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Start Over Subject ap stars Content Level Research
1. ACV variables in the Zwicky Transient Facility
ID:
ivo://CDS.VizieR/J/A+A/656/A125
Title:
ACV variables in the Zwicky Transient Facility
Short Name:
J/A+A/656/A125
Date:
16 Mar 2022 00:55:18
Publisher:
CDS
Description:
The present work presents a case study of known variables from the Zwicky Transient Facility (ZTF) survey, with the aim of investigating the survey's suitability for the detection and study of new ACV variables. Using suitable selection criteria based on the known characteristics of ACV variables, candidate ACV stars were selected from the ZTF Catalog of Periodic Variable Stars. All light curves were inspected in detail to select the most promising candidates. Where available, low-resolution spectra from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) were employed to classify the stars on the MK system and confirm their status as mCP stars. We have identified 86 new promising ACV star candidates. 15 of these stars have LAMOST spectra available, which, in all cases, confirm them as classical mCP stars, which highlights the viability of our approach. We present astrophysical parameters for all sample stars, which can be sorted into four subgroups characterized by distinct light curve shapes. Anti-phase variations in different photometric passbands, in particular, is a unique characteristic of a subset of ACV stars readily usable for their identification. The availability of data in three different passbands (g, r, and i) is a major advantage of the ZTF survey. On the basis of our experience with other photometric surveys and the analysis of light curves, we conclude that the ZTF is well suited for the search for, and the analysis of, ACV variables, which, however, are not considered in the available ZTF variable star catalogues. Further work will be concerned with the development and refinement of a search algorithm to correctly identify these stars in ZTF data and, subsequently, in massive photometric time-series databases in general.
2. Ap stars periodicity
ID:
ivo://CDS.VizieR/J/A+AS/121/57
Title:
Ap stars periodicity
Short Name:
J/A+AS/121/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
New data on the periods of Ap stars with references are presented (Table 1). 21 further stars are introduced for which a periodic variability has recently been discovered or for which it was known before but it was not reported in previous issues of this catalogue. For many stars also present in previous issues of the catalogue new determinations of the periods are given. Recently attributed variable star names are also quoted. Note: this catalog is included in <III/199>
3. Ap stars periodicity
ID:
ivo://CDS.VizieR/J/A+A/378/113
Title:
Ap stars periodicity
Short Name:
J/A+A/378/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
New data on the periods of Ap stars with references are presented. 161 further stars are introduced for which a periodic variability has recently been discovered or it was known before but it was not reported in previous issues of this catalogue. For many stars also present in previous issues of the catalogue new determinations of the periods are given. Recently attributed variable star names are also quoted.
4. Bp-Ap stars HR-diagram from Hipparcos data
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
5. Catalogue and Bibliography of Mn-Hg Stars
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.
6. CP stars magnetic fields catalog (2009)
ID:
ivo://CDS.VizieR/J/other/AstBu/71.302
Title:
CP stars magnetic fields catalog (2009)
Short Name:
J/other/AstBu/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of measuring longitudinal magnetic fields (B_e), rotation velocities (v_e_sini), and radial velocities (V_r_) of 44 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2009. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results. In this work we comment on the results for each of the stars.
7. CP stars magnetic fields catalog (2007)
ID:
ivo://CDS.VizieR/J/other/AstBu/69.427
Title:
CP stars magnetic fields catalog (2007)
Short Name:
J/other/AstBu/69
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog presents the results of magnetic field measurements for 39 chemically peculiar and 3 normal main sequence stars used as standard stars. Observations were carried out with the Main Stellar Spectrograph of the Russian 6-m telescope during 2007. The accuracy analysis for the longitudinal magnetic field measurements of the stars confirms that the systematic errors do not exceed 10-20G and are within the quoted limits. The absence of significant instrumental deviations follows from the measurements of theBD CP stars with well-known B_e_ variation curves.
8. CP stars magnetic fields catalog (2010)
ID:
ivo://CDS.VizieR/J/other/AstBu/72.391
Title:
CP stars magnetic fields catalog (2010)
Short Name:
J/other/AstBu/72
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of measuring longitudinal magnetic fields (B_e_), rotation velocities (v_esini_), and radial velocities (V_r_) of 92 stars observed with the Main Stellar Spectrograph (MSS) of the 6-m BTA telescope of the Special Astrophysical Observatory in 2010. Observations of standard stars without magnetic fields confirm the absence of systematic errors capable of introducing distortions into the longitudinal-field measurement results.
9. CP stars magnetic fields catalog (2008)
ID:
ivo://CDS.VizieR/J/other/AstBu/70.444
Title:
CP stars magnetic fields catalog (2008)
Short Name:
J/other/AstBu/70
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the magnetic field measurements of 37 chemically peculiar and 4 normal main sequence stars using circularly polarized spectra obtained in 2008 with a Zeeman analyzer on the Main Stellar Spectrograph (MSS) of the Russian 6-m telescope (BTA). Four new magnetic stars have been discovered (HD25999, HD35100, HD96237, and HD279021), the presence of a field was suspected in two stars (HD2887 and BD-12 2366), 16 previously known CP stars were continued to be monitored to study their fields. The results of the longitudinal magnetic field B_e_ measurements show that in stars with narrow spectral lines, systematic errors in B_e_ determination do not exceed 10-20G, which is within the statistical error. Our study of stars with reliable phase curves of the longitudinal field B_e_ show that there are no instrumental effects which can distort the observations.
10. Differential Stromgren photometry of 15 And
ID:
ivo://CDS.VizieR/J/A+A/480/187
Title:
Differential Stromgren photometry of 15 And
Short Name:
J/A+A/480/187
Date:
21 Oct 2021
Publisher:
CDS
Description:
The {lambda} Bootis stars are a chemically peculiar subgroup of main sequence A/F stars. Several of these fall into the instability strip of the {delta} Scuti stars and the whole spectroscopic group shows a high incidence of pulsational variability. We investigated the pulsational behaviour of the {lambda} Bootis star 15 And (HD 221756) to determine as many intrinsic mode frequencies as possible for asteroseismic applications.