J/AJ/146/35 BVR light curves of DZ Psc (Yang+, 2013)
Deep, low mass ratio overcontact binary systems.
XIII. DZ Piscium with intrinsic light variability.
Yang Y.-G., Qian S.-B., Zhang L.-Y., Dai H.-F., Soonthornthum B.
<Astron. J., 146, 35 (2013)>
=2013AJ....146...35Y 2013AJ....146...35Y
ADC_Keywords: Binaries, eclipsing ; Photometry, UBVRI
Keywords: binaries: eclipsing - stars: activity - stars: individual: DZ Psc
Abstract:
New multi-color photometry for the eclipsing binary DZ Psc was
performed in 2011 and 2012 using the 85cm telescope at the Xinglong
Station of the National Astronomical Observatories of China. Using the
updated Wilson-Devinney (W-D) code, we deduced two sets of photometric
solutions. The overcontact degree is f=89.7(±1.0)%, identifying DZ
Psc as a deep, low mass ratio overcontact binary. The asymmetric light
curves (i.e., LC2 in 2012) were modeled by a hot spot on the primary
star. Based on all of the available light minimum times, we discovered
that the orbital period of DZ Psc may be undergoing a secular period
increase with a cyclic variation. The modulated period and
semi-amplitude of this oscillation are Pmod=11.89(±0.19)yr and
A=0.0064(±0.0006)days, which may be possibly attributed to either
cyclic magnetic activity or light-time effect due to the third body.
The long-term period increases at a rate of
dP/dt=+7.13(±0.17)*10-7days/yr, which may be interpreted as
conserved mass transfer from the less massive component to the more
massive one. With mass transferring, DZ Psc will finally merge into a
rapid-rotation single star when Jspin/Jorb>1/3.
Description:
New multi-color photometry of DZ Psc was performed on several nights
during two observing seasons from 2011 December 22 to 2012 December
31, using the 85cm telescope at the Xinglong Station (XLs) of the
National Astronomical Observatories of China (NAOC). The standard
Johnson/Cousins set of BVIR filters was mounted.
Three primary eclipses of DZ Psc were monitored on 2009 December 6 and
2011 November 19 using the 1.0m telescope and on 2011 December 30
using the 60cm telescope at Yunnan Astronomical Observatory (YNAO) in
China.
Objects:
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RA (ICRS) DE Designation(s) (Period)
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00 36 27.94 +21 32 14.4 DZ Piscium = V* DZ Psc (P=0.3661278)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1a.dat 59 347 BVR observations of the contact binary DZ Psc in 2011
table1b.dat 59 554 BVR observations of the contact binary DZ Psc in 2012
table3.dat 29 40 Newly obtained eclipsing times for DZ Psc
table4.dat 55 53 All available light minimum times of DZ Psc
refs.dat 70 13 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)
V/119 : Catalogue of field contact binary stars (Pribulla+, 2003)
J/AJ/143/122 : VR light curves of CK Boo (Yang+, 2012; Paper XII)
J/AJ/141/44 : V396 Mon BVRI light curves (Liu+, 2011)
J/MNRAS/412/1787 : Physical parameters of 62 eclipsing binaries (Deb+, 2011)
J/AJ/131/621 : A catalog of 1022 bright contact binary stars (Gettel+, 2006)
J/AJ/130/2252 : VRI photometry of V410 Aur (Yang+, 2005; Paper IV)
J/AJ/143/122 : VR light curves of CK Boo (Yang+, 2012)
Byte-by-byte Description of file: table1[ab].dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 d HJD-B ? Heliocentric Julian Date of B band observation
14- 19 F6.3 mag DBmag ? Differential B band magnitude
21- 32 F12.4 d HJD-V Heliocentric Julian Date of V band observation
34- 39 F6.3 mag DVmag Differential V band magnitude
41- 52 F12.4 d HJD-R ? Heliocentric Julian Date of R band observation
54- 59 F6.3 mag DRmag ? Differential R band magnitude
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ne [1/19] Eclipse number
4- 16 F13.5 d HJD Heliocentric Julian Date (1)
18- 19 A2 --- Min [I /II] Type of minimum (I=primary, II=secondary)
21- 27 F7.5 d e_HJD Uncertainty on HJD
29 A1 --- Flt [BVRI] Filter (B, V, R or I)
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Note (1): Calculated from new observations and those from Gazeas et al.
(2005AcA....55..123G 2005AcA....55..123G) using the method of Kwee & van Woerden
(1956BAN....12..327K 1956BAN....12..327K).
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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
14- 21 F8.1 --- E Eclipse number (.5 for secondary minimum)
23- 25 A3 --- Meth Detection method (vi=visual, pe=photoelectric, CCD)
27- 28 A2 --- Min [I /II] Type of minimum (I=primary, II=secondary)
30- 36 F7.4 d O-C1 The (O-C)1 residual (1)
38- 44 F7.4 d O-C2 The (O-C)2 residual (2)
46- 52 F7.4 d O-C ? Final residual
54- 55 I2 --- Ref [1/13] Reference; in refs.dat file
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Note (1): Computed using the Kreiner's (2004, cat. J/AcA/54/207) linear
ephemeris: MinI=HJD2452500.0842+0.3661278*E.
Note (2): From the ephemeris: MinI=HJD2452500.0905(19)+0.36613159(31)*E.
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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- 2 I2 --- Ref [1/13] Reference number
4- 22 A19 --- BibCode Bibliographic code
24- 44 A21 --- Aut Author's name
46- 70 A25 --- Com Comments
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History:
From electronic version of the journal
References:
Qian & Yang, Paper I., 2004AJ....128.2430Q 2004AJ....128.2430Q
Zhu et al., Paper II., 2005AJ....129.2806Z 2005AJ....129.2806Z
Qian et al., Paper III., 2005AJ....130..224Q 2005AJ....130..224Q
Yang et al., Paper IV., 2005AJ....130.2252Y 2005AJ....130.2252Y, Cat. J/AJ/130/2252
Qian et al., Paper V., 2005AJ....130.1206Q 2005AJ....130.1206Q
Qian et al., Paper VI., 2006AJ....131.3028Q 2006AJ....131.3028Q
Qian et al., Paper VII., 2007AJ....134.1475Q 2007AJ....134.1475Q
Qian et al., Paper VIII., 2008AJ....136.1940Q 2008AJ....136.1940Q
Yang et al., Paper IX., 2009AJ....138..540Y 2009AJ....138..540Y
Qian et al., Paper X., 2011AJ....141..151Q 2011AJ....141..151Q
Zhu et al., Paper XI., 2011AJ....142..124Z 2011AJ....142..124Z
Yang et al., Paper XII., 2012AJ....143..122Y 2012AJ....143..122Y, Cat. J/AJ/143/122
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 24-Jun-2014