- ID:
- ivo://CDS.VizieR/J/MNRAS/328/805
- Title:
- The 2dF QSO Redshift Survey. VIII
- Short Name:
- J/MNRAS/328/805
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the highest signal-to-noise ratio spectra from the 2dF QSO Redshift Survey (2QZ) 10k release (Cat. <VII/223>) and identify over 100 new low-ionization heavy-element absorbers: damped Lyman-{alpha} (DLA) candidates suitable for higher-resolution follow-up observations. These absorption systems map the spatial distribution of high-z metals in exactly the same volumes as the foreground 2QZ QSOs themselves sample and hence the 2QZ gives us the unique opportunity to compare directly the two tracers of large-scale structure. We examine the cross-correlation of the two populations to see how they are relatively clustered, and, by considering the colour of the QSOs, detect a small amount of dust in these metal systems.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/VII/223
- Title:
- The 2dF QSO Redshift Survey. V. The 10k catalogue
- Short Name:
- VII/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2dF QSO Redshift Survey (2QZ) 10k catalogue is the first release of the 2QZ, containing over 10000 QSOs. There are a total of 20590 sources listed, for which spectra have been obtained using the 2-degree field facility at the Anglo-Australian Observatory. Current data covers an effective area of 289.6deg^2^ for QSO candidates with magnitudes 18.25<b_J_<20.85. The file 2qz_10k.dat contains the names, positions, magnitudes, spectroscopic identifications and redshifts for each of the sources.
21633. The 2dF-SDSS QSO survey
- ID:
- ivo://CDS.VizieR/J/MNRAS/392/19
- Title:
- The 2dF-SDSS QSO survey
- Short Name:
- J/MNRAS/392/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final spectroscopic QSO catalogue from the 2dF-SDSS LRG (luminous red galaxy) and QSO (2SLAQ) survey. This is a deep, 18<g<21.85 (extinction corrected), sample aimed at probing in detail the faint end of the broad line active galactic nuclei luminosity distribution at z<=2.6. The candidate QSOs were selected from SDSS photometry and observed spectroscopically with the 2dF spectrograph on the Anglo-Australian Telescope. This sample covers an area of 191.9 deg2 and contains new spectra of 16326 objects, of which 8764 are QSOs and 7623 are newly discovered [the remainder were previously identified by the 2dF QSO Redshift Survey (2QZ) and SDSS]. The full QSO sample (including objects previously observed in the SDSS and 2QZ surveys) contains 12702 QSOs. The new 2SLAQ spectroscopic data set also contains 2343 Galactic stars, including 362 white dwarfs, and 2924 narrow emission-line galaxies with a median redshift of z=0.22.
21634. The Disc of the Milky Way
- ID:
- ivo://edu.gavo.org/eurovo/cosadie_milkyway
- Title:
- The Disc of the Milky Way
- Date:
- 02 Apr 2025 14:48:21
- Publisher:
- The GAVO DC team
- Description:
- Within this use case you discover the shape and thickness of the disc of our own Galaxy by counting stars within and around the Milky Way. With the use of both Aladin and Stellarium you draw the line corresponding to the disc of the Milky Way in a coordinate diagram.
21635. The DiskMass survey. I.
- ID:
- ivo://CDS.VizieR/J/ApJ/716/198
- Title:
- The DiskMass survey. I.
- Short Name:
- J/ApJ/716/198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a survey of the mass surface density of spiral disks, motivated by outstanding uncertainties in rotation-curve decompositions. Our method exploits integral-field spectroscopy to measure stellar and gas kinematics in nearly face-on galaxies sampled at 515, 660, and 860nm, using the custom-built SparsePak and PPak instruments. A two-tiered sample, selected from the UGC, includes 146 nearly face-on galaxies, with B<14.7 and disk scale lengths between 10 and 20 arcsec, for which we have obtained H{alpha} velocity fields; and a representative 46 galaxy subset for which we have obtained stellar velocities and velocity dispersions. The survey is augmented by 4-70um Spitzer IRAC and MIPS photometry, ground-based UBVRIJHK photometry, and HI aperture-synthesis imaging. We outline the spectroscopic analysis protocol for deriving precise and accurate line-of-sight stellar velocity dispersions. Our key measurement is the dynamical disk-mass surface density. Star formation rates and kinematic and photometric regularity of galaxy disks are also central products of the study.
