Energy Lost by a Particle Beam in a Lossy Coaxial Liner with Many Holes

In the framework of Bethe's modified theory we study the energy lost by a relativistic particle beam travelling in a coaxial liner with many holes, including the effect of attenuation in the coaxial r egion. The interference among the holes is the main source of losses and is affected by the attenuation in the coaxial only on sufficiently long distances. We derive analytical formulae for all the in teresting quantities and a particular attention is given in clarifying the physical meaning; numerical examples are considered using the LHC nominal parameters.