Access to Astronomical Catalogues

← Click to display the menu
J/ApJ/850/10   Radial velocities of the F-type EB* V2154 Cygni   (Bright+, 2017)

Absolute dimensions of the F-type eclipsing binary V2154 Cygni. Bright J.C., Torres G. <Astrophys. J., 850, 10 (2017)> =2017ApJ...850...10B
ADC_Keywords: Binaries, eclipsing; Radial velocities Keywords: binaries: eclipsing; stars: evolution; stars: fundamental parameters; stars: individual (V2154 Cyg) ; techniques: photometric Abstract: We report spectroscopic observations of the 2.63day, detached, F-type main-sequence eclipsing binary V2154 Cyg. We use our observations together with existing uvby photometric measurements to derive accurate absolute masses and radii for the stars that are good to better than 1.5%. We obtain masses of M1=1.269±0.017M and M2=0.7542±0.0059M, radii of R1=1.477±0.012R and R2=0.7232±0.0091R, and effective temperatures of 6770±150K and 5020±150K for the primary and secondary stars, respectively. Both components appear to have their rotations synchronized with the motion in the circular orbit. A comparison of the properties of the primary with current stellar evolution models gives good agreement for a metallicity of [Fe/H]=-0.17, which is consistent with photometric estimates, and an age of about 2.2Gyr. On the other hand, the K2 secondary is larger than predicted for its mass by about 4%. Similar discrepancies are known to exist for other cool stars, and are generally ascribed to stellar activity. The system is in fact an X-ray source, and we argue that the main site of the activity is the secondary star. Indirect estimates give a strength of about 1kG for the average surface magnetic field on that star. A previously known close visual companion to V2154 Cyg is shown to be physically bound, making the system a hierarchical triple. Description: V2154 Cyg was placed on our spectroscopic program in 2001 October, and observed through 2007 June with two nearly identical echelle instruments (Digital Speedometer) on the 1.5m telescope at the Oak Ridge Observatory in the town of Harvard (MA), and on the 1.5m Tillinghast reflector at the Fred L. Whipple Observatory on Mount Hopkins (AZ). The resolving power delivered by these spectrographs was R∼35000, and the signal-to-noise ratios achieved for the 80 usable observations of V2154 Cyg range from about 20 to 67 per resolution element of 8.5km/s. Objects: -------------------------------------------------------------------- RA (ICRS) DE Designation(s) Per -------------------------------------------------------------------- 21 23 08.30 +48 31 08.1 V2154 Cyg = V* V2154 Cyg (P=2.63063) -------------------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 54 80 Heliocentric radial velocity measurements of V2154 Cyg
See also: IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999) I/276 : Tycho Double Star Catalogue (TDSC) (Fabricius+ 2002) J/ApJS/99/701 : EMSS (Fleming+ 1995) J/ApJ/469/355 : Teff, B-V and BC relation (Flower, 1996) J/A+A/363/1081 : Non-linear limb-darkening law for LTE models (Claret, 2000) J/A+A/372/588 : uvby light curves of V2154 Cyg (Rodriguez+ 2001) J/AJ/124/1144 : Orbits of 171 single-lined spectrosc. binaries (Latham, 2002) J/A+A/403/247 : Variability in the ROSAT All-Sky Survey (Fuhrmeister+, 2003) J/A+A/397/147 : Activity-rotation relationship in stars (Pizzolato+ 2003) J/A+A/450/681 : Companions to close spectroscopic binaries (Tokovinin+, 2006) J/A+A/475/677 : X-ray emission from A-type stars (Schroeder+, 2007) J/A+A/512/A54 : Teff and Fbol from Infrared Flux Method (Casagrande+, 2010) J/AJ/139/205 : 2007-2008 WIYN speckle observations of binaries (Horch+, 2010) J/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010) J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011) J/A+A/557/A119 : Eclipsing binary system LL Aquarii (Southworth, 2013) J/ApJ/780/159 : Rotation-mass-age of old field stars (Epstein+, 2014) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 10 F10.4 d HJD Heliocentric Julian Date; HJD-2400000 12- 17 F6.2 km/s RV1 [-53.8/94] Heliocentric radial velocity of star 1 19- 22 F4.2 km/s e_RV1 [0.5/2] Uncertainty in RV1 24- 30 F7.2 km/s RV2 [-107/154] Heliocentric radial velocity of star 2 32- 36 F5.2 km/s e_RV2 [4.5/15.5] Uncertainty in RV2 38- 42 F5.2 km/s RV3 [16/23.1] Heliocentric radial velocity of star 3 44- 47 F4.2 km/s e_RV3 [0.9/3.1] Uncertainty in RV3 49- 54 F6.4 --- Phase Phase (1)
Note (1): Orbital phases are computed from the reference time of primary eclipse given in Section 4.
History: From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-Jun-2018
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

catalogue service

© Université de Strasbourg/CNRS

    • Contact