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HD 107159


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Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.

The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars
This is the first in a series of two papers that address the problem ofthe physical nature of luminosity classification in the late A-, F-, andearly G-type stars. In this paper, we present precise spectralclassifications of 372 stars on the MK system. For those stars in theset with Strömgren uvbyβ photometry, we derive reddenings andpresent a calibration of MK temperature types in terms of the intrinsicStrömgren (b-y)0 index. We also examine the relationshipbetween the luminosity class and the Strömgren c1 index,which measures the Balmer jump. The second paper will address thederivation of the physical parameters of these stars, and therelationships between these physical parameters and the luminosityclass. Stars classified in this paper include one new λ Bootisstar and 10 of the F- and G-type dwarfs with recently discoveredplanets.

The FIRST Unbiased Survey for Radio Stars
Comparison of the VLA FIRST survey with various catalogs of bright starsallows an examination of the prevalence of stellar radio emissionindependent of optical selection criteria. This FIRST unbiased surveyfor radio stars covers nearly 5000 deg^2 of the northern sky to a fluxdensity limit of 0.7 mJy at 20 cm. Using astrometric catalogs thatinclude proper-motion information, we have detected 26 stellar radiosources, doubling the number of such objects previously known in thisregion of high-latitude sky. We also show that, in the absence of goodproper motions, even the 1" precision of the FIRST positions isinsufficient to avoid crippling chance coincidence rates. We calculatethe fraction of radio detections as a function of stellar magnitude andshow that, when proper motions from the Guide Star Catalog II becomeavailable, the number of stellar radio source detections should increasefourfold.

An astrometric catalogue for the area of Coma Berenices
A catalogue of stellar positions and proper motions down to the 14thphotographic magnitude in the area of the open cluster in Coma Berenicesis compiled from data of 12 different sources. The accuracy of theproper motion data is comparable to that of the Hipparcos Catalogue. Thecatalogue Table 5 is 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

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.

Photoelectric photometry of bright stars in the vicinity of the North Galactic Pole
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Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Four - a Catalogue of Uvbyr Photometry and Derived Quantities
Not Available

Further Studies of A-Stars and F-Stars in the Region of the North Galactic Pole - Part Three - a Catalogue of Star Names and Positions
Not Available

Studies of A and F stars in the region of the North galactic pole-I. Radial velocities and MK Classifications
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A finding-list of stars of spectral type F2 and earlier in a north galactic pole region.
Not Available

La mesure des vitesses radiales au prisme objectif. V. -Discussion des résultats pour une cinquantaine d'étoiles de la Chevelure de Bérénice
Not Available

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Osservazione e dati astrometrici

Costellazione:Chioma di Berenice
Ascensione retta:12h19m15.94s
Declinazione:+25°03'36.9"
Magnitudine apparente:7.774
Distanza:165.289 parsec
Moto proprio RA:27.9
Moto proprio Dec:-16.9
B-T magnitude:8.14
V-T magnitude:7.805

Cataloghi e designazioni:
Nomi esatti   (Edit)
HD 1989HD 107159
TYCHO-2 2000TYC 1989-601-1
USNO-A2.0USNO-A2 1125-06490750
HIPHIP 60083

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