  Atmospheric muons play an important role in underwater/ice neutrino
detectors. In this paper, a parameterisation of the flux of single and multiple
muon events, their lateral distribution and of their energy spectrum is
presented. The kinematics parameters were modelled starting from a full Monte
Carlo simulation of the interaction of primary cosmic rays with atmospheric
nuclei; secondary muons reaching the sea level were propagated in the deep
water. The parametric formulas are valid for a vertical depth of 1.5-5 km w.e.
and up to 85 deg for the zenith angle, and can be used as input for a fast
simulation of atmospheric muons in underwater/ice detectors.
