Beam impact studies on ILC collimators

Spoilers in the ILC Beam Delivery System are required to survive without failure a minimum of 1-2 direct impacts from each energetic electron or positron bunch of charged particles, in addition to maintaining low geometric and resistive wall wake fields. The transient shock wave resulting from rapid localised beam heating and its implications for spoiler design are studied using ANSYS. Shockwave propagation is modelled in 2 dimensions showing the effect of dilatational Shockwaves striking free surfaces, producing reflected dilatational and distortional waves. The implication of these reflected waves on the damage of the collimators is also discussed.