The excitation rate P at which solar like oscillations are excited depends on the magnitude and depth dependence of the convective velocity w(r) within the upper part of the convective zone of low massive stars 1 < M < 2 M_\odot$. Theoretical estimations of w(r) in the excitation region using a mixing-length phenomenological approach crucially depends on the adopted formulation.
In the present work we therefore compare the effects on P of using different local convection formulations: the classical mixing-length theory (CMLT) and the formulation of Canuo et al (1996) which takes into account contributions to the convective flux of turbulent elements with different sizes.
The computation of P is based on a theoretical model of stochastic exitation where the static and dynamic properties of turbulent convection are constrained by results of 3D simulations (Samadi et al 2002, in preparation).
The excitation rate is calculated for a solar model and several models with larger masses and different effective temperatures, build with the CMLT and the CGM, so as to scan the relevant region of the HR diagram. We compare the present results with our previous ones obtained with the non-local formulation of the MLT by Gough (1976, 1977). Our results illustrate the strong constraints, measurements of P can provide on the convection treatment to implement in an equilibrium model.
 
Canuto, V. M., Goldman, I., & Mazzitelli, I. 1996, ApJ, 473, 550
Gough, D. 1976, in Lecture notes in physics, Vol. 71, Problems of stellar convection, ed. E. Spiegel & J.-P. Zahn (Springer Verlag), 15
Gough, D. O. 1977, ApJ, 214, 196

 
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