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Публикации по объекту
Evolutionary state of magnetic chemically peculiar stars
Context: .The photospheres of about 5-10% of the upper main sequencestars exhibit remarkable chemical anomalies. Many of these chemicallypeculiar (CP) stars have a global magnetic field, the origin of which isstill a matter of debate. Aims: .We present a comprehensivestatistical investigation of the evolution of magnetic CP stars, aimedat providing constraints to the theories that deal with the origin ofthe magnetic field in these stars. Methods: .We have collectedfrom the literature data for 150 magnetic CP stars with accurateHipparcos parallaxes. We have retrieved from the ESO archive 142 FORS1observations of circularly polarized spectra for 100 stars. From thesespectra we have measured the mean longitudinal magnetic field, anddiscovered 48 new magnetic CP stars (five of which belonging to the rareclass of rapidly oscillating Ap stars). We have determined effectivetemperature and luminosity, then mass and position in the H-R diagramfor a final sample of 194 magnetic CP stars. Results: .We foundthat magnetic stars with M > 3 ~M_ȯ are homogeneouslydistributed along the main sequence. Instead, there are statisticalindications that lower mass stars (especially those with M ≤2~M_ȯ) tend to concentrate in the centre of the main sequence band.We show that this inhomogeneous age distribution cannot be attributed tothe effects of random errors and small number statistics. Our datasuggest also that the surface magnetic flux of CP stars increases withstellar age and mass, and correlates with the rotation period. For starswith M > 3~M_ȯ, rotation periods decrease with age in a wayconsistent with the conservation of the angular momentum, while for lessmassive magnetic CP stars an angular momentum loss cannot be ruledout. Conclusions: .The mechanism that originates and sustains themagnetic field in the upper main sequence stars may be different in CPstars of different mass.
| An elemental abundance analysis of the magnetic chemically peculiar star HR 8216
An elemental abundance analysis of the cool magnetic CP star HR 8216 (=HD204411) was performed using 2.4 Åmm-1 DominionAstrophysical Observatory Reticon exposures coveringλλ3830-4770 with a typical signal-to-noise ratio of 200taken with the long camera of the 1.22-m telescope. The spectrogramswere measured interactively with the graphics computer program REDUCE.The fine analysis used an ATLAS9 metal-rich model atmosphere, thepredictions of which best-matched the optical region fluxes and theHγ profile. The anomalies of HR 8216 are primarily an enhancementof many iron peak elements with the rare earths elements much lessenhanced than in many similar cool magnetic CP stars. Using the resultsof the fine analysis the spectrum was synthesized. Comparison with theobserved spectrum showed that the agreement is good but did not fullyaccount for all of the observed line spectrum.
| A catalog of stellar magnetic rotational phase curves
Magnetized stars usually exhibit periodic variations of the effective(longitudinal) magnetic field Be caused by their rotation. Wepresent a catalog of magnetic rotational phase curves, Be vs.the rotational phase φ, and tables of their parameters for 136stars on the main sequence and above it. Phase curves were obtained bythe least squares fitting of sine wave or double wave functions to theavailable Be measurements, which were compiled from theexisting literature. Most of the catalogued objects are chemicallypeculiar A and B type stars (127 stars). For some stars we also improvedor determined periods of their rotation. We discuss the distribution ofparameters describing magnetic rotational phase curves in our sample.All tables and Appendix A are only available in electronic form athttp://www.edpsciences.org
| Revised Elemental Abundances of the MCP Star HD 8441
We present new elemental abundances of the mCP star HD 8441 previouslyanalyzed by the first author by using improved gf values and ATLAS9model atmospheres. The elemental abundances range from those which aregreatly underabundant such as Ca and Sc to those very overabundant suchas Cr, Sr and the rare earths.
| Spectral Classification of Stars in A Supplement to the Bright Star Catalogue
MK spectral types are given for about 584 stars in A Supplement to theBright Star Catalogue. These are compared with Hipparcos parallaxes tocheck the reliability of those classifications. The estimated errors are+/-1.2 subtypes, and 10% of the luminosity classes may be wrong.
