- ID:
- ivo://CDS.VizieR/J/ApJ/887/268
- Title:
- Bright QSOs in Southern Hemisphere (QUBRICS)
- Short Name:
- J/ApJ/887/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The study of absorptions along the lines of sight to bright high-z QSOs is an invaluable cosmological tool that provides a wealth of information on the inter-/circum-galactic medium, dark matter, primordial elements, reionization, fundamental constants, and general relativity. Unfortunately, the number of bright (i<~18) QSOs at z>~2 in the southern hemisphere is much lower than that in the north, due to the lack of wide multiwavelength surveys at decl. {delta}<0{deg}, hampering the effectiveness of observations from southern observatories. In this work we present a new method based on Canonical Correlation Analysis to identify such objects, taking advantage of a number of available databases: Skymapper, Gaia DR2, WISE, and 2MASS. Our QSO candidate sample lists 1476 sources with i<18 over 12400deg^2^ in the southern hemisphere. With a preliminary campaign we observed spectroscopically 69 of them, confirming 54 new bright QSOs at z>2.5, corresponding to a success rate of our method of ~80%. Furthermore, we estimate a completeness of ~90% of our sample at completion of our observation campaign. The new QSOs confirmed by this first and the forthcoming campaigns (QUBRICS survey) will be the targets of subsequent studies using higher resolution spectrographs, like ESPRESSO, UVES, and (in the long term) ELT/HIRES.
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- ID:
- ivo://CDS.VizieR/J/ApJS/196/11
- Title:
- Bulge+disk decompositions of SDSS galaxies
- Short Name:
- J/ApJS/196/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We perform two-dimensional, point-spread-function-convolved, bulge+disk decompositions in the g and r bandpasses on a sample of 1123718 galaxies from the Legacy area of the Sloan Digital Sky Survey Data Release Seven. Four different decomposition procedures are investigated which make improvements to sky background determinations and object deblending over the standard SDSS procedures that lead to more robust structural parameters and integrated galaxy magnitudes and colors, especially in crowded environments. We use a set of science-based quality assurance metrics, namely, the disk luminosity-size relation, the galaxy color-magnitude diagram, and the galaxy central (fiber) colors to show the robustness of our structural parameters. The best procedure utilizes simultaneous, two-bandpass decompositions. Bulge and disk photometric errors remain below 0.1mag down to bulge and disk magnitudes of g~19 and r~18.5. We also use and compare three different galaxy fitting models: a pure Sersic model, an n_b_=4 bulge+disk model, and a Sersic (free n_b_) bulge+disk model. The most appropriate model for a given galaxy is determined by the F-test probability. All three catalogs of measured structural parameters, rest-frame magnitudes, and colors are publicly released here.
- ID:
- ivo://CDS.VizieR/J/AJ/142/2
- Title:
- Burrell-Optical-Kepler-Survey (BOKS). I.
- Short Name:
- J/AJ/142/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the initial results of a 40 night contiguous ground-based campaign of time series photometric observations of a 1.39deg^2^ field located within the NASA Kepler Mission field of view. The goal of this pre-launch survey was to search for transiting extrasolar planets and to provide independent variability information of stellar sources. We have gathered a data set containing light curves of 54,687 stars from which we have created a statistical sub-sample of 13,786 stars between 14<r<18.5 and have statistically examined each light curve to test for variability. We present a summary of our preliminary photometric findings including the overall level and content of stellar variability in this portion of the Kepler field and give some examples of unusual variable stars found within. We present a preliminary catalog of 2,457 candidate variable stars, of which 776 show signs of periodicity. We also present three potential exoplanet candidates, all of which should be observable by the Kepler mission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/417/2230
- Title:
- BVRI+SDSS+2MASS and WISE photometry of 289 stars
- Short Name:
- J/MNRAS/417/2230
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present colour transformations for the conversion of the W1 and W2 magnitudes of the Wide-field Infrared Survey Explorer (WISE) photometric system to the Johnson-Cousins BVRI, Sloan Digital Sky Survey gri and Two-Micron All-Sky Survey JHKs photometric systems, for dwarfs.
- ID:
- ivo://CDS.VizieR/J/A+A/608/L8
- Title:
- Calibration of G passband for Gaia DR1
- Short Name:
- J/A+A/608/L8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- On September 2016 the first data from Gaia were released (DR1). The first release included photometry for over 109 sources in the very broad G system. To test the correspondence between G magnitudes in DR1 and the synthetic equivalents derived using spectral energy distributions from observed and model spectrophotometry. To correct the G passband curve and to measure the zero point in the Vega system. Methods. I have computed the synthetic G and Tycho-2 BTVT photometry for a sample of stars using the Next Generation Spectral Library (NGSL) and the Hubble Space Telescope (HST) CALSPEC spectroscopic standards. I have found that the nominal G passband curve is too blue for the DR1 photometry, as shown by the presence of a color with an exponent of 0.783 eliminates the color term. The corrected passband has a Vega zero point of 0.070+/-0.004 magnitudes.
