- ID:
- ivo://CDS.VizieR/J/MNRAS/435/3444
- Title:
- ALHAMBRA survey morphological catalogue
- Short Name:
- J/MNRAS/435/3444
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Advanced Large Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) is photometric survey designed to trace the cosmic evolution and cosmic variance. It covers a large area of ~4deg^2^ in eight fields, where seven fields overlap with other surveys, allowing us to have complementary data in other wavelengths. All observations were carried out in 20 continuous, medium band (30nm width) optical and 3 near-infrared (JHK) bands, providing the precise measurements of photometric redshifts. In addition, morphological classification of galaxies is crucial for any kind of galaxy formation and cosmic evolution studies, providing the information about star formation histories, their environment and interactions, internal perturbations, etc. We present a morphological classification of >40000 galaxies in the ALHAMBRA survey. We associate to every galaxy a probability to be early type using the automated Bayesian code galsvm. Despite of the spatial resolution of the ALHAMBRA images (~1arcsec), for 22051 galaxies, we obtained the contamination by other type of less than 10 percent. Of those, 1640 and 10322 galaxies are classified as early- (down to redshifts ~0.5) and late-type (down to redshifts ~1.0), respectively, with magnitudes F_613W_<=22.0. In addition, for magnitude range 22.0<F_613W_<=23.0, we classified other 10089 late-type galaxies with redshifts <=1.3. We show that the classified objects populate the expected regions in the colour-mass and colour-magnitude planes. The presented data set is especially attractive given the homogeneous multiwavelength coverage available in the ALHAMBRA fields, and is intended to be used in a variety of scientific applications. The low-contamination catalogue (<10 percent) is made publicly available with this paper.
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- ID:
- ivo://CDS.VizieR/J/ApJ/836/77
- Title:
- A library of high-S/N optical spectra of FGKM stars
- Short Name:
- J/ApJ/836/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Classification of stars, by comparing their optical spectra to a few dozen spectral standards, has been a workhorse of observational astronomy for more than a century. Here, we extend this technique by compiling a library of optical spectra of 404 touchstone stars observed with Keck/HIRES by the California Planet Search. The spectra have high resolution (R~60000), high signal-to-noise ratio (S/N~150/pixel), and are registered onto a common wavelength scale. The library stars have properties derived from interferometry, asteroseismology, LTE spectral synthesis, and spectrophotometry. To address a lack of well-characterized late-K dwarfs in the literature, we measure stellar radii and temperatures for 23 nearby K dwarfs, using modeling of the spectral energy distribution and Gaia parallaxes. This library represents a uniform data set spanning the spectral types ~M5-F1 (T_eff_~3000-7000K, R_*_~0.1-16R_{Sun}_). We also present "Empirical SpecMatch" (SpecMatch-Emp), a tool for parameterizing unknown spectra by comparing them against our spectral library. For FGKM stars, SpecMatch-Emp achieves accuracies of 100K in effective temperature (T_eff_), 15% in stellar radius (R_*_), and 0.09dex in metallicity ([Fe/H]). Because the code relies on empirical spectra it performs particularly well for stars ~K4 and later, which are challenging to model with existing spectral synthesizers, reaching accuracies of 70K in T_eff_, 10% in R_*_, and 0.12dex in [Fe/H]. We also validate the performance of SpecMatch-Emp, finding it to be robust at lower spectral resolution and S/N, enabling the characterization of faint late-type stars. Both the library and stellar characterization code are publicly available.
- ID:
- ivo://CDS.VizieR/III/92
- Title:
- A Library of Stellar Spectra
- Short Name:
- III/92
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The machine-readable version of the library contains digital spectra of 161 stars of spectral types O through M and luminosity classes I, III, and V. Most stars are of solar metallicity, although two were chosen specifically for low metallicity. The data were obtained with the Intensified Reticon Scanner on the #1 91-cm telescope at Kitt Peak National Observatory. The scans cover the wavelength range 3510-7427 angstroms, with a resolution of approximately 4.5 angstroms, while the typical photometric uncertainty of each resolution element is about 1 percent and broadband variations are < 3 percent.
- ID:
- ivo://CDS.VizieR/J/MNRAS/380/162
- Title:
- Aligned radio polarizations of quasars
- Short Name:
- J/MNRAS/380/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the very large Jodrell Bank VLA Astrometric Survey/Cosmic Lens All-Sky Survey 8.4-GHz surveys of flat-spectrum radio sources to test the hypothesis that there is a systematic alignment of polarization position angle vectors on cosmological scales of the type claimed by Hutsemekers et al. (2005, Cat. <J/A+A/441/915>). The polarization position angles of 4290 sources with polarized flux density 1mJy have been examined. They do not reveal large-scale alignments either as a whole or when split in half into high-redshift (z>=1.24) and low-redshift subsamples. Nor do the radio sources which lie in the specific areas covered by Hutsemekers et al. (<J/A+A/441/915>) show any significant effect. We have also looked at the position angles of parsec-scale jets derived from very long baseline interferometry observations and again find no evidence for systematic alignments. Finally, we have investigated the correlation between the polarization position angle and those of the parsec-scale jets. As expected, we find that there is a tendency for the polarization angles to be perpendicular to the jet angles. However, the difference in jet and polarization position angles does not show any systematic trend in different parts of the sky.
