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HD 44867


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Публикации по объекту

A catalog of rotational and radial velocities for evolved stars
Rotational and radial velocities have been measured for about 2000evolved stars of luminosity classes IV, III, II and Ib covering thespectral region F, G and K. The survey was carried out with the CORAVELspectrometer. The precision for the radial velocities is better than0.30 km s-1, whereas for the rotational velocity measurementsthe uncertainties are typically 1.0 km s-1 for subgiants andgiants and 2.0 km s-1 for class II giants and Ib supergiants.These data will add constraints to studies of the rotational behaviourof evolved stars as well as solid informations concerning the presenceof external rotational brakes, tidal interactions in evolved binarysystems and on the link between rotation, chemical abundance and stellaractivity. In this paper we present the rotational velocity v sin i andthe mean radial velocity for the stars of luminosity classes IV, III andII. Based on observations collected at the Haute--Provence Observatory,Saint--Michel, France and at the European Southern Observatory, LaSilla, Chile. Table \ref{tab5} also available in electronic form at CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html

Surface inhomogeneities and line variability on DF Tau
We have mapped surface inhomogeneities on the classical T Tauri star DFTau, using the Lii doublet at 670.8 nm, the Cai lines at 612.2 nm and643.9 nm and a calcium and iron blend at 646.3 nm. We find compellingevidence that there are hotspots with temperatures of more than 5000 K.Two of the hotspots produce line-profile deformations that can be tracedas they move through the cross-correlated profiles. When one of thehotspots crosses the stellar disc, redshifted absorption componentsappear in the Na D lines. As these redshifted absorption features areusually tracers for mass-infall we interpret this hotspot as anaccretion shock close to the stellar surface. Parts of the surface of DFTau are covered with a hot chromosphere that is visible in the Caiiinfrared triplet lines and the narrow component of Hei. We find nocorrelation between the veiling and the lines that originate from thehot chromosphere, suggesting that the veiling and the chromosphericemission are produced in physically distinct regions.

Library of high-resolution UES echelle spectra of F, G, K and M field dwarf stars
We present a library of Utrecht echelle spectrograph (UES) observationsof a sample of F, G, K and M field dwarf stars covering the spectralrange from 4800 \ Angstroms to 10600 \ Angstroms with a resolution of55000. These spectra include some of the spectral lines most widely usedas optical and near-infrared indicators of chromospheric activity suchas Hβ , Mg i b triplet, Na i D1, D2, He iD3, Hα , and Ca ii IRT lines, as well as a large numberof photospheric lines which can also be affected by chromosphericactivity. The spectra have been compiled with the aim of providing a setof standards observed at high-resolution to be used in the applicationof the spectral subtraction technique to obtain the active-chromospherecontribution to these lines in chromospherically active single andbinary stars. This library can also be used for spectral classificationpurposes. A digital version with all the spectra is available via ftpand the World Wide Web (WWW) in both ASCII and FITS formats. Based onobservations made with the William Herschel Telescope operated on theisland of La Palma by the Isaac Newton Group at the Spanish Observatoriodel Roque de Los Muchachos of the Instituto de Astrof\'{\i

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.

Evolved GK stars near the sun. I - The old disk population
A sample of nearly two thousand GK giants with intermediate band, (R,I),DDO and Geneva photometry has been assembled. Astrometric data is alsoavailable for most of the stars. The some 800 members of the old diskpopulation in the sample yield accurate luminosities (from two sources),reddening values and chemical abundances from calibrations of thephotometric parameters. Less than one percent of the objects arepeculiar in the sense that the flux distribution is abnormal. Thepeculiarity is signaled by strong CH (and Ba II) and weak CH. The CH+stars are all spectroscopic binaries, probably with white dwarfcompanions, whereas the CH- stars are not. A broad absorption band,centered near 3500 A, is found in the CH+ stars whereas the CH- objectshave a broad emission feature in the same region. The intensity of theseabsorptions and emissions are independent of the intensity of abnormalspectral features. Ten percent of the old disk sample have a heavyelement abundance from one and a half to three times the solar value.The distribution of the heavy element abundances is nearly a normal onewith a peak near solar abundance and ranges three times to one sixthsolar. The distribution of the (U, V) velocities is independent of theheavy element abundance and does not appear to be random. Ten percent ofthe old disk stars show a CN anomaly, equally divided between CN strongand CN weak. Several stars of individual astrometric or astrophysicalimportance are isolated.

