|CCD Speckle Observations of Binary Stars from the Southern Hemisphere. III. Differential Photometry|
Two hundred seventy-two magnitude difference measures of 135 double starsystems are presented. The results are derived from speckle observationsusing the Bessel V and R passbands and a fast readout CCD camera.Observations were taken at two 60 cm telescopes, namely the Helen SawyerHogg Telescope, formerly at Las Campanas, Chile, and the Lowell-TololoTelescope at the Cerro Tololo Inter-American Observatory, Chile. Thedata analysis method is presented and, in comparing the results to thoseof Hipparcos as well as to recent results using adaptive optics, we findvery good agreement. Overall, the measurement precision appears to bedependent on seeing and other factors but is generally in the range of0.10-0.15 mag for single observations under favorable observingconditions. In four cases, multiple observations in both V and R allowedfor the derivation of component V-R colors with uncertainties of 0.11mag or less. Spectral types are assigned and preliminary effectivetemperatures are estimated in these cases.
|Two-colour photometry for 9473 components of close Hipparcos double and multiple stars|
Using observations obtained with the Tycho instrument of the ESAHipparcos satellite, a two-colour photometry is produced for componentsof more than 7 000 Hipparcos double and multiple stars with angularseparations 0.1 to 2.5 arcsec. We publish 9473 components of 5173systems with separations above 0.3 arcsec. The majority of them did nothave Tycho photometry in the Hipparcos catalogue. The magnitudes arederived in the Tycho B_T and V_T passbands, similar to the Johnsonpassbands. Photometrically resolved components of the binaries withstatistically significant trigonometric parallaxes can be put on an HRdiagram, the majority of them for the first time. Based on observationsmade with the ESA Hipparcos satellite.
|Micrometer Measurements of Southern Double Stars made at the National Observatory of Llano del Hato, Venezuela|
This paper reports 151 micrometer measurements of 66 double starsobserved with the 65-cm refractor at the Venezuelan National Observatoryat Llano del Hato, Mérida, during February 1997 and February1998.
|The Age Range of Hyades Stars|
On the basis of canonical models, the age of Hyades supercluster stars,whether in the Hyades and Praesepe clusters or the noncluster field,ranges from (5-6) x 10^8 to 10^9 yr. The difference between the parallaxderived from the supercluster motion and that obtained from Hipparcosobservations has a dispersion only twice that of the mean dispersion ofthe individual Hipparcos values. The supercluster appears not to containred giants on the first ascent of the red giant branch, but onlyasymptotic giant branch (``clump'') stars. The masses obtained forindividual components of binary stars in the supercluster show adispersion of less than 10% when compared with model predictions.
|CCD Speckle Observations of Binary Stars From the Southern Hemisphere|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.2117H&db_key=AST
|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.
|ICCD speckle observations of binary stars. VIII - Measurements during 1989-1991 from the Cerro Tololo 4 M telescope|
One-thousand eighty-eight observations of 947 binary star systems,observed by means of speckle interferometry with the 4 m telescope onCerro Tololo, are presented. These measurements, made during the period1989-1991, comprise the second installment of results stemming from theexpansion of our speckle program to the southern hemisphere.
|Measurements of Double Stars in Merida, Venezuela|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1980A&AS...40..347V&db_key=AST
|HR 4453 - an anomalously bright UV source|
Crawford et al. (1979) reported that HR 4453 has an anomalously large UVflux in the 1350-1600 A band. This paper reports results of the UVspectrophotometry of HR 4453 obtained with the Copernicus satellite.Portions of the spectrum from 1120 to 2660 A were scanned, but nostellar signal was detected in any wavelength interval. This result isconsistent with both components of the binary being normal A2A stars. UVvariability or a source other than HR 4453 must be invoked to explainthe observations of Crawford et al.
|Far ultraviolet photometry of intermediate brightness stars from Apollo-Soyuz|
We present photoelectric photometry in the 1350-1600 A band of 52 starsof intermediate brightness, using data obtained in 1975 July with agrazing incidence telescope aboard the Apollo-Soyuz Test Project. Upperor lower limits on the brightness of 106 additional objects which werespatially blended with one or more companions were also obtained. Thedata sample consists of stars with V not greater than 7.5 and spectraltypes from O6 through A5. When corrected for interstellar extinction,the ultraviolet photometry on a two-color diagram agrees very well withthe predictions of the revised blanketed model atmospheres by Kurucz.Attention is also drawn to an anomalously UV-bright object which isprobably associated with HD 100493.
|Spectral classification from the ultraviolet line features of S2/68 spectra. III - Early A-type stars|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978A&AS...33...15C&db_key=AST
|Measures of southern visual double stars.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88...52H&db_key=AST
|Visual double stars measured at Las Campanas Observatory, Chile.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1975PASP...87..945H&db_key=AST
|Absolute luminosity calibration of Stroemgren's 'intermediate group'|
A relation defining the luminosity index for Stroemgren's (1966)intermediate group (A0 to A3 stars) in terms of absolute magnitude iscalibrated using a method based on the principle of maximum likelihood.This relation is also calibrated for the case when the 'a' index iscorrected for reddening. For both relations, calculations are made ofthe magnitude dispersion, the mean velocity components and correspondingdispersion, and the precision of each parameter. The results are shownto be in fairly good agreement with Stroemgren's (1966) values, and arelation incorporating the corrected 'a' index is proposed formain-sequence stars. The absolute magnitudes obtained with a relation ofthe present type are compared with those derived from trigonometricparallaxes and with those obtained by Eggen (1972).
|Four-colour and H BET photometry of some bright southern stars- II.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972MNRAS.160..155S&db_key=AST
|Intermediate-band photometry of RR LYR variables. I. Definition and characteristics of the system.|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1971MNRAS.154...79J&db_key=AST
|Stellar kinematics and evolution|
|The galactic force law K(z|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..139P&db_key=AST
|Stellar groups, VII. The structure of the Hyades group|
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1960MNRAS.120..540E&db_key=AST
|Double star measures-3rd series|