| Catalogue of averaged stellar effective magnetic fields. I. Chemically peculiar A and B type stars
This paper presents the catalogue and the method of determination ofaveraged quadratic effective magnetic fields < B_e > for 596 mainsequence and giant stars. The catalogue is based on measurements of thestellar effective (or mean longitudinal) magnetic field strengths B_e,which were compiled from the existing literature.We analysed the properties of 352 chemically peculiar A and B stars inthe catalogue, including Am, ApSi, He-weak, He-rich, HgMn, ApSrCrEu, andall ApSr type stars. We have found that the number distribution of allchemically peculiar (CP) stars vs. averaged magnetic field strength isdescribed by a decreasing exponential function. Relations of this typehold also for stars of all the analysed subclasses of chemicalpeculiarity. The exponential form of the above distribution function canbreak down below about 100 G, the latter value representingapproximately the resolution of our analysis for A type stars.Table A.1 and its references are only available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/407/631 and Tables 3 to 9are only available in electronic form at http://www.edpsciences.org
| Multiplicity among chemically peculiar stars. II. Cool magnetic Ap stars
We present new orbits for sixteen Ap spectroscopic binaries, four ofwhich might in fact be Am stars, and give their orbital elements. Fourof them are SB2 systems: HD 5550, HD 22128, HD 56495 and HD 98088. Thetwelve other stars are: HD 9996, HD 12288, HD 40711, HD 54908, HD 65339,HD 73709, HD 105680, HD 138426, HD 184471, HD 188854, HD 200405 and HD216533. Rough estimates of the individual masses of the components of HD65339 (53 Cam) are given, combining our radial velocities with theresults of speckle interferometry and with Hipparcos parallaxes.Considering the mass functions of 74 spectroscopic binaries from thiswork and from the literature, we conclude that the distribution of themass ratio is the same for cool Ap stars and for normal G dwarfs.Therefore, the only differences between binaries with normal stars andthose hosting an Ap star lie in the period distribution: except for thecase of HD 200405, all orbital periods are longer than (or equal to) 3days. A consequence of this peculiar distribution is a deficit of nulleccentricities. There is no indication that the secondary has a specialnature, like e.g. a white dwarf. Based on observations collected at theObservatoire de Haute-Provence (CNRS), France.Tables 1 to 3 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/394/151Appendix B is only available in electronic form athttp://www.edpsciences.org
| Surface abundance distribution models of Si, Cr, Mn, Fe, Pr and Nd for the slowly rotating Ap star HD 187474
The very slowly rotating magnetic Ap star HD 187474 has strong and quitevariable spectral lines of several elements. An axisymmetric low-ordermultipole magnetic model has been obtained for this star by Landstreet& Mathys (2000). HD 187474 is one of the few very slowly rotatingmagnetic Ap stars that is suitable for abundance distribution modelling;because of the unusually large angle between the field and rotationaxes, the line of sight goes well into both magnetic hemispheres. Wehave used CASPEC and CES spectra with good phase coverage together withthe programme ZEEMAN to search for simple three-ring abundancedistributions of Si, Cr, Mn, Fe, Pr and Nd, symmetric about the assumedmagnetic field distribution axis, that match observed line profiles as afunction of rotational phase. Reasonably satisfactory fits to theobservations are found for all of these elements. In all cases,three-ring models work as well as more finely gridded models. Thededuced abundances are somewhat overabundant and somewhat non-uniformfor Fe; for the other elements quite large overabundances (up to 5 dexfor Nd) are found, with substantially higher (but somewhat unequal)abundances around the two magnetic poles compared to the magneticequator. All the elements studied are overabundant everywhere (exceptperhaps Si around the magnetic equator). This star poses a realchallenge to theories of chemical peculiarity. Based on observationscollected at the European Southern Observatory, La Silla, Chile.
| Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics
The Catalogue, available at the Centre de Données Stellaires deStrasbourg, consists of 13 573 records concerning the results obtainedfrom different methods for 7778 stars, reported in the literature. Thefollowing data are listed for each star: identifications, apparentmagnitude, spectral type, apparent diameter in arcsec, absolute radiusin solar units, method of determination, reference, remarks. Commentsand statistics obtained from CADARS are given. The Catalogue isavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcar?J/A+A/367/521
| Analysis of the Photospheric Lines of the Magnetic CP Star HR 7575
The photospheric lines in the visual region of the cool magnetic CP starHR 7575 have been analyzed using a high-dispersion spectrogram obtainedat the Dominion Astrophysical Observatory. The fully line-blanketedATLAS9 model atmospheres of 10-times the solar metal content wereemployed to calculate the elemental abundances. The effectivetemperature T_eff, derived from the optical and ultraviolet energydistributions, points to 8500 +/- 300 K, while the ionization balance ofiron is not reproduced at this effective temperature. The abundancesderived from individual Cr I, Cr II, and Fe II lines apparently dependon their effective Lande factors. This implies that the Cr and Fe linesare intensified by the strong magnetic field on HR 7575. Their abundanceenhancement is estimated to be about 0.7 dex based on a computation ofthe Unno--Beckers equation. The overall abundance patterns of HR 7575are comparable to other cool magnetic CP stars. Of the analyzedelements, only Mg and Sc have nearly solar abundances, while Cr, Mn, Sr,and rare earths are overabundant by 1 to 5 dex.
| Do the physical properties of Ap binaries depend on their orbital elements?
