- 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.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/338/525
- Title:
- Recent star formation in UCM galaxies
- Short Name:
- J/MNRAS/338/525
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the integrated properties of the stellar populations in the Universidad Complutense de Madrid (UCM) Survey galaxies. Applying the techniques described in the first paper of this series (Perez-Gonzalez et al., 2003, Cat. <J/MNRAS/338/508>), we derive ages, burst masses and metallicities of the newly formed stars in our sample galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/381/1369
- Title:
- Redshifts in Subaru/XMM Deep Field
- Short Name:
- J/MNRAS/381/1369
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present multiobject spectroscopy of galaxies in the immediate (Mpc-scale) environments of four low-power (L_1.4GHz_~<10^25^W/Hz) radio galaxies at z~0.5, selected from the Subaru/XMM-Newton Deep Field. We use the spectra to calculate velocity dispersions and central redshifts of the groups the radio galaxies inhabit, and combined with XMM-Newton (0.3-10keV) X-ray observations investigate the L_X_-{sigma}_v_ and T_X_-{sigma}_v_ scaling relationships. All the radio galaxies reside in moderately rich groups - intermediate environments between poor groups and rich clusters, with remarkably similar X-ray properties.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJS/150/181
- Title:
- Redshifts of 110 radio-loud AGNs
- Short Name:
- J/ApJS/150/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report accurate redshifts of 110 active galaxies (mostly radio-loud objects at z<0.4) observed in the course of a survey to find broad, double-peaked emission lines. These redshifts are measured from the narrow emission lines of these objects and are accurate to at least one part in 10^4^. For each object we determine a redshift from high- and low-ionization lines separately, as well as an average redshift from all the available lines. We find that in about 15% of cases, the low-ionization lines yield a slightly higher redshift than the high-ionization lines; the average redshift difference amounts to a velocity difference of approximately 80km/s. In addition to the redshift measurements we also report revised redshifts for two objects as well as new classifications for three narrow-line objects.
- ID:
- ivo://CDS.VizieR/J/ApJ/622/772
- Title:
- Redshift survey of submillimeter galaxies
- Short Name:
- J/ApJ/622/772
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained spectroscopic redshifts using the Keck I telescope for a sample of 76 submillimeter galaxies (SMGs), with a median 850{mu}m flux density of 5.7mJy, for which precise positions are available through their faint radio emission.
- ID:
- ivo://CDS.VizieR/J/ApJ/525/127
- Title:
- RGB sample of BL Lacertae objects
- Short Name:
- J/ApJ/525/127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Combining newly identified and previously known BL Lacertae objects from the ROSAT All-Sky Survey-Green Bank (RGB) catalog, we present a sample of 127 BL Lacertae objects, the largest ever derived from a single uniform survey. A complete sample of 33 objects brighter than O=18.0 mag is also presented. These samples are compared to other known BL Lac samples and are generally found to exhibit properties intermediate between those of the previously disparate classes of high- and low-energy-peaked BL Lacertae objects (HBLs and LBLs, respectively). This result is most dramatic in the distribution of the X-ray to radio logarithmic flux ratios, where the RGB BL Lacertae objects are shown to peak precisely where the sharp dichotomy between the two subclasses was previously seen.
- ID:
- ivo://CDS.VizieR/J/AJ/157/126
- Title:
- RGZ: distortion of radio galaxies by galaxy clusters
- Short Name:
- J/AJ/157/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the impact of cluster environment on the morphology of a sample of 4304 extended radio galaxies from Radio Galaxy Zoo. A total of 87% of the sample lies within a projected 15 Mpc of an optically identified cluster. Brightest cluster galaxies (BCGs) are more likely than other cluster members to be radio sources, and are also moderately bent. The surface density as a function of separation from cluster center of non-BCG radio galaxies follows a power law with index -1.10+/-0.03 out to 10 r_500_ (~7 Mpc), which is steeper than the corresponding distribution for optically selected galaxies. Non-BCG radio galaxies are statistically more bent the closer they are to the cluster center. Within the inner 1.5 r_500_ (~1 Mpc) of a cluster, non-BCG radio galaxies are statistically more bent in high-mass clusters than in low-mass clusters. Together, we find that non-BCG sources are statistically more bent in environments that exert greater ram pressure. We use the orientation of bent radio galaxies as an indicator of galaxy orbits and find that they are preferentially in radial orbits. Away from clusters, there is a large population of bent radio galaxies, limiting their use as cluster locators; however, they are still located within statistically overdense regions. We investigate the asymmetry in the tail length of sources that have their tails aligned along the radius vector from the cluster center, and find that the length of the inward-pointing tail is weakly suppressed for sources close to the center of the cluster.
- ID:
- ivo://CDS.VizieR/J/MNRAS/355/1303
- Title:
- Rmag surface brightness of HIDEEP galaxies
- Short Name:
- J/MNRAS/355/1303
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Minchin et al. (2004, Cat. <J/MNRAS/346/787>) have recently placed limits on the cosmological significance of gas-rich low surface brightness (LSB) galaxies as a proportion of the total population of gas-rich galaxies by carrying out a very deep survey (HIDEEP) for neutral hydrogen (HI) with the Parkes multibeam system. Such a survey avoids the surface brightness selection effects that limit the usefulness of optical surveys for finding LSB galaxies. To complement the HIDEEP survey, we have digitally stacked eight 1-h R-band Tech Pan films from the UK Schmidt Telescope covering 36{deg}^2^ of the survey area to reach a very deep isophotal limit of 26.5Rmag/arcsec^2^. At this level, we find that all of the 129 HI sources within this area have optical counterparts and that 107 of them can be identified with individual galaxies.
- 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.
