During 3 consecutive nights, 13 southern Fand Gtype dwarfs and giants outside the conventional δ Scuti instability strip were observed at high spectral (3 km/s) and medium temporal (10-15 min) resolution. The stars were selected for their reported broad spectral lines (v sin i≥ 40 km/s) so that pulsation in higher azimuthal-order nonradial harmonics could, via the rotational Doppler effect, rev...

The δ Scuti star X Caeli has been the target of a simultaneous photometric (14 consecutive nights) and spectroscopic campaign (8 consecutive nights). From the analysis of light curves we were able to pick up 17 frequency components, most of which were already detected in two previous campaigns. The comparison with the results of the previous campaigns shows that while some terms are rather stab...

The δ Scuti star X Caeli has been the target of a simultaneous photometric (14 consecutive nights) and spectroscopic campaign (8 consecutive nigths). From the analysis of light curves we were able to pick up 17 frequency components, most of which were already detected in two previous campaigns. The comparison with the results of the previous campaigns shows that while some terms are rather stab...

We discuss observations and seismic analyses for three multi-periodic δ Scuti stars in the Praesepe cluster: BU, BN and BV Cnc. For two stars (BU and BN Cnc) we re-analyse published photoelectric photometry and show that using statistical weights results in a dramatic reduction in the noise level. We detect seven frequencies in BU Cnc and eight in BN Cnc, with three of the latter being previous...

Phase differences and amplitude ratios at different colour photometric bands are currently being used to discriminate pulsation modes in order to facilitate mode identification of κ-driven non-radial pulsating stars. In addition to physical inputs (e.g., mass, T e f f , etc.), these quantities depend on the non-adiabatic treatment of the atmosphere. This paper presents theoretical results conce...