- ID:
- ivo://CDS.VizieR/J/ApJ/571/512
- Title:
- Distances of white dwarf stars
- Short Name:
- J/ApJ/571/512
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The most recent version of the Catalog of Spectroscopically Identified White Dwarfs lists 2249 white dwarf stars. Among these stars are 109 white dwarfs that have either reliable trigonometric parallaxes or color-based distance moduli that place them at a distance within 20pc of the Sun. Most of these nearby white dwarfs are isolated stars, but 28 (25% of the sample) are in binary systems, including such well-known systems as Sirius A/B and Procyon A/B. There are also three double degenerate systems in this sample of the local white dwarf population. The sample of local white dwarfs is largely complete out to 13pc, and the local density of white dwarf stars is found to be 5.0+/-0.7x10^-3^pc^-3^, with a corresponding mass density of 3.4+/-0.5x10^-3^M{sun}_/pc^3^
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/80/972
- Title:
- Dwarf K and M stars at low latitudes
- Short Name:
- J/AJ/80/972
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 100 dwarf K and M stars found on objective-prism plates taken at low galactic latitudes, mostly in the southern sky. Most stars were recognized from the strength of the sodium D lines, and the majority have known proper motions of 0.1" or more per annum. Ninety-nine of these stars lack previous spectral classification; one lacks previous observation of line emission. Most have below the limits of the DM charts, and for there we provide identification charts.
- ID:
- ivo://CDS.VizieR/J/AJ/158/106
- Title:
- Eclipsing binaries RVs from APOGEE spectra
- Short Name:
- J/AJ/158/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic eclipsing binaries (SEBs) are fundamental benchmarks in stellar astrophysics and today are observed in breathtaking detail by missions like the Transiting Exoplanet Survey Satellite (TESS), Kepler, and Apache Point Observatory Galactic Evolution Experiment (APOGEE). We develop a methodology for simultaneous analysis of high-precision Kepler light curves and high-resolution near-infrared spectra from APOGEE and present orbital solutions and evolutionary histories for a subset of SEBs within this overlap. Radial velocities extracted from APOGEE spectra using the broadening function (BF) technique are combined with Kepler light curves and to yield binary orbital solutions. The BF approach yields more precise radial velocities than the standard cross-correlation function, which in turn yields more precise orbital parameters and enables the identification of tertiary stars. The orbital periods of these seven SEBs range from 4 to 40 days. Four of the systems (KIC 5285607, KIC 6864859, KIC 6778289, and KIC 4285087) are well-detached binaries. The remaining three systems have apparent tertiary companions, but each exhibit two eclipses along with at least one spectroscopically varying component (KIC 6449358, KIC 6131659, and KIC 6781535). Gaia distances are available for four targets which we use to estimate temperatures of both members of these SEBs. We explore evolutionary histories in H-R diagram space and estimate ages for this subset of our sample. Finally, we consider the implications for the formation pathways of close binary systems via interactions with tertiary companions. Our methodology combined with the era of big data and observation overlap opens up the possibility of discovering and analyzing large numbers of diverse SEBs, including those with high flux ratios and those in triple systems.
- ID:
- ivo://CDS.VizieR/J/ApJS/248/33
- Title:
- Edge-on HI-rich LSB galaxies from ALFALFA
- Short Name:
- J/ApJS/248/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low surface brightness galaxies (LSBGs) are defined as galaxies that are fainter than dark night sky and are important for studying our universe. Particularly, edge-on galaxies are useful for the study of rotational velocity and dynamical properties of galaxies. Hence here we focus on searching for edge-on LSBGs. In order to find these edge-on dim galaxies, a series of effects caused by inclination, including the surface brightness profile, internal extinction, and scale length, have been corrected. In this work, we present a catalog of 281 edge-on LSBG candidates, which are selected from the crossmatch between Sloan Digital Sky Survey Data Release 7 and the 40% ALFALFA catalog. We also present the properties of these edge-on LSBG candidates including the absolute magnitude, central surface brightness, B-V color, scale length, and relative thickness. Our result suggests that the correction of inclination effects is very important for obtaining a complete sample of LSBGs.
- ID:
- ivo://CDS.VizieR/J/A+A/369/178
- Title:
- Effective temperatures of carbon-rich stars
- Short Name:
- J/A+A/369/178
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 10 is the full version of Table A1 given in Appendix. There are 441 entries corresponding to 441 spectral energy distributions (SEDs) of 406 carbon stars and related objects studied in Papers I (<J/A+A/321/236>, II (<J/A+A/342/773> and III (<J/A+A/344/263>) (photometric group G in column 3 and extinction A(J) at J-filter in column 4). Two estimates of the effective temperature (Sect. 12) from the SED (calibrated color indices) and bolometric flux (integrated flux: 0.36 to 100{mu}m) are given in columns 5 and 6 respectively, together with the adopted mean value in column 7. Also given in column 8, the apparent bolometric magnitude of the SED/Star, and in column 9 as "remarks", the variation phase information whenever available, the detection of circumstellar extinction and/or emission with associated mbol2 in a few case (see Sect. 13).
- ID:
- ivo://CDS.VizieR/J/ApJS/111/163
- Title:
- Einstein X-ray survey of galaxies. I.
