Multiperiodicity and physical nature of the π Sct star GSC 2683-3076

We present the results of a CCD Johnson V and photoelectric Stromgren uvbyβ photometric study of the recently discovered multiperiodic δ Sct star GSC 2683-3076. Our data set mainly consists of 2874 differential measurements in V together with a few data collected into the uvbyβ system. Additional unfiltered CCD measurements were also carried out. A set of seven best-fitting pulsation frequencies representing the light variations of the variable has been detected. The spectral type of the variable is found to be A9V or F0V. Using the uvbyβ indices the following main physical parameters for the variable have been derived: Teff=7230 K, MV=1.95 mag, log g=3.90, M=1.85 M⊙, R=2.30 R⊙, ρ=0.16 ρ⊙, age =1.0 Gyr, metal abundance [Me/H]=0.16 and distance modulus =8.4 mag. GSC 2683-3076 is found to be a Population I δ Sct star, slightly metal-enriched, evolving on its main-sequence stage. A mixture of radial and non-radial modes seems to be present in the pulsation of this variable. This star is also known as H133 in the young open cluster NGC 6871, however arguments are given that address this star as a non-member of the cluster. The uvbyβ photometry available in the literature for NGC 6871 is also discussed.