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arXiv · 1705.05302

Why does Einasto profile index $n\sim 6$ occur so frequently?

Anton N. Baushev·Maxim V. Barkov
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Abstract

We consider the behavior of spherically symmetric Einasto halos composed of gravitating particles in the Fokker-Planck approximation. This approach allows us to consider the undesirable influence of close encounters in the N-body simulations more adequately than the generally accepted criteria. The Einasto profile with index $n \approx 6$ is a stationary solution of the Fokker-Planck equation in the halo center. There are some reasons to believe that the solution is an attractor. Then the Fokker-Planck diffusion tends to transform a density profile to the equilibrium one with the Einasto index $n \approx 6$. We suggest this effect as a possible reason why the Einasto index $n \approx 6$ occurs so frequently in the interpretation of N-body simulation results. The results obtained cast doubt on generally accepted criteria of N-body simulation convergence.

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Anton N. Baushev, Maxim V. Barkov. 2017-05-15. Why does Einasto profile index $n\sim 6$ occur so frequently?. https://doi.org/10.1088/1475-7516%2F2018%2F03%2F034

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