CORSIKA Based Simulations of Background in Baikal Experiment

The Baikal experiment aims to register cosmological neutrinos and map the high-energy neutrino sky in the Southern Hemisphere including the region of the Galactic Center. It will use a km³-scale high-energy neutrino telescope located in the southern basin of the Lake Baikal. The northern location of the detector site allows direct observation of the Galactic Center in more than 75 % of the astronomical time. The selection of events from neutrino induced upward going muons, suggests a fairly reliable estimation of the expected background from atmospheric muons. The procedure for simulating background events from atmospheric muons in an array is performed in several steps. The CORSIKA 7.64 was used to simulate the flux of atmospheric muons at the sea level with appropriate chemical composition of the primary cosmic rays. The muon propagation through water and rock to the array level was then simulated with the MUM code. As the last step of the simulation chain, the detector response to the Cherenkov radiation of muons was estimated by taking into account the features of the array measuring systems was performed. The main features of the CORSIKA Monte Carlo code and the next steps of the simulation chain are summarized. The physical models embedded in CORSIKA are described. Application of the full simulation chain is demonstrated.