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HD 6226 (V442 And )


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The 78th Name-List of Variable Stars
We present the next regular Name-List of variable stars containinginformation on 1706 variable stars recently designated in the system ofthe General Catalogue of Variable Stars.

Properties and nature of Be stars. XXII. Long-term light and spectral variations of the new bright Be star HD 6226
Photometric and spectroscopic monitoring of the B star HD 6226 resultedin the finding that this object is a new bright Be star with a clearpositive correlation between the brightness and emission-line strength.The emission-line episodes are relatively short and seem to repeatfrequently which makes this star an ideal target for studying the causesof the Be phenomenon. The general character of the light variations, thelow v sin i = 70 km s-1 and the very pronounced lineasymmetries of the He I 6678 line, seen both outside and duringemission-line episodes, are all attributes which make HD 6226phenomenologically very similar to the well-known Be star ω CMa.Radial velocities of the deepest parts of the metallic and He I 6678absorption lines vary with a strict period of 2.61507 d over the wholetime interval covered by the observations, the velocities of the broadouter wings of the same lines varying in anti-phase and with a loweramplitude. This periodicity could not be found in the radial-velocityvariations of the sharp core of Hα. There is some indication ofvariability on a time scale of 24-29 days but our data are insufficientto prove that conclusively. A comparison of the line spectrum obtainedoutside emission episodes with synthetic spectra, standard dereddeningof U BV magnitudes and Hipparcos parallax all agree with the conclusionthat HD 6226 is a star with the following basic properties:Teff ,= 17 000 K, log g = 3.0 [cgs], mass of 5m.s and radiusof 11 Rȯ. The strong emission-line episodes may appearregularly, in a cycle of 630 days but with different durations ofindividual cycles. HD 6226 is probably one of the first B stars forwhich the Be nature was predicted on the basis of the character of itslight and colour changes.Based on spectral and photometric observations from the followingobservatories: Castanet-Tolosan, Dominion Astrophysical Observatory,Heidelberg, Hvar, Ondřejov, Skalnaté Pleso andStará Lesná and also on photoelectric photometry by AAVSOmembers.Tables 2 and 4 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/cgi-bin/qcat?J/A+A/416/669

HD 6226: a new bright B variable with occasional brightenings. Is it an unrecognized Be star?
An analysis of differential UBV measurements of HD 6226 secured between1982 and 1995 at Hvar, and combined with the Hipparcos satellite H_pphotometry, led to the finding that this infrequently observed star is anew variable, characterized by occasional brightenings accompanied bythe reddening of the B-V, and blueing of the U-B index. We note thatsuch behaviour was found for several Be stars like QR Vul or o Cas andit would be of interest to check whether also HD 6226 is not anunrecognized Be star. A period analysis of the photometric dataindicates a possibility that the brightenings may occur periodically,with a period of 481.3 d. However, this finding needs to be tested sinceseveral other possible periods were also detected. Moreover, there is noa priori reason to believe that the brightenings must occur in regularintervals. If there is indeed a 481-d periodicity, then the nearestbrightening should occur around Nov. 27, 1998. A spectroscopic study ofthe star will be crucial for a better understanding of its nature butfurther photometric monitoring is also very desirable.

The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle
The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.

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.

Spectral types of 80 early-type stars of variable radial velocity
MK spectral types are given for 80 normal early-type stars of variableradial velocity. These spectral types were determined from spectrogramstaken with the Lick Observatory 0.9-m refractor during the years1957-58.

Catalog of O-B stars observed with Tokyo Meridian Circle
A catalog of the O-B stars, selected from 'Blaauw-Parenago' list andRubin's catalog, has been compiled on the FK4 system by the observationsmade with Gautier 8-inch Meridian Circle at the Tokyo AstronomicalObservatory during the period, 1971 to 1979. It contains 1059 stars andwas compiled for the future establishment of high precision propermotions of O-B stars.

21-cm observations of nonplanar H I associated with the Perseus spiral arm
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1977AJ.....82..886G&db_key=AST

UVBY beta photometry and MK spectral classification.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976A&AS...24...69O&db_key=AST

UBV photometry of 180 early-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..795G&db_key=AST

Spectral Classifications of 239 Early-Type Stars
Not Available

Observations spectrographiques d'etoiles A a spectre particulier et a raies metalliques.
Not Available

Catalogue d'etoiles O et B.
Not Available

Luminous stars in a region south of h and chi Persei. With 3 Figures in the Text
Not Available

Catalogue et bibliographie des étoiles A à spectre particulier - Deuxième supplément
Not Available

Troisième catalogue de l'Observatoire de Besançon comprenant 764 étoiles réduites à 1950, 0 sans mouvement propre et 326 étoiles FK3 pour l'époque moyenne d'observation
Not Available

Photoelectric distances of 461 Northern OB-stars and galactic structure from Hγ- luminosities Author: Beer, A.
Abstract image available at:http://adsabs.harvard.edu/abs/1964MNRAS.128..261B

Catalogue et bibliographie des étoiles A à spectre particulier Premier supplément
Not Available

Catalogue et bibliographie des étoiles A à spectre particulier
Not Available

A Catalog of Magnetic Stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1958ApJS....3..141B&db_key=AST

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Osservazione e dati astrometrici

Costellazione:Andromeda
Ascensione retta:01h03m53.36s
Declinazione:+47°38'32.3"
Magnitudine apparente:6.787
Distanza:884.956 parsec
Moto proprio RA:-6.7
Moto proprio Dec:-3.4
B-T magnitude:6.724
V-T magnitude:6.782

Cataloghi e designazioni:
Nomi esattiV442 And
  (Edit)
HD 1989HD 6226
TYCHO-2 2000TYC 3267-1681-1
USNO-A2.0USNO-A2 1350-01056396
HIPHIP 4983

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