- ID:
- ivo://CDS.VizieR/J/MNRAS/452/765
- Title:
- White dwarf candidates using LAMOST DR3
- Short Name:
- J/MNRAS/452/765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In previous work by Gentile Fusillo et al., we developed a selection method for white dwarf candidates which makes use of photometry, colours and proper motions to calculate a probability of being a white dwarf (P_WD_). The application of our method to the Sloan Digital Sky Survey (SDSS) data release 10 resulted in =~ 66000 photometrically selected objects with a derived P_WD_, approximately =~21000 of which are high-confidence white dwarf candidates. Here, we present an independent test of our selection method based on a sample of spectroscopically confirmed white dwarfs from the Large Sky Area Multi-Fiber Spectroscopic Telescope (LAMOST) survey. We do this by cross-matching all our =~66000 SDSS photometric white dwarf candidates with the over 4 million spectra available in the third data release of LAMOST. This results in 1673 white dwarf candidates with no previous SDSS spectroscopy, but with available LAMOST spectra. Among these objects, we identify 309 genuine white dwarfs. We find that our P_WD_ can efficiently discriminate between confirmed LAMOST white dwarfs and contaminants. Our white dwarf candidate selection method can be applied to any multiband photometric survey and in this work we conclusively confirm its reliability in selecting white dwarfs without recourse to spectroscopy. We also discuss the spectroscopic completeness of white dwarfs in LAMOST, as well as deriving effective temperatures, surface gravities and masses for the hydrogen-rich atmosphere white dwarfs in the newly identified LAMOST sample.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/927
- Title:
- Wide-field optical imaging of 4 fields
- Short Name:
- J/MNRAS/416/927
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present u-, g-, r-, i- and z-band optical images and associated catalogues taken primarily with the Isaac Newton Telescope Wide Field Camera on the European Large Area ISO Survey (ELAIS) N1 and N2, First Look Survey and Lockman Hole fields comprising a total of 1000h of integration time over 80deg^2^ and approximately 4.3 million objects. In this paper we outline the observations and data processing and characterize the completeness, reliability, photometric and astrometric accuracy of this data set. All images have been photometrically calibrated using the Sloan Digital Sky Survey and a uniform and homogeneous data set is composed over all the observed fields. Magnitude limits are u, g, r, i, z of 23.9, 24.5, 24.0, 23.3, 22.0 (AB, 5{sigma}). These data have been used for optical identification of past and ongoing projects including the surveys ELAIS, Spitzer Wide-Area Infrared Extragalactic Survey, Spitzer Extragalactic Representative Volume Survey and Herschel Multi-tiered Extragalactic Survey.
- ID:
- ivo://CDS.VizieR/J/ApJ/819/1
- Title:
- Wide-field photometry of the GC Palomar 5
- Short Name:
- J/ApJ/819/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of wide-field photometric surveys of the Palomar 5 globular cluster and its stellar stream, based on g- and r-band measures together with narrow-band DDO 51 photometry. In this first study, we use the deep (g, r) data to measure the incidence of gaps and peaks along the stream. Examining the star-counts profile of the stream plus contaminating populations, we find no evidence for significant underdensities, and find only a single significant overdensity. This is at odds with earlier studies based on matched-filter maps derived from shallower SDSS data if the contaminating population possesses plausible spatial properties. The lack of substantial substructure along the stream may be used in future dynamical simulations to examine the incidence of dark matter sub-halos in the Galactic halo. We also present a measurement of the relative distances along the stream, which we use to create the deepest wide-field map of this system to date. Universe}
- ID:
- ivo://CDS.VizieR/J/AJ/156/137
- Title:
- Wide-orbit Exoplanet search with IR Direct imaging
- Short Name:
- J/AJ/156/137
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report results from the Wide-orbit Exoplanet search with InfraRed Direct imaging, or WEIRD, a survey designed to search for Jupiter-like companions on very wide orbits (1000-5000 au) around young stars (<120 Myr) that are known members of moving groups in the solar neighborhood (<70 pc). Companions that share the same age, distance, and metallicity as their host while being on large enough orbits to be studied as "isolated" objects make prime targets for spectroscopic observations, and they are valuable benchmark objects for exoplanet atmosphere models. The search strategy is based on deep imaging in multiple bands across the near-infrared domain. For all 177 objects of our sample, z'_ab_, J, [3.6], and [4.5] images were obtained with CFHT/MegaCam, GEMINI/GMOS, CFHT/WIRCam, GEMINI/Flamingos-2, and Spitzer/IRAC. Using this set of four images per target, we searched for sources with red z'_ab_ and [3.6]-[4.5] colors, typically reaching good completeness down to 2 M_Jup_ companions, while going down to 1 M_Jup_ for some targets, at separations of 1000-5000 au. The search yielded four candidate companions with the expected colors, but they were all rejected through follow-up proper motion observations. Our results constrain the occurrence of 1-13 M_Jup_ planetary-mass companions on orbits with a semimajor axis between 1000 and 5000 au at less than 0.03, with a 95% confidence level.
