J/ApJ/894/96 V-band phot. & spectra of the EB BT Vul (Torres+, 2020)
Absolute dimensions of the unevolved F-type eclipsing binary BT Vulpeculae.
Torres G., Lacy C.H.S., Fekel F.C., Muterspaugh M.W.
<Astrophys. J., 894, 96 (2020)>
=2020ApJ...894...96T 2020ApJ...894...96T
ADC_Keywords: Binaries, eclipsing; Photometry; Spectra, optical;
Radial velocities; Stars, F-type
Keywords: Eclipsing binary stars ; Stellar evolution ;
Fundamental parameters of stars ;
CCD photometry ; Radial velocity ; Spectroscopy
Abstract:
We report extensive differential V-band photometry and high-resolution
spectroscopy for the 1.14d, detached, double-lined eclipsing binary
BT Vul (F0+F7). Our radial-velocity monitoring and light-curve
analysis lead to absolute masses and radii of
M1=1.5439±0.0098M☉N and R1=1.536±0.018R☉N for the
primary, and M2=1.2196±0.0080M☉N and
R2=1.151±0.029R☉N for the secondary. The effective
temperatures are 7270±150K and 6260±180K, respectively. Both stars
are rapid rotators, and the orbit is circular. A comparison with
stellar evolution models from the MESA Isochrones and Stellar Tracks
series shows excellent agreement with these determinations, for a
composition of [Fe/H]=+0.08 and an age of 350Myr. The two components
of BT Vul are very near the zero-age main sequence.
Description:
Times of minimum light have been gathered for BT Vul since 1953 using
photographic, visual, and photoelectric/CCD techniques. The available
measurements are collected in Table 1, which contains 115 timings for
the primary minimum and 40 for the secondary over more than 65yr.
See Section 2.1.
Spectroscopic monitoring of BT Vul was carried out at two facilities
(see Section 2.2.).
Observations at the Center for Astrophysics (CfA) with the Tillinghast
Reflector Echelle Spectrograph (TRES) mounted on the 1.5m Tillinghast
reflector at the Fred L. Whipple Observatory on Mount Hopkins
(Arizona, USA) began in June of 2010 and continued until October of
2015. A total of 39 spectra were gathered at a resolving power of
R∼44000, and cover the wavelength region 3800-9100Å in 51 orders.
Further spectroscopic observations of BT Vul were obtained from 2011
November through 2018 September at Fairborn Observatory, which is
situated in southeast Arizona near Washington Camp. The observations
were acquired with the Tennessee State University 2m Automatic
Spectroscopic Telescope (AST) and a fiber-fed echelle spectrograph
(R∼15000 at 6000Å).
Two web-based telescopes were used to gather differential photometric
observations of BT Vul: the URSA WebScope (see
Torres+ 2009, J/AJ/138/1622) and
the NFO WebScope (see Grauer+ 2008PASP..120..992G 2008PASP..120..992G). See Section 2.3.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
20 23 04.93 +27 28 39.0 BT Vul = TYC 2164-161-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 54 155 Times of Minimum Light for BT Vul
table2.dat 44 39 CfA Radial Velocities for BT Vul
table3.dat 32 52 Fairborn Radial Velocities for BT Vul
table5.dat 17 5451 URSA WebScope Observations of BT Vul
table6.dat 17 6018 NFO WebScope Observations of BT Vul
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
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 single-lined sp. binaries (Latham, 2002)
J/A+A/450/681 : Companions to close sp. binaries (Tokovinin+, 2006)
J/AJ/138/1622 : Absolute properties of LV Her (Torres+, 2009)
J/other/IBVS/5889 : Minima and maxima of 380 variables (Hubscher+, 2009)
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/ApJ/742/123 : Photometry and Velocity of LSPM J1112+7626 (Irwin+, 2011)
J/AJ/145/111 : RVs of five spectroscopic binaries (Fekel+, 2013)
J/ApJS/208/9 : Colors & temperatures of PMS stars (Pecaut+, 2013)
J/AN/334/860 : Cat. of eclipsing variables. V2 (Avvakumova+, 2013)
J/AJ/147/36 : Photometry and spectroscopy of AQ Ser (Torres+, 2014)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 F11.5 d HJD [34740.28/58690.655] Heliocentric Julian Date,
HJD-2400000 (1)
13- 21 F9.4 yr Year [1953.99/2019.57] Fractional year, minimum light
23- 30 F8.1 --- Epoch [-16421/4566] Epoch from reference time of
primary minimum, cycles
32- 39 F8.6 d Unc [0.00027/0.04] Uncertainty, days (2)
41- 49 F9.6 d O-C [-0.025/0.026] Residual
51- 51 I1 --- Ecl [1/2] Eclipse type (3)
53- 54 A2 --- Type Observation type (4)
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Note (1): Sources for the individual measurements are listed at
http://var2.astro.cz/EN/brno/eclipsing_binaries.php and
http://www.bav-astro.eu/index.php/veroeffentlichungen/
service-for-scientists/lkdb-engl
Note (2): For measurements with published uncertainties the errors reported
here have been multiplied by scale factors of 3.35 and 2.75 for the
photoelectric timings of the primary and secondary minima (see text),
and scale factors of 4.35 and 1.28 for the visual observations.
Measurements with no published errors have been assigned values of
0.0063 days, 0.010 days, and 0.0058 days for the photographic, visual,
and photoelectric techniques, respectively.
Note (3): Eclipse type corresponds to (1) for the primary and (2) for
the secondary minimum.
Note (4): Observation type as follows:
PG = photographic (2 occurrences);
V = visual (31 occurrences);
PE = photoelectric/CCD techniques (122 occurrences).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [55368.9/57297.7] Heliocentric Julian Date,
HJD-2400000
12- 18 F7.2 km/s RV1 [-152/107] Radial velocity, Primary
20- 26 F7.2 km/s RV2 [-186/141] Radial velocity, Secondary
28- 31 F4.2 km/s e_RV1 [1.8/5.1] Uncertainty in RV1
33- 36 F4.2 km/s e_RV2 [1.8/5.1] Uncertainty in RV2
38- 44 F7.5 --- Phase [0.18/0.84] Orbital Phase (1)
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Note (1): Orbital phase calculated from the reference time of primary eclipse.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [55867.7/58376.65] Heliocentric Julian Date,
HJD-2400000
12- 17 F6.1 km/s RV1 [-152/108] Radial velocity, Primary (1)
19- 24 F6.1 km/s RV2 [-183/142] Radial velocity, Secondary (1)
26- 32 F7.5 --- Phase [0.08/0.92] Orbital Phase (2)
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Note (1): Typical uncertainties for the velocities are 3.0km/s for the
primary and 3.4km/s for the secondary.
Note (2): Orbital phase calculated from the reference time of primary eclipse.
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Byte-by-byte Description of file: table[56].dat
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Bytes Format Units Label Explanations
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1- 11 F11.5 d HJD [52831.6/56600.7] Heliocentric Julian Date,
HJD-2400000
13- 17 F5.3 mag dVmag [1.47/2.34] Magnitude difference,
variable - comps (1)
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Note (1): The measurement dVmag is defined as "variable-comps", where "comps"
is the sum of the brightness of all three comparison stars.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-Sep-2021