scholarly journals On the component masses of visual binaries

2010 ◽  
pp. 71-80 ◽  
Author(s):  
Zorica Cvetkovic ◽  
S. Ninkovic
Keyword(s):  
Binary Stars ◽  
Total Mass ◽  
Input Data ◽  
Main Sequence ◽  
Clear Indication ◽  
Orbital Elements ◽  
High Quality ◽  
Large Dispersion ◽  
Visual Binary Stars ◽  
Visual Binaries

In the Sixth Catalog of Orbits of Visual Binary Stars we found those belonging to the Main Sequence to form a sample containing 432 visual binaries. Their total masses were obtained dynamically, i.e. they were calculated using the orbital elements and the new Hipparcos parallaxes. For the same pairs the total mass was also found astrophysically - by applying the mass-luminosity relation. The apparent magnitudes of the components were found in two different ways: by deriving them from total magnitudes and magnitude differences, and by taking their values directly from a catalogue. The results for these two approaches show no essential discrepancy. The values of total masses obtained dynamically have a large dispersion involving even completely unrealistic values. This is a clear indication that the input data are not sufficiently reliable. Nevertheless, in a large number of cases the agreement between total masses obtained by us in two different ways is quite satisfactory indicating that i) for many visual binaries, as a rule not too distant and with high-quality orbital elements, the dynamical total masses can be reliable; ii) the mass-luminosity relation yields quite satisfactory estimates for the component masses when they belong to the Main Sequence and iii) a correlation between the relative parallax error and orbit grade exists.

scholarly journals A Mass Estimate in a Sample of Double Stars

2006 ◽  
Vol 2 (S240) ◽  
pp. 631-633
Author(s):  
S. Ninković ◽  
Z. Cvetković
Keyword(s):  
Binary Stars ◽  
Main Sequence ◽  
Apparent Magnitude ◽  
Orbital Elements ◽  
Double Stars ◽  
Trigonometric Parallax ◽  
Hipparcos Catalogue ◽  
Mass Estimate ◽  
Visual Binary Stars ◽  
Magnitude Difference

AbstractThe total masses of binaries are calculated on the basis of their orbital elements from the Sixth Catalog of Orbits of Visual Binary Stars. They are then compared with the values resulted from the mass-luminosity relation for the Main Sequence where as the input data are used: trigonometric parallax, total apparent magnitude of the pair (source Hipparcos Catalogue) and magnitude difference (source Hipparcos Catalogue and Photometric Magnitude Difference Catalog). It seems that for the pairs indicated as having qualitative orbital elements the agreement between the total-mass values obtained in these two ways is satisfactory.

scholarly journals Visual Binaries and the Calibration of the Main Sequence

1985 ◽  
Vol 111 ◽  
pp. 397-400
Author(s):  
Karl D. Rakos
Keyword(s):  
Binary Stars ◽  
Binary Systems ◽  
Main Sequence ◽  
Open Cluster ◽  
Age Group ◽  
Hot Stars ◽  
Visual Binary ◽  
Visual Binary Stars ◽  
Independent Calibration ◽  
Visual Binaries

147 of the best known visual binary stars have been used for an independent calibration of the main sequence in the interval −0m.15 ≤B-V≤0m.80. The (Mv, B-V) diagram is found to be equal to the composite open cluster diagram for the age group between 8.35 and 8.43 × 108 years - very hot stars excepted. The cosmic scatter of the main sequence is discussed. It appears that only a small number of visual binaries in our sample are simple binary systems.

scholarly journals Masses of the components of SB2 binaries observed with Gaia – V. Accurate SB2 orbits for 10 binaries and masses of the components of 5 binaries

2020 ◽  
Vol 496 (2) ◽  
pp. 1355-1368
Author(s):  
J-L Halbwachs ◽  
F Kiefer ◽  
Y Lebreton ◽  
H M J Boffin ◽  
F Arenou ◽  
...  
Keyword(s):  
Radial Velocity ◽  
Binary Stars ◽  
Main Sequence ◽  
Spectroscopic Binaries ◽  
Orbital Elements ◽  
Evolved Stars ◽  
The Individual ◽  
The Masses ◽  
Stellar Masses ◽  
Selection Of