- Short Name:
- J/ApJS/111/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a complete Einstein imaging proportional counter X-ray survey of optically-selected galaxies from the Shapley-Ames Catalog (Cat. <VII/112>), the Uppsala General Catalog (Cat. <VII/26>) and the European Southern Observatory Catalog (Cat. <VII/115>). Well-defined optical criteria are used to select the galaxies, and X-ray fluxes are measured at the optically-defined positions. The result is a comprehensive list of X-ray detection and upper limit measurements for 1018 galaxies. Of these, 827 have either independent distance estimates or radial velocities. Associated optical, redshift, and distance data have been assembled for these galaxies, and their distances come from a combination of directly predicted distances and those predicted from the Faber-Burstein Great Attractor/Virgocentric infall model. The accuracy of the X-ray fluxes has been checked in three different ways; all are consistent with the derived X-ray fluxes being of <=0.1 dex accuracy. In particular, there is agreement with previously published X-ray fluxes for galaxies in common with a 1991 study by Roberts et al. (1991ApJS...75..751R) and a 1992 study by Fabbiano et al. (1992ApJS...80..531F).The data presented here will be used in further studies to characterize the X-ray output of galaxies of various morphological types and thus to enable the determination of the major sources contributing to the X-ray emission from galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/804/109
- Title:
- Equivalent widths of RGB stars in NGC 5053
- Short Name:
- J/ApJ/804/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 5053 provides a rich environment to test our understanding of the complex evolution of globular clusters (GCs). Recent studies have found that this cluster has interesting morphological features beyond the typical spherical distribution of GCs, suggesting that external tidal effects have played an important role in its evolution and current properties. Additionally, simulations have shown that NGC 5053 could be a likely candidate to belong to the Sagittarius dwarf galaxy (Sgr dSph) stream. Using the Wisconsin-Indiana-Yale-NOAO-Hydra multi-object spectrograph, we have collected high quality (signal-to-noise ratio ~75-90), medium-resolution spectra for red giant branch stars in NGC 5053. Using these spectra we have measured the Fe, Ca, Ti, Ni, Ba, Na, and O abundances in the cluster. We measure an average cluster [Fe/H] abundance of -2.45 with a standard deviation of 0.04 dex, making NGC 5053 one of the most metal-poor GCs in the Milky Way (MW). The [Ca/Fe], [Ti/Fe], and [Ba/Fe] we measure are consistent with the abundances of MW halo stars at a similar metallicity, with alpha-enhanced ratios and slightly depleted [Ba/Fe]. The Na and O abundances show the Na-O anti-correlation found in most GCs. From our abundance analysis it appears that NGC 5053 is at least chemically similar to other GCs found in the MW. This does not, however, rule out NGC 5053 being associated with the Sgr dSph stream.
108. EUVE optical atlas
- ID:
- ivo://CDS.VizieR/J/PASP/109/998
- Title:
- EUVE optical atlas
- Short Name:
- J/PASP/109/998
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Extreme Ultraviolet Explorer (EUVE) has been detecting EUV sources since its launch in June 1992. Positions of 540 sources have been made available to the community by the EUVE team. We have extracted 7'x7' images centered on these 540 EUVE sources from the Space Telescope Science Institute digitized sky archives. We present these images as mosaic finder charts to aid observers trying to identify EUVE sources, or to characterize known sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/275/1102
- Title:
- Evolution of quasar luminosity function
- Short Name:
- J/MNRAS/275/1102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In an earlier paper (Hawkins & Veron, 1993MNRAS.260..202H) we presented quasar luminosity functions in three redshift bins, derived from a variability selected sample. Here we provide a major extension to this survey, with a view to improving statistics and completeness, and extending the redshift range. The luminosity functions for redshifts of less than 2.2 show a featureless power law of the form {phi}=10^{beta}(M-M_0_)^, with no sign of a 'break'. The quasar luminosity function is also derived by the redshift range 2.2<z<3.2, which again shows a featureless power law, but with a steeper slope. When the data are combined with a new sample of bright quasars, the quasar luminosity functions in all four redshift ranges are consistent with a single power law of index {beta}=0.63. Plots of quasar space density as a function of redshift in three luminosity bins are also presented and show strong evolution at low redshift but nearly constant space density beyond a redshift of 2.
- ID:
- ivo://CDS.VizieR/J/ApJ/679/156
- Title:
- Extra central light in galactic nuclei. I.
- Short Name:
- J/ApJ/679/156
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the origin and properties of "extra" or "excess" central light in the surface brightness profiles of remnants of gas-rich mergers. By combining a large set of hydrodynamical simulations with data on observed mergers that span a broad range of profiles at various masses and degrees of relaxation, we show how to robustly separate the physically meaningful extra light (i.e., the stellar population formed in a compact central starburst during a gas-rich merger) from the outer profile established by violent relaxation acting on stars already present in the progenitor galaxies prior to the final stages of the merger. This separation is sensitive to the treatment of the profile, and we demonstrate that certain fitting procedures can yield physically misleading results. We show that our method reliably recovers the younger starburst population, and examine how the properties and mass of this component scale with the mass, gas content, and other aspects of the progenitors. We consider the time evolution of the profiles in different bands, and estimate the biases introduced by observational studies at different phases and wavelengths. We show that, when appropriately quantified, extra light is ubiquitous in both observed and simulated gas-rich merger remnants, with sufficient mass (~3%-30% of the stellar mass) to explain the apparent discrepancy in the maximum phase-space densities of ellipticals and their progenitor spirals.
