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Synthetic photometry of speckle interferometric binaries The synthetic magnitudes and color indices of 46 speckle interferometricstars have been computed depending on their observational spectralenergy distributions. The Strömgren vby and Tycho BV passbands havebeen used to calculate magnitudes of the systems. These data whencombined with the magnitude differences of the sub-components fromspeckle interferometry observations will allow the finding of theparameters of the individual components. These parameters will improveour knowledge about binary system formation and evolution.
| Model atmosphere parameters of the binary systems COU1289 and COU1291 The spectral energy distributions between λ 3700 Å, andλ 8100 Å, of the binary systems COU1289 and COU1291 havebeen measured with the Carl-Zeiss-Jena 1 m telescope of the SpecialAstrophysical Observatory. Their B,V,R magnitudes and B-V colour indiceswere computed and compared with earlier investigations. Modelatmospheres of both systems were constructed using a grid of Kuruczblanketed models, their spectral energy distributions in the continuousspectrum were computed and compared with the observational ones. Themodel atmosphere parameters for the components of COU1289 were derivedas: T_eff{a} =7100 K, T_eff{b}=6300 K, logg_a=4.22, log g_b=4.22, R_a=1.50 Rȯ, R_b=1.40Rȯ, and for the components of COU1291 as:T_eff{a}=6400 K, T_eff{b} =6100 K, log g_a=4.20,log g_b=4.35, R_a=1.47 Rȯ, R_b=1.12 Rȯ.The spectral types of both components of the system COU1289 wereconcluded as F1 and F7, and of the system COU1291 as F6 and F9. Finallythe formation and evolution of the systems were discussed.
| Orbits and masses of twenty double stars discovered by Paul Couteau In this article we present the orbits and masses of 20 double starsdiscovered by P. Couteau at the Nice Observatory (France), namely WDS01450+2703 (COU 750), 03321+4340 (1688), 03423+3141 (691), 06503+2409(768), 12409+2708 (596),14138+3059 (606), 15390+2545 (612), 16584+3943(1289), 17075+3810 (1291), 17221+2310 (415), 18035+ 4032 (1785),18043+4206 (1786), 19089+3404 (1462), 19180+2012 (321), 20151+3742(2416), 20216+1930 (327 AB), 21593+4606 (2138), 22077+2622 (537),22307+1758 (234) and 23199+2844 (439). For two of these stars, COU 750and COU 1289, these are the first orbits to be published other than IAUCirculars; for the others, previously published orbits are improved onby those presented here. Star masses were in fifteen cases calculatedfrom Hipparcos parallax data, and in the other five from dynamicalparallaxes; in all cases, the error is estimated. Some of the otherphysical and orbital properties of these stars are also discussed.All the figures and tables are only available in electronic form athttp://www.edpsciences.org
| Spectral energy distributions and model atmosphere parameters of the binary systems COU1289 and COU1291 The spectral energy distribution between λ3700 Å andλ8100 Å of the binary systems COU1289 and COU1291 ispresented with a description of the methodology of getting theirspectrum on Carl-Zeiss-Jena 1 m telescope of the Special AstrophysicalObservatory. Their B, V, R magnitudes and B-V colour indices werecomputed and compared with earlier results. Model atmospheres of bothsystems were constructed using the grid of the Kurucz blanketed models,and their energy distributions in the continuous spectrum were computedand compared with the observational ones. The model atmosphereparameters for the components of COU1289 were derived as:Teffa = 7100K, Teffb =6300K, lg ga = 4.27, lg gb = 4.22, Ra =1.50Rsolar, Rb = 1.40Rsolar, and forthe components of COU1291 as: Teffa = 6400K,Teffb = 6100K, lg ga = 4.20, lggb = 4.35, Ra = 1.47Rsolar,Rb = 1.12Rsolar. The spectral types of bothcomponents of the system COU1289 were approved as F1 and F7, and of thesystem COU1291 as F6 and F9. Finally the formation and evolution of thesystems were discussed.
| Speckle interferometry of nearby multiple stars We present the results of diffraction-limited optical speckleinterferometry and infrared bispectrum speckle interferometry of 111double and 10 triple systems performed in 1998-1999 with the 6-mtelescope of the Special Astrophysical Observatory in Zelenchuk. Theobservations concentrated on nearby close binaries discovered during theHipparcos mission. Many nearby fast-orbiting low-mass binaries knownbefore Hipparcos were also included in the program. New companions werefirst resolved in 4 systems: HIP 5245, ADS 3179, Kui 99, and ADS 16138.In addition to accurate relative positions, magnitude differences weremeasured for most of the pairs. We combined our results with theHipparcos parallaxes to derive absolute magnitudes and spectral typesfor 63 binaries and 4 triples. Preliminary orbital elements and themass-sum are derived for HIP 689, and improved orbits are presented forHIP 16602 (CHR 117) and HIP 21280 (CHR 17). Based on data collected atthe Special Astrophysical Observatory, Russia Table 1 is only, and Table2 also, available in electronic form at the CDS via anonymons ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/385/87
| 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.
| The radial-azimuthal instability of a hot two-temperature accretion disc with advection The radial-azimuthal instability of a hot two-temperature accretion discwith advection is examined in this paper. We find that the inclusion ofvery little advection has significant effects on two acoustic modes fora geometrically thin, cooling-dominated two-temperature disc, but has noeffect on acoustic modes for a geometrically slim, cooling-dominatedtwo-temperature disc. We also find that, when azimuthal perturbationsare considered, the stability properties of the disc are different fromthose in the pure radial perturbation case. An increase of the azimuthalwavenumber will stabilize the acoustic modes but make the viscous andthermal modes more unstable for a geometrically thin, cooling-dominatedtwo-temperature disc. It makes the thermal mode more unstable and theacoustic mode more stable, but only affects the instability of theviscous mode for short-wavelength perturbations for a geometricallyslim, cooling-dominated two-temperature disc. For a geometrically slim,advection-dominated two-temperature disc, the increase of the azimuthalperturbation makes the I- and O-modes more stable and the thermal modemore unstable, but has no effect on the viscous mode.