We reveal sufficient evidence that the physical characteristics of Apstars are related to binarity. The Ap star peculiarity [represented bythe Δ(V1-G) value and magnetic field strength] diminishes witheccentricity, and it may also increase with orbital period(Porb). This pattern, however, does not hold for largeorbital periods. A striking gap that occurs in the orbital perioddistribution of Ap binaries at 160-600d might well mark a discontinuityin the above-mentioned behaviour. There is also an interestingindication that the Ap star eccentricities are relatively lower thanthose of corresponding B9-A2 normal binaries for Porb>10d.All this gives serious support to the pioneering idea of Abt &Snowden concerning a possible interplay between the magnetism of Apstars and their binarity. Nevertheless, we argue instead in favour ofanother mechanism, namely that it is binarity that affects magnetism andnot the opposite, and suggest the presence of a newmagnetohydrodynamical mechanism induced by the stellar companion andstretching to surprisingly large Porb.
| Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
| 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
| Multiplicity among peculiar A stars. I. The AP stars HD 8441 and HD 137909, and the AM stars HD 43478 and HD 96391
We present the first results of a radial-velocity survey of cool Ap andAm stars. HD 8441 is not only a double system with P = 106.357 days, butis a triple one, the third companion having an orbital period largerthan 5000 days. Improved orbital elements are given for the classical Apstar HD 137909 = beta CrB by combining our radial velocities withpublished ones. We yield new orbital elements of the two Am, SB2binaries HD 43478 and HD 96391. Good estimates of the individual massesof the components of HD 43478 can be given thanks to the eclipses ofthis system, for which an approximate photometric solution is alsoproposed. Based on observations made at the Observatoire de HauteProvence (CNRS), France, at the Jungfraujoch station of Observatoire deGeneve, Switzerland, and on data from the ESA Hipparcos satellite.Tables 6 to 12 are only available 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 observed periods of AP and BP stars
A catalogue of all the periods up to now proposed for the variations ofCP2, CP3, and CP4 stars is presented. The main identifiers (HD and HR),the proper name, the variable-star name, and the spectral type andpeculiarity are given for each star as far as the coordinates at 2000.0and the visual magnitude. The nature of the observed variations (light,spectrum, magnetic field, etc.) is presented in a codified way. Thecatalogue is arranged in three tables: the bulk of the data, i.e. thosereferring to CP2, CP3, and CP4 stars, are given in Table 1, while thedata concerning He-strong stars are given in Table 2 and those foreclipsing or ellipsoidal variables are collected in Table 3. Notes arealso provided at the end of each table, mainly about duplicities. Thecatalogue contains data on 364 CP stars and is updated to 1996, October31. This research has made use of the SIMBAD database, operated at CDS,Strasbourg, France.
