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Main-sequence magnetic CP stars III. Results of magnetic field measurements
We present the third part of the survey of magnetic parameters ofmain-sequence magnetic CP stars. We analyze the main definitions andterminology, basic data on the magnetic fields of CP stars (catalogs,the history of the stellar magnetism research, the main observationalresults obtained over 60 years of studies). We describe the modern viewson the properties of magnetic CP stars, i.e. their geometric structure,distribution of field strengths, magnetic field and rotation, magneticfield and energy distribution anomalies, and the evolutionary status ofmagnetic CP stars. We conclude that the observational data mostlysupport the theory of the relict origin and evolution of magnetic fieldsof CP stars.
| Catalogue of Ap, HgMn and Am stars
We present a catalogue of 8205 known or suspected Ap, HgMn and Am stars.This paper is a major update of our first edition of the catalog of Apand Am stars and includes revised identifications, additional stars andrevised information obtained from the literature.Catalogue (full Table 1) is only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/498/961
| Catalogue of averaged stellar effective magnetic fields - II. Re-discussion of chemically peculiar A and B stars
This paper presents a catalogue and the method of determining averagedquadratic effective magnetic fields for 1212main-sequence and giant stars, and 11 white dwarf stars. The catalogueincludes stars that are members of several open clusters. We havecompiled measurements of the longitudinal magnetic field for thosestars, which were scattered in the existing literature. A new parameter,magnetization (MA), has been defined, and we present values of MA forstars of various spectral classes. Our sample includes a subset of 610chemically peculiar early-type stars. We confirm the conclusion of ourprevious study that the number distribution of all chemically peculiarstars versus the averaged magnetic field strength is described by adecreasing exponential function. Relations of this type also hold forstars of all the analysed subclasses of chemical peculiarity.Magnetization tends to correlate with the effective temperature only athigh MA, for He-weak and He-rich stars.
| Magnetic fields of chemically peculiar stars. I. The catalog of magnetic CP stars
This is the first paper of the series dedicated to the analysis of themagnetism of chemically peculiar (CP) stars of the upper Main Sequence.We use our own measurements and published data to compile a catalog ofmagnetic CP stars containing a total of 326 objects with confidentlydetected magnetic fields and 29 stars which are very likely to possessmagnetic field. We obtained the data on the magnetism of theoverwhelming majority of the stars solely based on the analysis oflongitudinal field component B e . The surface magneticfield, B s , has been measured for 49 objects. Our analysisshows that the number of magnetic CP stars decreases with increasingfield strength in accordance with exponential law, and stars with B e exceeding 5kG occur rarely (about 3% objects of ourlist).
| On the HIPPARCOS photometry of chemically peculiar B, A, and F stars
The Hipparcos photometry of the Chemically Peculiar main sequence B, A,and F stars is examined for variability. Some non-magnetic CP stars,Mercury-Manganese and metallic-line stars, which according to canonicalwisdom should not be variable, may be variable and are identified forfurther study. Some potentially important magnetic CP stars are noted.Tables 1, 2, and 3 are available only in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| The HR-diagram from HIPPARCOS data. Absolute magnitudes and kinematics of BP - AP stars
The HR-diagram of about 1000 Bp - Ap stars in the solar neighbourhoodhas been constructed using astrometric data from Hipparcos satellite aswell as photometric and radial velocity data. The LM method\cite{luri95,luri96} allows the use of proper motion and radial velocitydata in addition to the trigonometric parallaxes to obtain luminositycalibrations and improved distances estimates. Six types of Bp - Apstars have been examined: He-rich, He-weak, HgMn, Si, Si+ and SrCrEu.Most Bp - Ap stars lie on the main sequence occupying the whole width ofit (about 2 mag), just like normal stars in the same range of spectraltypes. Their kinematic behaviour is typical of thin disk stars youngerthan about 1 Gyr. A few stars found to be high above the galactic planeor to have a high velocity are briefly discussed. Based on data from theESA Hipparcos astrometry satellite and photometric data collected in theGeneva system at ESO, La Silla (Chile) and at Jungfraujoch andGornergrat Observatories (Switzerland). Tables 3 and 4 are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Discovery of a very large magnetic field in three AP stars.
We report the discovery of magnetic fields larger than 11 kG in thethree Ap SrCrEu stars BD +40^o^ 175, HD 63843 and HD 86592. In addition,we give new results for the star HD 47103, where the correlation peak isresolved into magnetically split components. The average (quadratic)surface field measured by correlation methods in the three newlymeasured stars is 16, 12 and 16kG respectively. Their effectivetemperatures, estimated from the profile of the Balmer lines, are 7100,7500 and 7600K. The projected rotational velocities are 17, <5 and16km/s respectively, so that two of these objects are not extremely slowrotators. One object, BD +40^o^ 175, is particularly interesting as itundergoes a strong variation of the magnetic field on a timescale ofdays with extreme values at 12.8 and 22kG, together with a largevariation of the radial velocity measured in Hα and Hβindicating a probable close SB1 system. For HD 86592, a period P=2.887days is also determined from Geneva photometry. Our new measurements ofHD 47103 do not show any relative variation of larger than 1%compared with those of April 1995, suggesting that the rotational periodof this star might be very long, of the order of years. It shows,however, a significant shift in v_rad_ indicating a membership in abinary system
| General catalogue of AP and AM stars
A catalog of all the known Ap and Am stars, containing a total of 6684objects, was prepared. The few stars that were wrongly considered as Apor Am star are noted as well as some others for which their identity asAp or Am stars is not yet well established. The catalog gives theidentificators and the main observational data for each star, includingthe magnitude, color, spectral type, duplicity, periodicity, magneticfield, and projected rotational velocity.
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Osservazione e dati astrometrici
| Costellazione: | Unicorno |
| Ascensione retta: | 07h50m41.80s |
| Declinazione: | -06°03'38.3" |
| Magnitudine apparente: | 10.254 |
| Moto proprio RA: | -1.2 |
| Moto proprio Dec: | 2 |
| B-T magnitude: | 10.59 |
| V-T magnitude: | 10.282 |
Cataloghi e designazioni:
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