Searches for rapid line profile variations of two pulsating CP2 stars: HD 128898 and HD 201601

Abstract

Neither for Equ nor for αCir was clear positive evidence present for spectral variations which could be attributed to non-radial pulsation. However, our instrumentation was just at the limit of what would be required for a detection of the subtle effects which can be expected for the pulsating CP2 stars. A spectral resolution at least twice as high as that presently used should be attempted for future investigations, as well as a considerable improvement of the SIN ratio of the individual spectra. Obviously, telescopes of the 3 m class and larger are required for such observations, even if the program stars are very bright.

Based in part on observations collected at the European Southern Observatory, La Silla, Chile, with the financial support of the Austrian “Fonds zur Förderung der wissenschaftlichen Forschung”, project No.4170. TJK and APO were visiting astronomers, Kitt Peak National Observatory, which is operated by AURA, under contract with the National Science Foundation.