| 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.
| New orbits. Not Available
| Mesures d'etoiles doubles faites aux lunettes de 74 et 50 CM de l'Observatoire de la Cote d'Azur We give 657 measurements of double stars, Table 1 by R. Gili with CCDcamera, Table 2 by P. Couteau with filar micrometer. Tables 1 and 2 areonly available in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html.
| 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. 11: Measurements during 1991-1993 from the Kitt Peak 4 M telescope One-thousand one-hundred ninety-seven observations of 730 binary starsystems, observed by means of speckle interferometry with the 4 mtelescope on Kitt Peak, are presented. Included in these binary starsare new interferometric companions to five visual binaries. Thesemeasurements, made mostly during the period 1991 to 1993, comprise the11th installment of results stemming from our speckle program at the 4 mclass telescopes on Kitt Peak, Cerro Tololo, and Mauna Kea.
| Mesures d'etoiles doubles faites a Nice, etoiles doubles nouvelles (24eme serie) decouvertes a Nice. Table 1 gives 1182 measurements of 682 binaries observed with the 74 and50 cm refractors. Table 2 lists 26 new binaries discovered with the 50cm refractor.
| Measurements of close binaries performed at PIC DU Midi A total of 241 measurements of 119 close binaries observed with the 2-mTelescope Bernard Lyot at Pic du Midi Observatory are given. Themeasurements were performed with a micrometer with illuminated wires.
| Interferometric observations of double stars in 1986-1990 A tabulation is presented for the measurements of double stars that havebeen conducted with the photometric phase-grating interferometer of theMt. Sanglok 1-m reflector. The tabulation encompasses the observationepoch, the position angle, the separation in arcsec, the magnitudedifference, formal errors in P.A. and separation, SAO number, andcoordinates for 2000.0.
| Binary-star measurements carried out at PIC DU Midi and at Nice Data on 219 measurements of 103 close binaries observed with the 2mtelescope at Pic du Midi are presented. Also presented are data on 230measurements of 126 binaries observed with the 74 cm refractor of theNice Observatory.
| Speckle Measurements of Binary Stars / 6-METER Telescope - 1987-1988 Not Available
| A first catalogue of speckle-interferometric measurements of binary stars made with 6-m telescope of the USSR AS. Not Available
| Measurements of binary stars obtained at Pic-du-Midi and at Nice A total of 112 visual measurements of 82 close binaries observed with 2mtelescope at Pic-du-Midi are presented. In addition, 344 measurements of163 close binaries were observed with the 74-cm and 50-cm refractors atNice. All measurements were made by a micrometer with illuminated wires.
| 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.
| Speckle Interferometry Measurements of Binaries Using the 6-METER Telescope in 1986 Not Available
| Binary star measurements made at Pic-du-Midi The 2-m Pic-du-Midi telescope has been used to obtain 130 visualmeasurements of 64 very close binaries. The measurements were made withan illuminated cross wire micrometer which provided magnificationfactors of 2500 to 5000. Data are presented in tabular form for suchmeasurements as total visual magnitude, angular position andseparations, and period.
| Interferometric Observations of Double Stars in 1985 and 1986 Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1988A&AS...72..563T&db_key=AST
| Measurements of visual double stars made at PIC DU Midi and at Nice Fifty visual measures of 37 very close binaries observed with the 2-mtelescope at Pic du Midi are presented together with 601 measures of 245close binaries observed with the 74-cm and 50-cm refractors at Nice. Allmeasurements were made by micrometer with illuminated wires. With the2-m telescope, binaries as close as 0.07 arcsec are separated, usingmagnifying powers from 2500 to 5000.
| 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.
| Photographic Astrometry of Binary and Proper-Motion Stars - Part Two Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1986AJ.....92..446H&db_key=AST
| 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.
| Digital speckle interferometry of binary stars Observations of 46 suspected spectroscopic or visual binary starsobtained using a television speckle interferometer with digital dataaccumulation on the 6-m telescope of the Special AstrophysicalObservatory at Nizhni Arkhyz during April and June, 1983, are reported.The television system employs a 256 x 256 raster and 50-Hz frame rateand the two-dimensional autocorrelation-function (ACF) algorithm ofBlazit et al. (1975); filters used have central wavelengths andbandwidths 600 and 16 nm (orange), 656 and 12 nm (red), 525 and 10 nm(green), and 435 and 12 nm (blue). A typical three-dimensional ACF mapof binaries are given in a table; and the 21 unresolved objects arelisted separately. The separations of the resolved pairs range from 29to 270 marcsecs.
| Micrometer Measures of Double Stars at Lick Observatory Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1984PASP...96..174C&db_key=AST
| Measurements of binary stars made at Nice Results are presented for 753 measurements of 267 binary stars that weremade with the 50- and 74-cm refractors at Nice Observatory. Coordinatesfor the equinox of 1950 are provided, along with apparent magnitudes,spectral types, and probable periods. It is noted that three-quarters ofthese systems are recently discovered close binaries.
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Osservazione e dati astrometrici
Costellazione: | Ercole |
Ascensione retta: | 17h07m29.99s |
Declinazione: | +38°10'20.6" |
Magnitudine apparente: | 8.584 |
Distanza: | 113.636 parsec |
Moto proprio RA: | -14.2 |
Moto proprio Dec: | 9 |
B-T magnitude: | 9.191 |
V-T magnitude: | 8.635 |
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