- 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.
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- 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.
- ID:
- ivo://CDS.VizieR/J/MNRAS/431/2106
- Title:
- CU Vir Stroemgren differential photometry
- Short Name:
- J/MNRAS/431/2106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In order to measure the variations of the magnetic chemically peculiar star CU Vir, we obtained 2821 good Stroemgren uvby photometric values from the Four College Automated Photometric Telescope in the period 1998-2012 and 5529 values from the Solar Mass Ejection Imager in the period 2003-2006, allowing us to further clarify the situation concerning its rotational period, described previously by Pyper et al. (1998A&A...339..822P). Our main result is that the O-C data since 1993 are consistent with a constant period of 0.5207137+/-0.0000010d, which is longer than the period 0.52070308d of Pyper et al. (1998A&A...339..822P). The data during the time period 1993-2012 show no evidence of glitches. The data between 1987 and 1993 correspond to a shorter period of 0.520701d, and the inclusion of those data in the previous study made the published period come out shorter. We also cannot rule out a constantly lengthening period if the data since 1987 are included; however, the fit is slightly better for a constant period. At least five more years of consistent data will be required to distinguish between these two models. Radio astronomy data published since 1998 show phase shifts in the radio emission peaks that are inconsistent with the rotation period inferred from the optical photometry. These shifts may be due to instabilities in the region where the radio emissions originate; they indicate that the photosphere and the upper atmosphere are not rigidly coupled.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A42
- Title:
- {Delta}a-photometry in 10 open clusters
- Short Name:
- J/A+A/564/A42
- 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 ten young to intermediate age open clusters in the {Delta}a photometric system.
- ID:
- ivo://CDS.VizieR/J/A+A/441/631
- Title:
- {Delta}a photometry of CP stars
- Short Name:
- J/A+A/441/631
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have summarized all {Delta}a measurements for galactic field stars (1474 objects) from the literature published over more than two decades. These measurements were, for the first time, compiled and homogeneously analyzed. The {Delta}a intermediate band photometric system samples the depth of the 5200{AA} flux depression by comparing the flux at the center with the adjacent regions with bandwidths of 110{AA} to 230{AA}. Because it was slightly modified over the last three decades, we checked for systematic trends for the different measurements but found no correlations whatsoever. The {Delta}a photometric system is most suitable to detecting magnetic chemically peculiar (CP) stars with high efficiency, but is also capable of detecting a small percentage of non-magnetic CP objects. Furthermore, the groups of (metal-weak) lambda Bootis, as well as classical Be/shell stars, can be successfully investigated. In addition, we also analyzed the behaviour of supergiants (luminosity class I and II). On the basis of apparent normal type objects, the correlation of the 3sigma significance limit and the percentage of positive detection for all groups was derived.
- ID:
- ivo://CDS.VizieR/J/A+AS/130/455
- Title:
- Delta-a photometry of southern B & A bright stars
- Short Name:
- J/A+AS/130/455
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 2 lists the HR and HD numbers, the run in which the observations were obtained (sometimes several observations per run and/or on several runs, a, Delta a absolute and expressed in units of the average standard deviation of normal stars from the normality line, b-y and its dereddened quantity (b-y)_0, m_1, the spectral types from the BS Catalogue and the Michigan spectral survey (where available), then a column which indicates whether the object was used for the construction of the normality line (N) or entered the group of double stars (D), and finally the peculiarity group to which the star belongs (Preston's CP1-4, {lambda} Boo, {delta} Del, emission line objects E, supergiants SG and a Barium star Ba). For a description of the {DELTA}a photometric system, see e.g. <GCPD/75>
- ID:
- ivo://CDS.VizieR/J/A+AS/130/215
- Title:
- Effective temperatures of Ap stars
- Short Name:
- J/A+AS/130/215
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new method of determination of the effective temperatures of Ap stars is proposed. The method is based on the fact that the slopes of the energy distribution in the Balmer continuum near the Balmer jump for "normal" main sequence stars and Ap stars with the same effective temperature are identical. The effective temperature calibration is based on a sample of main sequence stars with well known temperatures (Sokolov, 1995, Cat. <J/A+AS/110/553>).
- ID:
- ivo://CDS.VizieR/J/other/BSAO/38.152
- Title:
- Effective temperatures of CP stars
- Short Name:
- J/other/BSAO/38.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new list is presented of effective temperatures estimated for about 700 chemically peculiar stars from the photometric parameters, calibrated with the temperatures determined by Shallis Blackwell (Blackwell et al., 1980A&A....82..249B) method from the total flux of the energy emitted by the stars.
- ID:
- ivo://CDS.VizieR/J/A+A/354/899
- Title:
- Elemental abundance analyses IV.
- Short Name:
- J/A+A/354/899
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using new CASLEO echelle spectrograms, we extended our elemental abundances of the sharp-lines Mercury-Manganese star {mu} Lep, 14 Hya, {kappa} Cnc, HR 4487, 28 Her, and HR 7245, the closely related star 3 CenA, and 7 Sex an A0V star with population I abundances, but with Population II star space motion. The {lambda}{lambda}4500-6200 region contains a sufficient number of lines to derive high-quality abundances of these stars. For most stars, the new spectra provide additional lines for the analyses which improve their quality as well as help fill in the periodic table.
- ID:
- ivo://CDS.VizieR/J/AN/329/4
- Title:
- Elemental abundance analyses of nu Her & 41 Cyg
- Short Name:
- J/AN/329/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This series of high quality elemental abundance analyses of mostly Main Sequence normal and peculiar B, A, and F stars defines their properties and provides data for the comparison with analyses of somewhat similar stars and with theoretical predictions. Most use high dispersion and high S/N (greater than or equal to 200) spectrograms obtained with CCD detectors at the long camera of the 1.22-m Dominion Astrophysical Observatory telescope's coude spectrograph. Here we expand the range of stars examined to include two relatively quiescent F supergiants. nu Her (F2 II) and 41 Cyg (F5 Ib-II) are analyzed as consistently as possible with previous studies. These LTE fine analyses use the ATLAS9 and the WIDTH9 programs of R.L. Kurucz. High signal-to-noise spectrograms and high quality atomic data were employed. The derived values of these photometrically constant stars are somewhat different with the abundances of nu Her being somewhat metal-poor and those of 41 Cyg being crudely solar-like. Our analyses indicate that the basic results of Luck and Wepfer who also studied nu Her and 41 Cyg are not likely to be significantly changed by new studies of all their stars.
