Binary Star Speckle Measurements with the 1.52-m telescope at Calar Alto
We present binary star interferometric measurements carried out on 2001July and 2004 February with our ICCD speckle camera attached to the1.52-m telescope of the Observatorio Astronómico Nacional atCalar Alto (Almería, Spain). Data comprise 120 observations of 87systems with the measured angular separations ranging from 0''.102 to6''.076. They are used to improve the orbital elements for STT 170 andSTF 1670 AB.
|
Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters
The availability of the Hipparcos Catalogue has triggered many kinematicand dynamical studies of the solar neighbourhood. Nevertheless, thosestudies generally lacked the third component of the space velocities,i.e., the radial velocities. This work presents the kinematic analysisof 5952 K and 739 M giants in the solar neighbourhood which includes forthe first time radial velocity data from a large survey performed withthe CORAVEL spectrovelocimeter. It also uses proper motions from theTycho-2 catalogue, which are expected to be more accurate than theHipparcos ones. An important by-product of this study is the observedfraction of only 5.7% of spectroscopic binaries among M giants ascompared to 13.7% for K giants. After excluding the binaries for whichno center-of-mass velocity could be estimated, 5311 K and 719 M giantsremain in the final sample. The UV-plane constructed from these datafor the stars with precise parallaxes (σπ/π≤20%) reveals a rich small-scale structure, with several clumpscorresponding to the Hercules stream, the Sirius moving group, and theHyades and Pleiades superclusters. A maximum-likelihood method, based ona Bayesian approach, has been applied to the data, in order to make fulluse of all the available stars (not only those with precise parallaxes)and to derive the kinematic properties of these subgroups. Isochrones inthe Hertzsprung-Russell diagram reveal a very wide range of ages forstars belonging to these groups. These groups are most probably relatedto the dynamical perturbation by transient spiral waves (as recentlymodelled by De Simone et al. \cite{Simone2004}) rather than to clusterremnants. A possible explanation for the presence of younggroup/clusters in the same area of the UV-plane is that they have beenput there by the spiral wave associated with their formation, while thekinematics of the older stars of our sample has also been disturbed bythe same wave. The emerging picture is thus one of dynamical streamspervading the solar neighbourhood and travelling in the Galaxy withsimilar space velocities. The term dynamical stream is more appropriatethan the traditional term supercluster since it involves stars ofdifferent ages, not born at the same place nor at the same time. Theposition of those streams in the UV-plane is responsible for the vertexdeviation of 16.2o ± 5.6o for the wholesample. Our study suggests that the vertex deviation for youngerpopulations could have the same dynamical origin. The underlyingvelocity ellipsoid, extracted by the maximum-likelihood method afterremoval of the streams, is not centered on the value commonly acceptedfor the radial antisolar motion: it is centered on < U > =-2.78±1.07 km s-1. However, the full data set(including the various streams) does yield the usual value for theradial solar motion, when properly accounting for the biases inherent tothis kind of analysis (namely, < U > = -10.25±0.15 kms-1). This discrepancy clearly raises the essential questionof how to derive the solar motion in the presence of dynamicalperturbations altering the kinematics of the solar neighbourhood: doesthere exist in the solar neighbourhood a subset of stars having no netradial motion which can be used as a reference against which to measurethe solar motion?Based on observations performed at the Swiss 1m-telescope at OHP,France, and on data from the ESA Hipparcos astrometry satellite.Full Table \ref{taba1} is only available in electronic form at the CDSvia anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/430/165}
|
Binary Star Speckle Interferometry: Measurements and Orbits
Results of our second observational run of binary star interferometricmeasurements with an ICCD speckle camera attached to the 1.52 mtelescope of the Observatorio Astronómico Nacional at Calar Alto(Almería, Spain) in 2000 June-July are presented. The measuredangular separations range from 0.096" to 6.558". With the use of the newspeckle data, the orbits of the visual binaries WDS 14369+4813 and WDS21597+4908 are improved.
|
ICCD Speckle Observations of Binary Stars. XXIII. Measurements during 1982-1997 from Six Telescopes, with 14 New Orbits
We present 2017 observations of 1286 binary stars, observed by means ofspeckle interferometry using six telescopes over a 15 year period from1982 April to 1997 June. These measurements constitute the 23dinstallment in CHARA's speckle program at 2 to 4 m class telescopes andinclude the second major collection of measurements from the MountWilson 100 inch (2.5 m) Hooker Telescope. Orbital elements are alsopresented for 14 systems, seven of which have had no previouslypublished orbital analyses.
|
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
|
Absolute quadrant determinations from speckle observations of binary stars
Vector-autocorrelation techniques are highly suited to extractingastrometric information from very large volumes of speckle data in nearreal time, but they inherently introduce a 180-deg ambiguity in theposition-angle measurement. This can be a problem in determining theorbital motions in binaries, so an algorithm is presented whichmaintains most of the simplicity of vector autocorrelation whileremoving the quadrant ambiguity. Results are provided fromabsolute-quadrant determinations for 66 binary star systems firstresolved by the long-term GSU/CHARA speckle program. The algorithm isused to eliminate the period ambiguity in the orbit of the close visualbinary ADS 9744.
|
ICCD speckle observations of binary stars. IV - Measurements during 1986-1988 from the Kitt Peak 4 M telescope
One thousand five hundred and fifty measurements of 1006 binary starsystems observed mostly during 1986 through mid-1988 by means of speckleinterferometry with the KPNO 4-m telescope are presented. Twenty-onesystems are directly resolved for the first time, including newcomponents to the cool supergiant Alpha Her A and the Pleiades shellstar Pleione. A continuing survey of The Bright Star Catalogue yieldedeight new binaries from 293 bright stars observed. Corrections tospeckle measures from the GSU/CHARA ICCD speckle camera previouslypublished are presented and discussed.
|
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.
|
Micrometer Measurements of Visual Double Stars - Part Three -
Not Available
|
The Equatorial Coordinates of Components of Triple Stars from the Astrometric Satellite HIPPARCOS Input Catalogue - Part Two - the Results of Statistical Study of Data from Aitken's Catalogue of Double Stars / ADS
Not Available
|
Measurements of double stars at Nice with 74-cm and 50-cm refractors
A total of 717 measures of 287 binaries made at the 74-cm and 50-cmrefractors are presented. These are mostly very close binariesdiscovered recently, for which a rapid orbital motion is evident forabout 30 percent.
|
Micrometric measurements of binary stars (second list)
The results of 286 micrometric measurements of 88 binaries are given.The measurements have been made at Brera-Merate observatory during theperiod March 1983-January 1984 with a 23 cm refractor.
|
Micrometric Measures of Double Stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1974ApJS...28..413V&db_key=AST
|
Mesures d'étoiles doubles faites à Nice
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1972A&AS....6..185C&db_key=AST
|
The masses of stars above the main sequence.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1969AJ.....74..689S&db_key=AST
|
Mesures d'étoiles doubles faites au rĝfraceur de 38 cm de l'Observatoire de Nice
Not Available
|
INHABITED SKY
