• P. Lebrun
  CERN, Geneva
• P.H. Garbincius
  Fermilab, Batavia

High-energy accelerators are large projects funded by public money, developed over the years and constructed via major industrial contracts both in advanced technology and in more conventional domains such as civil engineering and infrastructure, for which they often constitute one-off markets. Assessing their cost, as well as the risk and uncertainty associated with this assessment is therefore an essential part of project preparation and a justified requirement by the funding agencies. Stemming from the experience with large circular colliders at CERN, LEP and LHC, as well as with the Main Injector, the Tevatron Collider Experiments and Accelerator Upgrades, and the NOvA Experiment at Fermilab, we discuss sources of cost variance and derive cost risk assessment methods applicable to the future linear collider, through its two technical approaches for ILC and CLIC. We also address disparities in cost risk assessment imposed by regional differences in regulations, procedures and practices.

• D. Schulte, R. Corsini, B. Dalena, J.-P. Delahaye, S. Döbert, G. Geschonke, A. Grudiev, J.B. Jeanneret, E. Jensen, P. Lebrun, Y. Papaphilippou, L. Rinolfi, G. Rumolo, H. Schmickler, F. Stulle, I. Syratchev, R. Tomás, W. Wuensch
  CERN, Geneva
• E. Adli
  University of Oslo, Oslo

The physics experiments at CLIC will require that the machine scans lower than nominal centre-of-mass energy. We present different options to achieve this and discuss the implications for luminosity and the machine design.

• P. Lebrun, P. Spentzouris
  Fermilab, Batavia
• J.R. Cary
  CIPS, Boulder, Colorado
• P. Stolz, S.A. Veitzer
  Tech-X, Boulder, Colorado

Precision simulations of the electron cloud at the Fermilab Main Injector have been studied using the plasma simulation code VORPAL. Fully 3D and self consistent solutions that includes Yee-type E.M. field maps generated by the cloud and the proton bunches have been obtained, as well detailed distributions of the 6D phase space occupied by the electrons. We plan to include such maps in the ongoing simulation of the space charge effects in the Main Injector. Simulations of the response of retarded field analyzers and microwave transmission experiments are ongoing.