Modeling Future Hadron Colliders’ Availability for Physics

This thesis presents an availability model for the Future Circular hadron Collider. The model is based on the current operations of the Large Hadron Collider. The thesis shows that hadron collider’s availability for physics is a complex problem as it depends both on the system availability and the operational cycle. The availability itself is not the key performance indicator but it is closely linked to collision production and so-called integrated luminosity that are essential for physics research. The thesis shows that taking into account the operational cycle is critical for modeling luminosity production. The thesis validates the model against LHC operations and shows preliminary results on the FCC availability and luminosity production. Ramentor Oy’ ELMAS software was chosen as the platform for the model. ELMAS is designed as a fault tree software. However, the developed model combines fault trees with Markov models. This feature was implemented by adding custom Java code and libraries to models. This reliance on a custom code was not the ideal solution and lead to the development of the OpenMARS approach. This approach allows combining the most common risk assessment and operation modeling techniques and connecting the models made with these techniques. This thesis presents the basic concept of this approach and shows how the collider operations model can be implemented with it. The discussion section also provides ideas on how the study would have proceeded if the collaboration with Ramentor Oy had not been an option and further applications of the OpenMARS approach. Another issue encountered during the study was the lack of reliability data. This issue resulted in a study of reliability data sharing practices in the industry where the author was a key contributor. The thesis presents the idea to use a similar concept in the accelerator field and comments on this.