Probable nonradial g-mode pulsation in early A-type stars

Abstract

A survey for line profile variability in early A-type stars has been performed in order to detect nonradial pulsation signatures. The star HR 6139, with spectral type A2V and estimated T_eff=8800 K, shows evident line profile variations that can be explained by oscillations in prograde g-modes. This feature and the known photometric variability are similar to those observed in the Slowly Pulsating B-type stars. However HR 6139 is much cooler than the cool border of the instability strip of such variables, and it is hotter than the blue edge of the delta Scuti instability strip. There are indications of a tiny variability also in other four objects, whose nature is not yet clear.

arXiv comment4 pages, 5 figures; accepted for publication in A&A (letter)

References in corpus (5)

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Cited by in corpus (4)

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• The hot Gamma-Doradus and Maia stars
• Seismic evolution of low/intermediate mass PMS stars