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TX Cnc is a member of the young open cluster NGC 2632. In the present paper, four CCD epochs of light minimum and a complete V light curve of TX Cnc are presented. A period investigation based on all available photoelectric or CCD data showed that it is found to be superimposed on a long-term increase ($dP/dt=+3.97times{10^{-8}}$,days/year), and a weak evidence suggests that it includes a small-amplitude period oscillation ($A_3=0.^{d}0028$; $T_3=26.6,years$). The light curves in the V band obtained in 2004 were analyzed with the 2003 version of the W-D code. It was shown that TX Cnc is an overcontact binary system with a degree of contact factor $f=24.8%(pm0.9%)$. The absolute parameters of the system were calculated: $M_1=1.319pm0.007M_{odot}$, $M_2=0.600pm0.01M_{odot}$; $R_1=1.28pm0.19R_{odot}$, $R_2=0.91pm0.13R_{odot}$. TX Cnc may be on the TRO-controlled stage of the evolutionary scheme proposed by Qian (2001a, b; 2003a), and may contains an invisible tertiary component ($m_3approx0.097M_{odot}$). If this is true, the tertiary component has played an important role in the formation and evolution of TX Cnc by removing angular momentum from the central system(Pribulla & Rucinski, 2006). In this way the contact binary configuration can be formed in the short life time of a young open cluster via AML.
We present a comprehensive photometric analysis of a young open cluster NGC 1960 (M36) along with the long-term variability study of this cluster. Based on the kinematic data of Gaia DR2, the membership probabilities of 3871 stars are ascertained in
Deep and extensive CCD photometric observations $UBV(RI)_{C}H_{alpha}$ were carried out in the area of the open cluster NGC 3293. The new data set allows to see the entire cluster sequence down to $M_{V} approx +4.5$, revealing that stars with $M_{V}
Young open clusters are ideal laboratories to understand star formation process. We present deep UBV I and Halpha photometry for the young open cluster IC 1590 in the center of the H II region NGC 281. Early-type members are selected from UBV photome
Precision uvbyCa Hbeta photometry of the metal-deficient, old open cluster, NGC 2506, is presented. The survey covers an area 20 by 20 arcminutes, and extends to V~18 for b-y and Hbeta and to V~17.0 for c_1 and hk. For V < 16.0, photometric scatter a
In this paper we analyse the evolutionary status and properties of the old open cluster NGC 2355, located in the Galactic anticentre direction, as a part of the long term programme BOCCE. NGC 2355 was observed with LBC@LBT using the Bessel $B$, $V$,