P. P. Campo

Precise orbital elements, masses and parallax of the spectroscopic–interferometric binary HD 26441

The orbit of the visual-speckle binary A 2801 (HD 26441) was calculated independently of the previously published double-lined spectroscopic solution, obtaining similar values for the common orbital elements. In this way, it has been possible to provide a consistent 3D orbit and precise values for both the orbital parallax and the individual masses of the components, so the physical properties of this stellar system are determined.

Physical and geometrical parameters of CVBS. XII. FIN 350 (HIP 64838)

A complete astrophysical and dynamical study of the close visual binary system (CVBS) Finsen 350 (A7V + F0V), is presented. Beginning with the entire observational spectral energy distribution (SED) and the magnitude difference between the subcomponents, Al-Wardat’s complex method for analyzing CVBS was applied as a reverse method of building the individual and entire synthetic SEDs of the system. This was combined with Docobo’s analytic method to calculate the new orbits. Although possible short (approximately 9 years) and long period (of about 18 years) orbits could be considered taking into account the similar results of the stellar masses obtained for each of them (3.07 and 3.41 M⊙, respectively), we confirmed that the short solution is correct. In addition, other physical, geometrical and dynamical parameters of this system such as the effective temperatures, surface gravity accelerations, absolute magnitudes, radii, the dynamical parallax, etc., are reported. The Main Sequence phase of both components with age around 0.79 Gyr is approved.

New distances for a selected set of visual binaries with inconsistent dynamical masses

We have selected a set of 17 visual binaries that demonstrate great inconsistency between the systemic mass obtained through Kepler’s Third Law as compared to that calculated through standard mass-luminosity and mass-spectrum relationships. A careful inspection of orbital data and parallaxes showed that the current orbits of nine binaries (WDS 00155–1608, WDS 00174+0853, WDS 05017+2050, WDS 06410+0954, WDS 16212–2536, WDS 17336–3706, WDS 19217–1557, WDS 20312+1116, and WDS 21118+5959) do not need to be improved, instead we recommend different parallax (distance) value for them. On the other hand, we considered that eight orbits (WDS 02366+1227, WDS 02434–6643, WDS 03244–1539, WDS 08507+1800, WDS 09128–6055, WDS 11532–1540, WDS 17375+2419, and WDS 22408–0333) had to be improved. Due to various reasons mentioned in this paper, their distances should most likely be corrected unless better orbital solutions and/or more precise parallaxes are reported. To obtain consistent mass values, the use of the dynamical parallax is still recommended for 5 out of the 8 improved orbits. For WDS 02434–6643, WDS 09128–6055, and WDS 11532–1540, the improvement itself yields reasonable mass sums while maintaining πHip

An analytic algorithm to calculate the inclination, ascending node, and semimajor axis of spectroscopic binary orbits using a single speckle measurement and the parallax

\pi_{\mathrm{Hip}}

Analysis of the September ε-Perseid outburst in 2013

within a 1–2σ

ORBITS OF 12 SOUTHERN BINARIES BASED ON SOAR SPECKLE OBSERVATIONS

1\mbox{--}2\sigma

Guests in double stars

margin. New distance estimates for 16 stars (mainly based on the obtained dynamical parallaxes) and individual comments for all objects are presented and discussed.

A methodology for studying physical and dynamical properties of multiple stars. Application to the system of red dwarfs Gl 22

It is well known that in spectroscopic binary orbits, the inclination, the ascending node, and the semimajor axis remain undetermined, therefore the principal objective of this research is to establish an analytic methodology for the calculation of these parameters for spectroscopic binaries, both single-lined (SB1) and double-lined (SB2). In other words, the goal is to determine their “three-dimensional” orbits using a single speckle measurement (ρ, θ, t) and the parallax (π). Moreover, estimates of the individual masses of each system can also be obtained. The proposed algorithm was successfully applied to SB1 systems: YSC 148 (HD 37393) and CHR 225 (HD 34318), and SB2 systems: LSC 1 Aa1,2 (HD 200077) and Mkt 11 Aa, Ab (HD 358). In this late case, previously determined spectroscopic and visual orbits have been used to compare and contrast the results obtained from them with our results. The methodology presented is especially interesting for those cases in which it is only possible to resolve the spectroscopic binary in the zones of maximum angular separation by optical means thereby making it impossible to avail of sufficient observations in order to calculate the visual orbit.

Improved orbits and parallaxes for eight visual binaries with unrealistic previous masses using the Hipparcos parallax

We acknowledge support from the Spanish Ministry of Science and Innovation (projects AYA2015-68646-P and AYA 2015-67175-P).

The three-dimensional orbit and physical properties of the binary COU 2031 (WDS 04464+4221, HIP 22196, HD 30090)

New data obtained with the 4.1 m Southern Astrophysical Research (SOAR) telescope at Cerro Pachon, Chile, allowed us to revise the orbits and system masses of the following southern visual double stars: WDS 01477-4358 (I 52), WDS 01500-0408 (A 2602), WDS 02514-2139 (DON 43), WDS 03189-0101 (BU 1177), WDS 04142-4608 (RST 2338), WDS 06274-2544 (B 114), WDS 18434-5546 (B 398), WDS 20002-5522 (B 459 BC), WDS 20081-3929 (RST 2134), WDS 22007-5002 (I 1450), and WDS 22504-1744 (DON 1038—BD-18 6201). In addition, the orbit of the WDS 15332-2429 Aa, Ab (CHR 232 Aa, Ab) system was calculated for the first time. When available, we used the Hipparcos parallax to check the accuracy of our calculations of individual masses. In some cases, the dynamical parallaxes directly obtained from the orbital elements may be more valid than the satellite data. As far as the lack of spectral data and parallax associated with the WDS 22504-1744 (DON 1038 or BD-18 6201) system is concerned, we were able to assign a spectral type using the orbital elements along with the dynamical parallax and photometric information available. Other orbital and physical properties of these stars are also discussed herein.