- ID:
- ivo://CDS.VizieR/II/358
- Title:
- SkyMapper Southern Sky Survey. DR1.1
- Short Name:
- II/358
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first data release of the SkyMapper Southern Survey, a hemispheric survey carried out with the SkyMapper Telescope at Siding Spring Observatory in Australia. Here, we present the survey strategy, data processing, catalogue construction, and database schema. The first data release dataset includes over 66000 images from the Shallow Survey component, covering an area of 17200 deg^2^ in all six SkyMapper passbands uvgriz, while the full area covered by any passband exceeds 20000 deg^2^. The catalogues contain over 285 million unique astrophysical objects, complete to roughly 18mag in all bands. We compare our griz point-source photometry with Pan-STARRS1 first data release and note an RMS scatter of 2%. The internal reproducibility of SkyMapper photometry is on the order of 1%. Astrometric precision is better than 0.2arcsec based on comparison with Gaia first data release. We describe the end-user database, through which data are presented to the world community, and provide some illustrative science queries.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/794/120
- Title:
- Sloan Digital Sky Survey coadd. Stripe 82
- Short Name:
- J/ApJ/794/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present details of the construction and characterization of the coaddition of the Sloan Digital Sky Survey (SDSS) Stripe 82 ugriz imaging data. This survey consists of 275 deg^2^ of repeated scanning by the SDSS camera over -50{deg}<={alpha}<=60{deg} and -1.25{deg}<={delta}<= +1.25{deg} centered on the Celestial Equator. Each piece of sky has ~20 runs contributing and thus reaches ~2mag fainter than the SDSS single pass data, i.e., to r~23.5 for galaxies. We discuss the image processing of the coaddition, the modeling of the point-spread function (PSF), the calibration, and the production of standard SDSS catalogs. The data have an r-band median seeing of 1.1'' and are calibrated to <=1%. Star color-color, number counts, and PSF size versus modeled size plots show that the modeling of the PSF is good enough for precision five-band photometry. Structure in the PSF model versus magnitude plot indicates minor PSF modeling errors, leading to misclassification of stars as galaxies, as verified using VVDS spectroscopy. There are a variety of uses for this wide-angle deep imaging data, including galactic structure, photometric redshift computation, cluster finding and cross wavelength measurements, weak lensing cluster mass calibrations, and cosmic shear measurements.
- ID:
- ivo://CDS.VizieR/J/AJ/121/2308
- Title:
- Sloan Digital Sky Survey quasar photometry
- Short Name:
- J/AJ/121/2308
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an empirical investigation of the colors of quasars in the Sloan Digital Sky Survey (SDSS) photometric system. The sample studied includes 2625 quasars with SDSS photometry: 1759 quasars found during SDSS spectroscopic commissioning and SDSS follow-up observations on other telescopes, 50 matches to FIRST quasars, 573 matches to quasars from the NASA Extragalactic Database, and 243 quasars from two or more of these sources. The quasars are distributed in a 2.5{deg} wide stripe centered on the celestial equator covering ~529deg^2^. Positions (accurate to 0.2") and SDSS magnitudes are given for the 898 quasars known prior to SDSS spectroscopic commissioning.
- ID:
- ivo://CDS.VizieR/V/154
- Title:
- Sloan Digital Sky Surveys (SDSS), Release 16 (DR16)
- Short Name:
- V/154
- Date:
- 25 Feb 2022 11:21:42
- Publisher:
- CDS
- Description:
- This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar").
- ID:
- ivo://CDS.VizieR/J/ApJS/215/15
- Title:
- SMaSH+: observations and companion detection
- Short Name:
- J/ApJS/215/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multiplicity is one of the most fundamental observable properties of massive O-type stars and offers a promising way to discriminate between massive star formation theories. Nevertheless, companions at separations between 1 and 100 milliarcsec (mas) remain mostly unknown due to intrinsic observational limitations. At a typical distance of 2kpc, this corresponds to projected physical separations of 2-200AU. The Southern MAssive Stars at High angular resolution survey (SMaSH+) was designed to fill this gap by providing the first systematic interferometric survey of Galactic massive stars. We observed 117 O-type stars with VLTI/PIONIER and 162 O-type stars with NACO/Sparse Aperture Masking (SAM), probing the separation ranges 1-45 and 30-250mas and brightness contrasts of {Delta}H<4 and {Delta}H<5, respectively. Taking advantage of NACO's field of view, we further uniformly searched for visual companions in an 8" radius down to {Delta}H=8. This paper describes observations and data analysis, reports the discovery of almost 200 new companions in the separation range from 1mas to 8" and presents a catalog of detections, including the first resolved measurements of over a dozen known long-period spectroscopic binaries. Excluding known runaway stars for which no companions are detected, 96 objects in our main sample ({delta}<0{deg}; H<7.5) were observed both with PIONIER and NACO/SAM. The fraction of these stars with at least one resolved companion within 200mas is 0.53. Accounting for known but unresolved spectroscopic or eclipsing companions, the multiplicity fraction at separation {rho}<8" increases to f_m_=0.91+/-0.03. The nine non-thermal radio emitters observed by SMaSH+ are all resolved, including the newly discovered pairs HD 168112 and CPD-47{deg}2963.