- ID:
- ivo://CDS.VizieR/J/A+A/363/L1
- Title:
- The distance modulus of the LMC
- Short Name:
- J/A+A/363/L1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing photometric data, linear pulsation and stellar atmosphere models. If we set E_(B-V)_=0.11 and [M/H]=-1.5 for LMC, we get M-m=18.52mag. The fact that the distance moduli obtained in this and in our former studies of cluster RRd and Small Magellanic Cloud beat Cepheids agree so well, implies that the only serious source of error is the zero point of the temperature scale, which should not have larger than +/-0.10mag effect on the distance modulus.
- ID:
- ivo://CDS.VizieR/J/A+A/557/A44
- Title:
- The doubly lensed quasar SDSS J1001+5027
- Short Name:
- J/A+A/557/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents optical R-band light curves and the time delay of the doubly imaged gravitationally lensed quasar SDSS J1001+5027 at a redshift of 1.838. We have observed this target for more than six years, between March 2005 and July 2011, using the 1.2-m Mercator Telescope, the 1.5-m telescope of the Maidanak Observatory and the 2-m Himalayan Chandra Telescope. Our resulting light curves are composed of 443 independent epochs, and show strong intrinsic quasar variability, with an amplitude of the order of 0.2 magnitudes. From this data, we measure the time delay using five different methods, all relying on distinct approaches. One of these techniques is a new development presented in this paper. All our time-delay measurements are perfectly compatible. By combining them, we conclude that image A is leading B by 119.3+/-3.3 days (1{sigma}, 2.8%), including systematic errors. It has been shown recently that such accurate time-delay measurements offer a highly complementary probe of dark energy and spatial curvature, as they independently constrain the Hubble constant. The next mandatory step towards using SDSS J1001+5027 in this context will be the measurement of the redshift of the lensing galaxy, in combination with deep HST imaging.
21638. The DRAO polarization survey
- ID:
- ivo://CDS.VizieR/J/A+A/448/411
- Title:
- The DRAO polarization survey
- Short Name:
- J/A+A/448/411
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The fits files contain the observed and interpolated data of a survey of linear polarization (Stokes U and Q) at 1.4GHz, obtained with the 25.6-m telescope of the Dominion Radio Astrophysical Observatory in Canada. The angular resolution is 36 arcmin. The data are corrected for ground radiation and tied to absolute determinations of zero levels. Survey observations were carried out by drift scanning the sky between -29{deg} and +90{deg} declination. The fully Nyquist- sampled drift scans were observed in steps of 0.25{deg} to about 2.5{deg} in declination. The rms noise is 12mK in Stokes U and Q.
21639. The DR5 data release of SDSS
- ID:
- ivo://astronet.ru/cas/sdssdr5-photoobjall
- Title:
- The DR5 data release of SDSS
- Short Name:
- sdssdr5-photoobj
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- The Sloan Digital Sky Survey is a project to survey a 10000 square degree area on the Northern sky over a 5 year period. A dedicated 2.5m telescope is specially designed to take wide field (3 degrees in diameter) images using a 5x6 mosaic of 2048x2048 CCD, in five wavelength bands, operating in drift scan mode. The total raw data will exceed 40 TB. A processed subset, of about 1 TB in size, will consist of 1 million spectra, positions and image parameters for over 100 million objects, plus a mini-image centered on each object in every color. The data will be made available to the public after the completion of the survey
21640. The DR5 data release of SDSS
- ID:
- ivo://astronet.ru/cas/sdssdr5-phototag
- Title:
- The DR5 data release of SDSS
- Short Name:
- sdssdr5-phototag
- Date:
- 17 Jun 2006 18:44:05
- Publisher:
- Sternberg Astronomical Institute Virtual Observatory Project
- Description:
- The Sloan Digital Sky Survey is a project to survey a 10000 square degree area on the Northern sky over a 5 year period. A dedicated 2.5m telescope is specially designed to take wide field (3 degrees in diameter) images using a 5x6 mosaic of 2048x2048 CCD, in five wavelength bands, operating in drift scan mode. The total raw data will exceed 40 TB. A processed subset, of about 1 TB in size, will consist of 1 million spectra, positions and image parameters for over 100 million objects, plus a mini-image centered on each object in every color. The data will be made available to the public after the completion of the survey
