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- ID:
- ivo://CDS.VizieR/J/A+A/372/879
- Title:
- JKBV photometry of NGC 2141
- Short Name:
- J/A+A/372/879
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report CCD optical (B and V passbands) and near IR (J and K bands) observations in the region of the old open cluster NGC 2141. By combining the two sets of photometry (500 stars in common) we derive new estimates of the cluster's fundamental parameters. We confirm that the cluster is 2.5Gyrs old, but, with respect to previous investigations, we obtain a slightly larger reddening (E(B-V)=0.40), and a slightly shorter distance (3.8kpc) from the Sun. Finally, we present the Luminosity Function (LF) in the V band, which is another age indicator. We provide a good fit for the age range inferred from isochrones by assuming the Kroupa et al. (1993MNRAS.262..545K) IMF up to M_V_=5.0. We interpret the disagreement at fainter magnitudes as evidence of mass segregation.
- ID:
- ivo://CDS.VizieR/II/300
- Title:
- JMMC Stellar Diameters Catalogue - JSDC
- Short Name:
- II/300
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains stellar angular diameter estimate for bright stars, complete for all stars with Hipparcos parallaxes. The JMMC Calibrator Workgroup has long developed methods to estimate the angular diameter of stars, and provides this expertise in the SearchCal software (http://www.jmmc.fr/searchcal). "SearchCal" creates a dynamical catalogue of stars suitable to calibrate Optical Long-Baseline Interferometry (OLBI) observations from on-line queries of CDS catalogues, according to observational parameters. In essence, SearchCal is limited only by the completeness of the stellar catalogues it uses, and in particular is not limited in magnitude. SearchCal being an application centered on OLBI peculiar purposes, it appeared useful to publish the estimated angular diameters of all stars with known parallaxes in a static catalogue. The present catalogue of stellar angular diameters has been obtained from an automated SearchCal results aggregation on the whole celestial sphere. For each star, the value of the limb-darkened angular diameters are computed using a surface brightness method and calibrations for (B-V), (V-R) and (V-K) color indexes. Stars whose angular diameters estimated from the various color indexes are not comparable, are rejected, and a reliable error on the estimated diameter is computed (1). For details of the method see Bonneau et al. (2006A&A...456..789B). To avoid specific confusion problems, spectroscopic binaries in the 9th Catalogue of Spectroscopic Binary Orbits (Pourbaix et al., 2009, Cat. B/sb9) or close visual binaries with a separation of less than 2 arc seconds in the Washington Visual Double Star Catalog (Mason et al., 2001, Cat. B/wds) have been filtered out.
- ID:
- ivo://CDS.VizieR/II/346
- Title:
- JMMC Stellar Diameters Catalogue - JSDC. Version 2
- Short Name:
- II/346
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains stellar angular diameter estimates for nearly all the stars of the Hipparcos and Tycho catalogue that have an associated spectral type in Simbad/CDS. The median error on the diameters is around 1.5%, with possible biases of around ~2%. For each object, the limb-darkened diameter retained is the mean value of several estimates performed using different couples of photometries. The chi-square representing the dispersion between these values is also given (it is below 2 for ~400000 stars). An additional flag signals stars that could represent a risk if chosen as calibrators for Optical Long-Baseline Interferometry, independently of the correctness of their apparent diameter estimate. This catalog replaces the catalog II/300/jsdc .
- ID:
- ivo://CDS.VizieR/J/A+A/394/97
- Title:
- Johnson and Stromgren photometry of V784 Cas
- Short Name:
- J/A+A/394/97
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new Johnson and Stromgren photometric observations of the delta Scuti type variable star V784 Cassiopeae. The data were obtained in three consecutive years between 1999 and 2001. The bulk of the measurements was made at the Sierra Nevada Observatory (Spain) with the 0.9m telescope equipped with a four-channel spectrograph photometer. UBV data were taken with the 0.4m telescope of Szeged Observatory (Hungary).
1776. K and M stars photometry
- ID:
- ivo://CDS.VizieR/J/AJ/105/1962
- Title:
- K and M stars photometry
- Short Name:
- J/AJ/105/1962
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Broadband UBVRI photometry is presented for 687 stars from among the dwarf K and M stars found spectroscopically by Vyssotsky [1958AJ.....63..211V]. Of these, 211 are without previous photometry.
