Limits in the application of harmonic analysis to pulsating stars
1
Instituto de Astrofísica de Andalucía (CSIC),
18008
Granada,
Spain
e-mail: javier@ugr.es; garrido@ugr.es; jcsuarez@ugr.es
2
Dept. Física Teórica y del Cosmos. Universidad de
Granada, 18071
Granada,
Spain
Received: 29 December 2014
Accepted: 4 July 2015
Using ultra-precise data from space instrumentation, we found that the underlying functions of stellar light curves from some AF pulsating stars are non-analytic, and consequently their Fourier expansion is not guaranteed. This result demonstrates that periodograms do not provide a mathematically consistent estimator of the frequency content for this type of variable stars. More importantly, this constitutes the first counterexample against the current paradigm, which considers that any physical process is described by a continuous (band-limited) function that is infinitely differentiable.
Key words: asteroseismology / methods: data analysis / stars: oscillations
© ESO, 2015