Bibcode
Régulo, C.; Roca Cortés, T.
Bibliographical reference
Astronomy and Astrophysics, Volume 444, Issue 1, December II 2005, pp.L5-L8
Advertised on:
12
2005
Journal
Citations
18
Refereed citations
15
Description
Recently, Matthews et al. (2004, Nature, 430, 51) claim a null detection
of p-mode oscillations in Procyon A from 32 days of nearly continuous
photometric satellite-based observations (MOST). They did not even find
evidence in the Fourier amplitude spectrum of Procyon of the uniform
frequency spacing signature that solar-like stars acoustic spectrum must
show according to asymptotic theory. However, re-analysing his data, we
have found a clear evidence of signal fully compatible with what is
expected from p-mode oscillations in Procyon A. Using the method
developed in Régulo & Roca Cortés (2002, A&A, 396,
745), that allows the analysis of stellar oscillations in the acoustic
power spectrum of solar-like stars when the signal is buried in noise,
we have found a frequency spacing in the power spectrum of the data of
54.5 μHz, that agrees well with the expectations of the theory of
stellar oscillation as well as with previous estimations from
ground-based observations. Moreover, our method allows the recovery of
the power spectrum of the signal from the knowledge of the frequency
spacing present in the data, which yields clear peaks that can be
identified as acoustic p-modes. Nonetheless, as the frequency spacing
coincides with the second sub-multiple of the orbital frequency of the
satellite (164.34 μHz) the above findings must be taken with caution.