Comparison of Analytical Mass Functions with Numerical Simulations

Research paper by Jounghun Lee, Sergei F. Shandarin

Indexed on: 23 Mar '99Published on: 23 Mar '99Published in: Astrophysics


We present numerical testing results of our mass function derived in our previous paper, and compare the testing results with those of the popular Press-Schechter (PS) mass function. Two fiducial models are considered for the test: the scale-free power-law spectra P(k) \propto k^{n} with spectral indices n=-1, 0 and the standard cold dark matter (SCDM) model with Omega =1 and h=0.5. For the power-law models, we use numerical data averaged over several different output times: ten output times from two N-body realizations for the n=-1 power-law model; four outputs from one realization for the n=0 model. While for the SCDM model, we consider four outputs separately at redshifts z = 0, 0.43, 1.14 and 1.86 from one large N-body simulations. The comparison results show that our mass function fits the numerical data in a much improved way over the PS one. Thus, we expect that our mass function can be a viable alternative of the PS mass function in applications to various areas.