Оглавление
Изображения
Загрузить ваше изображение
DSS Images Other Images
Публикации по объекту
A catalogue of eclipsing variables
A new catalogue of 6330 eclipsing variable stars is presented. Thecatalogue was developed from the General Catalogue of Variable Stars(GCVS) and its textual remarks by including recently publishedinformation about classification of 843 systems and making correspondingcorrections of GCVS data. The catalogue1 represents thelargest list of eclipsing binaries classified from observations.
| New beta Cephei and SPB Stars Discovered in Hipparcos Photometry
We discuss 34 stars for which we detected new frequencies in HipparcosHp magnitudes. 13 of these stars are variables discovered in this paper.For 20 stars, we derive log T_eff and log g from Stromgren or Genevaphotometry.We classify one new beta Cep star, HIP 88352, two new beta Cep suspects,HIP 54753 and 88123, four new SPBs, HIP 1030, 39206, 46192 and 111147,and two SPB suspects, HIP 75787 and 98778. We find the last star to betriply-periodic and we show that the frequencies detected in Hpmagnitudes are present in the photoelectric observations of Hill etal(1976).Finally, we discover the hottest variable of the SPB type, namely, HIP1030.
| V505 Mon - An early-type binary with a disk
New spectra of the eclipsing binary V505 Mon (usually classified as B5Ib) were obtained in the optical and UV regions. Only spectral lines ofone component are visible, with K = 93 km s-1. According toarguments based on the extent of the disk the mass ratio might be about0.30. The star with the visible spectral lines would then have a mass of2.3, the other component of 7.7 Msun, i.e. their supergiantnature can be ruled out. The distance to the system appears to be about1 kpc. Together with published photometric data, the spectroscopyprovides clear evidence for the presence of a disk around the secondarycomponent. The profiles of the C II 1335/6 doublet lines are used toderive the rotational velocity of the disk. The structure of the diskcan be characterized by a central ionized zone surrounded by neutralouter parts. Additional matter of cloudy nature has to be present, andboth components are embedded in an extended atmosphere. Abundance ofcarbon was found to be very low. Similarity with some othernon-eclipsing binaries is discussed. Based on observations collected atthe European Southern Observatory, La Silla, Chile, and at theGerman-Spanish Observatory, Calar Alto, Spain.
| A Search for High-Velocity Be Stars
We present an analysis of the kinematics of Be stars based uponHipparcos proper motions and published radial velocities. We findapproximately 23 of the 344 stars in our sample have peculiar spacemotions greater than 40 km s-1 and up to 102 kms-1. We argue that these high-velocity stars are the resultof either a supernova that disrupted a binary or ejection by closeencounters of binaries in young clusters. Be stars spun up by binarymass transfer will appear as high-velocity objects if there wassignificant mass loss during the supernova explosion of the initiallymore massive star, but the generally moderate peculiar velocities of BeX-ray binaries indicate that the progenitors lose most of their massprior to the supernova (in accordance with model predictions). Binaryformation models for Be stars predict that most systems bypass thesupernova stage (and do not receive runaway velocities) to createultimately Be+white dwarf binaries. The fraction of Be stars spun up bybinary mass transfer remains unknown, since the post-mass transfercompanions are difficult to detect.
| Catalogue of H-alpha emission stars in the Northern Milky Way
The ``Catalogue of Stars in the Northern Milky Way Having H-alpha inEmission" appears in Abhandlungen aus der Hamburger Sternwarte, Band XIin the year 1997. It contains 4174 stars, range {32degr <= l() II< 214degr , -10degr < b() II < +10degr } having the Hαline in emission. HBH stars and stars of further 99 lists taken from theliterature till the end of 1994 were included in the catalogue. We givethe cross-identification of stars from all lists used. The catalogue isalso available in the Centre de Données, Strasbourg ftp130.79.128.5 or http://cdsweb.u-strasbg.fr and at the HamburgObservatory via internet.
| Catalogue of stars in the northern Milky Way having H-alpha in emission
Not Available
| 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.
| The List of the Nearest and Bright Eclipsing Binaries from the HIPPARCOS Program
Not Available
| Observations of interstellar diffuse absorption band at 4430 A
Observations of the interstellar diffuse absorption band at 4430 A for800 O and B stars in Neckel's (1967) catalog are being carried out, and482 spectra obtained up to September 1983 have been reduced. It isconfirmed that the strength of the interstellar diffuse absorption bandat 4430 A does not simply relate to the abundance of interstellar grainson the line of sight. The relation between the color excess E(B-V) andthe equivalent width of the band to the direction of l = 130-140 deg andb = -5 to +5 deg shows that some parameter(s) other than E(B-V) is (are)needed to understand the cause of this band.
| 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.
| The ellipsoidal variable stars
An annotated bibliography is presented for the ellipsoidal variableclass of noneclipsing close binaries, and a method is furnished for theanalysis of the light curves and spectroscopic data to determine thephysical parameters of such systems. Attention is given to confirmedellipsoidal variables, as well as suspected and rejected ones, and tothe characteristics of theoretical ellipsoidal light curves.
| Five suspected Beta Cephei stars revisited
The following suspected Beta Cephei stars have been observedphotometrically or rediscussed: HDE 232999, HD 34626, 43818, 43837 and190467. The first two stars have been found to be Be stars and, likemany such stars, they vary in brightness on a time scale of hours. Thelast three stars are bright giants or supergiants and, like most suchstars, they vary in brightness on a time scale of days. The period andamplitude of the photometric variability of these five stars can thus beunderstood in the general context of stellar variability, even thoughnone of them appears to be a classical Beta Cephei star.
