The first photometric investigation and spectroscopic analysis of two contact binaries: ASAS J124343+1531.7 and LINEAR 2323566

Abstract

The multi-color passband CCD light curves of ASAS J124343+1531.7 and LINEAR 2323566 were first obtained by the 0.84-m Ritchey-Chrétien telescope with follow up observations by the WIYN 0.90m Cassegrain telescope. The data from the $TransitingExoplanetSurveySatellite(TESS)$ of ASAS J124343+1531.7 was also applied for subsequent analysis. By analyzing the data through the W-D program, their mass ratios and fill-out factors were determined as 3.758, 1.438 and 31.8$\%$, 14.9$\%$, respectively. ASAS J124343+1531.7 is a W-subtype median contact binary, while LINEAR 2323566 is a W-subtype shallow contact binary, and the asymmetric light curves prove that they both have the O'Connell effect, which is generally explained by magnetic activity. The equivalent widths (EWs) of H${}_{\alpha }$ lines were calculated, which show they certainly have magnetic activity. Moreover, LINEAR 2323566 has a stronger magnetic activity. The analysis of orbital period changes shows that ASAS J124343+1531.7 has a trend of secular period increase, which is generally explained by the mass transfer from the less massive to the more massive star. According to the estimated absolute parameters, their evolutionary states are discussed. The two components of ASAS J124343+1531.7 are both main sequence stars. While for LINEAR 2323566, the more massive star is a main sequence star, the less massive star has evolved out of main sequence and is over-luminous and over-sized.

26 pages, 10 figures, abd 8 tables, accepted by PASP

References in corpus (7)

• The Gaia mission
• The Transiting Exoplanet Survey Satellite
• The Catalina Surveys Periodic Variable Star Catalog
• Physical Properties and Catalogue of EW-type Eclipsing Binaries Observed by LAMOST
• The short period end of the contact binary period distribution based on the All Sky Automated Survey (ASAS)
• Contact binaries at the short period cut-off I. statistics and the first photometric investigations of ten totally eclipsing systems
• LAMOST Spectrograph Response Curves: Stability and Application to flux calibration

Cited by in corpus (2)

• Minute-Cadence Observations of the LAMOST Fields with the TMTS: II. Catalogues of Short-Period Variable Stars from the First Two-Year Surveys
• The First Photometric and Spectroscopic Study of Contact Binary V2840 Cygni