Light curves for DV Piscium. The upper panel, plotted from TESS data,[1] shows the periodic variability due to eclipses. The bottom panel, adapted from Zhang et al.,[2] shows the flare which occurred at UT 11:00 on Nov. 22, 2008, in three photometric bands.
Combining photometric results across several years demonstrated that the light curve is highly variable, with star spot activity on both components. This varied over time in quantity, size, and location.[12] This is a detached binary system with the components in near contact at a separation of just two solar radii. As of 2007, the period of the system is decreasing over time at a rate of about −8.6×10−7 d·yr–1.[7] The primary component has 68% of the mass of the Sun and 73% of the Sun's radius; the cooler secondary has 47% of the mass and 52% of the radius of the Sun.[9] Both components are slightly evolvedmain sequence stars. The system has an activity cycle estimated at 14.74±0.84 years.[5]
Evidence from O–C diagrams suggests there is a third component to this system, orbiting the inner pair with a period of 9.79±0.60 years on an eccentric orbit. This body has less than 62% of the mass of the Sun.[9]
^ abZhang, Liyun; Zhang, Xiliang; Zhu, Zhongzhong (April 2010), "The CCD photometric study of the newly identified RS CVn binary star DV Piscium", New Astronomy, 15 (4): 362–366, Bibcode:2010NewA...15..362Z, doi:10.1016/j.newast.2009.10.004.
^Robb, R. M.; Wagg, J.; Berndsen, A.; Desroches, L. (November 1999), "Photometry of the Eclipsing Binary Star GSC 0008 324 = 1RXS J001309+053550", Information Bulletin on Variable Stars, 4800: 1, Bibcode:1999IBVS.4800....1R.
^Parimucha, Š.; Pribulla, T.; Rucinski, S.; Kaluzny, J.; Thompson, I.; Vaňko, M.; Hambálek, L. (December 2010), Prša, Andrej; Zejda, Miloslav (eds.), "Preliminary Analysis of DV Psc: A Spotted, Short-Period Eclipsing Binary", Binaries - Key to Comprehension of the Universe. Proceedings of a conference held June 8-12, 2009 in Brno, Czech Republic, vol. 435, San Francisco: Astronomical Society of the Pacific, p. 99, Bibcode:2010ASPC..435...99P.
Further reading
Pi, Qing-feng; Zhang, Li-yun; Bi, Shao-lan; Han, Xianming L.; Lu, Hong-peng; Yue, Qiang; Long, Liu; Yan, Yan (June 2019), "Magnetic Activity and Orbital Period Study for the Short-period RS CVn-type Eclipsing Binary DV Psc", The Astrophysical Journal, 877 (2): 75, Bibcode:2019ApJ...877...75P, doi:10.3847/1538-4357/ab19c3, S2CID191144926, 75.
Pi, Qing-feng; Zhang, Li-Yun; Li, Zhong-mu; Zhang, Xi-liang (March 2014), "Magnetic Activity and Orbital Period Variation of the Short-period Eclipsing Binary DV Psc", The Astronomical Journal, 147 (3): 50, Bibcode:2014AJ....147...50P, doi:10.1088/0004-6256/147/3/50, S2CID250769694, 50.
Pi, Qingfeng; Zhang, Liyun; Li, Zhongmu; Sang, Hongyan; Zhu, Zhongzhong (September 2012), "Photometric study of the short-period RS CVn eclipsing binary DV Psc", arXiv:1209.1862 [astro-ph.SR]