1777. Kappa Dra
- ID:
- ivo://CDS.VizieR/J/A+AS/107/403
- Title:
- Kappa Dra
- Short Name:
- J/A+AS/107/403
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJS/237/14
- Title:
- KASI-Yonsei Deep Imaging Survey of Clusters (KYDISC)
- Short Name:
- J/ApJS/237/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the KASI-Yonsei Deep Imaging Survey of Clusters targeting 14 clusters at 0.015<~z<~0.144 using the Inamori Magellan Areal Camera and Spectrograph on the 6.5m Magellan Baade telescope and the MegaCam on the 3.6m Canada-France-Hawaii Telescope. We provide a catalog of cluster galaxies that lists magnitudes, redshifts, morphologies, bulge-to-total ratios, and local density. Based on the 1409 spectroscopically confirmed cluster galaxies brighter than -19.8 in the r band, we study galaxy morphology, color, and visual features generated by galaxy mergers. We see a clear trend between morphological content and cluster velocity dispersion, which was not presented by previous studies using local clusters. Passive spirals are preferentially found in a highly dense region (i.e., cluster center), indicating that they have gone through environmental quenching. In deep images ({mu}_r'_~27mag/arcsec^2^), 20% of our sample shows signatures of recent mergers, which is not expected from theoretical predictions and a low frequency of ongoing mergers in our sample (~4%). Such a high fraction of recent mergers in the cluster environment supports a scenario that the merger events that made the features have preceded the galaxy accretion into the cluster environment. We conclude that mergers affect a cluster population mainly through the preprocessing of recently accreted galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/860/109
- Title:
- Keck HIRES obs. of 245 subgiants (retired A stars)
- Short Name:
- J/ApJ/860/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Exoplanet surveys of evolved stars have provided increasing evidence that the formation of giant planets depends not only on stellar metallicity ([Fe/H]) but also on the mass (M*). However, measuring accurate masses for subgiants and giants is far more challenging than it is for their main-sequence counterparts, which has led to recent concerns regarding the veracity of the correlation between stellar mass and planet occurrence. In order to address these concerns, we use HIRES spectra to perform a spectroscopic analysis on a sample of 245 subgiants and derive new atmospheric and physical parameters. We also calculate the space velocities of this sample in a homogeneous manner for the first time. When reddening corrections are considered in the calculations of stellar masses and a -0.12M_{sun}_ offset is applied to the results, the masses of the subgiants are consistent with their space velocity distributions, contrary to claims in the literature. Similarly, our measurements of their rotational velocities provide additional confirmation that the masses of subgiants with M*>=1.6M_{sun}_ (the "retired A stars") have not been overestimated in previous analyses. Using these new results for our sample of evolved stars, together with an updated sample of FGKM dwarfs, we confirm that giant planet occurrence increases with both stellar mass and metallicity up to 2.0M_{sun}_. We show that the probability of formation of a giant planet is approximately a one-to-one function of the total amount of metals in the protoplanetary disk M* 10^[Fe/H]. This correlation provides additional support for the core accretion mechanism of planet formation.
- ID:
- ivo://CDS.VizieR/J/ApJ/869/123
- Title:
- Keck Lyman continuum spectroscopic survey (KLCS)
- Short Name:
- J/ApJ/869/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a deep spectroscopic survey quantifying the statistics of the escape of ionizing radiation from star-forming galaxies at z~3. We measure the ratio of ionizing to non-ionizing UV flux density <f_900_/f_1500_>_obs_, where f_900_ is the mean flux density evaluated over the range [880,910]{AA}. We quantify the emergent ratio of ionizing to non-ionizing UV flux density by analyzing high signal-to-noise ratio composite spectra formed from subsamples with common observed properties and numbers sufficient to reduce the statistical uncertainty in the modeled IGM+CGM correction to obtain precise values of <f_900_/f_1500_>_out_, including a full-sample average <f_900_/f_1500>_out_=0.057{+/-}0.006. We show that <f_900_/f_1500_>_out_ increases monotonically with W_{lambda}_(Ly{alpha}), inducing an inverse correlation with UV luminosity as a by-product. We fit the composite spectra using stellar spectral synthesis together with models of the ISM in which a fraction f_c_ of the stellar continuum is covered by gas with column density N_HI_. We show that the composite spectra simultaneously constrain the intrinsic properties of the stars (L_900_/L_1500_)_int_ along with f_c_, N_HI_, E(B-V), and f_esc,abs_, the absolute escape fraction of ionizing photons. We find a sample-averaged f_esc,abs_=0.09{+/-}0.01, with subsamples falling along a linear relation <f_esc,abs_>~0.75[W_{lambda}_(Ly{alpha})/110{AA}]. Using the far-UV luminosity function, the distribution function n(W(Ly{alpha})), and the relationship between W_{lambda}_(Ly{alpha}) and <f_900_/f_1500_>_out_, we estimate the total ionizing emissivity of z~3 star-forming galaxies with M_uv_<=-19.5, which exceeds the contribution of quasi-stellar objects by a factor of ~3, and accounts for ~50% of the total {epsilon}LyC at z~3 estimated using indirect methods.
