- ID:
- ivo://CDS.VizieR/J/MNRAS/394/2197
- Title:
- Distant radio galaxies in southern hemisphere
- Short Name:
- J/MNRAS/394/2197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a sample of 234 ultra-steep-spectrum (USS) selected radio sources in order to find high-redshift radio galaxies. The sample covers the declination range -40{deg}<{delta}<-30{deg} in the overlap region between the 1400-MHz National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) Sky Survey (NVSS), 408-MHz Revised Molonglo Reference Catalogue and the 843-MHz Sydney University Molonglo Sky Survey (the MRCR-SUMSS sample). This is the second in a series of papers on the MRCR-SUMSS sample, and here we present the K-band (2.2{mu}m) imaging of 173 of the sources primarily from the Magellan and the Anglo-Australian Telescopes. We detect a counterpart to the radio source in 93 per cent of the new K-band images which, along with previously published data, makes this the largest published sample of K-band counterparts to USS-selected radio galaxies. The location of the K-band identification has been compared to the features of the radio emission for the double sources. We find that the identification is most likely to lie near the mid-point of the radio lobes rather than closer to the brighter lobe, making the centroid a less likely place to find the optical counterpart. 79 per cent of the identifications are less than 1arcsec from the radio lobe axis. These results differ from studies of low-redshift radio samples where the environments are typically not nearly so dense and disturbed as those at high redshift. In contrast to some literature samples, we find that the majority of our sample shows no alignment between the near-infrared and radio axes. Several different morphologies of aligned structures are found and those that are aligned within 10{deg} are consistent with jet-induced star formation. The distribution and median value of the K-band magnitudes for the MRCR-SUMSS sample are found to be similar to several other USS-selected samples even though each sample has a very different median 1400MHz flux density. USS selection from a lower radio-frequency sample has not netted fainter K-band magnitudes, which may imply that the k-correction is not responsible for the effectiveness of USS selection.
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Search Results
- ID:
- ivo://CDS.VizieR/II/234
- Title:
- Draft EIS Colour Catalog
- Short Name:
- II/234
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is a DRAFT multicolour catalogue resulting from the multi- passband ESO Imaging Survey (EIS, see J/A+A/379/740) in the direction of the Chandra Deep Field South (CDF-S), located at RA=03h32m, Dec=-27{deg}48'. The observations were conducted at the ESO/MPG 2.2 m telescope at La Silla using the 8kx8k Wide-Field Imager (WFI).
- ID:
- ivo://CDS.VizieR/J/A+A/555/A11
- Title:
- DUNES survey observational results
- Short Name:
- J/A+A/555/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their solar system's counterparts are the asteroid and Edgeworth-Kuiper belts. The Herschel Open Time Key Programme DUNES (DUst around NEarby Stars) survey aims at detecting extra-solar analogues to the Edgeworth-Kuiper belt around solar-type stars, putting in this way the solar system into context. We used Herschel/PACS to observe a sample of nearby FGK stars. Data at 100 and 160 micron were obtained, complemented in some cases with observations at 70 micron, and at 250, 350 and 500 micron using SPIRE. The paper provides a detailed description of the observational results of the survey.
- ID:
- ivo://CDS.VizieR/J/ApJ/769/116
- Title:
- Dust-obscured galaxies in the local universe
- Short Name:
- J/ApJ/769/116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use Wide-field Infrared Survey Explorer (WISE), AKARI, and Galaxy Evolution Explorer (GALEX) data to select local analogs of high-redshift (z~2) dust obscured galaxies (DOGs). We identify 47 local DOGs with S_12{mu}m_/S_0.22{mu}m_>=892 and S_12{mu}m_>20mJy at 0.05<z<0.08 in the Sloan Digital Sky Survey data release 7. The infrared (IR) luminosities of these DOGs are in the range 3.4x10^10^(L_{sun}_)<~L_IR_<~7.0x10^11^(L_{sun}_) with a median L_IR_ of 2.1x10^11^(L_{sun}_). We compare the physical properties of local DOGs with a control sample of galaxies that have lower S_12{mu}m_/S_0.22{mu}m_ but have similar redshift, IR luminosity, and stellar mass distributions. Both WISE 12{mu}m and GALEX near-ultraviolet (NUV) flux densities of DOGs differ from the control sample of galaxies, but the difference is much larger in the NUV. Among the 47 DOGs, 36%+/-7% have small axis ratios in the optical (i.e., b/a<0.6), larger than the fraction among the control sample (17%+/-3%). There is no obvious sign of interaction for many local DOGs. No local DOGs have companions with comparable optical magnitudes closer than ~50kpc. The large- and small-scale environments of DOGs are similar to the control sample. Many physical properties of local DOGs are similar to those of high-z DOGs, even though the IR luminosities of local objects are an order of magnitude lower than for the high-z objects: the presence of two classes (active galactic nuclei- and star formation-dominated) of DOGs, abnormal faintness in the UV rather than extreme brightness in the mid-IR, and diverse optical morphology. These results suggest a common underlying physical origin of local and high-z DOGs. Both seem to represent the high-end tail of the dust obscuration distribution resulting from various physical mechanisms rather than a unique phase of galaxy evolution.
