  Asymmetric features in exoplanet transit light curves are often interpreted
as a gravity darkening effect especially if there is spectroscopic evidence of
a spin-orbit misalignment. Since other processes can also lead to light curve
asymmetries this may lead to inaccurate gravity darkening parameters. Here we
investigate the case of non-radial pulsations as possible sources of asymmetry
and likely source of misinterpreted parameters through simulations. We obtained
a series of simulated transit light curves of a hypothetical exoplanet-star
system: a host star with no gravity darkening exhibiting small amplitude
pulsations, and a typical hot Jupiter in a circular, edge-on orbit. A number of
scenarios of pulsations of various amplitudes were considered, and a proper
account of the obscuring effect of transits on all the surface intensity
components was made. The magnitude of amplitude and phase modulations of
nonradial pulsations during transits was also also investigated. We then fitted
both a non-gravity-darkened, and a gravity-darkened, free spin-orbit axis model
on the data. The Akaike and Bayesian Information Criteria were used for an
objective selection of the most plausible model. We then explored the
dependence of the parameter deviations on the pulsation properties, in order to
identify configurations that can lead to falsely misaligned solutions.
Low-amplitude pulsations in general do not affect the determination of the
system parameters beyond their noise nature. However, frequencies close to
multiples of the orbital frequency are found to cause distortions leading to
solutions with a side tilted stellar rotational axis, they are therefore
preferable to clean beforehand for the sake of a correct analysis.
Additionally, for cases with higher-amplitude pulsations, it is recommended to
pre-process and clean the pulsations before analysis.
