- ID:
- ivo://CDS.VizieR/J/ApJ/698/1095
- Title:
- The FIRST-2MASS red QSO survey. II.
- Short Name:
- J/ApJ/698/1095
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results on a survey to find extremely dust-reddened Type 1 quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a candidate list of 122 potential red quasars. With more than 80% spectroscopically identified objects, well over 50% are classified as dust-reddened Type 1 quasars, whose reddenings (E(B-V)) range from approximately 0.1 to 1.5mag. They lie well off the color selection windows usually used to detect quasars and many fall within the stellar locus, which would have made it impossible to find these objects with traditional color selection techniques. The reddenings found are much more consistent with obscuration happening in the host galaxy rather than stemming from the dust torus. We find an unusually high fraction of broad absorption line (BAL) quasars at high redshift, all but one of them belonging to the low-ionization BAL (LoBAL) class and many also showing absorption in the metastable FeII line (FeLoBAL). The discovery of further examples of dust-reddened LoBAL quasars provides more support for the hypothesis that BAL quasars (at least LoBAL quasars) represent an early stage in the lifetime of the quasar. The fact that we see such a high fraction of BALs could indicate that the quasar is in a young phase in which quasar feedback from the BAL winds is suppressing star formation in the host galaxy.
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- ID:
- ivo://CDS.VizieR/J/ApJS/252/15
- Title:
- The GNRIS-Distant Quasar Survey (GNRIS-DQS)
- Short Name:
- J/ApJS/252/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic measurements for 226 sources from the Gemini Near Infrared Spectrograph-Distant Quasar Survey (GNIRS-DQS). Being the largest uniform, homogeneous survey of its kind, it represents a flux-limited sample (m_i_<~19.0mag, H<~16.5mag) of Sloan Digital Sky Survey (SDSS) quasars at 1.5<~z<~3.5 with a monochromatic luminosity ({lambda}L_{lambda}_) at 5100{AA} in the range of 10^44^-10^46^erg/s. A combination of the GNIRS and SDSS spectra covers principal quasar diagnostic features, chiefly the CIV{lambda}1549, MgII{lambda}{lambda}2798,2803, H{beta}{lambda}4861, and [OIII]{lambda}{lambda}4959,5007 emission lines, in each source. The spectral inventory will be utilized primarily to develop prescriptions for obtaining more accurate and precise redshifts, black hole masses, and accretion rates for all quasars. Additionally, the measurements will facilitate an understanding of the dependence of rest-frame ultraviolet-optical spectral properties of quasars on redshift, luminosity, and Eddington ratio, and test whether the physical properties of the quasar central engine evolve over cosmic time.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/32
- Title:
- The HII Region Discovery Survey (HRDS). II.
- Short Name:
- J/ApJS/194/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank Telescope (GBT) HII Region Discovery Survey has doubled the number of known HII regions in the Galactic zone 343{deg}<=l<=67{deg} with |b|<=1{deg}. We detected 603 discrete hydrogen radio recombination line (RRL) components at 9GHz (3cm) from 448 targets. Our targets were selected based on spatially coincident mid-infrared and 20cm radio continuum emission. Such sources are almost invariably HII regions; we detected hydrogen RRL emission from 95% of our target sample. The sensitivity of the GBT and the power of its spectrometer together made this survey possible. Here, we provide a catalog of the measured properties of the RRL and continuum emission from the survey nebulae. The derived survey completeness limit, 180mJy at 9GHz, is sufficient to detect all HII regions ionized by single O-stars to a distance of 12kpc. We discovered 34 first quadrant negative-velocity HII regions, which lie at extreme distances from the Sun and appear to be part of the Outer Arm. We found RRL emission from 208 Spitzer GLIMPSE 8.0um "bubble" sources, 65 of which have been cataloged previously. It thus appears that nearly all GLIMPSE bubbles are HII regions and that ~50% of all Galactic HII regions have a bubble morphology at 8.0um.
