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- ID:
- ivo://CDS.VizieR/III/59
- Title:
- Catalogue and Bibliography of Mn-Hg Stars
- Short Name:
- III/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the present catalogue all Ap stars of the type Mn-Hg, Mn or Hg are summarized. Also, the stars which are suspected to be of this type are included. If in the literature two or more classifications of a star indicate the same type (or one with high dispersion) it is listed as of known type. If only doubtful or different classifications exist for a star, it is indicated as suspected.
- ID:
- ivo://CDS.VizieR/J/A+AS/113/51
- Title:
- Catalogue of associations IRAS and S stars
- Short Name:
- J/A+AS/113/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cross identifications between the General Catalogue of Galactic S Stars (GCGSS), the IRAS Point Source Catalogue (PSC), and the Guide Star Catalogue (GSC) are presented. The purpose of the present catalogue is i) to provide a clean sample of S stars with far-IR data, and ii) to provide accurate GSC positions for S stars, superseding those listed in the GCGSS. The IRAS colour-colour diagram and the galactic distribution of S stars associated with an IRAS source are presented. Several S stars having extended images in at least one IRAS band have also been identified.
- ID:
- ivo://CDS.VizieR/J/MNRAS/480/2953
- Title:
- Catalogue of CP stars (HgMn, ApBp, AmFm)
- Short Name:
- J/MNRAS/480/2953
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present a new catalogue of chemically peculiar (CP) stars obtained by compiling publications in which abundances of metals are provided. Our catalogue includes 428 stars for which the data were obtained through spectroscopic observations. Most of them (416) are AmFm, HgMn, and ApBp stars. We have used this compilation to proceed to a statistical overview of the abundance anomalies versus the physical parameters of the stars. Spearman's rank correlation test has been applied, and a significant number of correlations of abundance peculiarities with respect to effective temperature, surface gravity, and rotation velocity have been found. Four interesting cases are discussed in details: the Mn peculiarities in HgMn stars, the Ca correlation with respect to effective temperature in AmFm stars, the case of helium and iron in ApBp stars. Furthermore, we checked for ApBp stars using Anderson-Darling test whether the belonging to a multiple system is a determinant parameter or not for abundance peculiarities.
- ID:
- ivo://CDS.VizieR/J/A+A/407/631
- Title:
- Catalogue of stellar effective magnetic fields
- Short Name:
- J/A+A/407/631
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalogue of averaged quadratic effective magnetic fields <B_e_> for 596 main sequence and giant stars. The catalogue is derived from measurements of the stellar effective magnetic field strengths B_e_, which were compiled from the existing literature.
- ID:
- ivo://CDS.VizieR/J/A+A/371/L5
- Title:
- CCD {Delta}a-photometry of NGC 1866
- Short Name:
- J/A+A/371/L5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the detection of the first extragalactic, classical chemically peculiar (CP) stars more than 100 years after the discovery of this group. Using the tool of CCD {Delta}a-photometry, eight definite positive detections in the globular-like stellar cluster NGC 1866 and its surrounding in the Large Magellanic Cloud were made. More than 1950 objects within a radius of 9.5' of the cluster center down to 20.5 magnitude were observed in this three filter, narrow band photometric system. Averaging more than 70 individual frames for all three filters yielded a 3{sigma} detection limit of 0.015mag for stars with V=20mag. Furthermore we found three objects with significantly negative {Delta}a-values indicating either an Ae/shell or {lambda} Bootis nature. The overall percentage of chemically peculiar stars for NGC 1866 (1.5%) seems lower than for the majority of open clusters in our Milky Way whereas the incidence within the LMC field is decisively less (0.3%). For a description of the {Delta}a photometric system, see e.g. <GCPD/75>
- ID:
- ivo://CDS.VizieR/J/A+A/462/591
- Title:
- CCD {Delta}a-photometry of 8 open clusters
- Short Name:
- J/A+A/462/591
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We continue our survey of magnetic chemically peculiar (CP2) stars in galactic open clusters to shed more light on their origin and evolution. To study the group of CP2 stars, it is essential to find these objects in different galactic environments and at a wide range of evolutionary stages. The knowledge of open cluster ages and metallicities can help for finding a correlation between these parameters and the (non-)presence of peculiarities, which has to be taken into account in stellar evolution models. ************************************************************************** * * * Sorry, but the author(s) never supplied the tabular material * * announced in the paper * * * **************************************************************************
- ID:
- ivo://CDS.VizieR/J/A+A/454/171
- Title:
- CCD {Delta}a-photometry of 8 open clusters
- Short Name:
- J/A+A/454/171
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The detection of magnetic chemically peculiar (CP2) stars in open clusters of the Milky Way can be used to study the influence of different galactic environments on the (non-)presence of peculiarities, which has to be taken into account in stellar evolution models. Furthermore it is still unknown if the CP2 phenomenon evolves, i.e. does the strength of the peculiarity feature at 5200{AA} increase or decrease with age. Methods. We have observed eight young to intermediate age open clusters in the {Delta}a photometric system.
- ID:
- ivo://CDS.VizieR/J/A+A/443/157
- Title:
- CCD photometry in 6 open clusters
- Short Name:
- J/A+A/443/157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Within the sample of six young open clusters (NGC 1502, NGC 3105, Stock 16, NGC 6268, NGC 7235 and NGC 7510) we have investigated 1753 objects using the narrow band, three filter Delta a photometric system resulting in the detection of eleven bona-fide magnetic chemically peculiar (CP) stars and five Be or metal-weak stars. The results for the distant cluster NGC 3105 is most important because of the still unknown influence of the global metallicity gradient of the Milky Way. These findings confirms that CP stars are present in open clusters of very young ages (logt>=6.90) at galactocentric distances up to 11.4kpc. For all programme clusters the age, reddening and distance modulus were derived using the corresponding isochrones. Some additional variable stars within Stock 16 could be identified by comparing different photometric studies.
- ID:
- ivo://CDS.VizieR/J/ApJ/747/102
- Title:
- ^12^C/^13^C ratio for 18 galactic R CrB stars
- Short Name:
- J/ApJ/747/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observed spectra of R Coronae Borealis (RCB) and hydrogen-deficient carbon (HdC) stars are analyzed by synthesizing the C_2_ Swan bands (1, 0), (0, 0), and (0, 1) using our detailed line list and the Uppsala model atmospheres. The (0, 1) and (0, 0) C_2_ bands are used to derive the ^12^C abundance, and the (1, 0) ^12^C^13^C band to determine the ^12^C/^13^C ratios. The carbon abundance derived from the C_2_ Swan bands is about the same for the adopted models constructed with different carbon abundances over the range 8.5 (C/He=0.1%) to 10.5 (C/He=10%). Carbon abundances derived from C I lines are about a factor of four lower than the carbon abundance of the adopted model atmosphere over the same C/He interval, as reported by Asplund et al., who dubbed the mismatch between adopted and derived C abundance as the "carbon problem." In principle, the carbon abundances obtained from C_2_ Swan bands and that assumed for the model atmosphere can be equated for a particular choice of C/He that varies from star to star. Then, the carbon problem for C_2_ bands is eliminated. However, such C/He ratios are in general less than those of the extreme helium stars, the seemingly natural relatives to the RCB and HdC stars. A more likely solution to the C_2_ carbon problem may lie in a modification of the model atmosphere's temperature structure. The derived carbon abundances and the ^12^C/^13^C ratios are discussed in light of the double degenerate and the final flash scenarios.