- ID:
- ivo://CDS.VizieR/J/MNRAS/401/1429
- Title:
- WiggleZ dark energy survey (DR1)
- Short Name:
- J/MNRAS/401/1429
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The WiggleZ Dark Energy Survey is a survey of 240000 emission-line galaxies in the distant Universe, measured with the AAOmega spectrograph on the 3.9-m Anglo-Australian Telescope (AAT). The primary aim of the survey is to precisely measure the scale of baryon acoustic oscillations (BAO) imprinted on the spatial distribution of these galaxies at look-back times of 4-8Gyr. The target galaxies are selected using ultraviolet (UV) photometry from the Galaxy Evolution Explorer satellite, with a flux limit of NUV<22.8mag. We also require that the targets are detected at optical wavelengths, specifically in the range 20.0<r<22.5mag. We use the Lyman break method applied to the UV colours, with additional optical colour limits, to select high-redshift galaxies. The galaxies generally have strong emission lines, permitting reliable redshift measurements in relatively short exposure times on the AAT. The median redshift of the galaxies is z_med_=0.6. The redshift range containing 90 per cent of the galaxies is 0.2<z<1.0. The survey will sample a volume of ~1Gpc^3^ over a projected area on the sky of 1000deg^2^, with an average target density of 350deg^-2^.
- ID:
- ivo://CDS.VizieR/J/MNRAS/474/4151
- Title:
- WiggleZ Dark Energy Survey final DR
- Short Name:
- J/MNRAS/474/4151
- Date:
- 02 Mar 2022 00:09:00
- Publisher:
- CDS
- Description:
- The WiggleZ Dark Energy Survey measured the redshifts of over 200000 ultraviolet (UV)-selected (N_UV_<22.8mag) galaxies on the Anglo-Australian Telescope. The survey detected the baryon acoustic oscillation signal in the large-scale distribution of galaxies over the redshift range 0.2<z<1.0, confirming the acceleration of the expansion of the Universe and measuring the rate of structure growth within it. Here, we present the final data release of the survey: a catalogue of 225415 galaxies and individual files of the galaxy spectra. We analyse the emission-line properties of these UV-luminous Lyman-break galaxies by stacking the spectra in bins of luminosity, redshift, and stellar mass. The most luminous (-25mag<M_FUV_< -22mag) galaxies have very broad H{beta} emission from active nuclei, as well as a broad second component to the [OIII] (495.9nm, 500.7nm) doublet lines that is blueshifted by 100km/s, indicating the presence of gas outflows in these galaxies. The composite spectra allow us to detect and measure the temperature-sensitive [OIII] (436.3nm) line and obtain metallicities using the direct method. The metallicities of intermediate stellar mass (8.8<log(M*/M_{sun}_)<10) WiggleZ galaxies are consistent with normal emission-line galaxies at the same masses. In contrast, the metallicities of high stellar mass (10<log(M*/M_{sun}_)<12) WiggleZ galaxies are significantly lower than for normal emission-line galaxies at the same masses. This is not an effect of evolution as the metallicities do not vary with redshift; it is most likely a property specific to the extremely UV-luminous WiggleZ galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/620/A51
- Title:
- WIRCam Ultra Deep Survey photometric catalogs
- Short Name:
- J/A+A/620/A51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The aim of this paper is to introduce the WIRCam Ultra Deep Survey (WUDS), a near-IR photometric survey carried out at the CFH Telescope in the field of the CFHTLS-D3 field (Groth Strip). WUDS includes four near-IR bands (Y, J, H and Ks) over a field of view of ~400arcmin^2^. The typical depth of WUDS data reaches between ~26.8 in Y and J, and ~26 in H and Ks (AB, 3{sigma} in 1.3" aperture), whereas the corresponding depth of the CFHTLS-D3 images in this region ranges between 28.6 and 29 in ugr, 28.2 in i and 27.1 in z (same S/N and aperture). The area and depth of this survey were specifically tailored to set strong constraints on the cosmic star formation rate and the luminosity function brighter or around L* in the z~6-10 redshift domain, although these data are also useful for a variety of extragalactic projects. This first paper is intended to present the properties of the public WUDS survey in details: catalog building, completeness and depth, number counts, photometric redshifts, and global properties of the galaxy population. We have also concentrated on the selection and characterization of galaxy samples at z~[4.5-7] in this field. For these purposes, we include an adjacent shallower area of ~1260arcmin^2^ in this region, extracted from the WIRCam Deep Survey (WIRDS), and observed in J, H and Ks bands. UV luminosity functions were derived at z~5 and z~6 taking advantage from the fact that WUDS covers a particularly interesting regime at intermediate luminosities, which allows a combined determination of M* and {PHI}* with increased accuracy. Our results on the luminosity function are consistent with a small evolution of both M* and {PHI}* between z=5 and z=6, irrespective of the method used to derive them, either photometric redshifts applied to blindly-selected dropout samples or the classical Lyman Break Galaxy color-preselected samples. Our results lend support to higher {PHI}* determinations at z=6 than usually reported. The selection and combined analysis of different galaxy samples at z>=7 will be presented in a forthcoming paper, as well as the evolution of the UV luminosity function between z~4.5 and 9. WUDS is intended to provide a robust database in the near-IR for the selection of targets for detailed spectroscopic studies, in particular for the EMIR/GTC GOYA Survey.