- ID:
- ivo://CDS.VizieR/J/ApJ/746/85
- Title:
- THe HST Cluster Supernova Survey. V.
- Short Name:
- J/ApJ/746/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe Ia were discovered over the redshift interval 0.623<z<1.415. Of these SNe Ia, 14 pass our strict selection cuts and are used in combination with the world's sample of SNe Ia to derive the best current constraints on dark energy. Of our new SNe Ia, 10 are beyond redshift z = 1, thereby nearly doubling the statistical weight of HST-discovered SNe Ia beyond this redshift. Our detailed analysis corrects for the recently identified correlation between SN Ia luminosity and host galaxy mass and corrects the NICMOS zero point at the count rates appropriate for very distant SNe Ia. Adding these SNe improves the best combined constraint on dark-energy density, {rho}_DE_(z), at redshifts 1.0<z<1.6 by 18% (including systematic errors).
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/196
- Title:
- The invisible AGN catalogue
- Short Name:
- J/MNRAS/468/196
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A large fraction of active galactic nuclei (AGN) are 'invisible' in extant optical surveys due to either distance or dust-obscuration. The existence of this large population of dust-obscured, infrared (IR)-bright AGN is predicted by models of galaxy-supermassive black hole coevolution and is required to explain the observed X-ray and IR backgrounds. Recently, IR colour cuts with Wide-field Infrared Survey Explorer have identified a portion of this missing population. However, as the host galaxy brightness relative to that of the AGN increases, it becomes increasingly difficult to differentiate between IR emission originating from the AGN and from its host galaxy. As a solution, we have developed a new method to select obscured AGN using their 20-cm continuum emission to identify the objects as AGN. We created the resulting invisible AGN catalogue by selecting objects that are detected in AllWISE (mid-IR) and FIRST (20 cm), but are not detected in SDSS (optical) or 2MASS (near-IR), producing a final catalogue of 46 258 objects. 30 per cent of the objects are selected by existing selection methods, while the remaining 70 per cent represent a potential previously unidentified population of candidate AGN that are missed by mid-IR colour cuts. Additionally, by relying on a radio continuum detection, this technique is efficient at detecting radio-loud AGN at z>=0.29, regardless of their level of dust obscuration or their host galaxy's relative brightness.
- ID:
- ivo://CDS.VizieR/J/A+A/400/903
- Title:
- The ISOGAL field FC-01863+00035
- Short Name:
- J/A+A/400/903
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A 0.35x0.29{deg} field centered at l=-18.63{deg}, b=0.35{deg} was observed during the ISOGAL survey by ISOCAM imaging at 7{mu}m and 15{mu}m. 648 objects were detected and their brightness are measured. By combining with the DENIS data in the near-infrared J and Ks bands, one derives the extinction at 7{mu}m through A_Ks_-A_7_=0.35(A_J_-A_Ks_) which yields A_7_/Av~0.03 from the near-IR extinction values of van de Hulst-Glass (Glass, 1999MNRAS.308..127G). The extinction structure along the line of sight is then determined from the values of J-Ks or Ks-[7] of the ISOGAL sources identified as RGB or early AGB stars with mild mass-loss. The distribution of Av ranges from 0 to ~45 and it reflects the concentration of the extinction in the spiral arms. Based on their locations in color-magnitude diagrams and a few cross-identifications with IRAS and MSX sources, the nature of objects is discussed in comparison with the case of a low extinction field in Baade's Window. Most of the objects are either AGB stars with moderate mass loss rate or luminous RGB stars. Some of them may be AGB stars with high mass loss rate. In addition, a few young stellar objects (YSOs) are present.
