• CERN AD Target core hydrocode Modal Finite Element

Antiprotons, like many other exotic particles, are produced by impacting high energy proton beams onto fixed targets. At the European Organization for Nuclear Research (CERN), this is done in the Antiproton Decelerator (AD) Facility.
The engineering challenges related to the design of an optimal configuration of the AD-Target system derive from the extremely high energy depositions reached in the very thin target core as a consequence of each proton beam impact. A new target design is foreseen for operation after 2021, triggering multiple R&D activities since 2013 for this purpose. The goal of the present Master Thesis is to complement these activities with analytical and numerical calculations, delving into the phenomena associated to the dynamic response of the target core. In this context, two main studies have been carried out. First, the experimental data observed in targets subjected to low intensity proton pulses was cross-checked with analytical and computational methods for modal analysis, applied under the assumption of completely elastic responses of the material. The analysis then focused on the flexural modes of vibration of the rods, excited by off-axis proton beam impacts. In the second part, hydrocode simulations of the response of two potential prototypes for the future AD-Target core are presented. For a deep understanding of the phenomena governing the dynamic response of the target core in operation, the simulations were performed gradually increasing the complexity of the models. The results of the analysis were finally applied to quantify and understand the effects of changes of the core geometry on its dynamic response and tensile pressures reached.