ABSTRACT Double-lined spectroscopic binaries (SB2s) are one of the main sources of stellar masses, as additional observations are only needed to give the inclinations of the orbital planes in order to obtain the individual masses of the components. For this reason, we are observing a selection of SB2s using the SOPHIE spectrograph at the Haute-Provence observatory in order to precisely determine their orbital elements. Our objective is to finally obtain masses with an accuracy of the order of one per cent by combining our radial velocity (RV) measurements and the astrometric measurements that will come from the Gaia satellite. We present here the RVs and the re-determined orbits of 10 SB2s. In order to verify the masses, we will derive from Gaia, we obtained interferometric measurements of the ESO VLTI for one of these SB2s. Adding the interferometric or speckle measurements already published by us or by others for four other stars, we finally obtain the masses of the components of five binary stars, with masses ranging from 0.51 to 2.2 solar masses, including main-sequence dwarfs and some more evolved stars whose location in the HR diagram has been estimated.

scholarly journals Determination of Age and Original Chemical Composition of Binary Stars

1993 ◽  
Vol 137 ◽  
pp. 472-473
Author(s):  
S. Ferluga ◽  
M. Antillon
Keyword(s):  
Chemical Composition ◽  
Binary System ◽  
Numerical Method ◽  
Binary Stars ◽  
Input Data ◽  
Main Sequence ◽  
Surface Gravity ◽  
System Input

AbstractA numerical method is presented, which is able to determine quantitatively the age t and the initial abundances of helium and metals (Y0, Z0) of a given binary system. Input data are simply the values of mass m, temperature Teff and surface gravity g, of both stars. The procedure works for detached main-sequence binaries, and it does not require any preliminary hypothesis about surface abundances or age. It is assumed that the two stars evolve parallely with no interaction.

Astrometry and Spectroscopy as Tools Toward Visual-Binary Masses

1992 ◽  
Vol 135 ◽  
pp. 273-275
Author(s):  
W.D. Heintz
Keyword(s):  
High Precision ◽  
Main Sequence ◽  
Mass Determination ◽  
Orbital Elements ◽  
High Quality ◽  
Visual Binary ◽  
Mass Ratios ◽  
The Status ◽  
Sequence Components

Following the diversified topic of this conference, let me present a variety of comments — not all new, but resulting from a long string of stars drifting across the desk. The chase after visual orbital elements is not exactly a self-purpose but is aiming at further data, in particular, at good masses. The last published lists of high-quality mass determination represent the status of 20 years ago; but a compilation at this time would probably not last long as the progress promises to quicken.We have 1000 positional (visual/photographic/speckle) orbits, among them about 700 acceptable in the range from fair to definitive. Yet less than 10% of them give good component masses. Most of them are outside the range of parallax measures with the requisite, high precision (that unfortunatly holds for the Hyades); some frustrate the parallax measurer by displaying wedge– and peanut–shaped images, and the more exciting cases of abnormal, non-main–sequence components often cannot get good mass ratios owing to large distances or long periods.

Blended Visual Binaries as Tests of Low Amplitude Orbit Detection and Determination Capability in Long-Focus Photographic Astrometry

1983 ◽  
Vol 62 ◽  
pp. 45-51
Author(s):  
Sarah Lee Lippincott ◽  
John L. Hershey
Keyword(s):  
Main Sequence ◽  
Orbital Motion ◽  
Orbital Elements ◽  
Detection Capability ◽  
Single Star ◽  
Planetary Mass ◽  
Residual Series ◽  
Nearby Stars ◽  
Low Amplitude ◽  
Visual Binaries