- ID:
- ivo://CDS.VizieR/J/ApJ/813/L15
- Title:
- Dwarf galaxies in Fornax cluster from NGFS
- Short Name:
- J/ApJ/813/L15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of 158 previously undetected dwarf galaxies in the Fornax cluster central regions using a deep coadded u-, g-, and i-band image obtained with the Dark Energy Camera wide-field camera mounted on the 4-m Blanco telescope at the Cerro Tololo Interamerican Observatory as part of the Next Generation Fornax Survey (NGFS). The new dwarf galaxies have quasi-exponential light profiles, effective radii 0.1<r_e_<2.8kpc, and average effective surface brightness values 22.0<{mu}_i_<28.0mag/arcsec2. We confirm the existence of ultra-diffuse galaxies (UDGs) in the Fornax core regions that resemble counterparts recently discovered in the Virgo and Coma galaxy clusters. We also find extremely low surface brightness NGFS dwarfs, which are several magnitudes fainter than the classical UDGs. The faintest dwarf candidate in our NGFS sample has an absolute magnitude of M_i_=-8.0mag. The nucleation fraction of the NGFS dwarf galaxy sample appears to decrease as a function of their total luminosity, reaching from a nucleation fraction of >75% at luminosities brighter than M_i_~=-15.0mag to 0% at luminosities fainter than M_i_~=-10.0mag. The two-point correlation function analysis of the NGFS dwarf sample shows an excess on length scales below ~100 kpc, pointing to the clustering of dwarf galaxies in the Fornax cluster core.
- ID:
- ivo://CDS.VizieR/J/AJ/133/715
- Title:
- Dwarf galaxies of the Local Group
- Short Name:
- J/AJ/133/715
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar Observatory Sky Survey and ESO/Science Research Council survey plates, and follow-up observations were performed to determine whether they were indeed overlooked members of the Local Group. Only two galaxies (Antlia and Cetus) were discovered this way out of 206 candidates. Based on internal and external comparisons, we estimate that our visual survey is more than 77% complete for objects larger than 1' in size and with a surface brightness greater than an extremely faint limit over the 72% of the sky not obstructed by the Milky Way.
- ID:
- ivo://CDS.VizieR/J/other/RAA/15.1414
- Title:
- E+A galaxy candidates in LAMOST DR2
- Short Name:
- J/other/RAA/15.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 70 E+A galaxies is selected from 37206 galaxies in the second data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). This sample is selected according to the criteria for E+A galaxies defined by Goto, and each of these objects is further visually identified. In this sample, most objects are low redshift E+A galaxies with z<0.25, and are located in an area of the sky with high Galactic latitude and magnitude from 14 to 18mag in the g, r and i bands. A stellar population analysis of the whole sample indicates that the E+A galaxies are characterized by both young and old stellar populations (SPs), and the metal-rich SPs have relatively higher contributions than the metal-poor ones. Additionally, a morphological classification of these objects is performed based on images taken from the Sloan Digital Sky Survey.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/1879
- Title:
- EC Blue Object survey. -40{deg}>b>-50{deg}
- Short Name:
- J/MNRAS/453/1879
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results for Zone 3 of the Edinburgh-Cape (EC) Blue Object survey are presented. This zone covers that part of the South Galactic Cap between 40{deg} and 50{deg} from the Galactic plane and south of about -12.3{deg} of declination. EC Zone 3 contains 53 UK Schmidt Telescope fields covering about 1400 deg2 in which we find some 534 blue objects, including hot subdwarfs (~39 percent), white dwarfs (~21 percent), cataclysmic variables (~2 percent) and some star-like galaxies (~9 percent). A further 178 cooler stars observed in the survey, including low-metallicity F- and G-type stars, are also listed. Both low-dispersion spectroscopic classification and UBV photometry are presented for almost all of the hot objects and either spectroscopy or photometry (sometimes both) for the cooler ones.
- ID:
- ivo://CDS.VizieR/J/ApJ/796/60
- Title:
- ECDFS galaxies photometric redshifts & counterparts
- Short Name:
- J/ApJ/796/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present photometric redshifts and associated probability distributions for all detected sources in the Extended Chandra Deep Field South (ECDFS). This work makes use of the most up-to-date data from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS) and the Taiwan ECDFS Near-Infrared Survey (TENIS) in addition to other data. We also revisit multi-wavelength counterparts for published X-ray sources from the 4Ms CDFS and 250ks ECDFS surveys, finding reliable counterparts for 1207 out of 1259 sources (~96%). Data used for photometric redshifts include intermediate-band photometry deblended using the TFIT method, which is used for the first time in this work. Photometric redshifts for X-ray source counterparts are based on a new library of active galactic nuclei/galaxy hybrid templates appropriate for the faint X-ray population in the CDFS. Photometric redshift accuracy for normal galaxies is 0.010 and for X-ray sources is 0.014 and outlier fractions are 4% and 5.2%, respectively. The results within the CANDELS coverage area are even better, as demonstrated both by spectroscopic comparison and by galaxy-pair statistics. Intermediate-band photometry, even if shallow, is valuable when combined with deep broadband photometry. For best accuracy, templates must include emission lines.
- ID:
- ivo://CDS.VizieR/J/ApJ/642/L13
- Title:
- ECDFS MUSYC galaxies UBVRIzNB5000 photometry
- Short Name:
- J/ApJ/642/L13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We selected 40 candidate Ly{alpha}-emitting galaxies (LAEs) at z~3.1 with observed-frame equivalent widths greater than 150{AA} and inferred emission-line fluxes above 2.5x10^-17^ergs/cm^2^/s from deep narrowband and broadband MUSYC images of the Extended Chandra Deep Field South. Covering 992-arcmin^2^, this is the largest "blank field" surveyed for LAEs at z~3, allowing an improved estimate of the space density of this population of (3+/-1)x10^4^h/Mpc^3^. Spectroscopic follow-up of 23 candidates yielded 18 redshifts, all at z~3.1. Over 80% of the LAEs are dimmer in continuum magnitude than the typical Lyman break galaxy (LBG) spectroscopic limit of R=25.5 (AB), with a median continuum magnitude R~27 and very blue continuum colors, V-z~=0.