Binary Orbit, Physical Properties, and Evolutionary State of Capella (α Aurigae)

  title={Binary Orbit, Physical Properties, and Evolutionary State of Capella ($\alpha$ Aurigae)},
  author={Guillermo Torres and Antonio Claret and Patrick A. Young},
  journal={The Astrophysical Journal},
We report extensive radial velocity measurements of the two giant components of the detached, 104 day period binary system of Capella. Our highly accurate three-dimensional orbital solution based on all existing spectroscopic and astrometric observations including our own yields much improved masses for the primary and secondary of 2.466 {+-} 0.018 M {sub sun} and 2.443 {+-} 0.013 M {sub sun}, with relative errors of only 0.7% and 0.5%, respectively. The mass ratio is considerably closer to… 
Capella (alpha Aurigae) revisited: New binary orbit, physical properties, and evolutionary state
Knowledge of the chemical composition and absolute masses of Capella are key to understanding the evolutionary state of this benchmark binary system comprising two giant stars. Previous efforts,
Absolute Properties of the Highly Eccentric Eclipsing Binary Star LV Herculis
We report extensive spectroscopic and differential V-band photometric observations of the 18.4 day detached double-lined eclipsing binary LV Her (F9 V), which has the highest eccentricity (e 0.613)
The spectroscopic orbit of Capella revisited
Context. Capella is among the few binary stars with two evolved giant components. The hotter component is a chromospherically active star within the Hertzsprung gap, while the cooler star is possibly
This work presents the first quantitative composite model atmosphere analysis of Capella, the brightest near-equal-mass spectroscopic binary and principal star of the constellation Auriga. Its
The Araucaria Project: High-precision orbital parallax and masses of the eclipsing binary TZ~Fornacis
Context: Independent distance estimates are particularly useful to check the precision of other distance indicators, while accurate and precise masses are necessary to constrain evolution models.
Robotic observations of the most eccentric spectroscopic binary in the sky
Context. The visual A component of the Gliese 586AB system is a double-lined spectroscopic binary consisting of two cool stars with the exceptional orbital eccentricity of 0.976. Such an extremely
Orbital and physical parameters of eclipsing binaries from the ASAS catalogue – IX. Spotted pairs with red giants
We present spectroscopic and photometric solutions for three spotted systems with red giant components. Absolute physical and orbital parameters for these double-lined detached eclipsing binary stars
Orbital and physical parameters of eclipsing binaries from the ASAS catalogue – XI. CHIRON investigation of long-period binaries
We present the results of a spectroscopic campaign on eclipsing binaries with long orbital period (P = 20 - 75 d) carried out with the CHIRON spectrograph. Physical and orbital solutions for seven
The Araucaria Project: accurate stellar parameters and distance to evolved eclipsing binary ASAS J180057-2333.8 in Sagittarius Arm
We have analyzed the double-lined eclipsing binary system ASAS J180057-2333.8 from the All Sky Automated Survey (ASAS) catalogue . We measure absolute physical and orbital parameters for this system
The Araucaria project: High-precision orbital parallax and masses of eclipsing binaries from infrared interferometry
Context. The precise determinations of stellar mass at ≲1% provide important constraints on stellar evolution models. Accurate parallax measurements can also serve as independent benchmarks for the


Absolute Dimensions of Eclipsing Binaries. XXIII. The F-Type System EI Cephei*
We report new radial velocity measurements made with the Harvard-Smithsonian Center for Astrophysics Digital Speedometers of the F-type double-lined eclipsing binary EI Cep (P = 8.4 days), in which
A three-dimensional solution for the orbit of Capella
We have combined new radial velocities of both components of Capella, obtained at McDonald and Kitt Peak, with those recently published by Batten et al. (1991), and with interferometric observations,
Outer atmospheres of cool stars. V - IUE observations of Capella - The rotation-activity connection
We present and analyze ultraviolet spectra of Capella (G6 III +F9 III) obtained with the International Ultraviolet Explorer. High-diepersion spectra in the 115-200 A region taken at orbital velocity
On the rotation period of Capella
We present differential Hα and Hβ photometry of the very bright RS CVn-binary α Aurigae (Capella)obtained with theVienna automatic photoelectric telescope in the years 1996 through 2000. Low-level
Astrometric-Spectroscopic Determination of the Absolute Masses of the HgMn Binary Star φ Herculis
The mercury-manganese star Her is a well-known spectroscopic binary that has been the subject of a recent study by Zavala and coworkers in which they resolved the companion using long-baseline
A double-line spectroscopic orbit for Capella.
Radial-velocity spectrometer measurements of both components of the double-line Capella system have been combined with earlier radial-velocity measurements from four previous studies to produce an
A Survey of Proper-Motion Stars. XVI. Orbital Solutions for 171 Single-lined Spectroscopic Binaries*
We report 25,563 radial velocity measurements for 1359 single-lined stars in the Carney-Latham sample of 1464 stars selected for high proper motion. For 171 of these, we present spectroscopic orbital
Basic physical parameters of a selected sample of evolved stars
We present the detailed spectroscopic analysis of 72 evolved stars, which were previously studied for accurate radial velocity variations. Using one Hyades giant and another well studied star as the
Physical Orbit for λ Virginis and a Test of Stellar Evolution Models
The star λ Virginis is a well-known double-lined spectroscopic Am binary with the interesting property that both stars are very similar in abundance but one is sharp-lined and the other is
Outer atmospheres of cool stars. XIII - Capella at critical phases
The results are presented of a program of high-dispersion spectroscopy of Capella at critical orbital phases utilizing the International Ultraviolet Explorer. The considered program had the objective