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HD 36895


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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

A WIYN Lithium Survey for Young Stars in the λ Orionis Star-Forming Region
We have found 72 pre-main-sequence (PMS) stars near the center of theλ Orionis star-forming region by spectroscopically testing amagnitude-limited sample for the presence of lithium λ6708absorption, a diagnostic of youth. All of these stars show large lithiumequivalent widths and radial velocities consistent with Orionmembership, but only two were discovered previously via Hα orX-ray surveys. Comparison with PMS evolutionary tracks show that thelow-mass star formation did not begin prior to the initiation ofhigh-mass star formation 5-7 Myr ago. However, the subsequent detailedstar formation history is model dependent. Baraffe et al. isochronesimply that high- and low-mass stars began to form together 5-7 Myr ago,with the low-mass stellar formation ceasing abruptly 1 Myr ago. On theother hand, D'Antona & Mazzitelli isochrones indicate a narrowspread of PMS ages, which suggests a burst of low-mass star formation1-2 Myr ago. Furthermore, kinematic arguments require that the parentmolecular cloud gravitationally bound the stars together until recently,but at present the requisite gas mass is not visible. This leads us toconjecture that both the high- and low-mass stars were in a tightlybound cluster until a supernova blast about 1 Myr ago disrupted theparent cloud. This supernova also impacted on the PMS formation processby either (1) ceasing formation through removal of the gas supply or (2)triggering star births via cloud compression, depending on choice ofstellar evolution models. Finally, we find that despite their youth,only four of the 72 PMS stars have T Tauri-like Hα emission,suggesting the absence of accretion disks. We conjecture that this maybe the result of photoevaporation of the disks while the low-mass starswere in much closer proximity to the OB stars prior to becominggravitationally unbound.

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.

An Einstein Observatory SAO-based catalog of B-type stars
About 4000 X-ray images obtained with the Einstein Observatory are usedto measure the 0.16-4.0 keV emission from 1545 B-type SAO stars fallingin the about 10 percent of the sky surveyed with the IPC. Seventy-fourdetected X-ray sources with B-type stars are identified, and it isestimated that no more than 15 can be misidentified. Upper limits to theX-ray emission of the remaining stars are presented. In addition tosummarizing the X-ray measurements and giving other relevant opticaldata, the present extensive catalog discusses the reduction process andanalyzes selection effects associated with both SAO catalog completenessand IPC target selection procedures. It is concluded that X-rayemission, at the level of Lx not less than 10 exp 30 ergs/s, is quitecommon in B stars of early spectral types (B0-B3), regardless ofluminosity class, but that emission, at the same level, becomes lesscommon, or nonexistent, in later B-type stars.

Dust ring around Lambda Orionis
Sky maps of a 12 deg x 12 deg region obtained by IRAS reveal a dust ringwhich has a diameter of about 9 deg and is centered on the H II region S264 and its exciting star, Lambda Orionis. The 60/100 micron colortemperature in the ring with an assumed dust emissivity law nu exp 1.5is on average 25 K. The luminosity in the IRAS wavelength range and thetotal far-infrared luminosity for the ring are 38,000 and 63,000 solarluminosities, respectively. The radiation field responsible for theheating of dust in the ring contains an enhanced UV component with anenergy density 2 to 3 times as large as that of the general interstellarradiation field. This enhancement of the UV component is ascribed to theO star Lambda Ori and several other early B stars. A careful analysis ofthe energetics of the ring shows that its total infrared luminosity canbe explained by the energy supply from the Lambda Ori OB association, HD34989 and the interstellar radiation field.

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.

Observed and computed spectral flux distribution of non-supergiant O9-G8 stars. III - Determination of T(eff) for the stars in the Breger Catalogue
The effective temperatures and angular diameters of nonsupergiant O9-G8stars are determined from visible spectrophotometry. The results, whichrefer to 302 stars included in the Breger Catalogue, are derived fromthe comparison between the observed flux distributions and thepredictions of Kurucz's models (1979). The uncertainties to be expectedin individual results are discussed; their sizes are of the order of 5percent in effective temperature and 10 percent in angular diameter.

A search for ring nebulae around Of stars
The Palomar Sky Survey prints have been used in a search for ringnebulae produced by the stellar wind, which involved the examination ofthe fields around 72 types of Of stars. It is found that for about halfof these stars, such ring nebulae as might exist would probably beunobservable because of the heavy absorption of bright H-alphabackground emission. Nevertheless, the H II regions surrounding 14 ofthe Of stars are found to exhibit ringlike structure.

Catalog of spectrophotometric scans of stars.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...32....7B&db_key=AST

Equivalent widths and rotational velocities of southern early-type stars
Not Available

On the kinematical and spatial coincidence of optical and radio spiral arms in our galaxy.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1973A&A....24..393M&db_key=AST

A Test for Relative Motions of Gas and Young Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972PASP...84..273M&db_key=AST

Some Spectroscopic Characteristics of the OB Stars: an Investigation of the Space Distribution of Certain OB Stars and the Reference Frame of the Classification
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJS...23..257W&db_key=AST

Energy Distributions and Spectra of Orion B Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971ApJ...169..529S&db_key=AST

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

Distances of southern B-stars and galactic structure from Hγ-luminosities
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1961MNRAS.123..191B&db_key=AST

A Catalogue of H II Regions.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJS....4..257S&db_key=AST

The Light-Variability of Early B Giants.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1959ApJ...130..577L&db_key=AST

Study on Galactic Rotation Based on Radial Velocities, of OB Stars and O-Associations
Not Available

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Gözlemler ve gökölçümü verileri

Takýmyýldýz:Avci
Sað Açýklýk:05h35m12.80s
Yükselim:+09°36'47.7"
Görünürdeki Parlaklýk:6.706
Uzaklýk:425.532 parsek
özdevim Sað Açýklýk:-0.3
özdevim Yükselim:-2.5
B-T magnitude:6.544
V-T magnitude:6.693

Kataloglar ve belirtme:
Özgün isimleri   (Edit)
HD 1989HD 36895
TYCHO-2 2000TYC 705-74-1
USNO-A2.0USNO-A2 0975-01744195
HIPHIP 26212

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