The ASAS-SN catalogue of variable stars – VII. Contact binaries are different above and below the Kraft break
| Autor: | Christopher S. Kochanek, Tharindu Jayasinghe, K. Z. Stanek, Todd A. Thompson, J. L. Prieto, T W-S Holoien, N. Hurst, Marc H. Pinsonneault, Ondřej Pejcha, D. Will, Benjamin J. Shappee, G. Pojmanski, Michał Pawlak, S. Otero |
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| Rok vydání: | 2020 |
| Předmět: |
Physics
Angular momentum 010308 nuclear & particles physics FOS: Physical sciences Astronomy and Astrophysics Astrophysics Type (model theory) Effective temperature Space (mathematics) Orbital period Light curve Astrophysics - Astrophysics of Galaxies 01 natural sciences Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) 0103 physical sciences Variable star 10. No inequality 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) |
| Zdroj: | Monthly Notices of the Royal Astronomical Society |
| ISSN: | 1365-2966 0035-8711 |
| DOI: | 10.1093/mnras/staa518 |
| Popis: | We characterize ${\sim} 71,200$ W UMa type (EW) contact binaries, including ${\sim} 12,600$ new discoveries, using ASAS-SN $V$-band all-sky light curves along with archival data from Gaia, 2MASS, AllWISE, LAMOST, GALAH, RAVE, and APOGEE. There is a clean break in the EW period-luminosity relation at $\rm \log (\rm P/d){\simeq}-0.30$, separating the longer period early-type EW binaries from the shorter period, late-type systems. The two populations are even more cleanly separated in the space of period and effective temperature, by $\rm T_{eff}=6710\,K-1760\,K\,\log(P/0.5\,d)$. Early-type and late-type EW binaries follow opposite trends in $\rm T_{eff}$ with orbital period. For longer periods, early-type EW binaries are cooler, while late-type systems are hotter. We derive period-luminosity relationships (PLRs) in the $W_{JK}$, $V$, Gaia DR2 $G$, $J$, $H$, $K_s$ and $W_1$ bands for the late-type and early-type EW binaries separated both by period and effective temperature, and by period alone. The dichotomy of contact binaries is almost certainly related to the Kraft break and the related changes in envelope structure, winds and angular momentum loss. Accepted by MNRAS |
| Databáze: | OpenAIRE |
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