- ID:
- ivo://CDS.VizieR/J/A+A/336/953
- Title:
- Bp-Ap stars HR-diagram from Hipparcos data
- Short Name:
- J/A+A/336/953
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using Hipparcos (Cat. <I/239>) parallaxes and proper motions together with radial velocity data, the luminosity calibration and kinematics of Bp-Ap stars have been obtained. The used statistical method allows to treat inhomogeneous samples and to identify the different groups. Six types of Bp-Ap stars (He-rich, He-weak, Hg-Mn, Si, Si+ and SrCrEu) have been considered. In most of the samples, with the exception of the He-rich and He-weak stars, two groups have been separated. Individual distances and luminosities are given for the stars belonging to the main groups which contain the largest number of stars. The list of stars in the secondary groups is given
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/440/28
- Title:
- Brightest Cluster Galaxies velocities
- Short Name:
- J/ApJ/440/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the use of Brightest Cluster Galaxies (BCGs) as standard candles for measuring galaxy peculiar velocities on large scales. We have obtained precise large-format CCD surface photometry and redshifts for an all-sky, volume-limited (z<=0.05) sample of 119 BCG. We reinvestigate the Hoessel (1980ApJ...241..493H) relationship between the metric luminosity, L_m_, within the central 10h^-1^kpc of the BCGs and the logarithmic slope of the surface brightness profile, {alpha}. The L_m_-{alpha} relationship reduces the cosmic scatter in L_m_ from 0.327mag to 0.244mag, yielding a typical distance accuracy of 17% per BCG. Residuals about the L_m_-{alpha} relationship are independent of BCG luminosity, BCG B-R_c_ color, BCG location within the host cluster, and richness of the host cluster. The metric luminosity is independent of cluster richness even before correcting for its dependence on {alpha}, which provides further evidence for the unique nature of the BCG luminosity function. Indeed, the BCG luminosity function, both before and after application of the {alpha}-correction, is consistent with a single Gaussian distribution. Half the BCGs in the sample show some evidence of small color gradients as a function of radius within their central 50h^-1^kpc regions but with almost equal numbers becoming redder as becoming bluer. However, with the central 10h^-1^kpc the colors are remarkably constant, the mean B-R_c_ color is 1.51 with a dispersion of only 0.06mag. The narrow photometric and color distributions of the BCGs, the lack of "second-parameter" effects, as well as the unique rich cluster environment of BCGs, argue that BCGs are the most homogeneous distance indicators presently available for large-scale structure research.
- ID:
- ivo://CDS.VizieR/II/144
- Title:
- Brightest stars in the field of M31
- Short Name:
- II/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This Catalogue of 11438 stars in the field of M31 is based on a set of Tautenburg Schmidt plates in U, B, V and R taken by van den Bergh. The range of visual magnitudes of stars is 11.5 < V < 20.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/283
- Title:
- BR magnitude and redshift of A1300
- Short Name:
- J/A+AS/124/283
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of an optical follow-up of X-ray bright clusters of galaxies located between 0.15<=z<=0.31: B and R photometry as well as medium resolution spectroscopy of the galaxies. The cluster studied here - A1300 - is found to have a redshift of 0.3072 and a velocity dispersion of 1210km/s, based on 52 cluster members. Structures are observed in the galaxy number counts but the velocity histogram shows no significant departure from a Gaussian distribution.
- ID:
- ivo://CDS.VizieR/J/A+A/177/131
- Title:
- CaII and MgII excess flux density in cool stars
- Short Name:
- J/A+A/177/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The relation between the CaII H and K line-tore flux density and rotation period is studied for a sample of 313 cool stars of luminosity classes ranging from II-III to V, and compared to similar relations for MgII h and k and soft X-ray.
- ID:
- ivo://CDS.VizieR/J/PASP/111/335
- Title:
- CaII-M_v_ Correlation (Wilson-Bappu Effect)
- Short Name:
- J/PASP/111/335
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hipparcos parallaxes were used to derive absolute visual magnitudes of G, K, and M stars with Ca II emission line widths previously measured by O.C. Wilson. A linear relationship similar to the one derived originally by Wilson & Bappu and improved by Lutz & Kelker was found from M_v_=+7 to -2. For stars brighter than M_v_=-2 a substantial number of stars show Ca II emission lines that are broader than expected from the linear fit. Most of those stars are bright giants and supergiants of type G.
- ID:
- ivo://CDS.VizieR/J/A+A/476/73
- Title:
- Calibration of Cepheid Period/Luminosity relation
- Short Name:
- J/A+A/476/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The universality of the Cepheid period-luminosity (PL) relations has been under discussion since metallicity effects were assumed to play a role in the value of the intercept and, more recently, of the slope of these relations. The goal of the present study is to calibrate the Galactic PL relations in various photometric bands (from B to K) and to compare the results to the well-established PL relations in the LMC. We use a set of 59 calibrating stars, the distances of which are measured using five different distance indicators: Hubble Space Telescope and revised Hipparcos parallaxes, infrared surface brightness and interferometric Baade-Wesselink parallaxes, and classical Zero-Age-Main-Sequence-fitting parallaxes for Cepheids belonging to open clusters or OB stars associations. A detailed discussion of absorption corrections and projection factor to be used is given.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2190
- Title:
- Caltech Faint Galaxy Redshift Survey. XIV
- Short Name:
- J/AJ/120/2190
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Morphological classifications are reported for Hubble Space Telescope images of 241 galaxies in the Hubble Deep Field and its flanking fields with measured redshifts in the interval 0.25<z<1.2, drawn from a magnitude-limited redshift survey to R=24.0. The galaxies are divided into three groups with redshifts in the intervals 0.25-0.6, 0.6-0.8, and 0.8-1.2. R_606_ images from the first group and I814 images from the second and third groups are compared with B-band images of nearby galaxies. All classifications were therefore made at approximately the same rest wavelength. Selection biases are discussed.
- ID:
- ivo://CDS.VizieR/J/AJ/122/611
- Title:
- Caltech Faint Galaxy Redshift Survey. XV.
- Short Name:
- J/AJ/122/611
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To circumvent the spatial effects of resolution on galaxy classification, the images of 233 objects of known redshift in the Hubble Deep Field (HDF) and its flanking fields that have redshifts in the range 0.20<z<1.10 were degraded to the resolution that they would have had if they were all located at a redshift of z=1.00. As in Paper XIV (Cat. <J/AJ/120/2190>) of the present series, the effects of shifts in rest wavelength were mitigated by using R-band images for the classification of galaxies with 0.2<z<0.6 and I-band images for objects with redshifts 0.6<z<1.1. A special effort was made to search for bars in distant galaxies. The present data strongly confirm the previous conclusion that the Hubble tuning fork diagram only provides a satisfactory framework for the classification of galaxies with z<0.3. More distant disk galaxies are often difficult to shoehorn into the Hubble classification scheme. The paucity of barred spirals and grand-design spirals at large redshifts is confirmed. It is concluded that the morphology of disk galaxies observed at look-back times smaller than 3-4Gyr differs systematically from that of more distant galaxies viewed at look-back times of 4-8Gyr. The disks of late-type spirals at z>0.5 are seen to be more chaotic than those of their nearer counterparts. Furthermore, the spiral structure in distant early-type spirals appears to be less well developed than it is in nearby early galaxies.
- ID:
- ivo://CDS.VizieR/I/219
- Title:
- Cape AC Zone Data Reduced to ACRS
- Short Name:
- I/219
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Cape Zone, whose plates are centered between declinations -41 and -51 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 544,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