| Spectroscopic and photometric investigations of MAIA candidate stars
Including our own observational material and the Hipparcos photometrydata, we investigate the radial velocity and brightness of suspectedMaia variable stars which are classified also in some examples aspeculiar stars, mainly for the existence of periodic variations withtime-scales of hours. The results lead to the following conclusions: (1)Short-term radial velocity variations have been unambiguously proved forthe A0 V star gamma CrB and the A2 III star gamma UMi. The stars pulsatein an irregular manner. Moreover, gamma CrB shows a multiperiodstructure quite similar to some of the best-studied neighbouring deltaScu stars. (2) In the Hipparcos photometry as well as in our photometricruns we find significant short- and long-term variations in the stars HD8441, 2 Lyn, theta Vir, gamma UMi, and gamma CrB. For ET And theHipparcos data confirm a short-period variation found already earlier.Furthermore, we find changes of the colour index in theta Vir and gammaCrB on a time-scale of days. (3) No proofs for the existence of aseparate class of variables, designated as Maia variables, are found. Ifthe irregular behaviour of our two best-investigated stars gamma CrB andgamma UMi is typical for pulsations in this region of theHertzsprung-Russell diagram, our observational runs are too short andthe accuracy of the measurements too low to exclude such pulsations inthe other stars, however. (4) The radial velocities of the binariesalpha Dra and ET And have been further used for a recalculation of theorbital elements. For HD 8441 and 2 Lyn we estimated the orbitalelements for the first time. (5) Zeeman observations of the stars gammaGem, theta Vir, alpha Dra, 4 Lac, and ET And give no evidence of thepresence of longitudinal magnetic field strengths larger than about 150gauss. Based on spectroscopic observations taken with the 2\,m telescopeat the Th{ü
| 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
| A catalogue of [Fe/H] determinations: 1996 edition
A fifth Edition of the Catalogue of [Fe/H] determinations is presentedherewith. It contains 5946 determinations for 3247 stars, including 751stars in 84 associations, clusters or galaxies. The literature iscomplete up to December 1995. The 700 bibliographical referencescorrespond to [Fe/H] determinations obtained from high resolutionspectroscopic observations and detailed analyses, most of them carriedout with the help of model-atmospheres. The Catalogue is made up ofthree formatted files: File 1: field stars, File 2: stars in galacticassociations and clusters, and stars in SMC, LMC, M33, File 3: numberedlist of bibliographical references The three files are only available inelectronic form at the Centre de Donnees Stellaires in Strasbourg, viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5), or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| On the effective temperatures, surface gravities, and optical region fluxes of the magnetic CP stars.
We determined effective temperatures and surface gravities for five MCPstars using ATLAS9 metal-rich model atmospheres, optical regionspectrophotometry, and Hγ profiles. The predictions of thesemodels fit the continua significantly better than do those of previousgeneration ATLAS models. They can even match the 5200A broad, continuumfeatures in three stars where this feature is of moderate strength. Asynthesized spectrum of one of these stars, HD 43819, suggests that thisfeature is at least due partially to differential line blanketing.However, problems remain in fitting the optical region energydistributions of stars with stronger 5200A features. The 4200A and the6300A features are not reproduced in the models. The relationshipbetween the strength of the 5200A feature and metallicity was alsoexplored using spectrophotometric and photometric indices.
| The Cape rapidly oscillating AP star survey - III. Null results of searches for high-overtone pulsation.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1994MNRAS.271..129M&db_key=AST
| A new list of effective temperatures of chemically peculiar stars. II.
Not Available
| Elemental abundance studies of CP stars: The silicon star HD 43819 and the CP star HD 147550.
Fine analyses of the silicon star HD 43819 and the CP star HD 147550 arepresented using ATLAS9 model atmospheres whose predictions fit theoptical region spectrophotometry and Hγ profiles and have the samebulk metallicity as the deduced abundances. For HD 43819 except forscandium and nickel, the derived abundances of the iron peak elementsare around 10 times solar while those of the rare earths are about 1000times solar. The lighter elements are generally underabundant except forsilicon and calcium which are overabundant. HD 147550 is helium andcalcium poor; carbon, magnesium, aluminum, scandium, titanium, and ironnormal; and sulfur, chromium, manganese, nickel, strontium, zirconium,barium, europium, and mercury rich. It is a nonmagnetic CP starintermediate between the HgMn and the hot Am stars.
| Catalogue of CP stars with references to short time scale variability
A catalogue was compiled which contains all references in the literaturesince 1962 related to variations of CP stars on time scales shorter thanthe rotation period. The role of this catalogue lies in the unbiasedlisting of all available references, and not in a critical evaluation.
| Investigation of stellar magnetic fields based on the strengths of spectral lines - Application to Omicron Pegasi and Cool AP Stars
A practical method for simultaneous determinations of H (magnetic field)and xi (microturbulence) in a stellar atmosphere is presented, which isbased on the requirement that the scatter of the abundances derived fromindividual lines should be minimized for the best choice of H and xi.This procedure may be regarded as being an improved and extended versionof the classical Hensberge-De Loore method, since it is based on a 'fineanalysis' technique using a model atmosphere and the detailedZeeman-split components of a line are explicitly taken into account withan approximate treatment of the polarization effect. This method wasfirst applied to the hot Am star O Peg, resulting in H = 2 kG (and xi isabout 1.5 km/s); this H value is fairly consistent with other estimatesbased either on the Stenflo-Lindegren technique or on the line-pairmethod. As an alternative application, surface magnetic fields of fivecool Ap stars were also investigated, showing that the H-values by thismethod agree well with those derived from the method of differentialZeeman broadening and that the classical Hensberge-De Loore techniquetends to yield somewhat underestimated values.
