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49 Ari (49 Arietis)


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Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i
This work is the second part of the set of measurements of v sin i forA-type stars, begun by Royer et al. (\cite{Ror_02a}). Spectra of 249 B8to F2-type stars brighter than V=7 have been collected at Observatoirede Haute-Provence (OHP). Fourier transforms of several line profiles inthe range 4200-4600 Å are used to derive v sin i from thefrequency of the first zero. Statistical analysis of the sampleindicates that measurement error mainly depends on v sin i and thisrelative error of the rotational velocity is found to be about 5% onaverage. The systematic shift with respect to standard values fromSlettebak et al. (\cite{Slk_75}), previously found in the first paper,is here confirmed. Comparisons with data from the literature agree withour findings: v sin i values from Slettebak et al. are underestimatedand the relation between both scales follows a linear law ensuremath vsin inew = 1.03 v sin iold+7.7. Finally, thesedata are combined with those from the previous paper (Royer et al.\cite{Ror_02a}), together with the catalogue of Abt & Morrell(\cite{AbtMol95}). The resulting sample includes some 2150 stars withhomogenized rotational velocities. Based on observations made atObservatoire de Haute Provence (CNRS), France. Tables \ref{results} and\ref{merging} are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.125.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/393/897

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

Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions
The FK6 is a suitable combination of the results of the HIPPARCOSastrometry satellite with ground-based data, measured over a longinterval of time and summarized mainly in the FK5. Part III of the FK6(abbreviated FK6(III)) contains additional fundamental stars with directsolutions. Such direct solutions are appropriate for single stars or forobjects which can be treated like single stars. Part III of the FK6contains in total 3272 stars. Their ground-based data stem from thebright extension of the FK5 (735 stars), from the catalogue of remainingSup stars (RSup, 732 stars), and from the faint extension of the FK5(1805 stars). From the 3272 stars in Part III, we have selected 1928objects as "astrometrically excellent stars", since their instantaneousproper motions and their mean (time-averaged) ones do not differsignificantly. Hence most of the astrometrically excellent stars arewell-behaving "single-star candidates" with good astrometric data. Thesestars are most suited for high-precision astrometry. On the other hand,354 of the stars in Part III are Δμ binaries in the sense ofWielen et al. (1999). Many of them are newly discovered probablebinaries with no other hitherto known indication of binarity. The FK6gives, besides the classical "single-star mode" solutions (SI mode),other solutions which take into account the fact that hidden astrometricbinaries among "apparently single-stars" introduce sizable "cosmicerrors" into the quasi-instantaneously measured HIPPARCOS proper motionsand positions. The FK6 gives, in addition to the SI mode, the "long-termprediction (LTP) mode" and the "short-term prediction (STP) mode". TheseLTP and STP modes are on average the most precise solutions forapparently single stars, depending on the epoch difference with respectto the HIPPARCOS epoch of about 1991. The typical mean error of anFK6(III) proper motion in the single-star mode is 0.59 mas/year. This isa factor of 1.34 better than the typical HIPPARCOS errors for thesestars of 0.79 mas/year. In the long-term prediction mode, in whichcosmic errors are taken into account, the FK6(III) proper motions have atypical mean error of 0.93 mas/year, which is by a factor of about 2better than the corresponding error for the HIPPARCOS values of 1.83mas/year (cosmic errors included).

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

The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1995ApJS...99..135A&db_key=AST

Vitesses radiales. Catalogue WEB: Wilson Evans Batten. Subtittle: Radial velocities: The Wilson-Evans-Batten catalogue.
We give a common version of the two catalogues of Mean Radial Velocitiesby Wilson (1963) and Evans (1978) to which we have added the catalogueof spectroscopic binary systems (Batten et al. 1989). For each star,when possible, we give: 1) an acronym to enter SIMBAD (Set ofIdentifications Measurements and Bibliography for Astronomical Data) ofthe CDS (Centre de Donnees Astronomiques de Strasbourg). 2) the numberHIC of the HIPPARCOS catalogue (Turon 1992). 3) the CCDM number(Catalogue des Composantes des etoiles Doubles et Multiples) byDommanget & Nys (1994). For the cluster stars, a precise study hasbeen done, on the identificator numbers. Numerous remarks point out theproblems we have had to deal with.

A new list of effective temperatures of chemically peculiar stars. II.
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Improved Mean Positions and Proper Motions for the 995 FK4 Sup Stars not Included in the FK5 Extension
Not Available

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.