- ID:
- ivo://CDS.VizieR/II/243
- Title:
- The ISOGAL Point Source Catalogue - IGPSC
- Short Name:
- II/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ISOGAL survey is one of the largest imaging programme performed by the ISO satellite. About 16deg^2^ mainly distributed in the inner Galactic disk were mapped at 7 and/or 15 micron ({mu}m). Because of highly structured background and high source density, a special point source extraction algorithm was used and resulted in a 100000 point source catalogue. The mid-infrared data have been associated with near-infrared DENIS sources, providing an up to five wavelength photometric catalogue with a typical astrometric accuracy better than 1 arcsecond. The point source catalogue contains the positional and photometric parameters of all ISOGAL sources, together with various quality flags aimed at giving an estimate of the reliability of the detections and of the associations between the different bands (see the paper for a complete description).
- ID:
- ivo://CDS.VizieR/J/A+A/390/1033
- Title:
- The ISO-SWS post-helium atlas
- Short Name:
- J/A+A/390/1033
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of near-infrared spectra (2.36{mu}m-4.1{mu}m) of ~300 stars at moderate resolution ({lambda}/{delta}{lambda}~1500-2000). The spectra were recorded using the Short-Wavelength Spectrometer aboard the Infrared Space Observatory (ISO-SWS). The bulk of the observations were performed during a dedicated observation campaign after the liquid helium depletion of the ISO satellite, the so-called post-helium programme. This programme was aimed at extending the MK-classification to the near-infrared.
- ID:
- ivo://CDS.VizieR/VII/233
- Title:
- The 2MASS Extended sources
- Short Name:
- VII/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Between 1997 June and 2001 February the Two Micron All Sky Survey (2MASS) collected 25.4 Tbytes of raw imaging data covering 99.998% of the celestial sphere in the near-infrared J(1.25{mu}m), H(1.65{mu}m), and Ks(2.16{mu}m) bandpasses. Observations were conducted from two dedicated 1.3 m diameter telescopes located at Mount Hopkins, Arizona, and Cerro Tololo, Chile. The 2MASS All-Sky Data Release includes the FITS images covering the entire sky, a Point Source Catalog (PSC) of 471 million sources (Cat. II/242), and the present Extended Source Catalog. The 2MASS Extended Source Catalog contains sources that are extended with respect to the instantaneous PSF, such as galaxies and Galactic nebulae. The algorithms used to create the 2MASX catalog are described by Jarett et al. (2000AJ....119.2498J), and in the 2MASS Explanatory Supplement (accessible from the 2MASS Home Page). Briefly, point/ extended-source discrimination was conducted for each band-merged point-source detection by comparing a variety of radial shape, surface brightness, image moments, and symmetry parameters with characteristic stellar parameters using an oblique decision tree classifier. The classification tests included filters to exclude double and triple stars, which were one of the main contaminants in high source density regions. Stellar parameters were measured empirically as a function of time in each scan to compensate for variations in the atmospheric seeing using the aggregate properties of band-merged point-source extractions. The catalog contains 389 columns described briefly in the "Byte-by-byte Description" section below; their description includes also the 2MASS database original column names used in the original descriptions.
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/2840
- Title:
- The 2M++ galaxy redshift catalogue
- Short Name:
- J/MNRAS/416/2840
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Peculiar velocities arise from gravitational instability, and thus are linked to the surrounding distribution of matter. In order to understand the motion of the Local Group with respect to the cosmic microwave background, a deep all-sky map of the galaxy distribution is required. Here we present a new redshift compilation of 69160 galaxies, dubbed 2M++, to map large-scale structures of the local Universe over nearly the whole sky, and reaching depths of K<=12.5, or 200h^-1^Mpc. The target catalogue is based on the Two-Micron All-Sky Survey Extended Source Catalog (2MASS-XSC). The primary sources of redshifts are the 2MASS Redshift Survey, the 6dF galaxy redshift survey and the Sloan Digital Sky Survey (Data Release 7). We assess redshift completeness in each region and compute the weights required to correct for redshift incompleteness and apparent magnitude limits, and discuss corrections for incompleteness in the zone of avoidance. We present the density field for this survey, and discuss the importance of large-scale structures such as the Shapley Concentration.
