J/AJ/167/280 Photometry and spectroscopy of V505 Lac (Jeong+, 2024)
Simultaneous Photometric and Spectroscopic Analysis of V505 Lacertae, a
Photospherically and Chromospherically Active Contact Binary Star.
Jeong M.-J., Kim C.-H., Hong K., Kim H.-Y., Song M.-H., Park J.-H.,
Han C.
<Astron. J., 167, 280 (2024)>
=2024AJ....167..280J 2024AJ....167..280J
ADC_Keywords: Binaries, eclipsing; Photometry, UBVRI; Spectra, optical;
Keywords: Eclipsing binary stars ; Contact binary stars ; CCD photometry
; Spectroscopy ; Radial velocity ; Eclipsing binary minima
timing method ; Stellar activity ; Starspots ; Stellar evolution
Abstract:
New BVR photometric and high-resolution spectroscopic observations of
V505 Lac are presented with Transiting Exoplanet Survey Satellite
(TESS) photometric data. The orbital period has experienced a secular
decrease during the past 16yr. A clear anticorrelation in the primary
and secondary eclipse timing variation (PSETV) obtained from the TESS
data is also identified. A double-lined radial velocity (RV) curve is
secured, and the effective temperatures of the less- and more-massive
stars (Stars 1 and 2, respectively) are measured. Using a spectral
subtraction technique, excess emissions are detected in the
time-series CaII H and K and Hα lines for Star 2. Simultaneous
analysis of the light and RV curves using the Wilson-Devinney (WD)
code reveals that V505-Lac is a photospherically and chromospherically
active W-subtype contact binary system. The component-star masses and
radii are determined to an accuracy of approximately 1%. The WD spot
model is individually applied to 221 light curves segmented from the
TESS data so as to derive the spot parameters of a cool spot on Star
2. The combined variations in both longitude and colatitude among the
spot parameters appear to be strongly associated with those of both
the anticorrelation in the PSETV and the O'Connell effect in the TESS
light curves. Robust negative linear relationships between the PSETV
anticorrelation size and the O'Connell effect magnitude are found for
the first time. Mass-radius, mass-luminosity, and mass ratio-mass
diagrams of contact binaries, along with the mass ratio frequency
distribution, are presented in an attempt to elucidate the
evolutionary characteristics of these systems.
Description:
Ground-based photometric observations of V505 Lac were performed for
three nights on 2019 September 29 and 30 and October 27 at the
Sobaeksan Optical Astronomy Observatory (SOAO), Korea. The SOAO has a
61cm Boller and Chivens reflector equipped with a standard Johnson BVR
filter set and an FLI 4K CCD camera with a field of view (FoV) of
15.2x15.2'.
TESS observations of V505 Lac with a 120s cadence were performed in
Sectors 16 (2019 September 12-October 6), 56 (2022 September 1-30),
and 57 (2022 September 30-October 29).
Objects:
----------------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------------
22 42 47.72 +45 21 05.2 V505 Lac = 1SWASP J224247.72+452105.2
----------------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 50 380 BVR measurements of V505 Lac obtained at the SOAO
tablea1.dat 60 511 All V505 Lac times of minimum light
tableb1.dat 51 221 Variation of spot parameters over time
--------------------------------------------------------------------------------
See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
VI/120 : High-resolution synthetic stellar library (Coelho+, 2005)
J/AJ/106/2096 : Limb-darkening coefficients in binaries (Van Hamme 1993)