The correction in right ascension of 508 stars determinated with PMO photoelectric transit instrument.
Not Available

MK morphology of AM stars
We present the results of an analysis of the spectra obtained for asample of 27 Am stars. We find evidence for the presence of groups amongthese stars and argue that all Am stars exhibit a pseudoluminosityeffect.

MK morphological study of AM stars at 66 A/mm
The pseudoluminosity effect in the metallic line A-type stars found byAbt and Morgan (1976) is confirmed in a random sample of 27 Am stars.From a morphological study of their spectra in the wavelength interval3850-4400 A at a reciprocal dispersion of 66 A/mm, revised spectraltypes are given on the MK system for their K-line and metallic-linespectra. This shows that: (1) the segregation of weak Am from the Amstars largely agrees with that by Cowley et al. (1969); (2) all thestars in the sample are dwarfs according to their K-line classification;(3) more than 80 percent exhibit the pseudoluminosity effectsignificantly, with their metallic-line spectra resembling a giant oreven a supergiant in the violet (3850-4100 A), and a giant rather than adwarf in the blue region (4260-4400 A); and (4) in two-thirds of thestars under (3), the Sr II 4077 A line is found to have a markedlybrighter luminosity class compared to any region, and in more thanone-third of the sample it is comparable to that in Ap stars. Moreover,at least five stars exhibit characteristics which might suggest aspectrum variability; among these, the most striking example is 41 SexA. The metallic-line spectra of another five stars appear to be similarto A-shell type in different degrees. Less than 20 percent of the samplecomprises stars which do not show any significant differentialluminosity effect; these stars might have been misclassified or perhapsthey are in a quiescent state.

On the Effective Temperatures of Chemically Peculiar Stars
Not Available

Improved study of metallic-line binaries
For the sake of completeness, a new study has been made of the frequencyof binaries among classical metallic-line (Am) stars and of thecharacteristics of these systems. For an initial sample of 60 Am stars,about 20 coude spectra and radial velocities were obtained each. Whencombined with excellent published orbital elements for some systems, thenew material yields 16 SB2s, 20 SB1s, and 20 visual and occultationcompanions not already counted as spectroscopic companions. Extensivedetails are given about the observations, radial velocities, and binaryorbits. Evolutionary expansion during their main sequence lifetime isseen as an additional mechanism (besides tidal braking) acting in closebinaries to lower rotational velocities below 100 km/s.

Rotation velocities of metallic-line stars
The rotation velocities (V sin i) of 81 Am stars were determined usingspectra of dispersion 15 A/mm. The profiles of Fe I 4045 A and Sr II4215 A lines were compared with the computed profiles. The line widthand its ratio to the central depth are found to be most sensitive to therotation velocity. The hydrogen spectral types obtained from the H-gammaequivalent width are also given. It is noted that the extremal Am starHR 4646 has a relatively high rotation velocity of at least 70 km/s.

A catalogue of Fe/H determinations, 1984 edition
The present version of the Cayrel de Strobel et al. (1981) catalog ofFe/H abundance ratio determinations contains 1921 values for 1035 stars,which represents an augmentation over the previous publication of 48 and47 percent, respectively. In addition, the literature search conductedis complete up to December, 1983. Stellar metal abundance, effectivetemperature, spectroscopic gravity, spectral type, and photometricindices are covered.

UBV photometry of FK4 and FK4 supplement stars
Traditional UBV filters, together with a photomultiplier, have been usedin 40-m Cassegrain telescope observations of all northern stars of theFK4 catalog and its supplement, which have heretofore lacked V and V-Bmeasurements. The resulting UBV photometry for 320 stars is presented intabular form.

Lists of photometric AM candidates
The Geneva photometric m parameter (Nicolet and Cramer, 1982) is used inorder to select Am photometric candidates from the Rufener (1981)catalogue. Two lists are given, the first containing field stars and thesecond cluster stars. According to the photometric criteria thediffusion process probably responsible for the Am phenomenon takes placerather quickly as Am candidates are present in young clusters. It isconfirmed that the phenomenon is enhanced by low rotational velocity andhigh metallicity. The age seems to slightly affect the Am phenomenon.

UV photometric data on standard A, F and AM stars observed by S2/68
Data derived from the stellar UV fluxes of the S2/68 experiment andanalyzed and interpreted by Van't Veer et al. (1980) are presented.There are two tables of photometric data. One lists all standard stars,without exception, belonging to the intersection of the following threecatalogs: (1) the Thompson et al. (1978) catalog of S2/68 fluxes; (2)the PMR catalog (Philip et al., 1976), which is an analysis of theHauck-Mermilliod catalog (1975) of homogeneous four color data; and (3)the Crawford and Barnes (1970) list of standard stars for uvbyphotometry. The other table lists all the Am stars, without exception,belonging to the intersection of the following three catalogs: (1)Thompson et al. (1978); (2) PMR (1976); and (3) the Hauck (1973) catalogof the Am stars.

