J/AJ/143/5 uvby photometry and RVs of HD 74057 (Sowell+, 2012)
Absolute properties of the highly eccentric, solar-type eclipsing binary
HD 74057.
Sowell J.R., Henry G.W., Fekel F.C.
<Astron. J., 143, 5 (2012)>
=2012AJ....143....5S 2012AJ....143....5S
ADC_Keywords: Photometry, uvby ; Binaries, eclipsing ; Stars, F-type ;
Stars, late-type ; Radial velocities
Keywords: binaries: close - binaries: eclipsing - binaries: spectroscopic
Abstract:
We have obtained Stromgren b and y differential photometric
observations of the solar-type eclipsing binary HD 74057 plus
follow-up high-resolution, red wavelength spectroscopic observations.
The system has an orbital period of 31.2198 days, a high eccentricity
of 0.47, and is seen almost exactly edge on with an inclination of
89.8°. The two main-sequence G0 stars are nearly identical in all
physical characteristics. We used the Wilson-Devinney program to
obtain a simultaneous solution of our photometric and spectroscopic
observations. The resulting masses of the components are
M1=1.138±0.003M☉ and M2=1.131±0.003M☉, and the radii
are R1=1.064±0.002R☉ and R2=1.049±0.002R☉. The
effective temperatures are 5900K (fixed) and 5843K, and the iron
abundance, [Fe/H], is estimated to be +0.07. A comparison with
evolutionary tracks suggests that the system may be even more metal
rich. The components rotate with periods of 8.4 days, significantly
faster than the predicted pseudosynchronous period of 12.7days. We
see evidence that one or both components have cool spots. Both stars
are close to the zero-age main sequence and are about 1.0Gyr old.
Description:
Our photometric observations of HD 74057 were acquired during its
2001-2002 and 2004-2005 observing seasons with the T10 0.80m
Automatic Photometric Telescope (APT) located at Fairborn Observatory
in the Patagonia Mountains of southern Arizona. T10 has a two-channel
precision photometer that uses a dichroic beam splitter to enable the
simultaneous measurement of the Stromgren b and y passbands.
We acquired 99 and 68 nightly brightness measurements of HD 74057
during the 2001-2002 and 2004-2005 observing seasons, respectively.
The 2001-2002 and 2004-2005 nightly (D-A) out-of-eclipse observations
are presented as the first 167 rows of Table 1.
On six nights during the 2004-2005 observing season, we used the
T10 APT to acquire higher-cadence observations for several hours each
night during primary and secondary eclipse. A total of 1067
differential magnitudes was acquired on these six nights. They are
listed in Table 1, immediately after the out-of-eclipse observations
From 2002 February to 2007 June, 27 observations, obtained at
double-lined phases, were acquired with the Coude feed telescope,
Coude spectrograph, and a TI CCD detector at the Kitt Peak National
Observatory (KPNO).
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
08 42 46.21 +31 51 45.4 HD 7405 = HIP 42753
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 31 1234 Photometric observations
table2.dat 37 26 Radial velocities
--------------------------------------------------------------------------------
See also:
II/215 : uvby-beta Catalogue (Hauck+ 1997)
II/291 : Third Photometric Magnitude Difference Catalog (Mason, 2008)
J/A+A/387/850 : Radial velocities of eclipsing binaries (Imbert, 2002)
J/A+A/446/785 : Catalogue of eclipsing variables (Malkov+, 2006)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [52196.9/53510.7] Heliocentric Julian Date;
(HJD-2400000.0)
12- 17 F6.4 --- Phase Phase (1)
19- 24 F6.3 mag Dymag [0.974/1.725] Differential y band magnitude
26- 31 F6.3 mag Dbmag [1.082/1.845] Differential b band magnitude
--------------------------------------------------------------------------------
Note (1): Based on parameter values listed in Table 6.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 d HJD [52327.8/54223.7] Heliocentric Julian Date;
(HJD-2400000)
11- 15 F5.3 --- Phase Phase (1)
17- 21 F5.1 km/s RV1 [-34.5/64.5] Primary radial velocities
23- 26 F4.1 km/s O-C1 [-0.5/0.4] Primary O-C residuals (1)
28- 32 F5.1 km/s RV2 [-55.6/44.7] Secondary radial velocities
34- 37 F4.1 km/s O-C2 [-0.3/0.4] Secondary O-C residuals (1)
--------------------------------------------------------------------------------
Note (1): Phases and (O-C) residuals are computed with the spectroscopic
values presented in Table 3.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 02-Apr-2013