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.
Send comments/suggestions/problems to robb@
uvic.ca