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- ID:
- ivo://nasa.heasarc/fsvsclustr
- Title:
- Faint Sky Variability Survey Catalog of Galaxy Clusters and Rich Groups
- Short Name:
- FSVSClusGR
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Faint Sky Variability Survey Catalog of Galaxy Clusters and Rich Groups contains a a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey (FSVS). The clusters have been identified using a fully automated, semi-parametric technique based on a maximum likelihood approach applied to Voronoi tessellation, and enhanced by color discrimination. The sample covers a wide range of richness, has a density of ~28 clusters per square degree, and spans a range of estimated redshifts of 0.05 < z < 0.9 with mean <z> = 0.345. Assuming the presence of a cluster red sequence, the uncertainty of the estimated cluster redshifts is assessed to be sigma ~ 0.03. Containing over 100 clusters with z > 0.6, the catalog contributes substantially to the current total of optically-selected, intermediate-redshift clusters, and complements the existing, usually X-ray selected, samples. The FSVS fields are accessible for observation throughout the whole year, making them particularly suited for large follow-up programs. The construction of this FSVS Cluster Catalogue completes a fundamental component of the authors' continuing program to investigate the environments of quasars and the chemical evolution of galaxies. The present table contains the list of all clusters with their basic parameters. This table was created by the HEASARC in July 2006 based on the table cluster_catalogue.txt copied from the first author's website <a href="https://web.archive.org/web/20100318044103/www-astro.physics.ox.ac.uk/~iks/FSVScatalogue/">https://web.archive.org/web/20100318044103/www-astro.physics.ox.ac.uk/~iks/FSVScatalogue/</a> (no longer available, unfortunately). Refer instead to <a href="https://cdsarc.unistra.fr/viz-bin/cat/J/MNRAS/369/1334">https://cdsarc.unistra.fr/viz-bin/cat/J/MNRAS/369/1334</a> for the data files and to <a href="https://www.noao.edu/survey-archives/fsvs/">https://www.noao.edu/survey-archives/fsvs/</a> for additional information about the survey. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/AJ/104/1765
- Title:
- Faint Stroemgren photometry
- Short Name:
- J/AJ/104/1765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have initiated a faint photometric survey in the Stroemgren system covering ~1 square degree and including 1238 objects in order to develop samples which best probe the thick disk population. The catalog of observations are presented here. They were acquired without kinematic or metallicity biases and are complete to V=17.3-18.5, depending on the field, for 810 early to relatively late type (K0 V or G5 III) stars. Photometric metallicities were derived for 508 stars and indicate a metal-poor stellar population, consistent with a mixture of thick disk and halo stars. While the Stroemgren u-band was not part of the survey, follow-up u-band observations of 32 survey objects indicate that intermediate color survey stars (0.3<=b-y<=0.5) are main-sequence or slightly evolved stars, while redder survey stars (b-y>=0.5) are giants. The survey catalog is available in electronic form upon request.
- ID:
- ivo://CDS.VizieR/J/AJ/152/91
- Title:
- Faint UBVRI standard stars at +50{deg} declination
- Short Name:
- J/AJ/152/91
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Precise and accurate CCD-based UBVRI photometry is presented for ~2000 stars distributed around the sky in a declination zone centered approximately at +50{deg}. Their photometry has been calibrated to the standard Johnson UBV and Kron-Cousins RI systems through observations of the UBVRI standard stars presented in the various works of Landolt. The magnitude and color range for these stars are 12<~V<~22 and -0.3<~(B-V)<~1.8, respectively. Each star averages 13 measures in each UBVRI filter from data taken on 41 different photometric nights obtained over a 21 month period. Hence, there now exists a network of faint UBVRI photometric standard stars centered on the declination zones {delta}=-50{deg}, 0{deg}, and +50{deg}.
- ID:
- ivo://CDS.VizieR/J/ApJ/725/1215
- Title:
- Faint UV standards from Swift, GALEX and SDSS
- Short Name:
- J/ApJ/725/1215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At present, the precision of deep ultraviolet photometry is somewhat limited by the dearth of faint ultraviolet standard stars. In an effort to improve this situation, we present a uniform catalog of 11 new faint (u~17) ultraviolet standard stars. High-precision photometry of these stars has been taken from the Sloan Digital Sky Survey and Galaxy Evolution Explorer archives and combined with new data from the Swift Ultraviolet Optical Telescope to provide precise photometric measures extending from the near-infrared to the far-ultraviolet. These stars were chosen because they are known to be hot (20000<T_eff_<50000K) DA white dwarfs with published Sloan spectra that should be photometrically stable. This careful selection allows us to compare the combined photometry and Sloan spectroscopy to models of pure hydrogen atmospheres to both constrain the underlying properties of the white dwarfs and test the ability of white dwarf models to predict the photometric measures.
