J/AJ/144/149 CCD photometry of the W UMa type TY Boo (Christopoulou+, 2012)
A holistic view of the W UMa type TY Boo.
Christopoulou P.-E., Papageorgiou A., Vasileiadis T., Tsantilas S.
<Astron. J., 144, 149 (2012)>
=2012AJ....144..149C 2012AJ....144..149C
ADC_Keywords: Binaries, eclipsing ; Photometry, CCD ; Photometry, UBVRI
Keywords: binaries: close - binaries: eclipsing - stars: individual: TY Boo
Abstract:
New CCD four-color light curves of TY Boo made on eight nights over
2010-2011 were analyzed in comparison with historical light curves
obtained from 1969 through 2011. The light curves could all be
represented by a unique geometry and by wavelength consistent
photometric parameters of a two-spot model on either stellar
component. It is confirmed that TY Boo is a shallow W-type contact
binary system with a degree of contact factor of f=7.6%(±0.8). A
period investigation based on all available data shows a long-term
decrease (dP/dt=-3.65x10-8days/yr) and an oscillation (P3=58.9yr,
A=0.0254days). Without ruling out the presence of a tertiary
companion, the weight of evidence points to an active cyclic magnetic
activity that causes spot formation rather than an unseen companion.
Mass transfer between the components and angular momentum loss are
also considered as possible mechanisms.
Description:
New CCD photometric observations of TY Boo were made for eight nights
from 2010 March to July and on one night in 2011 June using the 35.5cm
f/6.3 Schmidt-Cassegrain telescope at the University of Patras
Observatory. This telescope was equipped with an SBIG ST-10 XME CCD
camera. The standard Johnson-Cousin-Bessel set of BVRcIc filters
was mounted.
Objects:
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RA (2000) DE Designation(s) (Period)
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15 00 46.94 +35 07 54.8 TY Boo = TYC 2568-953-1 (P=0.31714783)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 23 1009 BVRcIc observational data for the eclipsing
binary TY Boo
table4.dat 72 84 Added times of minimum for TY Boo (2006-2011)
refs.dat 119 28 References
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See also:
B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2013)
J/AN/334/860 : Catalogue of eclipsing variables. Ver. 2 (Avvakumova+, 2013)
J/AJ/143/99 : Photometry of W UMa eclipsing binaries (Terrell+, 2012)
J/AJ/143/30 : CCD photometry of V380 Cas (Christopoulou+, 2012)
J/AJ/142/99 : BVRI observations of TZ Boo (Christopoulou+, 2011)
J/AJ/134/179 : Ligth minimum times of TY Boo (Yang+, 2007)
J/A+A/446/785 : Catalogue of eclipsing variables (Malkov+, 2006)
J/AJ/131/621 : A catalog of 1022 bright contact binary stars (Gettel+, 2006)
J/AJ/131/2986 : Multiplicity of contact binaries (Pribulla+, 2006)
J/AcA/54/207 : Ephemerids of eclipsing binaries (Kreiner, 2004)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1 A1 --- Flt [BVRI] Filter used in the observation
among B, V, R=Rc, I=Ic
3- 16 F14.6 d HJD Heliocentric Julian Date of the observation
18- 23 F6.3 mag Dmag Differential magnitude in Flt
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 d HJD Heliocentric Julian Date of minimum light
14- 16 A3 --- Meth Detection method (ccd, pe=photoelectric)
18 A1 --- Type [PS] Type of minimum (P=primary, S=secondary)
20- 26 F7.1 --- E Epoch (cycle number)
28- 36 F9.7 d O-C The O-C value of the new minima (1)
38- 46 F9.6 d Res Residual from Eq.(4) (2)
48- 69 A22 --- Obs Observer
71- 72 I2 --- Ref Reference; in refs.dat file
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Note (1): Computed with the ephemeris of Kreiner et al. (2001aocd.book.....K 2001aocd.book.....K)
given by the equation (1) in the paper:
Min(I) = 2447612.6035+0.31714910E.
Note (2): Ephemeris as 2447612.6066+0.31714863E - 0.157x10-10E2
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Ref Reference identifier
5- 23 A19 --- BibCode Bibliographic code
25- 41 A17 --- Aut Author's name
43-119 A77 --- Com Comments
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 16-Dec-2013