Physical Parameters of Late-type Contact Binaries in the Northern Catalina Sky Survey

Abstract

We present the physical parameters of 2335 late-type contact binary (CB) systems extracted from the Catalina Sky Survey (CSS). Our sample was selected from the CSS Data Release 1 by strictly limiting the prevailing temperature uncertainties and light-curve fitting residuals, allowing us to almost eliminate any possible contaminants. We developed an automatic Wilson-Devinney-type code to derive the relative properties of CBs based on their light-curve morphology. By adopting the distances derived from CB (orbital) period-luminosity relations (PLRs), combined with the well-defined massluminosity relation for the systems' primary stars and assuming solar metallicity, we calculated the objects' masses, radii, and luminosities. Our sample of fully eclipsing CBs contains 1530 W-, 710 A-, and 95 B-type CBs. A comparison with literature data and with the results from different surveys confirms the accuracy and coherence of our measurements. The period distributions of the various CB subtypes are different, hinting at a possible evolutionary sequence. W-type CBs are clearly located in a strip in the total mass versus mass ratio plane, while A-type CBs may exhibit a slightly different dependence. There are no significant differences among the PLRs of A-and W-type CBs, but the PLR zero points are affected by their mass ratios and fill-out factors. Determination of zero-point differences for different types of CBs may help us improve the accuracy of the resulting PLRs. We demonstrate that automated approaches to deriving CB properties could be a powerful tool for application to the much larger CB samples expected to result from future surveys.

Photometric and Spectroscopic analysis of four contact binaries

“…They found a mass-ratio of 0.19 for J0305 which is smaller than the estimated value of 0.31 in the present study. However, it should be noted that Sun et al (2020) used only V band data in their analysis and a primary component cooler by 150 K than the present value hence some disagreement between the two estimates could be possible. The total mass (M t ) determined for all the systems is above minimum total mass limit for EWs except for KW Psc.…”

“…Therefore, in the present analysis, we followed the procedure adopted by Liu et al (2020) for calculating the physical parameters. Recently Sun et al (2020) derived parameters of 2335 late-type contact binaries from the CSS survey including the system J0305. They found a mass-ratio of 0.19 for J0305 which is smaller than the estimated value of 0.31 in the present study.…”

Eclipsing Binary Populations across the Northern Galactic Plane from the KISOGP survey

“…Among ∼8 million stars whose time-series data were examined, more than 50,000 objects were selected as candidate variable stars (N. Matsunaga et al, in prep.). In this paper, 7752 candidate variables are considered for our EBS selection, based on Fourier analysis, with periods determined in Section 2.2 (Chen et al 2020).…”

“…We selected our EBS sample using the same method as that proposed by Chen et al (2020). Contamination of our sample by non-binary objects is less than 1%, based on careful visual examination.…”

Zwicky Transient Facility and Globular Clusters: the Period–Luminosity and Period–Luminosity–Color Relations for Late-type Contact Binaries

“…Using a much larger sample of CB, Jayasinghe et al (2020) showed that early-type and late-type CB follow a different PL relation. Finally, Sun et al (2020) divided CB into three sub-classes and derived the mid-infrared W 1-band PL relation for each of them.…”