| A seven-year northern sky survey of AP stars for rapid variability
A high-speed photometric survey of 120 Ap stars in the northern sky, hasbeen conducted, between 1985 and 1991, in order to search for rapidvariability. Stars of spectral types, namely from B8 to F4, have beenselected for the survey. The selected pulsational variable stars occupythe hotter regions of the instability strip of the Hertzsprung-Russeldiagram. Noted is the absence of pulsations in the hotter B8-A3 Apstars; this does not, however, preclude the existence of pulsations,since HD 218495 was recently discovered to be a rapidly oscillating Ap(roAp) star. The primary result of this study is that variouscombinations of photometric indices, while pointing towards roAp starshaving the characteristic signatures of cool, SrCrEu stars, still failto isolate the roAp phenomenon from similar nonpulsating Ap stars.Color-magnitude and color-color diagrams are presented in order tocomplete this survey.
| Spectrophotometry of Peculiar B-Stars and A-Stars - Part Nineteen - Variability of the Magnetic Cp-Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1993A&AS..101..393A&db_key=AST
| A catalogue of Fe/H determinations - 1991 edition
A revised version of the catalog of Fe/H determinations published by G.Cayrel et al. (1985) is presented. The catalog contains 3252 Fe/Hdeterminations for 1676 stars. The literature is complete up to December1990. The catalog includes only Fe/H determinations obtained from highresolution spectroscopic observations based on detailed spectroscopicanalyses, most of them carried out with model atmospheres. The catalogcontains a good number of Fe/H determinations for stars from open andglobular clusters and for some supergiants in the Magellanic Clouds.
| AP stars with resolved magnetically split lines
New high-resolution spectroscopic observations of Ap stars with resolvedmagnetically split spectral lines are presented. Six new such stars havebeen discovered: HD 2453, HD 9996, HD 18078, HD 50169, HD 137949, and HD192678. This raises the total number of known Ap stars with resolvedmagnetically split lines to 21. The spectral line profiles observed intwo more stars, HD 111133 and HD 147010, are strongly affected by themagnetic field, but they are not fully resolved, due to nonnegligiblerotational Doppler effect. Observations of fairly sharp-lined Ap starswhose lines are unresolved are also presented. The relative differencebetween the equivalent widths of the Fe II lines 6147.7 A and 6149.2 Ais shown to increase with the mean magnetic field modulus. The existenceof a simple, unambiguous correlation between the mean magnetic fieldmodulus and the index Z of Geneva photometry, which had previously beenadvocated, is not confirmed. At most, stars with large negative valuesof Z may be more prone to have strong magnetic fields, but the evidencefor this is not statistically strong.
| The third spectrum of praseodymium in magnetic AP stars
The identification of Pr III lines in the red spectrum of magnetic Apstars, whose great strength contrasts with the weakness of the secondspectrum of Pr in upper main-sequence, chemically peculiar stars, ispresently reported. This identification is judged to be a critical steptoward a knowledge of the abundance systematics of the lanthanides inchemically peculiar stars, as well as toward characterization of thechemical fractionation processes which they undergo.
| Relative strengths of multiplet lines as an indicator of stellar magnetic fields
The magnetic intensification of coupled Fe II lines belonging to acommon multiplet is theoretically investigated, where the relativedifference (delta) in the line-strength is a good indicator of themagnetic field (H). It is shown that delta is not only a function of H,but also depends upon various other parameters; its behavior iscontrolled by the ratio of the Zeeman width to the Doppler width, aswell as by the difference in component-patterns. Theoretical delta vs. Hrelations are applied to the hot Am star Omicron Peg with the results ofH about 2-3 kG and microturbulence about 0 km/s, suggesting that theconventionally derived microturbulence-value of about 2 km/s may simplyreflect the magnetic effect. As an alternative application, an empiricalcorrelation between delta vs. H for cool Ap stars is examined and foundto be consistent with the calculations.
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Наблюдательные данные и астрометрия
| Созвездие: | Андромеда |
| Прямое восхождение: | 01h24m18.67s |
| Склонение: | +43°08'31.5" |
| Видимая звёздная величина: | 6.675 |
| Расстояние: | 203.666 парсек |
| Собственное движение RA: | -2.6 |
| Собственное движение Dec: | -9.7 |
| B-T magnitude: | 6.716 |
| V-T magnitude: | 6.679 |
Каталоги и обозначения:
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