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Speckle observations with PISCO in Merate: IV. Astrometric measurements of visual binaries in 2005
We present relative astrometric measurements of visual binaries madeduring the second semester of 2005, with the speckle camera PISCO at the102 cm Zeiss telescope of Brera Astronomical Observatory, in Merate. Oursample contains orbital couples as well as binaries whose motion isstill uncertain. The purpose of this long term program is to improve theaccuracy of the orbits and determine the masses of the components.\ Weperformed 130 new observations of 120 objects, with most of the angularseparations in the range 0\farcs1-4\arcsec, and with an average accuracyof 0\farcs01. Most of the position angles could be determined withoutthe usual 180° ambiguity with the application of triple-correlationtechniques, and their mean error is 0\fdg8. We have found a possible newtriple system: ADS 11077. škip0.15cm The measurements of theclosest binaries were made with a new data reduction procedure, based onmodel fitting of the background of the auto-correlations. As thisprocedure proved to be very efficient, we have re-processed the oldobservations of close binaries made with PISCO in Merate since 2004. Wethus improved 20 measurements already published and obtained 7 newmeasurements for observations that were previously reported as``unresolved".\ We finally present revised orbits for ADS 684, MCA 55Aac(in the Beta 1 Cyg-Albireo multiple system) and ADS 14783 for which thepreviously published orbits led to large residuals with our measurementsand for which the new observations made since their computation alloweda significant improvement of those old orbits. The sum of the massesthat we derived for those systems are consistent with the spectral typeof the stars and the dynamic parallaxes are in good agreement with theparallaxes measured by Hipparcos.
| 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.
| 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.
| Speckle Interferometry at the US Naval Observatory. I.
We present speckle interferometer measurements of 467 binary stars takenat the US Naval Observatory in Washington, DC, using the 66 cmrefractor, from 1990 October through 1992 December. The observingprogram is designed to provide high-quality observations of binaries inthe 0."3--3."5 range of separations and as faint as 10.0 mag. More than8000 measurements have been made to date, of which we report the resultsfor 2329. Not only is it our intent to provide accurate data forinteresting binary stars, but also, by careful calibration, to firmlyrelate the "classical" astrometry of binary stars to that being obtainedtoday by speckle and that which will soon be obtained by other moderntechniques such as long-baseline optical interferometry.
| 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.
| Locations of the components of triple star systems north of +70 deg
Micrometric measurements of triple systems north of +70 deg declinationwere made with the 10.5-inch Fraunhofer refractor of Munich UniversityObservatory. Absolute positions of all measured components were derivedby using the positions of the main stars as given in the catalog AGK3and, in some cases, also in the SAO-catalog.
| 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.
| Mikrometermessungen von Doppelsternen. VI.
Not Available
| Micrometer measures of doubles stars. III.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1963AJ.....68...57V&db_key=AST
| Yerkes actinometry. Zone +73deg to +90deg.
Not Available
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Membro dei seguenti gruppi:
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Osservazione e dati astrometrici
| Costellazione: | Cefeo |
| Ascensione retta: | 23h27m43.05s |
| Declinazione: | +74°07'09.9" |
| Magnitudine apparente: | 7.608 |
| Distanza: | 115.207 parsec |
| Moto proprio RA: | 58.7 |
| Moto proprio Dec: | 19.7 |
| B-T magnitude: | 7.926 |
| V-T magnitude: | 7.635 |
Cataloghi e designazioni:
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