J/AJ/147/50 Differential BVRI light curves of DV Psc (Pi+, 2014)
Magnetic activity and orbital period variation of the short-period eclipsing
binary DV Psc.
Pi Q.-F., Zhang L.-Y., Li Z.-M., Zhang X.-L.
<Astron. J., 147, 50 (2014)>
=2014AJ....147...50P 2014AJ....147...50P
ADC_Keywords: Binaries, eclipsing ; Photometry, UBVRI ; Photometry, CCD
Keywords: binaries: eclipsing - stars: chromospheres - stars: flare -
stars: late-type - starspots
Abstract:
We present six new BVRcIc CCD light curves of a short-period RS
CVn binary DV Psc obtained in 2010-2012. The light curve distortions
change on both short and long timescales, which is explained by two
starspots on the primary component. Moreover, five new flare events
were detected and the flare ratio of DV Psc is about 0.082 flares per
hour. There is a possible relation between the phases (longitude) of
the flares and starspots for all of the available data of late-type
binaries, which implies a correlation of the stellar activity of the
spots and flares. The cyclic oscillation, with a period of
4.9±0.4yr, may result from the magnetic activity cycle, identified
by the variability of Max.I-Max.II. Until now, there were no
spectroscopic studies of chromospheric activity indicators of the
Hβand Hγlines for DV Psc. Our observations of these
indicators show that DV Psc is active, with excess emissions. The
updated O-C diagram with an observing time span of about 15yr shows an
upward parabola, which indicates a secular increase in the orbital
period of DV Psc. The orbital period secularly increases at a rate of
dP/dt=2.0x10-7days/yr, which might be explained by the angular
momentum exchanges or mass transfer from the secondary to primary
component.
Description:
The CCD photometric observations of DV Psc were performed using the
85cm telescope at Xinglong station of the National Astronomical
Observatories of China (NAOC). The photometer was equipped with a
1024*1024 pixel CCD and the standard Johnson-Cousins-Bessell set
of BVRcIc filters were used.
Objects:
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RA (ICRS) DE Designation(s) (Period)
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00 13 09.20 +05 35 43.1 DV Psc = GSC 00008-00324 (P=0.308536)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 98 2143 BVRc and Ic photometric data of DV Psc
taken in 2008, 2010, 2011, and 2012
table4.dat 101 14 Newly obtained times of minimum light of DV Psc
table5.dat 47 99 The minimum times of DV Psc
refs.dat 81 16 References
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See also:
B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)
B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Year Year of the observation
6- 7 I2 month Month Month of the observation
9- 18 A10 d Day Day(s) of the observation
20- 31 F12.4 d HJD-B ? Heliocentric Julian Date of B band observation
33- 38 F6.3 mag DBmag ? Differential Johnson B band magnitude (1)
40- 51 F12.4 d HJD-V ? Heliocentric Julian Date of V band observation
53- 58 F6.3 mag DVmag ? Differential Johnson V band magnitude (1)
60- 71 F12.4 d HJD-R ? Heliocentric Julian Date of R band observation
73- 78 F6.3 mag DRmag ? Differential Cousins R band magnitude (1)
80- 91 F12.4 d HJD-I ? Heliocentric Julian Date of I band observation
93- 98 F6.3 mag DImag ? Differential Cousins I band magnitude (1)
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Note (1): Magnitude difference in the sense of DV Psc minus the comparison star.
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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- 11 F11.5 d HJD-B Heliocentric Julian Date of B band observation
13- 19 F7.5 d e_HJD-B Uncertainty in HJD-B
21- 31 F11.5 d HJD-V ? Heliocentric Julian Date of V band observation
33- 39 F7.5 d e_HJD-V ? Uncertainty in HJD-V
41- 51 F11.5 d HJD-R Heliocentric Julian Date of R band observation
53- 59 F7.5 d e_HJD-R Uncertainty in HJD-R
61- 71 F11.5 d HJD-I Heliocentric Julian Date of I band observation
73- 79 F7.5 d e_HJD-I Uncertainty in HJD-I
81- 90 F10.4 d Mean Heliocentric Julian Date in the BVRI bands
92- 97 F6.4 d e_ Uncertainty in
99-101 A3 --- Type Minimum type (Pri=primary, Sec=secondary)
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 d HJD Heliocentric Julian Date (HJD-2400000) (1)
12- 17 F6.4 d e_HJD Uncertainty in HJD
18 A1 --- f_HJD [*] The data from O-C gateway by mark (*) (2)
20- 22 A3 --- Meth [ccd] Method of observation
24- 30 F7.1 --- Cycle [-8483/7202] Cycle number
32- 37 F6.4 d O-C1 The (O-C)1 residual
39- 44 F6.4 d O-C2 The (O-C)2 residual
46- 47 I2 --- Ref Reference; in refs.dat file
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Note (1): All published minimum times were collected from the literature and the
Eclipsing Binaries Minima Database (available at http://var2.astro.cz/EN/;
Paschke & Brat, 2006OEJV...23...13P 2006OEJV...23...13P)
Note (2): http://var.astro.cz/ocgate/.
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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 Reference number
4- 22 A19 --- BibCode Bibliographic code
24- 39 A16 --- Aut Author's name
41- 81 A41 --- Com Comments
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History:
From electronic version of the journal
References:
Pi et al. Paper II. 2017AJ....154..260P 2017AJ....154..260P, Cat. J/AJ/154/260
Lu et al. Paper III. 2018AJ....156...88L 2018AJ....156...88L
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 08-Sep-2014