2011A&A...531A.124B

Kepler produces a large amount of data used for asteroseismological analyses, particularly of solar-like stars and red giants. The mode amplitudes observed in the Kepler spectral band have to be converted into bolometric amplitudes to be compared to models. We give a simple bolometric correction for the amplitudes of radial modes observed with Kepler, as well as the relative visibilities of non-radial modes. We numerically compute the bolometric correction c_K–bol and mode visibilities for different effective temperatures T_eff within the range 4000-7500 K, using a similar approach to a recent one from the literature. We derive a law for the correction to bolometric values: c_K–bol=1+a₁(T_eff-T_o)+a₂(T_eff-T_o)², with T_o=5934 K, a₁=1.349x10^–4 K^–1, and a₂=-3.120x10^–9 K^–2 or, alternatively, as the power law c_K–bol=(T_eff/T_o)^α with α=0.80. We give tabulated values for the mode visibilities based on limb-darkening (LD), computed from ATLAS9 model atmospheres for T_effin[4000, 7500] K, logg in[2.5, 4.5], and [M/H] in[-1.0,+1.0]. We show that using LD profiles already integrated over the spectral band provides quick and good approximations for visibilities. We point out the limits of these classical visibility estimations.