J/ApJ/887/109 EBs in Ruprecht 147. II. EPIC 219568666 LC & RVs (Torres+, 2019)
Eclipsing binaries in the open cluster Ruprecht 147.
II. EPIC 219568666.
Torres G., Vanderburg A., Curtis J.L., Ciardi D., Kraus A.L., Rizzuto A.C.,
Ireland M.J., Lund M.B., Christiansen J.L., Beichman C.A.
<Astrophys. J., 887, 109-109 (2019)>
=2019ApJ...887..109T 2019ApJ...887..109T (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing; Clusters, open; Photometry; Optical;
Radial velocities
Keywords: Eclipsing binary stars; Open star clusters
Stellar evolutionary models; Light curves
Fundamental parameters of stars; Stellar ages
Abstract:
We report our spectroscopic monitoring of the detached, grazing, and
slightly eccentric 12 day double-lined eclipsing binary EPIC 219568666
in the old nearby open cluster Ruprecht 147. This is the second
eclipsing system to be analyzed in this cluster, following our earlier
study of EPIC 219394517. Our analysis of the radial velocities
combined with the light curve from the K2 mission yields absolute
masses and radii for EPIC 219568666 of M1=1.121±0.013M☉ and
R1=1.1779±0.0070R☉ for the F8 primary and
M2=0.7334±0.0050M☉ and R2=0.640±0.017R☉ for the
faint secondary. Comparison with current stellar evolution models
calculated for the known metallicity of the cluster points to a
primary star that is oversized, as is often seen in active M dwarfs,
but this seems rather unlikely for a star of its mass and with a low
level of activity. Instead, we suspect a subtle bias in the radius
ratio inferred from the photometry, despite our best efforts to avoid
it, which may be related to the presence of spots on one or both
stars. The radius sum for the binary, which bypasses this possible
problem, indicates an age of 2.76±0.61Gyr, which is in good
agreement with a similar estimate from the binary in our earlier
study.
Description:
EPIC 219568666 was observed by K2 during its seventh observing
campaign for 81 days between 2015 October and December, with a cadence
of 29.4 minutes (3654 measurements).
Spectroscopic monitoring of EPIC 219568666 was carried out between
2016 May and 2018 June with the Tillinghast Reflector Echelle
Spectrograph (TRES) on the 1.5m Tillinghast reflector at the
Fred L. Whipple Observatory on Mount Hopkins (Arizona, USA). We
gathered a total of 25 spectra at a resolving power of R∼44000
covering the wavelength region 3800-9100Å in 51 orders.
Objects:
--------------------------------------------------------------
RA (ICRS) DE Designation(s)
--------------------------------------------------------------
19 16 59.93 -16 25 17.6 EPIC 219568666 = TYC 6296-2012-1
--------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 21 3654 Detrended K2 photometry of EPIC 219568666
table3.dat 40 25 Heliocentric radial-velocity measurements of
EPIC 219568666
--------------------------------------------------------------------------------
See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/322 : UCAC4 Catalogue (Zacharias+, 2012)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/469/355 : Teff, B-V and BC relation (Flower, 1996)
J/AJ/124/1144 : Orbits of 171 single-lined sp. binaries (Latham, 2002)
J/ApJ/640/1018 : Differential photometry of V1061 Cyg (Torres+, 2006)
J/AJ/136/2158 : CV Boo V-band and radial velocity curves (Torres+, 2008)
J/A+A/502/253 : V636 Cen radial velocities curves (Clausen+, 2009)
J/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010)
J/A+A/512/A54 : Teff and Fbol from Infrared Flux Method (Casagrande+, 2010)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/ApJ/742/123 : Photometry and Velocity of LSPM J1112+7626 (Irwin+, 2011)
J/AJ/145/134 : Radial velocities of 108 stars in Ruprecht 147 (Curtis+, 2013)
J/MNRAS/454/2863 : Teff against colours calibrations (Huang+, 2015)
J/ApJS/222/14 : Planetary cand. from 1st yr K2 mission (Vanderburg+, 2016)
J/AJ/152/8 : Stellar multiplicity on planetary systems I. (Kraus+, 2016)
J/AJ/153/71 : Kepler follow-up observation prog. I. Imaging (Furlan+, 2017)
J/AJ/155/114 : HAT-TR-318-007: a double-lined M dwarf binary (Hartman+, 2018)
J/A+A/618/A93 : Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)
J/A+A/619/A176 : Chemical composition of Ruprecht 147 (Bragaglia+, 2018)
J/A+A/625/A115 : Ruprecht 147 DANCe. I. (Olivares+, 2019)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [57301.48/57382.81] Heliocentric Julian Date;
HJD-2400000
12- 21 F10.8 --- Flux [0.89/1.01] Detrended (Residual) flux
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [57528.9/58294.83] Heliocentric Julian Date;
HJD-2400000
12- 16 F5.2 km/s HRV1 [-7.2/82] Heliocentric Radial Velocity,
component 1
18- 21 F4.2 km/s e_HRV1 [0.1/0.25] Uncertainty in HRV1 (1)
23- 28 F6.2 km/s HRV2 [-22.3/117.3] Heliocentric Radial Velocity,
component 2
30- 33 F4.2 km/s e_HRV2 [0.9/2.4] Uncertainty in HRV2 (1)
35- 40 F6.4 --- Phase [0.043/0.97] Orbital Phase (2)
--------------------------------------------------------------------------------
Note (1): Final velocity uncertainties result from scaling the values listed
for the primary and secondary by the near-unity factors f_1 and f_2,
respectively, from our global analysis described in Section 3.
Note (2): Orbital phases are counted from the reference time of primary eclipse.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Torres et al. Paper I. 2018ApJ...866...67T 2018ApJ...866...67T
Torres et al. Paper II. 2019ApJ...887..109T 2019ApJ...887..109T This catalog
Torres et al. Paper III. 2020ApJ...896..162T 2020ApJ...896..162T Cat. J/ApJ/896/162
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-May-2021