- ID:
- ivo://CDS.VizieR/J/ApJS/240/1
- Title:
- SMUDGes. I. First results in the Coma Cluster
- Short Name:
- J/ApJS/240/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a homogeneous catalog of 275 large (effective radius >~5.3") ultra-diffuse galaxy (UDG) candidates lying within an ~290deg^2^ region surrounding the Coma Cluster. The catalog results from our automated postprocessing of data from the Legacy Surveys, a three-band imaging survey covering 14000deg^2^ of the extragalactic sky. We describe a pipeline that identifies UDGs and provides their basic parameters. The survey is as complete in these large UDGs as previously published UDG surveys of the central region of the Coma Cluster. We conclude that the majority of our detections are at roughly the distance of the Coma Cluster, implying effective radii >=2.5kpc, and that our sample contains a significant number of analogs of DF44 (SMDG1300580+265835), where the effective radius exceeds 4kpc, both within the cluster and in the surrounding field. The g-z color of our UDGs spans a large range, suggesting that even large UDGs may reflect a range of formation histories. A majority of the UDGs are consistent with being lower stellar mass analogs of red sequence galaxies, but we find both red and blue UDG candidates in the vicinity of the Coma Cluster and a relative overabundance of blue UDG candidates in the lower-density environments and the field. Our eventual processing of the full Legacy Surveys data will produce the largest, most homogeneous sample of large UDGs.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/13
- Title:
- SNe Ia light curves for the LSQ-CSP sample
- Short Name:
- J/ApJS/219/13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The La Silla/QUEST Variability Survey (LSQ) and the Carnegie Supernova Project (CSP II) are collaborating to discover and obtain photometric light curves for a large sample of low-redshift (z<0.1) Type Ia supernovae (SNe Ia). The supernovae are discovered in the LSQ survey using the 1m ESO Schmidt telescope at the La Silla Observatory with the 10 square degree QUEST camera. The follow-up photometric observations are carried out using the 1m Swope telescope and the 2.5m du Pont telescopes at the Las Campanas Observatory. This paper describes the survey, discusses the methods of analyzing the data, and presents the light curves for the first 31 SNe Ia obtained in the survey. The SALT 2.4 supernova light-curve fitter was used to analyze the photometric data, and the Hubble diagram for this first sample is presented. The measurement errors for these supernovae averaged 4%, and their intrinsic spread was 14%.
- ID:
- ivo://CDS.VizieR/J/ApJ/738/162
- Title:
- SN Ia candidates from the SDSS-II SN Survey
- Short Name:
- J/ApJ/738/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the three-year Sloan Digital Sky Survey II (SDSS-II) Supernova (SN) Survey data and identify a sample of 1070 photometric Type Ia supernova (SN Ia) candidates based on their multiband light curve data. This sample consists of SN candidates with no spectroscopic confirmation, with a subset of 210 candidates having spectroscopic redshifts of their host galaxies measured while the remaining 860 candidates are purely photometric in their identification. We describe a method for estimating the efficiency and purity of photometric SN Ia classification when spectroscopic confirmation of only a limited sample is available, and demonstrate that SN Ia candidates from SDSS-II can be identified photometrically with ~91% efficiency and with a contamination of ~6%. Although this is the largest uniform sample of SN candidates to date for studying photometric identification, we find that a larger spectroscopic sample of contaminating sources is required to obtain a better characterization of the background events. A Hubble diagram using SN candidates with no spectroscopic confirmation, but with host galaxy spectroscopic redshifts, yields a distance modulus dispersion that is only ~20%-40% larger than that of the spectroscopically confirmed SN Ia sample alone with no significant bias. A Hubble diagram with purely photometric classification and redshift-distance measurements, however, exhibits biases that require further investigation for precision cosmology.
- ID:
- ivo://CDS.VizieR/J/AJ/116/1
- Title:
- Southern Sky Redshift Survey
- Short Name:
- J/AJ/116/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report redshifts, magnitudes, and morphological classifications for 5369 galaxies with m_B_<=15.5 and for 57 galaxies fainter than this limit, in two regions covering a total of 1.70 sr in the southern celestial hemisphere. The galaxy catalog is drawn primarily from the list of nonstellar objects identified in the Hubble Space Telescope Guide Star Catalog (GSC). The galaxies have positions accurate to ~1" and magnitudes with an rms scatter of ~0.3mag. We compute magnitudes (m_SSRS2_) from the relation between instrumental GSC magnitudes and the photometry by Lauberts & Valentijn. From a comparison with CCD photometry, we find that our system is homogeneous across the sky and corresponds to magnitudes measured at the isophotal level ~26mag/arcsec^2^. The precision of the radial velocities is ~40km/s, and the redshift survey is more than 99% complete to the m_SSRS2_=15.5mag limit. This sample is in the direction opposite that of the CfA2; in combination the two surveys provide an important database for studies of the properties of galaxies and their large-scale distribution in the nearby universe.
- ID:
- ivo://CDS.VizieR/J/ApJS/81/413
- Title:
- Southern sky survey of 1355 spiral galaxies
- Short Name:
- J/ApJS/81/413
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data from photometric and spectroscopic observations of 1355 southern spiral galaxies are presented and used to determine their distances and peculiar velocities via the Tully-Fisher (TF) relation. I-band CCD surface photometry was carried out using the 1-m and 3.9-m telescopes at Siding Spring Observatory. H-alpha rotation curves for 965 galaxies and 551 H I profiles are presented. The physical parameters, photometric and velocity data, distances, and peculiar velocities of the galaxies are presented in tabular form. The mean distance, systemic velocity, and average peculiar velocity of 24 clusters in the sample are given. TF diagrams are presented for each cluster.