AbstractPhotocentric orbital motions from 60-year Sproul plate series are shown for three visual binaries, ζ Her, 85 Peg and Ho 296. Mass ratios of the first two pairs, which have large-amplitude blended orbits, carry internal errors at the level of one percent. Orbital elements computed independently from the blended photographic observations agree closely with the well-determined visual orbits. Ho 296 serves as a test of the Sproul plate series to detect a 20-year orbit with an amplitude of two, or one, micron. Simulations of orbital motion in single star residual series confirm this detection capability, which corresponds to planetary mass for dark objects around nearby stars. A mass-luminosity diagram of the lower main sequence is shown, including one for invisible astrometric companions.

scholarly journals Orbital elements of five close visual binary stars

2000 ◽  
Vol 321 (4) ◽  
pp. 255-262 ◽  
Author(s):  
M. Scardia ◽  
J.-L. Prieur ◽  
E. Aristidi ◽  
L. Koechlin
Keyword(s):  
Binary Stars ◽  
Orbital Elements ◽  
Visual Binary ◽  
Visual Binary Stars

scholarly journals Fission and the Origin of Binary Stars

1970 ◽  
Vol 4 ◽  
pp. 147-156
Author(s):  
Jeremiah P. Ostriker
Keyword(s):  
Angular Momentum ◽  
Recent Work ◽  
Binary Stars ◽  
Total Mass ◽  
Binary Systems ◽  
Main Sequence ◽  
Rotating Stars ◽  
Early Type ◽  
Theoretical Predictions ◽  
Zero Viscosity

AbstractBrief reviews of the classical ‘angular momentum problem’ and the statistics of upper-main-sequence binaries are presented as background for the suggestion that the close, early-type, binaries are produced by fission of rapidly rotating protostars.Next, theoretical sequences of contracting, rotating stars are described. Recent work demonstrates that the zero-viscosity, polytropic sequences, have essentially the same properties as the McLaurin sequence. Thus, fission is possible for centrally condensed stars. Observations of close early-type binaries are compared with theoretical predictions for the minimum angular momentum in binary systems of given total mass; the agreement is excellent.Finally, the existing theoretical objections to the fission hypothesis for the origin of binary stars are reviewed, and it is concluded that, although fission remains unproven, there are now no strong theoretical arguments against the process, and there is considerable observational support for its existence.

scholarly journals Statistical Analysis of a Comprehensive List of Visual Binaries

2015 ◽  
Vol 24 (4) ◽  
Author(s):  
D. Kovaleva ◽  
O. Malkov ◽  
L. Yungelson ◽  
D. Chulkov ◽  
G. M. Yikdem
Keyword(s):  
Statistical Analysis ◽  
Binary Stars ◽  
Statistical Investigation ◽  
Physical Parameters ◽  
Class V ◽  
Luminosity Class ◽  
Comprehensive List ◽  
Visual Binary Stars ◽  
Cross Matching ◽  
Visual Binaries

AbstractVisual binary stars are the most abundant class of observed binaries. The most comprehensive list of data on visual binaries compiled recently by cross-matching the largest catalogues of visual binaries allowed a statistical investigation of observational parameters of these systems. The dataset was cleaned by correcting uncertainties and misclassifications, and supplemented with available parallax data. The refined dataset is free from technical biases and contains 3676 presumably physical visual pairs of luminosity class V with known angular separations, magnitudes of the components, spectral types, and parallaxes. We also compiled a restricted sample of 998 pairs free from observational biases due to the probability of binary discovery. Certain distributions of observational and physical parameters of stars of our dataset are discussed.

scholarly journals Preliminary orbital elements of six visual binary stars

2008 ◽  
Vol 329 (4) ◽  
pp. 379-386 ◽  
Author(s):  
M. Scardia ◽  
J.-L. Prieur ◽  
L. Pansecchi ◽  
R.W. Argyle
Keyword(s):  
Binary Stars ◽  
Orbital Elements ◽  
Visual Binary ◽  
Visual Binary Stars
Sign in / Sign up

Export Citation Format

Share Document