Preparing the COROT space mission: Incidence and characterisation of pulsation in the lower instability strip
By pursuing the goal to find new variables in the COROT field-of-view wecharacterised a sample of stars located in the lower part of theinstability strip. Our sample is composed of stars belonging to the diskpopulation in the solar neighbourhood. We found that 23% of the starsdisplay multiperiodic light variability up to a few mmag in amplitude,i.e., easily detectable on a single night of photometry. uvbybetaphotometry fixed most of the variables in the middle of the instabilitystrip and high-resolution spectroscopy established that they have vsin i>100 km s-1. An analysis of the Rodríguez &Breger (\cite{Rodr01}) sample (delta Sct stars in the whole Galaxy)shows slightly different features, i.e., most delta Sct stars have a0.05-mag redder (b-y)0 index and lower vsin i values.Additional investigation in the open cluster NGC 6633 confirms the sameincidence of variability, i.e., around 20%. The wide variety ofpulsational behaviours of delta Sct stars (including unusual objectssuch as a variable beyond the blue edge or a rapidly rotatinghigh-amplitude pulsator) makes them very powerful asteroseismic tools tobe used by COROT. Being quite common among bright stars, delta Sctstars are suitable targets for optical observations from space.Based on observations collected at the S. Pedro Martír, SierraNevada, La Silla, Haute-Provence, South African and Roque de LosMuchachos observatories.
|
Kinematics of Hipparcos Visual Binaries. II. Stars with Ground-Based Orbital Solutions
This paper continues kinematical investigations of the Hipparcos visualbinaries with known orbits. A sample, consisting of 804 binary systemswith orbital elements determined from ground-based observations, isselected. The mean relative error of their parallaxes is about 12% andthe mean relative error of proper motions is about 4%. However, even 41%of the sample stars lack radial velocity measurements. The computedGalactic velocity components and other kinematical parameters are usedto divide the stars with known radial velocities into kinematical agegroups. The majority (92%) of binaries from the sample are thin diskstars, 7.6% have thick disk kinematics and only two binaries have halokinematics. Among them, the long-period variable Mira Ceti has a verydiscordant {Hipparcos} and ground-based parallax values. From the wholesample, 60 stars are ascribed to the thick disk and halo population.There is an urgent need to increase the number of the identified halobinaries with known orbits and substantially improve the situation withradial velocity data for stars with known orbits.
|
Micrometer measurements of double stars made at the Côte D'Azur and Calar Alto observatories
We report 312 micrometer measurements of 155 visual double stars madewith the 50 cm refractor at the Côte D'Azur observatory (Nice,France) and with the 152 cm telescope at Calar Alto observatory(Almería, Spain).
|
Speckle Interferometry at the US Naval Observatory. III.
Position angles and separations resulting from 2578 speckleinterferometric observations of 590 binary stars are tabulated. This isthe third in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, andcovers the period from 1995 June through 1996 December. Program starsrange in separation from 0.2" to 4.3", with a limiting magnitude ofV=11. Random errors are estimated to be 17.0 mas in separation and0.56d/rho in position angle, where rho is the separation in arcseconds.These are the first results acquired using an improved intensified CCDdetector. The new detector, in concert with an intensity-filteringtechnique applied in software, has permitted a 1 mag increase in dynamicrange, to 3.5 mag, for pairs separated by about 2". The instrumentationand calibration are briefly described, with an emphasis on thecharacteristics of the new detector. The software filter used toincrease the dynamic range is also described.
|
Speckle Interferometry at the US Naval Observatory. II.
Position angles and separations resulting from 2406 speckleinterferometric observations of 547 binary stars are tabulated. This isthe second in a series of papers presenting measures obtained using the66 cm refractor at the US Naval Observatory in Washington, DC, with anintensified CCD detector. Program stars range in separation from 0.2" to3.8", with Deltam<=2.5 mag and a limiting magnitude of V=10.0. Theobservation epochs run from 1993 January through 1995 August. Randomerrors are estimated to be 14 mas in separation and 0.52d/rho inposition angle, where rho is the separation in arcseconds. Theinstrumentation and calibration are briefly described. Aspects of thedata analysis related to the avoidance of systematic errors are alsodiscussed.
|
Radial velocities. Measurements of 2800 B2-F5 stars for HIPPARCOS
Radial velocities have been determined for a sample of 2930 B2-F5 stars,95% observed by the Hipparcos satellite in the north hemisphere and 80%without reliable radial velocity up to now. Observations were obtainedat the Observatoire de Haute Provence with a dispersion of 80Ä,mm(-1) with the aim of studying stellar and galactic dynamics.Radial velocities have been measured by correlation with templates ofthe same spectral class. The mean obtained precision is 3.0 km s(-1)with three observations. A new MK spectral classification is estimatedfor all stars. Based on observations made at the Haute ProvenceObservatory, France and on data from The Hipparcos Catalogue, ESA.Tables 4, 5 and 6 are only available in electronic form at the CDS viaanonymous ftp to cdsarc.u-strasbg.fr or viahttp://cdsweb.u-strasbg.fr/Abstract.htm
|
Observations of Double Stars. XVIII.