76. CALIFA DR2
- ID:
- ivo://CDS.VizieR/J/A+A/576/A135
- Title:
- CALIFA DR2
- Short Name:
- J/A+A/576/A135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph PMAS/PPak mounted on the 3.5m telescope at the Calar Alto observatory. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the wavelength range 3745-7500{AA} with a spectral resolution of 6.0{AA} (FWHM); and (ii) a medium-resolution V1200 setup covering the wavelength range 3650-4840{AA} with a spectral resolution of 2.3{AA} (FWHM). The sample covers a redshift range between 0.005 and 0.03, with a wide range of properties in the color-magnitude diagram, stellar mass, ionization conditions, and morphological types. All the cubes in the data release were reduced with the latest pipeline, which includes improved spectrophotometric calibration, spatial registration, and spatial resolution. The spectrophotometric calibration is better than 6% and the median spatial resolution is 2.4". In total, the second data release contains over 1.5 million spectra.
- ID:
- ivo://CDS.VizieR/J/ApJS/206/10
- Title:
- CANDELS multiwavelength catalog
- Short Name:
- J/ApJS/206/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multiwavelength ultraviolet to mid-infrared catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc, i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5um from SEDS; 5.8 and 8.0um from SpUDS). The present catalog is F160W-selected and contains 35932 sources over an area of 201.7arcmin^2^ and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/163
- Title:
- Candidate Halpha sources in GBS
- Short Name:
- J/MNRAS/466/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of candidate Halpha emission and absorption line sources and blue objects in the Galactic Bulge Survey (GBS) region. We use a point source catalogue of the GBS fields (two strips of (lxb)=(6{deg}x1{deg}) centred at b=1.5{deg} above and below the Galactic centre), covering the magnitude range 16>=r'>=22.5. We utilize (r'-i', r'-Halpha) colour-colour diagrams to select Halpha emission and absorption line candidates, and also identify blue objects (compared to field stars) using the r'-i' colour index. We identify 1337 Halpha emission line candidates and 336 Halpha absorption line candidates. These catalogues likely contain a plethora of sources, ranging from active (binary) stars, early-type emission line objects, cataclysmic variables (CVs) and low-mass X-ray binaries (LMXBs) to background active galactic nuclei (AGN). The 389 blue objects we identify are likely systems containing a compact object, such as CVs, planetary nebulae and LMXBs. Hot subluminous dwarfs (sdO/B stars) are also expected to be found as blue outliers. Crossmatching our outliers with the GBS X-ray catalogue yields sixteen sources, including seven (magnetic) CVs and one qLMXB candidate among the emission line candidates, and one background AGN for the absorption line candidates. One of the blue outliers is a high state AM CVn system. Spectroscopic observations combined with the multi-wavelength coverage of this area, including X-ray, ultraviolet and (time-resolved) optical and infrared observations, can be used to further constrain the nature of individual sources.
- ID:
- ivo://CDS.VizieR/J/A+A/504/291
- Title:
- Candidate Planetary Nebulae in IPHAS catalog
- Short Name:
- J/A+A/504/291
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out a semi-automated search for planetary nebulae (PNe) in the INT Photometric H-Alpha Survey (IPHAS) catalogue. We present the PN search and the list of selected candidates. We cross correlate the selected candidates with a number of existing infrared galactic surveys in order to gain further insight into the nature of the candidates. Spectroscopy of a subset of objects is used to estimate the number of PNe present in the entire candidate list. The overall aim of the IPHAS PN project is to carry out a deep census of PNe in the northern Galactic plane, an area where PN detections are clearly lacking. The PN search is carried out on the IPHAS photometric catalogues. The candidate selection is based on the IPHAS and 2MASS/UKIDSS colours of the objects and the final candidate selection is made visually.
- ID:
- ivo://CDS.VizieR/J/A+A/444/643
- Title:
- Candidate spectroscopic binaries in SDSS
- Short Name:
- J/A+A/444/643
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have examined the radial velocity data for stars spectroscopically observed by the Sloan Digital Sky Survey (SDSS) more than once to investigate the incidence of spectroscopic binaries, and to evaluate the accuracy of the SDSS stellar radial velocities.