generation linear colliders

We have studied the structural damage of W-Re targets produced by electrons with energies of several GeV and under different conditions of total number of electrons, beam shape and target depth. We report the differences in damage levels for different designs considered in the construction of the next generation of linear accelerators, and discuss the possible effects in the lifetime of these targets. Due to the complexity of the problem, which requires following the trajectory of GeV electrons down to eV energies, this work utilized different simulation tools, from Monte Carlo codes of hadronic and electromagnetic interactions such as FLUKA, to molecular dynamics simulations of defect production. Our work shows that the final defect production depends not only on