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CHARM2: An updated Catalog of High Angular Resolution Measurements
We present an update of the Catalog of High Angular ResolutionMeasurements (CHARM, Richichi & Percheron \cite{CHARM}, A&A,386, 492), which includes results available until July 2004. CHARM2 is acompilation of direct measurements by high angular resolution methods,as well as indirect estimates of stellar diameters. Its main goal is toprovide a reference list of sources which can be used for calibrationand verification observations with long-baseline optical and near-IRinterferometers. Single and binary stars are included, as are complexobjects from circumstellar shells to extragalactic sources. The presentupdate provides an increase of almost a factor of two over the previousedition. Additionally, it includes several corrections and improvements,as well as a cross-check with the valuable public release observationsof the ESO Very Large Telescope Interferometer (VLTI). A total of 8231entries for 3238 unique sources are now present in CHARM2. Thisrepresents an increase of a factor of 3.4 and 2.0, respectively, overthe contents of the previous version of CHARM.The catalog is only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/431/773
| CHARM: A Catalog of High Angular Resolution Measurements
The Catalog of High Angular Resolution Measurements (CHARM) includesmost of the measurements obtained by the techniques of lunaroccultations and long-baseline interferometry at visual and infraredwavelengths, which have appeared in the literature or have otherwisebeen made public until mid-2001. A total of 2432 measurements of 1625sources are included, along with extensive auxiliary information. Inparticular, visual and infrared photometry is included for almost allthe sources. This has been partly extracted from currently availablecatalogs, and partly obtained specifically for CHARM. The main aim is toprovide a compilation of sources which could be used as calibrators orfor science verification purposes by the new generation of largeground-based facilities such as the ESO Very Large Interferometer andthe Keck Interferometer. The Catalog is available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/386/492, and from theauthors on CD-Rom.
| New periodic variables from the Hipparcos epoch photometry
Two selection statistics are used to extract new candidate periodicvariables from the epoch photometry of the Hipparcos catalogue. Theprimary selection criterion is a signal-to-noise ratio. The dependenceof this statistic on the number of observations is calibrated usingabout 30000 randomly permuted Hipparcos data sets. A significance levelof 0.1 per cent is used to extract a first batch of candidate variables.The second criterion requires that the optimal frequency be unaffectedif the data are de-trended by low-order polynomials. We find 2675 newcandidate periodic variables, of which the majority (2082) are from theHipparcos`unsolved' variables. Potential problems with theinterpretation of the data (e.g. aliasing) are discussed.
| 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
| On the Variability of K5-M Stars
I investigate the Hipparcos Satellite photometry of K5-M stars to seethe pattern of activity of these stars. A few stars for which furtherstudy is desirable are identified.
| Classification and Identification of IRAS Sources with Low-Resolution Spectra
IRAS low-resolution spectra were extracted for 11,224 IRAS sources.These spectra were classified into astrophysical classes, based on thepresence of emission and absorption features and on the shape of thecontinuum. Counterparts of these IRAS sources in existing optical andinfrared catalogs are identified, and their optical spectral types arelisted if they are known. The correlations between thephotospheric/optical and circumstellar/infrared classification arediscussed.
| 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.
| Lunar Occultations of Southern Near Infrared Stellar Sources
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1992A&A...254..149R&db_key=AST
| Einstein Observatory magnitude-limited X-ray survey of late-type giant and supergiant stars
Results are presented of an extensive X-ray survey of 380 giant andsupergiant stars of spectral types from F to M, carried out with theEinstein Observatory. It was found that the observed F giants orsubgiants (slightly evolved stars with a mass M less than about 2 solarmasses) are X-ray emitters at the same level of main-sequence stars ofsimilar spectral type. The G giants show a range of emissions more than3 orders of magnitude wide; some single G giants exist with X-rayluminosities comparable to RS CVn systems, while some nearby large Ggiants have upper limits on the X-ray emission below typical solarvalues. The K giants have an observed X-ray emission level significantlylower than F and F giants. None of the 29 M giants were detected, exceptfor one spectroscopic binary.
| Lunar occultations at La Silla
The first ever lunar occultations at La Silla are reported. The angulardiameter of SAO 185573 was measured for the first time with very highaccuracy. The occultation of Antares was also recorded with very goodSNR, allowing a detailed study of the outer layers of this supergiant.
| Lunar occultations of IRAS point sources, 1986-1990
A complete listing is given for objects in the IRAS Point Source Catalogwhich will be occulted by the moon over the course of 1986-1990. A totalof 14,148 ASCII card images is encompassed by the complete listing ofobjects having geocentric events during this period. The resultscontained in this complete listing are illustrated in two of the presenttables for the brightest objects at 12 and 100 micron wavelengths.
| A catalogue of M type stars
The catalogue of 2116 M type and 17 other type stars, carbon stars, Stype stars, and Wolf-Rayet stars, is prepared for the galactic centerregion between 1 = 351 and 1 deg, and between b = -2 and +2 deg. Thecompleteness of the survey down to the limiting magnitude for detectableM type stars is about 90 percent for early (M2-M4) subclasses, and 99percent for intermediate (M5-M6) and late (M6.5-M8) subclasses. Thespectral classification of the M type stars detected is made accordingto the Case system. The accuracy of the positional data for each star iswithin 1.5 sec of arc. Apparent magnitudes in the I and R bands arepresented with an accuracy of + or - 0.3 mag. The limiting magnitude isabout 12.0 in the I band for early M type subclasses and about 12.5 forboth intermediate and late type subclasses. It is suggested that thecatalogue is useful for statistical studies of the galactic structureand further studies on the properties of the stars.
| A photometric catalogue of stars in the direction of the bright cloud B in Sagittarius
The present catalog includes photometric data on stars in a 5.5 deg x5.5 deg area in the direction of the bright cloud B in Sagittarius,centered at l equals 357.7 deg, b equals plus 5.6 deg. V magnitudes andB-V and U-B colors are reported for nearly all HD and HDE stars in thefield and also for a number of interesting stars (402 stars), 21 propermotion stars, and 45 stars in a 15 arcmin radius circular regioncentered on the galactic cluster Trumpler 26 (Tr 26). Furthermore,photographic B, V, R, and IR magnitudes are listed for 274 stars in thefield of Tr 26. These data will be used for further studies ofinterstellar absorption in the Galaxy's central direction in relation tospecific objects (red variable stars, star clusters, diffuse objects).
| Three colour observations of southern red variable giant stars
UBV observations have been made of southern red variables of varioustypes over a period of two years. Accurate light curves of about 35variables have been obtained; in many cases the observations coveredmore than one cycle. It appears that the M-type SRb and Lb variablesdefine a curved strip in the (B-V)-(U-B) plane. The mean (U-B) of thevariable stars is about 0.5 mag bluer than the (U-B) of the nonvariableK-type giants. The red variables may be divided into different groups:the carbon stars and the M-type variables, of which the M-type stars areagain to be divided into three groups on the basis of their colorvariations and consequently their loops in the two-color plane.
| Six-color photometry of stars. VIII. The colors of 409 stars of different spectral types
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1956ApJ...123..440S&db_key=AST
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | נושא הנחש |
| התרוממות ימנית: | 17h38m11.99s |
| סירוב: | -28°02'48.3" |
| גודל גלוי: | 6.899 |
| מרחק: | 487.805 פארסק |
| תנועה נכונה: | -6.6 |
| תנועה נכונה: | -14.4 |
| B-T magnitude: | 9.397 |
| V-T magnitude: | 7.106 |
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