- ID:
- ivo://CDS.VizieR/J/ApJ/651/1098
- Title:
- Faint X-ray sources in Terzan 5
- Short Name:
- J/ApJ/651/1098
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report our analysis of a Chandra X-ray observation of the rich globular cluster Terzan 5, in which we detect 50 sources to a limiting 1.0-6keV X-ray luminosity of 3x10^31^ergs/s within the half-mass radius of the cluster. Thirty-three of these have LX>10^32^ergs/s, the largest number yet seen in any globular cluster. In addition to the quiescent low-mass X-ray binary (LMXB; identified by Wijnands et al., 2005ApJ...618..883W), another 12 relatively soft sources may be quiescent LMXBs. We compare the X-ray colors of the harder sources in Terzan 5 to the Galactic center sources studied by Muno and collaborators (2003, Cat. <J/ApJ/589/225>) and find the Galactic center sources to have harder X-ray colors, indicating a possible difference in the populations. We cannot clearly identify a metallicity dependence in the production of low-luminosity X-ray binaries in Galactic globular clusters, but a metallicity dependence of the form suggested by Jordan et al. (2004, Cat. <J/ApJ/613/270>) for extragalactic LMXBs is consistent with our data.
- ID:
- ivo://CDS.VizieR/J/PASP/128/G4502
- Title:
- False alarms in Kepler planet candidate cat.
- Short Name:
- J/PASP/128/G4502
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new automated method to identify instrumental features masquerading as small, long-period planets in the Kepler planet candidate catalog. These systematics, mistakenly identified as planet transits, can have a strong impact on occurrence rate calculations because they cluster in a region of parameter space where Kepler's sensitivity to planets is poor. We compare individual transit-like events to a variety of models of real transits and systematic events and use a Bayesian information criterion to evaluate the likelihood that each event is real. We describe our technique and test its performance on simulated data. Results from this technique are incorporated in the Kepler Q1-Q17 DR24 planet candidate catalog of Coughlin et al. (2016, Cat. J/ApJS/224/12)
- ID:
- ivo://CDS.VizieR/J/ApJ/738/170
- Title:
- False positive Kepler planet candidates
- Short Name:
- J/ApJ/738/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a framework to conservatively estimate the probability that any particular planet-like transit signal observed by the Kepler mission is in fact a planet, prior to any ground-based follow-up efforts. We use Monte Carlo methods based on stellar population synthesis and Galactic structure models, and report false positive probabilities (FPPs) for every Kepler Object of Interest, assuming a 20% intrinsic occurrence rate of close-in planets in the radius range 0.5R_{earth}_<R_p_<20R_{earth}_. Nearly 90% of the 1235 candidates have FPP<10%, and over half have FPP<5%. This probability varies with the magnitude and Galactic latitude of the target star, and with the depth of the transit signal - deeper signals generally have higher FPPs than shallower signals. We establish that a single deep high-resolution image will be an effective follow-up tool for the shallowest (Earth-sized) transits, providing the quickest route toward probabilistically validating the smallest candidates by potentially decreasing the FPP of an Earth-sized transit around a faint star from >10% to <1%. Since Kepler has detected many more planetary signals than can be positively confirmed with ground-based follow-up efforts in the near term, these calculations will be crucial to using the ensemble of Kepler data to determine population characteristics of planetary systems. We also describe how our analysis complements the Kepler team's more detailed BLENDER false positive analysis for planet validation.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/86
- Title:
- False positive probabilities for Q1-Q17 DR24 KOIs
- Short Name:
- J/ApJ/822/86
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present astrophysical false positive probability calculations for every Kepler Object of Interest (KOI) --the first large-scale demonstration of a fully automated transiting planet validation procedure. Out of 7056 KOIs, we determine that 1935 have probabilities vespa (Morton T.D. 2015ascl.soft03011M), a publicly available Python package that is able to be easily applied to any transiting exoplanet candidate.
- ID:
- ivo://CDS.VizieR/J/MNRAS/360/1345
- Title:
- F- and G-type stars in solar neighbourhood
- Short Name:
- J/MNRAS/360/1345
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new metallicity distribution and an age-metallicity relation are presented for 437 nearby F and G turn-off and sub-giant stars selected from radial velocity data of Nidever et al. (2002, Cat. J/ApJS/141/503). Photometric metallicities are derived from uvby-H{beta} photometry, and the stellar ages from the isochrones of Bergbusch & VandenBerg (2001ApJ...556..322B) as transformed to uvby photometry using the methods of Clem et al. (2004, Cat. J/AJ/127/1227).