Three-point correlation function in the quasilinear regime.

Using the second-order Eulerian perturbation theory (SEPT), we study the three-point correlation function in the quasilinear regime for the SCDM, LCDM and MDM models, with the interesting result that these three models have distinc- tive three-point correlation functions. We test this SEPT pre- diction using a large set of high-resolution N-body simulations. The N-body results show that the SEPT prediction for is not accurate even in the quasilinear regime (r < 10h 1 Mpc), in contrast to previous N-body tests on the skewness. However, similar to the perturbation theory, our N-body results still pre- dict a strong dependence of the three-point correlation on the triangleshapewhichisobservableinthedistributionofgalaxies if the galaxies trace the distribution of the underlying mass