English

On the Nonspherical Nature of Halo Formation

Astrophysics 2009-10-31 v2

Abstract

We present a new collapse condition to describe the formation of dark halos via nonspherical gravitational clustering. This new nonspherical collapse condition is obtained by the logical generalization of the spherical model to the nonspherical one. By solving a diffusion-like random matrix equation with the help of the Monte Carlo method, we show that this nonspherical collapse condition yields the mass function derived by Sheth & Tormen (1999) which has been shown to be in excellent agreement with the recent N-body results of high resolution. We expect that this nonspherical collapse condition might provide us a deeper insight into the structure formation, and suggest that it should be widely applied to various cosmological issues such as the galaxy merging history, the galaxy bias, and so forth.

Keywords

Cite

@article{arxiv.astro-ph/0010286,
  title  = {On the Nonspherical Nature of Halo Formation},
  author = {Tzihong Chiueh and Jounghun Lee},
  journal= {arXiv preprint arXiv:astro-ph/0010286},
  year   = {2009}
}

Comments

Accepted version, ApJ in press, LaTex file, 1 ps figure, mistakes and typos corrected