Speaker: Pierluigi Monaco

Though the progress in N-body codes has made it possible to perform huge simulations of large-scale structure, the production of simulated galaxy catalogs that reproduce the properties of forthcoming surveys like Euclid is still a challenge. I will present the characteristics and performance of the new version of the code called PINpointing Orbit Crossing Collapsed HIerarchical Objects (PINOCCHIO), able to generate catalogs of DM halos with known mass, position, velocity and merger history, in a fraction of the time required by a simulation with the same number of particles. PINOCCHIO is an extension of the excursion set approach, and is based on Lagrangian Perturbation Theory (LPT). Its accuracy has been tested by many groups, and because halos are reconstructed in the Lagrangian space, its predictions on clustering are limited mostly by the use of LPT to compute the displacements. Recent code development has allowed to scale the code up to tens of thousands of cores, and to produce very large boxes, with several 10^10 particles, in less then an hour. With this tool, tasks like a brute-force approach to compute the covariance matrix of 2-point clustering statistics, can be feasible.