High-Resolution Simulation of Deep Pencil Beam Surveys

Abstract

We report on a recent paper (Weiß \& Buchert 1993), where we carry out pencil beam constructions in a high-resolution simulation of the large-scale structure of galaxies. As an example we present the results for the case of ``Hot-Dark-Matter" (HDM) initial conditions (with scale-free $n = 1$ power index on large scales and $Ω= 1$) as a representative of models with sufficient large-scale power. We use an analytic approximation for particle trajectories of a self-gravitating dust continuum and apply a local dynamical biasing of volume elements to identify luminous matter in the model. Using this method, we are able to resolve formally a simulation box of 1200h^-1 Mpc (e.g. for HDM initial conditions) down to the scale of galactic halos using $2160^3$ particles. Pencil beam probes are taken for a given epoch using the parameters of observed beams. In particular, our analysis concentrates on the detection of a quasi-periodicity in the beam probes. The simulation is designed for application to parameter studies which prepare future observational projects. We find that a large percentage of the beams shows quasi-periodicities with periods which cluster at a certain length scale. The periods found range between one and eight times the cutoff length in the initial fluctuation spectrum.