[View Abstracts by Session]

Session: Stars, Planets and the Interstellar Medium

Name: Prof. Michael Contadakis (Aristotle University of Thessaloniki)
Coauthors: No coauthors were included.
Type: Poster
Title: Starquakes on the Flare stars.
Abstract:

Flare stars have been subjected to extending research for many decades at the Stefanion Observatory. Apart of the spectacular flaring phenomena, the results of the analysis of the one colour (B) observations of the Stefanion Observatory at any stage of their activity (quiescence, weak flares, strong flares),indicate that: (1) Transient high frequency oscillations occur during the flare event and during the quiet-star phase as well; (2) The Observed frequencies range between 0.0005Hz (period 33min) and 0.3 Hz (period 3s) not rigorously bounded.. It is interesting that transient oscillations appear also far apart from the observed flares, during the quiet state of the stars, as a result of the general magnetic activity of the star. This fact led us to examine the existence of starquakes on Flare stars. Thus we examine the power spectrum of the Flare stars and we find that they resample that of the solar like oscillation spectra i.e the sunquake spectra. Our tentative analysis of our observations shows that we observe starquakes on Flare stars similar to that of a red subgiant.

Co-authors:J.H. Seiradakis2, S.J. Avgoloupis2, Ch. Papantoniou1
1Department of Surveying and Geodesy, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece
2Session of Astronomy, Astrophysics and Mechanics, Department of Physics, Scool of Sciences, Aristotle University of Thessaloniki, GR-54124, Thessaloniki, Greece.
Keywords: Flare stars-Starquakes, Discrete Fourier Transform analysis -Brownian Walk noise