- ID:
- ivo://CDS.VizieR/J/A+A/575/A48
- Title:
- Alignment of galaxies in galaxy clusters
- Short Name:
- J/A+A/575/A48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Torques acting on galaxies lead to physical alignments, but the resulting ellipticity correlations are difficult to predict. As they constitute a major contaminant for cosmic shear studies, it is important to constrain the intrinsic alignment signal observationally. We measured the alignments of satellite galaxies within 90 massive galaxy clusters in the redshift range 0.05<z<0.55 and quantified their impact on the cosmic shear signal. We combined a sample of 38104 galaxies with spectroscopic redshifts with high-quality data from the Canada-France-Hawaii Telescope. We used phase-space information to select 14576 cluster members, 14250 of which have shape measurements and measured three different types of alignment: the radial alignment of satellite galaxies toward the brightest cluster galaxies (BCGs), the common orientations of satellite galaxies and BCGs, and the radial alignments of satellites with each other. Residual systematic effects are much smaller than the statistical uncertainties. We detect no galaxy alignment of any kind out to at least 3r_200_. The signal is consistent with zero for both blue and red galaxies, bright and faint ones, and also for subsamples of clusters based on redshift, dynamical mass, and dynamical state. These conclusions are unchanged if we expand the sample with bright cluster members from the red sequence. We augment our constraints with those from the literature to estimate the importance of the intrinsic alignments of satellites compared to those of central galaxies, for which the alignments are described by the linear alignment model. Comparison of the alignment signals to the expected uncertainties of current surveys such as the Kilo-Degree Survey suggests that the linear alignment model is an adequate treatment of intrinsic alignments, but it is not clear whether this will be the case for larger surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/441/915
- Title:
- Alignments of quasar polarization vectors
- Short Name:
- J/A+A/441/915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on a new sample of 355 quasars with significant optical polarization and using complementary statistical methods, we confirm that quasar polarization vectors are not randomly oriented over the sky with a probability often in excess of 99.9%.
- ID:
- ivo://CDS.VizieR/J/AJ/161/231
- Title:
- A list of ~330000 stars Kepler missed
- Short Name:
- J/AJ/161/231
- Date:
- 09 Mar 2022 22:00:00
- Publisher:
- CDS
- Description:
- The Kepler Mission revolutionized exoplanet science and stellar astrophysics by obtaining highly precise photometry of over 200000 stars over 4yr. A critical piece of information to exploit Kepler data is its selection function, since all targets had to be selected from a sample of half a million stars on the Kepler CCDs using limited information. Here we use Gaia DR2 to reconstruct the Kepler selection function and explore possible biases with respect to evolutionary state, stellar multiplicity, and kinematics. We find that the Kepler target selection is nearly complete for stars brighter than Kp<14mag and was effective at selecting main-sequence stars, with the fraction of observed stars decreasing from 95% to 60% between 14<Kp<16mag. We find that the observed fraction for subgiant stars is only 10% lower, confirming that a significant number of subgiants selected for observation were believed to be main-sequence stars. Conversely we find a strong selection bias against low-luminosity red giant stars (R~3-5R_{sun}_, Teff~5500K), dropping from 90% at Kp=14mag to below 30% at Kp=16mag, confirming that the target selection was efficient at distinguishing dwarfs from giants. We compare the Gaia Re-normalized Unit Weight Error (RUWE) values of the observed and nonobserved main-sequence stars and find a difference in elevated (>1.2) RUWE values at ~{sigma} significance, suggesting that the Kepler target selection shows some bias against either close or wide binaries. We furthermore use the Gaia proper motions to show that the Kepler selection function was unbiased with respect to kinematics.
- ID:
- ivo://CDS.VizieR/V/17A
- Title:
- A list of Supergiant Stars
- Short Name:
- V/17A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue is a compilation of about 5000 stars classified as supergiants (class I or II) in the literature. The following information is given: DM and HD identifications, coordinates, photometry, radial velocity and MK classification
- ID:
- ivo://CDS.VizieR/J/AcA/50/177
- Title:
- All Sky Automated Survey Catalog
- Short Name:
- J/AcA/50/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of the first two years of observations using the All Sky Automated Survey prototype camera are presented. More than 140000 stars in 50 Selected Fields covering 300 square degrees were monitored each clear night in the I-band resulting in the ASAS Photometric I-band Catalog containing over 5*10^7^ individual measurements. Nightly monitoring of over 100 standard stars confirms that most of our data remains within {sigma}_I_=0.03mag of the standard I system. Search for the stars varying on the time scales longer than a day revealed about 3800 variable stars (mostly irregular, pulsating and binaries) brighter than 13mag. Only 630 of them are known or suspected variables included in the GCVS (Kholopov 1985, Cat. <II/214>). Among the stars brighter than I~7.5 (which are saturated on our frames) we have found about 50 variables (12 are in the GCVS, 6 others in the Hipparcos catalog (Cat. <I/239>). Because of the large volume of data we present here only selected tables and light curves, but the complete ASAS Catalog of Variable Stars (currently divided into Periodic and Miscellaneous sections) and all photometric data are available on the Internet http://www.astrouw.edu.pl/~gp/asas/asas.html or http://archive.princeton.edu/~asas/
- ID:
- ivo://CDS.VizieR/J/AcA/48/35
- Title:
- All Sky Automated Survey variable stars
- Short Name:
- J/AcA/48/35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of the first two months of observations using the All Sky Survey prototype camera are presented. More than 45000 stars in 24 Selected Fields covering 140 square degrees were monitored a few times per night resulting in the I-band catalog containing 10^7^ individual measurements. Period search revealed 126 variable stars brighter than 13mag with periods less than 20d. Only 30 of them are known variable stars included in the General Catalogue of Variable Stars (<II/214>). The other 90 objects are newly detected variable stars - mainly eclipsing binaries (75%) and pulsating stars (17%). We estimate that completeness of the current catalogs of variable stars is smaller than 50% already for the stars brighter than 9mag. The catalog is accessible over the WWW: http://www.astrouw.edu.pl/~gp/asas/asas.html
