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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

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Selected Works

2018

Binaries: eclipsing

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

The Strange Evolution Of The Large Magellanic Cloud Cepheid Ogle-Lmc-Cep1812, Hilding R. Neilson, Robert G. Izzard, Nobert Langer, Richard Ignace Aug 2018

The Strange Evolution Of The Large Magellanic Cloud Cepheid Ogle-Lmc-Cep1812, Hilding R. Neilson, Robert G. Izzard, Nobert Langer, Richard Ignace

Richard Ignace

Classical Cepheids are key probes of both stellar astrophysics and cosmology as standard candles and pulsating variable stars. It is important to understand Cepheids in unprecedented detail in preparation for upcoming Gaia, James Webb Space Telescope (JWST) and extremely-large telescope observations. Cepheid eclipsing binary stars are ideal tools for achieving this goal, however there are currently only three known systems. One of those systems, OGLE-LMC-CEP1812, raises new questions about the evolution of classical Cepheids because of an apparent age discrepancy between the Cepheid and its red giant companion. We show that the Cepheid component is actually the product of a …


Lp 133-373: A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, Todd R. Vaccaro, A. Kawka, T. D. Oswalt, I. Silver, M. Wood, J. Allyn Smith Jun 2018

Lp 133-373: A New Chromospherically Active Eclipsing Dme Binary With A Distant, Cool White Dwarf Companion, Todd R. Vaccaro, A. Kawka, T. D. Oswalt, I. Silver, M. Wood, J. Allyn Smith

Terry D. Oswalt

We report the discovery of the partially eclipsing binary LP 133-373. Nearly identical eclipses along with observed photometric colors and spectroscopy indicate that it is a pair of chromospherically active dM4 stars in a circular 1.6 day orbit. Light and velocity curve modeling to our differential photometry and velocity data show that each star has a mass and radius of 0.340+/-0.014 Msolar and 0.33+/-0.02 Rsolar. The binary is itself part of a common proper motion pair with LP 133-374, a cool DC or possible DA white dwarf with a mass of 0.49-0.82 Msolar, which would …