- ID:
- ivo://CDS.VizieR/J/ApJ/510/659
- Title:
- Size and Structure of AGN in NGC 5548
- Short Name:
- J/ApJ/510/659
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of 3 yr of ground-based observations of the Seyfert 1 galaxy NGC 5548, which, combined with previously reported data, yield optical continuum and broad-line H{beta} light curves for a total of 8 yr. The light curves consist of over 800 points, with a typical spacing of a few days between observations. During this 8 yr period, the nuclear continuum has varied by more than a factor of 7, and the H{beta} emission line has varied by a factor of nearly 6. The H{beta} emission line responds to continuum variations with a time delay or lag of {=~}10--20 days, the precise value varying somewhat from year to year. We find some indications that the lag varies with continuum flux in the sense that the lag is larger when the source is brighter.
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- ID:
- ivo://CDS.VizieR/J/AJ/142/199
- Title:
- Sizes and luminosities of stellar systems
- Short Name:
- J/AJ/142/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a combined imaging and spectroscopic survey of the nearby central cluster galaxy, M87, to assemble a sample of 34 confirmed UltraCompact Dwarfs (UCDs) with half-light radii of >=10pc measured from Hubble Space Telescope (HST) images. This doubles the existing sample in M87, making it the largest such sample for any galaxy, while extending the detection of UCDs to unprecedentedly low luminosities (MV=-9). With this expanded sample, we find no correlation between size and luminosity, in contrast to previous suggestions, and no general correlation between size and galactocentric distance. We explore the relationships between UCDs, less luminous extended clusters (including faint fuzzies), Globular Clusters (GCs), as well as early-type galaxies and their nuclei, assembling an extensive new catalog of sizes and luminosities for stellar systems. Most of the M87 UCDs follow a tight color-magnitude relation, offset from the metal-poor GCs. This, along with kinematical differences, demonstrates that most UCDs are a distinct population from normal GCs, and not simply a continuation to larger sizes and higher luminosities. The UCD color-magnitude trend couples closely with that for Virgo dwarf elliptical nuclei. We conclude that the M87 UCDs are predominantly stripped nuclei. The brightest and reddest UCDs may be the remnant nuclei of more massive galaxies while a subset of the faintest UCDs may be tidally limited and related to more compact star clusters. In the broader context of galaxy assembly, blue UCDs may trace halo build-up by accretion of low-mass satellites, while red UCDs may be markers of metal-rich bulge formation in larger galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/639
- Title:
- Sizes of Lyman alpha emitters at z=3.1
- Short Name:
- J/ApJ/705/639
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a rest-frame ultraviolet analysis of ~120 z~3.1 Lyman Alpha Emitters (LAEs) in the Extended Chandra Deep Field South. Using Hubble Space Telescope (HST) images taken as part of the Galaxy Evolution From Morphology and SEDS (GEMS) survey, Great Observatories Origins Deep Survey (GOODS), and Hubble Ultradeep Field surveys, we analyze the sizes of LAEs, as well as the spatial distribution of their components, which are defined as distinct clumps of UV-continuum emission. We set an upper limit of ~1kpc (~0.1") on the rms offset between the centroids of the continuum and Ly{alpha} emission. Most of the multi-component LAEs identified in shallow frames become connected in deeper images, suggesting that the majority of the rest-UV "clumps" are individual star-forming regions within a single system.
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/851/48
- Title:
- SLACS. XIII. Galaxy-scale strong lens candidates
- Short Name:
- J/ApJ/851/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the full sample of 118 galaxy-scale strong-lens candidates in the Sloan Lens ACS (SLACS) Survey for the Masses (S4TM) Survey, which are spectroscopically selected from the final data release of the Sloan Digital Sky Survey. Follow-up Hubble Space Telescope (HST) imaging observations confirm that 40 candidates are definite strong lenses with multiple lensed images. The foreground-lens galaxies are found to be early-type galaxies (ETGs) at redshifts 0.06-0.44, and background sources are emission-line galaxies at redshifts 0.22-1.29. As an extension of the SLACS Survey, the S4TM Survey is the first attempt to preferentially search for strong-lens systems with relatively lower lens masses than those in the pre-existing strong-lens samples. By fitting HST data with a singular isothermal ellipsoid model, we find that the total projected mass within the Einstein radius of the S4TM strong-lens sample ranges from 3x10^10^M_{sun}_ to 2x10^11^M_{sun}_. In Shu+ (2015ApJ...803...71S), we have derived the total stellar mass of the S4TM lenses to be 5x10^10^M_{sun}_ to 1x10^12^M_{sun}_. Both the total enclosed mass and stellar mass of the S4TM lenses are on average almost a factor of 2 smaller than those of the SLACS lenses, which also represent the typical mass scales of the current strong-lens samples. The extended mass coverage provided by the S4TM sample can enable a direct test, with the aid of strong lensing, for transitions in scaling relations, kinematic properties, mass structure, and dark-matter content trends of ETGs at intermediate-mass scales as noted in previous studies.
- 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/ApJ/663/573
- Title:
- Sloan gi light curves of HAT-TR-205-012
- Short Name:
- J/ApJ/663/573
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We derive masses and radii for both components in the single-lined eclipsing binary HAT-TR-205-013, which consists of an F7 V primary and a late M dwarf secondary. The system's period is short, P=2.230736+/-0.000010 days, with an orbit indistinguishable from circular, e=0.012+/-0.021. We demonstrate generally that the surface gravity of the secondary star in a single-lined binary undergoing total eclipses can be derived from characteristics of the light curve and spectroscopic orbit.
- ID:
- ivo://CDS.VizieR/J/ApJ/725/2017
- Title:
- Sloan i-band light curve of HAT-P-24
- Short Name:
- J/ApJ/725/2017
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of HAT-P-24b, a transiting extrasolar planet orbiting the moderately bright V=11.818 F8 dwarf star GSC 0774-01441, with a period P=3.3552464+/-0.0000071 days, transit epoch T_c_=2455216.97669+/-0.00024(BJD), and transit duration 3.653+/-0.025hr. The host star has a mass of 1.191+/-0.042M_{sun}_, radius of 1.317+/-0.068R_{sun}_, effective temperature 6373+/-80K, and a low metallicity of [Fe/H]=-0.16+/-0.08. The planetary companion has a mass of 0.681+/-0.031M_J_ and radius of 1.243+/-0.072R_J_ yielding a mean density of 0.439+/-0.069g/cm^3^. By repeating our global fits with different parameter sets, we have performed a critical investigation of the fitting techniques used for previous Hungarian-made Automated Telescope planetary discoveries. We find that the system properties are robust against the choice of priors.