Catalog of profiles and equivalent widths of the CA II K line in the spectra of metallic-line stars
Profiles of the Ca II K line for 87 bright Am, A, and F stars weremeasured on spectrograms with a dispersion of 15 A/mm. Halfwidths of theprofiles for fixed values of line depth, central depths, and equivalentwidths are presented. In contrast to the case of peculiar stars, theobserved K-line profiles in the metallic-line stars do not show anypeculiar structure.

A catalogue of /Fe/H/ determinations
A catalog of iron/hydrogen abundance ratios for 628 stars is compiledbased on 1109 published values. The catalog consists of (1) a table ofabsolute iron abundance determinations in the solar photosphere ascompiled by Blackwell (1974); (2) the iron/hydrogen abundances of 628stars in the form of logarithmic differences between iron abundances inthe given star and a standard star, obtained from analyses ofhigh-dispersion spectra as well as useful stellar spectroscopic andphotometric parameters; and (3) indications of the mean dispersion andwavelength interval used in the analyses. In addition, statistics on thedistributions of the number of determinations per star and the apparentmagnitudes and spectral types of the stars are presented.

Properties of AM stars in the Geneva photometric system
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&A....92..289H&db_key=AST

The rotational velocity effect on the main sequence AM stars metallicity
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1979A&A....74...38B&db_key=AST

Metallicism and pulsation - The marginal metallic line stars
Evidence is presented that HR 4594 and HR 8210 are pulsating marginal Amstars. It is suggested that (1) classical Am stars do not pulsate, (2)evolved Am stars may pulsate, and (3) marginal Am stars may pulsate. Itis further suggested that, within the Am domain, temperature, age,rotation, and pulsation are sufficient to determine whether a star willbe Am, marginal Am, or spectrally normal.

UBVRI photometry of 225 AM stars
UBVRI photometry of 225 Am stars taken from Mendoza's (1974) catalog ispresented. The results are compared with those obtained by Feinstein(1974) for 21 of the stars and with the values of Johnson et al. (1966).It is assumed that in the first approximation the (V-I) color index ofan unreddened Am star is equal to that of a normal main-sequence star; astandard main sequence is defined for A and early F stars, and thefive-color photometry is analyzed by means of plots of U-V vs. V-I, B-Vvs. V-I, and V-R vs. V-I. Mean color deficiencies of Am stars areexamined, and it is suggested that an unreddened star located below themain-sequence A0-F2 line in the (V-I, U-V) plane is a photometric Amstar. It is concluded that: (1) photometric Am stars have colordeficiencies (as a function of V-I) which, on the average, are 0.07 magin (U-V) color index and 0.025 mag in (B-V) color index; (2) Am starswith V-R less than 0.25 mag may also have a color deficiency of about0.01 mag; (3) Am stars with V-R greater than 0.3 mag may have a colorexcess of approximately 0.01 mag; and (4) Am stars with V-R between 0.25and 0.3 mag may have normal colors.

Photoelectric K-line indices for 165 B, A and F stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...34..441P&db_key=AST

Bright metallic-line and pulsating A stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88..402E&db_key=AST

Catalogue of early-type stars measured in a narrow-band photometric system
A compilation of the photoelectric measurements in the Barbier-Morguleffsystem is presented. The catalogue includes data for 773 stars ofspectral type 08 to F6. 706 stars have been measured at least twice.

Multicolor photometry of metallic-line stars. III. A photometric catalogue
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974RMxAA...1..175M&db_key=AST

A Spectroscopic Orbit for the AM Eclipsing System AN Andromedae
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86...63Y&db_key=AST

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Observation and Astrometry data

Constellation:Bélier
Right ascension:03h01m54.10s
Declination:+26°27'44.0"
Apparent magnitude:5.9
Distance:65.617 parsecs
Proper motion RA:-14
Proper motion Dec:5.4
B-T magnitude:6.094
V-T magnitude:5.929

Catalogs and designations:
Proper Names49 Arietis
  (Edit)
Flamsteed49 Ari
HD 1989HD 18769
TYCHO-2 2000TYC 1790-1709-1
USNO-A2.0USNO-A2 1125-00973864
BSC 1991HR 905
HIPHIP 14109

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