J/AJ/165/247 Radial velocity follow up of KIC 7284688 system (Pan+, 2023)
KIC 7284688: a solar-type eclipsing binary with rapidly varying O'Connell
effect.
Pan Y., Zhang X.
<Astron. J., 165, 247 (2023)>
=2023AJ....165..247P 2023AJ....165..247P
ADC_Keywords: Binaries, eclipsing; Stars, double and multiple; Spectra, optical;
Radial velocities
Keywords: Eclipsing binary stars ; Stellar rotation ; Starspots
Abstract:
We present comprehensive photometric and spectroscopic study of the
short-period eclipsing binary KIC7284688 based on the Kepler, TESS,
and LAMOST data. The radial-velocity analysis indicates that it is a
triple-lined system composed of a nearly equal-mass binary plus a
line-of-sight star. The masses and radii of the components in the
binary are measured to be M1=1.142±0.020M☉,
R1=1.204±0.051R☉, and M2=1.119±0.019M☉,
R2=1.149±0.052R☉. In addition to the eclipses, the light
curves of the binary exhibit exhibit rapidly changing O'Connell
effect, namely the inequality in light maxima, which could be
attributed to the asynchronous rotation of the starspots. We analyzed
the variability in the data of light residuals, the difference between
light maxima (Max.I-Max.II) as well as the epochs of light minima and
determined a rotation period of 0.644 days. Moreover, we detected a
quasiperiod with ∼213days from both the data of (Max.I-Max.II) and
light times of minima, which is almost identical to the beat between
the rotation period (∼0.644days) and the orbital period (∼0.646days).
We conclude that the quasiperiodic variations of the O'Connell on the
system are probably related to the starspot migration and this is a
very rapid variation compared to the magnetic cycles with timescales
ranging from years to decades.
Description:
KIC7284688 was observed by LAMOST-Kepler (LK) survey in low-resolution
and medium-resolution mode. The spectral resolution and wavelength
range are R∼1800 and 370-900nm for the low-resolution mode, and, in
the medium-resolution mode, the spectral resolution is R∼7500, and the
wavelength range is 495-535nm and 630-680nm. In total, four
low-resolution spectra and 71 medium-resolution ones with
signal-to-noise ratios in the range 24-85 were obtained
Objects:
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RA (2000) DE Designation(s)
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19 30 31.20 +42 49 45.5 KIC 7284688 = 2MASS J19303120+4249456
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 55 71 KIC 7284688 radial-velocity measurements
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See also:
J/AJ/106/2096 : Limb-darkening coefficients in binaries (Van Hamme 1993)
J/AJ/141/83 : Kepler Mission. I. Eclipsing binaries in DR1 (Prsa+, 2011)
J/AJ/142/160 : Kepler Mission. II. Eclipsing binaries DR2 (Slawson+, 2011)
J/AJ/147/45 : Kepler mission. IV. Eclipse times close bins (Conroy+, 2014)
J/MNRAS/448/429 : Starspots in short-period Kepler binaries (Balaji+, 2015)
J/ApJS/220/19 : LAMOST obs. in the Kepler field. I. (De Cat+, 2015)
J/ApJS/224/37 : White-light flares on close binaries from Kepler (Gao+, 2016)
J/AJ/151/68 : Kepler Mission. VII. Eclipsing binaries in DR3 (Kirk+, 2016)
J/A+A/600/A30 : Limb-darkening for TESS satellite (Claret, 2017)
J/AJ/154/250 : Kepler EB classifications and rotation periods (Lurie+, 2017)
J/AJ/153/231 : BVR photometry of EPIC 211957146 (Sriram+, 2017)
J/ApJS/238/30 : LAMOST obs. in Kepler field. II. LRS sp. 5yrs (Zong+, 2018)
J/ApJ/877/75 : BVRI photom. of DV Psc and known short-period EBs (Pi+, 2019)
J/ApJS/251/15 : LAMOST-Kepler/K2 survey first year obs. (Zong+, 2020)
J/AJ/161/46 : (O-C) curve of the binary system KIC 06852488 (Shi+, 2021)
J/ApJS/256/14 : RVs from LAMOST MRS DR7 stellar spectra (Zhang+, 2021)
J/A+A/664/A78 : Kepler targets class based on LAMOST spectra (Frasca+, 2022)
J/ApJS/262/10 : Kepler eclipsing binaries with Gaia data (Knote+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.5 d BJD [8263/9017] Barycentric Julian Date; BJD-2450000
12- 17 F6.4 --- Porb [0.008/0.99] Orbital phase
19- 25 F7.2 km/s RVel1 [-143/151]? 1st companion radial velocity
27- 31 F5.2 km/s e_RVel1 [1/16]? Error on RVel1
33- 39 F7.2 km/s RVel2 [-164/152]? 2nd companion radial velocity
41- 45 F5.2 km/s e_RVel2 [1/17]? Error on RVel2
47- 50 F4.2 km/s RVel3 [0.18/8.11] 3rd companion radial velocity
52- 55 F4.2 km/s e_RVel3 [0.1/1]? Error on RVel3
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History:
From electronic version of the journal
(End) Prepared by Coralie Fix [CDS], 12-Jan-2024