Photometric observations of the cataclysmic variable star IP Peg Rakutou High School Kasumi Goto Ayano Terada

The history of Our observations 60cm telescope of HIDA observatory, September 23th of cm telescope of HIDA observatory, September 23th of cm telescope of Kyoto University s roof observatory, November 22nd of cm telescope of Kyoto University s roof observatory, November 22nd of 2005 these clouded when eclipse. these clouded when eclipse. December 23rd of 2006 December 23rd of 2006 light curve light curve inclination angle of orbit inclination angle of orbit angle of Hotspot with Companion angle of Hotspot with Companion Couldn t observe!!

The system of CVs Central star Compact Star with Accretion Disc. Companion (red giant) Hot Spot Where gas flow on Accretion Disk The orbital period typically several hours

Observation Automatic observation exposure time 30 sec. Dec 23rd of 2006, JT 18:53~21:25. The 40cm telescope at Kyoto University roof observatory.

Analysis IRAF software at Kyoto university Makali`i (Subaru image processing software) at school. We obtained stellar magnitudes.

The light curve simulation Using IDL system At Department of Astronomy, Kyoto University The inclinations The angles of Hot Spot with companion simulation Simulation code is made by Mr. Sugiyasu.

companion Accretion Disc Line of sight Inclination Revolution axis Surface of revolution orbit

Relationship of the companion star and the accretion disk, and Hot spot Hot Spot Companion Accretion Disc

Ordinate: magnitude Abscissa: time (hours) The influence by the companion center of eclipse Factor point Beginning of cloudy The light curve

The inclination is 85° The angle of Hot Spot with the companion is 25° The simulation light curve

The inclination is 90° The angle of the Hot Spot with the companion is 25°

Result The inclination is 85° The angle of the Hot Spot with the companion is 25°

Acknowledgment We thank staff of Department of Astronomy, Kyoto University.