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The recent analyses of the light curves provided by CoRoT have revealedpulsation spectra of unprecedented richness and precision, in particular,thousands of pulsating modes, and a clear distribution of amplitudes withfrequency. In the community, some scientists have started doubting about thevalidity of the classical tools to analyze these very accurate light curves.  This work provides the asteroseismic community with answers to this questionshowing that (1) it is physically possible for a star to excite at a time andwith the observed amplitudes such a large number of modes; and (2) that thekinetic energy accumulated in all those modes does not destroy the equilibriumof the star. Consequently, mathematical tools presently applied in the analysesof light curves can a priori be trusted. This conclusion is even more importantnow, when a large amount of space data coming from Kepler are currently beinganalyzed.  The power spectrum of different stellar cases, and the non-adiabatic codeGraCo have been used to estimate the upper limit of the energy per secondrequired to excite all the observed modes, and their total kinetic energy. Anecessary previous step for this study is to infer the relative radialpulsational amplitude from the observed photometric amplitude, scaling ourlinear pulsational solutions to absolute values. The derived upper limits forthe required pulsational energy were compared with 1) the luminosity of thestar; and 2) the gravitational energy. We obtained that both upper energylimits are orders of magnitude smaller.

Has a star enough energy to excite the thousand of modes observed with CoRoT?