| Distribution of OB stars and absorbing matter in the region around P CYG
The results of spectrophotometric observations of 277 OB stars in a 7 x7-deg region around P Cyg, obtained in 8-sec, 45-sec, and 8-minexposures on ORWO ZU-21 plates with a 4-deg 272-A/mm-dispersionobjective prism on the 40-in. Schmidt telescope at BiurakanAstrophysical Observatory on October 14-19, 1979, are presented intables and graphs and characterized. Data reported include 400-480-nmabsolute spectrophotometric gradients, color excesses, and distances. Itis found that concentrations of OB stars with associated absorbingmatter exist toward the associations Cyg OB9 (two concentrations at 800and 1800 pc), Cyg OB3 (three concentrations at 1.4, 2.5, and 3.7 kpc),OB1 (at 1.6 kpc), Cyg OB8 (at 1.5 kpc), and over the entire observedregion at a distance of about 500 pc.
| Catalogue of Eclipsing and Spectroscopic Binary Stars in the Regions of Open Clusters
Not Available
| New UBVRI photometry for 900 supergiants
A description is presented of the results obtained in connection with asystematic program of supergiant photometry on the Johnson UBVRI system.During the eight years after the start of the program, almost 1000 starshave been observed, about 400 three or more times each. The originalselection of stars used the spectral type catalog of Jaschek et al.(1964) to choose supergiants. Since observations were possible from bothChile and Canada, no declination limits were imposed, and no particularselection criteria were imposed other than to eliminate carbon stars.These are so red as to require enormous extrapolations of thetransformation equations.
| A search for weak galactic binary X-ray sources
Observations undertaken to investigate the relation of mass transferrates to X-ray luminosities in accreting binary X-ray sources in theGalaxy are discussed. Einstein Observatory Imaging Proportional Counterobservations were made of 23 binary systems selected as possiblycontaining a compact object. Only three of the original 17 targetobjects were detected as sources, plus two more among the six also foundto be within Einstein IPC fields. None of the sources detected, however,shows evidence for the presence of a compact component. It is concludedthat there are few, if any, binaries in which a compact star is in a lowX-ray state, and that the known hard X-ray binaries constitute theentire galactic population of such objects.
| Studies of early-type variable stars. I - The ellipsoidal and Beta Cephei variable HD 149881 /V 600 Her/
Fifty years of spectroscopic data are used to determine an orbit for theellipsoidal variable HD 149881 (V 600 Her). It is shown that this staris actually a spectroscopic binary with a period of 5.20 days andvelocity variations characteristic of Beta Cephei variables. The lightcurve and orbital data are combined to derive the orbital and physicalparameters of the system. For an assumed primary mass of 15 solarmasses, the following parameters are obtained: an orbital inclination of35 deg, a surface gravity of log g = 3.26, a primary radius of 15 solarradii, a secondary mass of two solar masses, a bolometric magnitude (forthe whole system) of -8.1, an absolute visual magnitude of -5.4, and aspectral type (for the primary) of B0.5 III. The evolutionary state ofBeta Cephei stars is reviewed, noting that such stars are probably nearthe end of hydrogen exhaustion.
| Observations of southern emission-line stars
A catalog of 1929 stars showing H-alpha emission on photographic platesis presented which covers the entire southern sky south of declination-25 deg to a red limiting magnitude of about 11.0. The catalog providesprevious designations of known emission-line stars equatorial (1900) andgalactic coordinates, visual and photographic magnitudes, H-alphaemission parameters, spectral types, and notes on unusual spectralfeatures. The objects listed include 16 M stars, 25 S stars, 37 carbonstars, 20 symbiotic stars, 40 confirmed or suspected T Tauri stars, 16novae, 14 planetary nebulae, 11 P Cygni stars, 9 Bep stars, 87 confirmedor suspected Wolf-Rayet stars, and 26 'peculiar' stars. Two new Tassociations are discovered, one in Lupus and one in Chamaeleon. Objectswith variations in continuum or H-alpha intensity are noted, and thedistribution by spectral type is analyzed. It is found that the skydistribution of these emission-line stars shows significantconcentrations in the region of the small Sagittarius cloud and in theCarina region.
| Photoelectric measures of variable stars observed at MT. Kobau (1970-73).
Not Available
| Photometry in the Cygnus X-1 field
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974A&A....30..467M&db_key=AST
| 58th Name-List of Variable Stars
Not Available
| A photometric study of some early B stars whose spectral lines vary in sharpness.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75..818P&db_key=AST
| Catalogue d'etoiles O et B.
Not Available
| Photoelectric 4430 A observations of 506 O, B and A stars.
Not Available
| Photoelectric observations of the intensity of the 4430 band in 147 O, B, and A stars in the Northern Milky Way.
Not Available
| Photoelectric observations of the intensity of the 4430 band in 147 O,B, and A stars in the Northern Milky Way
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
| Catalogue of stellar spectra classified in the Morgan-Keenan system
Not Available
| Photoelectric measures of the 4430 A diffuse interstellar band
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963MNRAS.125..141W&db_key=AST
|
Добавить новую статью
Внешние ссылки
- - Внешних ссылок не найдено -
Добавить внешнюю ссылку
Группы:
|
Наблюдательные данные и астрометрия
| Созвездие: | Лебедь |
| Прямое восхождение: | 20h03m41.60s |
| Склонение: | +36°25'32.2" |
| Видимая звёздная величина: | 8.188 |
| Расстояние: | 769.231 парсек |
| Собственное движение RA: | -0.5 |
| Собственное движение Dec: | -6.2 |
| B-T magnitude: | 8.317 |
| V-T magnitude: | 8.199 |
Каталоги и обозначения:
|
