Astron. Astrophys. Suppl. Ser. 135, 547-553
The multiperiodic Scuti star 4 Canum Venaticorum: 1997 APT photometry
M. Breger - F. Hiesberger
Send offprint request: M. Breger
Astronomisches Institut der Universität Wien, Türkenschanzstr. 17, A-1180 Wien, Austria e-mail: firstname.lastname@example.org
Received November 2; accepted November 30, 1998
204 hours of high-quality measurements of 4 CVn during 32 nights were obtained with the 0.75 m Automatic Photolectric Telescope (APT). The two comparison stars measured agreed to 2.7 mmag per single measurement in Stromgren y and 3.0 mmag in v. It is shown that APT's can be used successfully for the study of stellar nonradial pulsation at the millimag level.
An analysis of the multiperiodicity of 4 CVn revealed the presence of 19 simultaneously excited pulsation frequencies. This presents a considerable increase from the 7 frequencies found during a previous campaign of the Delta Scuti Network. The previously known frequencies were confirmed with amplitude variability on a time scale of years.
Key words: stars: Sct -- stars: oscillations -- stars: individual: 4 CVn -- techniques: photometric