First multi-band CCD photometric study for two eclipsing binaries: ASAS J212234-4627.6 and ASAS J212319-4622.4

Abstract

We present the first BVRI bands CCD photometric light curves of ASAS J212234-4627.6 and ASAS J212319-4622.4 observed with the SARA 0.6-m telescope at the Cerro Telolo Inter-American Observatory (CTIO), Chile on August 16, and September 28, 2014. From our multi-band photometry data, we obtained three minimum light times of ASAS J212234-4627.6 and four minimum light times of ASAS J212319-4622.4. We used the least square method to fit the minimum light times and got the linear ephemeris for the two eclipsing binary systems. Using the WD program, we solved the photometric solutions of the two objects: The photometric solution of ASAS J212234-4627.6 indicates that it is a semi-contact eclipsing binary star, the secondary component accurately filling its limiting lobe, and the asymmetry of the light curves may be due to the presence of a dark spot on the primary component; the photometric solution of ASAS J212319-4622.4 shows that it is a contact eclipsing binary system with a contact factor f = 5.899 ( ± 0.003)%. In addition, we also estimated the global parameters and the evolution state of the two objects. The Log Teff - Log (L/Lsun) diagram shows that the primary and secondary components of ASAS J212234-4627.6 and ASAS J212319-4622.4 are all MS stars.