- ID:
- ivo://CDS.VizieR/IX/1
- Title:
- Wisconsin soft X-ray diffuse background all-sky Survey
- Short Name:
- IX/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains all-sky survey of the soft X-ray diffuse background and the count-rate data from which the maps were made for the ten flights included in the survey. It contains 40 files in the machine-readable version and includes documentation and utility subroutines. The data files contain different band maps (B, C, M, M1, M2, I, J, 2-6 keV) in a 0 degree-centered Aitoff projection, in a 180-degree-centered Aitoff projection, in a north polar projection, and in a south polar projection. Lookup tables in the form of FITS images are provided for conversion between pixel coordinates and Galactic coordinates for the various projections. The bands are: B = 130-188eV C = 160-284eV M1 = 440-930eV M2 = 600-1100eV I = 770-1500eV J = 1100-2200eV 2-6keV = 1800-6300eV
- ID:
- ivo://irsa.ipac/WISE/Catalog/All-Sky/Metadata
- Title:
- WISE All-Sky Atlas Metadata Table
- Short Name:
- WISE All-Sky MT
- Date:
- 01 Oct 2018 20:27:16
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- NASA's Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010) mapped the sky at 3.4, 4.6, 12, and 22 μm (W1, W2, W3, W4) in 2010 with an angular resolution of 6.1", 6.4", 6.5", & 12.0" in the four bands. WISE achieved 5σ point source sensitivities better than 0.08, 0.11, 1 and 6 mJy in unconfused regions on the ecliptic in the four bands. Sensitivity improves toward the ecliptic poles due to denser coverage and lower zodiacal background. The All-Sky Release includes all data taken during the WISE full cryogenic mission phase, 7 January 2010 to 6 August 2010, that were processed with improved calibrations and reduction algorithms. Release data products include an Atlas of 18,240 match-filtered, calibrated and coadded image sets, a Source Catalog containing positional and photometric information for over 563 million objects detected on the WISE images, and an Explanatory Supplement that is a guide to the format, content, characteristics and cautionary notes for the WISE All-Sky Release products. The WISE All-Sky Data Release Single-exposure Source Working Database contains positions and brightness information, uncertainties, time of observation and assorted quality flags for 9,479,433,101 "sources" detected on the individual WISE 7.7s (W1 and W2) and 8.8s (W3 and W4) Single-exposure images. Because WISE scanned every point on the sky multiple times, the Single-exposure Database contains multiple, independent measurements of objects on the sky. Entries in the Single-exposure Source Table include detections of real astrophysical objects, as well as spurious detections of low SNR noise excursions, transient events such as hot pixels, charged particle strikes and satellite streaks, and image artifacts light from bright sources including the moon. Many of the unreliable detections are flagged in the Single-exposure Table, but they have not been filtered out as they were for the Source Catalog. Therefore, the Table must be used with caution. Users are strongly encouraged to read the Cautionary Notes before using the Table.
- ID:
- ivo://CDS.VizieR/II/311
- Title:
- WISE All-Sky Data Release
- Short Name:
- II/311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Wide-field Infrared Survey Explorer (WISE; see Wright et al. 2010AJ....140.1868W) is a NASA Medium Class Explorer mission that conducted a digital imaging survey of the entire sky in the 3.4, 4.6, 12 and 22um mid-infrared bandpasses (hereafter W1, W2, W3 and W4). WISE will produce and release to the world astronomical and educational communities and general public a digital Image Atlas covering the sky in the four survey bands, and a reliable Source Catalog containing accurate photometry and astrometry for over 300 million objects. The WISE Catalog and Atlas will enable a broad variety of research efforts ranging from the search for the closest stars and brown dwarfs to the most luminous galaxies in the Universe. WISE science data products will serve as an important reference data set for planning observations and interpreting data obtained with future ground and space-borne observatories, such as JWST. WISE was launched on 2009-12-14 from Vandenberg SLC2W.