J/ApJ/469/355 : Teff, B-V and BC relation (Flower, 1996)
J/A+A/311/523 : Photometry of W UMa (Maceroni+, 1996)
J/A+AS/146/103 : CaII H&K to CaII IRT echelle spectra (Montes+, 2000)
J/AcA/54/207 : Ephemerids of eclipsing binaries (Kreiner, 2004)
J/AJ/142/99 : BVRI observations of TZ Boo (Christopoulou+, 2011)
J/MNRAS/430/2029 : Initial masses W UMa type contact binaries (Yildiz+, 2013)
J/MNRAS/448/429 : Starspots in short-period Kepler binaries (Balaji+, 2015)
J/other/IBVS/6155 : 81th name-list of variable stars. II. (Kazarovets+, 2015)
J/AJ/153/231 : BVR photometry of EPIC 211957146 (Sriram+, 2017)
J/AJ/158/193 : Photometric data of V582 Lyr and V1016 Oph (Cheng+, 2019)
J/ApJS/247/50 : Late-type contact binaries in CSS DR1 (Sun+, 2020)
J/AJ/162/147 : Prot of 43 TOIs with Evryscope and TESS (Howard+, 2021)
J/AJ/162/13 : Parameters estimation 173 eclipsing binaries (Li+, 2021)
J/AJ/161/221 : Photometry & spectroscopy 4 binaries stars (Panchal+, 2021)
J/ApJ/927/12 : Long-term photometric analysis of 5 EBs (Panchal+, 2022)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 d HJDB [755/785]? Heliocentric Julian Date; JD-2458000
for B-band measurements
11- 16 F6.3 mag DeltamB [-0.73/-0.39]? B-band magnitude difference
between V505 Lac and comparison star
18- 26 F9.5 d HJDV [755/785]? Heliocentric Julian Date; JD-2458000
for V-band measurements
28- 33 F6.3 mag DeltamV [-0.3/0.006]? V-band magnitude difference between
V505 Lac and comparison star
35- 43 F9.5 d HJDR [755/785] Heliocentric Julian Date; JD-2458000
for R-band measurements
45- 50 F6.3 mag DeltamR [-0.09/0.23] R-band magnitude difference between
V505 Lac and comparison star
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 F14.6 d HJD [2453965/2459894] Time of minimum light in
Heliocentric Julian Date
16- 23 F8.6 d e_HJD [2e-05/0.005]? Uncertainty in HJD
25- 26 A2 --- Type Primary timing = I, Secondary timing = II
28- 34 F7.1 --- Epoch [0/18128] Epoch number
36- 60 A25 --- r_Epoch Reference for Epoch (1)
--------------------------------------------------------------------------------
Note (1): References as follows:
Lewandowski et al. (2009) = 2009OEJV..104....1L 2009OEJV..104....1L
Nelson (2013) = 2013IBVS.6050....1N 2013IBVS.6050....1N
Hubscher (2016) = 2016IBVS.6157....1H 2016IBVS.6157....1H
Samolyk (2016) = 2016JAVSO..44..164S 2016JAVSO..44..164S
Hubscher (2017) = 2017IBVS.6196....1H 2017IBVS.6196....1H
Nagai (2018) = 2018VSOLJ.....64
Nelson (2018) = 2018IBVS.6234....1N 2018IBVS.6234....1N
Pagel (2018) = 2018IBVS.6244....1P 2018IBVS.6244....1P
Lehky et al. (2021) = 2021OEJV..211....1L 2021OEJV..211....1L
Pagel (2020) = 2020BAVJ...33....1P 2020BAVJ...33....1P
Nagai (2020) = 2020VSOLJ.....67
Paschke (2020) = 2020BAVJ...40....1P 2020BAVJ...40....1P
Nelson (2022) = 2022OEJV..226....1N 2022OEJV..226....1N
Samolyk (2023) = 2023JAVSO..51..134S 2023JAVSO..51..134S
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Epoch [14597/18092] Epoch calculated from first point
of each dataset
7- 11 F5.2 deg theta [11.12/60.45] Co-latitude of starspot
13- 16 F4.2 deg e_theta [0.17/5.08] Uncertainty in theta
18- 23 F6.2 deg phi [136.36/245.75] Longitude of starspot
25- 28 F4.2 deg e_phi [0.58/1.66] Uncertainty in phi
30- 34 F5.2 deg rspot [13.98/25.49] Angular radius of starspot
36- 39 F4.2 deg e_rspot [0.05/1.95] Uncertainty in rspot
41- 45 F5.3 --- Ts/T* [0.871/0.873] Temperature ratio of local spot to
local unspotted star, Tspot/Tstar
47- 51 F5.3 --- e_Ts/T* [0.001/0.003] Uncertainty in Ts/T*
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 17-Jun-2024