN-600 NCP bright radio sources
- Short Name:
- J/A+A/370/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A survey of the North Celestial Pole region using the RATAN-600 radio telescope at five frequencies in the range 2.3 to 21.7 GHz is described. Sources were chosen from the NVSS catalogue. The flux densities of 171 sources in the Declination range +75{deg} to +88{deg} are presented; typical flux density errors are 5-10 percent including calibration errors. About 20 percent of the sources have flat spectra or a flat component.
- ID:
- ivo://CDS.VizieR/J/other/BSAO/40.5
- Title:
- RATAN-600 RC radio sources
- Short Name:
- J/other/BSAO/40.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the RATAN-600 radio telescope for picking up the most distant objects in the Universe. As a first step, about 100 steep spectrum FRII radio galaxies (SS FRII RG) from the RATAN-600 RC catalog (Parijskij et al., 1991, Cat. <J/A+AS/87/1>; 1992A&AS...96..583P) were mapped by the VLA and identified with optical objects down to 24-25 R mag. All the VLA images and all the deep CCD images of the RC SS fields, collected up to now, are given. An updated list of calibrators with the known redshifts of the same SS FRII class RGs was compiled to estimate photometric redshifts, redshifts from angular size - redshift relations and by the radio "standard candle" method. The mean redshift of the RC SS FRII RG list happened to be greater than 2. BVRI photometry was made, and by standard model fittings we estimated "color" redshifts and the ages of stellar systems of the parent gE galaxies in 14 cases. Several objects were found in which active star formation began in the first billion years after the Big Bang. We believe that more than 10000 of such old active galaxies are available on the sky and all of them are in the range of present day optical and radio facilities.
- ID:
- ivo://CDS.VizieR/J/A+A/459/679
- Title:
- RB photometry of LSBG in Coma
- Short Name:
- J/A+A/459/679
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on a search for faint (R total magnitude fainter than 21) and low surface brightness galaxies (R central surface brightness fainter than ~24) (fLSBs) in a 0.72x0.82deg^2^ area centered on the Coma cluster. We analyzed deep B and R band CCD imaging obtained using the CFH12K camera at CFHT and found 735 fLSBs. The total B magnitudes, at the Coma cluster redshift, range from -13 to -9 with B central surface brightness as faint as 27mag/arcsec^2^.
2986. RC2 Catalogue
- ID:
- ivo://CDS.VizieR/VII/112
- Title:
- RC2 Catalogue
- Short Name:
- VII/112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This standardized documentation file does not contain a complete description of the electronic version of the RC2 catalogue; please refer to the "doc.tex" file prepared by Theresa A. Nagy and Robert S. Hill.
- ID:
- ivo://CDS.VizieR/J/AJ/108/2128
- Title:
- RC3 corrections and additions
- Short Name:
- J/AJ/108/2128
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Lists of corrections and additions to the Third Reference Catalogue of Bright Galaxies (RC3, Cat. <VII/155>) are given. The corrected version of the catalogue (RC3.9b), dated April 1994, is currently available through the national data centers.
- ID:
- ivo://CDS.VizieR/J/AJ/125/2307
- Title:
- Rc photometry of ENEAR survey galaxies
- Short Name:
- J/AJ/125/2307
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present R-band CCD photometry for 1332 early-type galaxies, observed as part of the Early-type NEARby galaxies (ENEAR) survey of peculiar motions using early-type galaxies in the nearby universe. Circular apertures are used to trace the surface brightness profiles, which are then fitted by a two-component bulge-disk model. From the fits, we obtain the structural parameters required to estimate galaxy distances using the Dn-{sigma} and fundamental plane relations. The photometric data reported here represent one of the largest high-quality and uniform all-sky samples currently available for early-type galaxies in the nearby universe, especially suitable for peculiar motion studies.
- ID:
- ivo://CDS.VizieR/J/AJ/135/1488
- Title:
- Rc photometry of galaxies in NGC 5353/4 group
- Short Name:
- J/AJ/135/1488
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This third paper in a series about the dwarf galaxy populations in groups within the Local Supercluster concerns the intermediate mass (2.1x10^13^M_{sun}_) NGC 5353/4 Group with a core dominated by S0 systems and a periphery of mostly spiral systems. Dwarf galaxies are strongly concentrated toward the core. The mass-to-light ratio M/L_R_=105M_{sun}_/L_{sun}_ is a factor of 3 lower than for the two groups studied earlier in the series. The properties of the group suggest it is much less dynamically evolved than those two groups of early-type galaxies. By comparison, the NGC 5353/4 Group lacks superluminous systems but has a large fraction of intermediate-luminosity galaxies; or equivalently, a luminosity function with a flatter faint-end slope. The luminosity function for the NGC 5353/4 Group should steepen as the intermediate-luminosity galaxies merge. Evidence for the ongoing collapse of the group is provided by the unusually large incidence of star-formation activity in small galaxies with early morphological types. The pattern in the distribution of galaxies with activity suggests a succession of infall events. Residual gas in dwarfs that enter the group is used up in sputtering events. The resolution of midlife crises is exhaustion.
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/533
- Title:
- Recently quenched elliptical galaxies in SDSS
- Short Name:
- J/MNRAS/442/533
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Sloan Digital Sky Survey to investigate the properties of massive elliptical galaxies in the local Universe (z<=0.08) that have unusually blue optical colours. Through careful inspection, we distinguish elliptical from non-elliptical morphologies among a large sample of similarly blue galaxies with high central light concentrations (c_r_>=2.6). These blue ellipticals comprise 3.7 per cent of all c_r>=2.6 galaxies with stellar masses between 10^10^ and 10^11^h^-2^M_{sun}_. Using published fibre spectrum diagnostics, we identify a unique subset of 172 non-star-forming ellipticals with distinctly blue urz colours and young (<3Gyr) light-weighted stellar ages. These recently quenched ellipticals (RQEs) have a number density of 2.7-4.7x10^-5^h^3^/Mpc^3^ and sufficient numbers above 2.5x10^10^h^-2^M_{sun}_ to account for more than half of the expected quiescent growth at late cosmic time assuming that this phase lasts 0.5Gyr. RQEs have properties that are consistent with a recent merger origin (i.e. they are strong 'first-generation' elliptical candidates), yet few involved a starburst strong enough to produce an E+A signature. The preferred environment of RQEs (90 per cent reside at the centres of <3x10^12^h^-1^M_{sun}_ groups) agrees well with the 'small group scale' predicted for maximally efficient spiral merging on to their halo centre and rules out satellite-specific quenching processes. The high incidence of Seyfert and LINER activity in RQEs and their plausible descendants may heat the atmospheres of small host haloes sufficiently to maintain quenching.
