A study of correlation between the oscillation amplitude and stellar parameters of δ Scuti stars in open clusters

Toward selection rules for δ Scuti star oscillations

¹ LESIA, Observatoire de Paris-Meudon, FRE 2461, France e-mail: Eric.Michel@obspm.fr
² Instituto de Astrofísica de Canarias (IAC), 38200 La Laguna, Tenerife, Spain e-mail: fph@ll.iac.es; lfox@ll.iac.es
³ Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain
⁴ GEPI, Observatoire de Paris-Meudon, FRE 2459, France e-mail: Yveline.Lebreton@obspm.fr
⁵ National Astronomical Observatories, Chinese Academy of Sciences, 100012 Beijing, PR China e-mail: lizhi@bao.ac.cn

Corresponding author: J.-C. Suárez, JuanCarlos.Suarez@obspm.fr

Received: 6 March 2002
Accepted: 3 April 2002

Abstract

In the present work, we study correlations between stellar fundamental parameters and the oscillation amplitude for δ Scuti stars. We present this study for a sample of 17 selected δ Scuti stars belonging to 5 young open clusters. Taking advantage of properties of δ Scuti stars in clusters, we correct the photometric parameters of our objects for the effects of fast rotation. We confirm the benefit of applying such corrections in this kind of studies. In addition, the technique used for this correction allows us to obtain an estimate of stellar parameters such as the angle of inclination and the rotation rate, usually not accessible. A significant correlation between the parameter (estimation of the angle of inclination of the star) and the oscillation amplitude is found. A discussion and interpretation of these a priori surprising results is proposed, in terms of a possible selection rule for oscillation modes of δ Scuti stars.