Eclipsing Binaries

Comm42 Bibliography of Close Binaries

The Eclipsing Binary System ER Vulpeculae

Light Curve of the star ER Vul Aug/Sep 2002.
This is the light curve of the famous eclipsing binary star ER Vul. It is composed of two stars very similar to the sun but which orbit each other with a period of 0.69809409 days ~17 hours. The different colors are for different coloured filters we used B=blue V=yellow, R=red and I=infrared.
We can calculate what the brightness of the star system will be as the stars orbit each. The width of the eclipses are determined by the radii of the stars. The depth of the eclipses are set by the inclination of the orbit. The ratio of the depths of the eclipses is governed by the ratio of the temperatures of the two stars.

This is a fit to the infrared light curve. Radii of 0.30 and 0.28; Temperatures of 6300 and 6000K; inclination i=65.8. We have added a star spot which is 93% of the photospheric temperature at a longitude of 225 and latitude of 22 South and a diameter of 18 degrees to make the second maximum asymmetric.

This is a fit to the red measurements. Same radii and temperature but an inclination of 65.4.

This is a fit to the yellow (=V) observations. Same radii and temperature but an inclination of 65.4. All the fits were done using Bradstreet's BINMAKER program. These values are similar to those found by Ekmekci (2001) namely Radii of .28 and .30, temperatures of 5900 and 5500K, and inclination of 66 degrees.

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