Segregation of heavy elements in an initial protoplanet

In this paper, we present a calculation for settling times of grains falling under the action of the gravitational field inside a Jupiter mass protoplanet formed via disk instability, where the grains are assumed to be grown by the process of cold welding. As the energy equation, we have considered the conductive-radiative case of heat transport. In our calculation, we have not used any density model, rather, we have estimated the distribution of physical variables inside the protoplanet. With the obtained distribution of the physical variables, we have investigated the growth of the grains having different initial radii (5 × 10 −3 - 10 −1 cm) and hence calculated their sedimentation times. The results are found to be in good agreement with those obtained in other investigations.

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