Radial-velocity measurements. V - Ground support of the HIPPARCOS satellite observation program
The paper presents data on 1070 radial velocity measurements of starsdistributed in 39 fields measuring 4 deg x 4 deg. The PPO series ofFehrenbach et al. (1987) and Duflot et al. (1990) is continued using theFehrenbach objective prism method.

Long-term photometry of variables at ESO. I - The first data catalogue (1982-1986)
This paper presents the catalog of photometric data in the Stromgrensystem obtained during the first four years (October 1982 - September1986) of the Long-Term Photometry of Variables (LTPV) program at ESO.The data are available in computer-readable form.

Large and kinematically unbiased samples of G- and K-type stars. IV - Evolved stars of the old disk population
Modified Stromgren and (R,I) photometry, along with DDO and Genevaphotometry, are presented for a complete sample of evolved old-disk Gand K giants in the Bright Star Catalogue. Stars with ages of between1.5 x 10 to the 9th and 10 to the 10th yr are found to have anear-normal distribution of heavy element abundances, centered on anFe/H abundance ratio of -0.1 dex. The old disk clusters NGC 3680 and IC4651 contain red-straggler young-disk giants that are probablycontemporaries of the blue stragglers in the clusters.

Large and kinematically unbiased samples of G- and K-type stars. II - Observations of evolved stars in the Bright Star sample. III - Evolved young disk stars in the Bright Star sample
Four color and RI observations were obtained for a large sample ofG-type and K-type stars in the Bright Star Catalogue. Data are firstpresented for 110 evolved stars. Photometry of evolved young diskpopulation stars have then been calibrated for luminosity, reddening,and metallicity on the basis of results for members of the Hyades andSirius superclusters. New DDO results are given for 120 stars.

Narrow-band photometry of late-type stars. II
This paper presents extensive narrow-band photometry in the Uppsalasystem supplementing earlier published mesurements so that data now areavailable for all late-type stars brighter than V = 6.05 and a number ofgalactic cluster members. Numerous UBV and BV measurements are alsopublished. The data are used to determine relations for the predictionof UBV intrinsic colors for late-type stars from the narrow-bandmeasurements. The main purpose of the data is to constitute the basisfor the determination of solar-neighborhood space densities of late-typestars, mainly giants of different kinds; these space densities will becombined with narrow-band data for fainter stars in the north Galacticpole region to yield the decrease of space density with distance fromthe galactic plane for many kinds of late-type stars.

E. W. Fick Observatory stellar radial velocity measurements. I - 1976-1984
Stellar radial velocity observations made with the large vacuumhigh-dispersion photoelectric radial velocity spectrometer at FickObservatory are reported. This includes nearly 2000 late-type starsobserved during 585 nights. Gradual modifications to this instrumentover its first eight years of operation have reduced the observationalerror for high-quality dip observations to + or - 0.8 km/s.

Uvby-Beta Photometry of Equatorial and Southern Bright Stars - Part Two
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...42..311H&db_key=AST

Photoelectric UBV photometry in some Milky Way fields
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&AS...11..365W&db_key=AST

La mesure des vitesses radiales au prisme objectif. XII. 5ème Liste de vitesses radiales déterminées au prisme objectif à vision directe
Not Available

Luminosity Function and Space Motions of G8-K1 Stars Derived from Spectroscopic Parallaxes.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1955ApJ...122..222H&db_key=AST

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Наблюдательные данные и астрометрия

Созвездие:Орион
Прямое восхождение:06h24m52.90s
Склонение:+16°03'25.0"
Видимая звёздная величина:6.33
Расстояние:118.064 парсек
Собственное движение RA:25.7
Собственное движение Dec:-42.1
B-T magnitude:7.687
V-T magnitude:6.459

Каталоги и обозначения:
Собственные имена
HD 1989HD 44867
TYCHO-2 2000TYC 1328-777-1
USNO-A2.0USNO-A2 1050-03510935
BSC 1991HR 2302
HIPHIP 30517

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