Micrometer observations of 1350 pairs in 1995-1997 are listed.
|
Micrometer measurements of double stars from the Spanish observatories at Calar Alto and Santiago de Compostela.
This paper reports 458 micrometer observations of visual double starsmade with the 152 cm. telescope at Calar Alto Observatory (Almeria,Spain) and with the 35 cm. telescope at Ramon Maria Aller Observatory(Santiago de Compostela, Spain). Tables 1 and 2 only available inelectronic form at CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html
|
Micrometer measurements of visual double stars made at the Cote d'Azur Observatory.
Not Available
|
ICCD Speckle Observations of Binary Stars. XVII. Measurements During 1993-1995 From the Mount Wilson 2.5-M Telescope.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.1639H&db_key=AST
|
ICCD Speckle Observations of Binary Stars. XVI. Measurements During 1982-1989 from the Perkins 1.8-M Telescope.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1997AJ....114.1623F&db_key=AST
|
Micrometer measurements of visual double stars made at the Spanish observatories at Calar Alto and Fabra
The study presents 184-micrometer measurements of 100 double starsobserved with the 152-cm telescope at Calar Alto (Almeria, Spain) andthe 38-cm refractor at Fabra Observatory (Barcelona, Spain). The epoch,observed position angle, angular distance between components, number ofnights on which the star was observed, and an indication of the observerare given. Orbits were calculated for almost all the observed stars.
|
Observations of double stars and new pairs. XIV
Results of a continuing survey of visual double stars are presented,including 4880 measurements made from February 1987 to November 1989.The positions in WDS format and Durchmusterung numbers are given for 194pairs first reported here. Micrometer measurements of 1142 doubles madewith the Swarthmore 61 cm refractor are presented. Magnitudes areestimated for some of the objects. Plate measurements, plateorientations, position angles, number of nights, and measured exposuresare given. Visual observations of 342 pairs obtained in May 1989 atCerro Tololo, mostly with the 1.0 m reflector, are reported.
|
Measurements of binaries made with the 152-cm telescope at Calar Alto
A total of 143 micrometer measurements are presented for 58 double starsobserved with the 152-cm telescope of the National AstronomicalObservatory at Calar Alto. This is the first published list ofobservations of this kind made with this telescope.
|
Micrometer observations of double stars and new pairs. XIII
From a program of double star observations which emphasizes orbital,neglected, and newly discovered pairs, results obtained from October1984 to January 1987 are presented. A total of 3030 visual and 550photographic measures are listed. The positions in WDS format andDurchmusterung numbers are shown for 117 pairs for which firstobservations appear in this paper. Magnitudes are estimated for some ofthe objects.
|
Micrometer Measurements of Visual Double Stars - Part Three -
Not Available
|
ICCD speckle observations of binary stars. II - Measurements during 1982-1985 from the Kitt Peak 4 M telescope
This paper represents the continuation of a systematic program of binarystar speckle interferometry initiated at the 4 m telescope on Kitt Peakin late 1975. Between 1975 and 1981, the observations were obtained witha photographic speckle camera, the data from which were reduced byoptical analog methods. In mid-1982, a new speckle camera employing anintensified charge-coupled device as the detector continued the programand necessitated the development of new digital procedures for reducingand analyzing speckle data. The camera and the data-processingtechniques are described herein. This paper presents 2780 newmeasurements of 1012 binary and multiple star systems, including thefirst direct resolution of 64 systems, for the interval 1982 through1985.
|
Visual multiples. VIII - 1000 MK types
A total of 1000 new classifications are given for stars brighter than B= 8.0 mag in the Aitken double star catalog. The classificationssupplement 865 classifications obtained in 1981 and 1984. Among thenewly discovered stars are 12 new Ap stars, eight Lambda Bootis stars,one Ba II star, and 60 Am stars. A detailed list of the newclassifications is given.
|
Speckle interferometric measurements of binary stars. VII
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1982ApJS...49..267M&db_key=AST
|
Double star measures at Lick Observatory, Mount Hamilton, California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1978PASP...90..465H&db_key=AST
|
Double star measures at Lick Observatory Mount Hamilton California.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976PASP...88..325H&db_key=AST
|
Double Star Measures at Lick Observatory, Mount Hamilton, California
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974PASP...86..902H&db_key=AST
|
Micrometric Measures of Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..413V&db_key=AST
|
On the inclination of rotation axes in visual binaries.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJ...190..331W&db_key=AST
|
Mesures d'étoiles doubles faites à l'équatorial de 38 CM de l'Observatoire de Paris
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&AS....6..147B&db_key=AST
|
Mesures d'étoiles doubles à Meudon (2^éme série)
Not Available
|
MK Classification of 142 Visual Binaries
Not Available
|
Mesures d'etoiles doubles faites AU 38cm de l'Observatoire de Paris.
Not Available
|
Mikrometermessungen von Doppelsternen. V
Not Available
|
Masses, luminosities, colors, and space motions of 228 visual binaries
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1965AJ.....70...19E&db_key=AST
|
