• J. Resta-López, J. Dale
  JAI, Oxford
• B. Dalena, D. Schulte, J. Snuverink, F. Stulle, R. Tomás
  CERN, Geneva
• A. Latina
  Fermilab, Batavia

We present the current status of the beam tracking simulations of the Compact Linear Collider (CLIC) from the exit of the damping ring to the interaction point, including the ring to main linac (RTML) section, main linac, beam delivery system (BDS) and beam-beam interactions. This model introduces realistic alignment survey errors, dynamic imperfections and also the possibility to study collective effects in the main linac and the BDS. Special emphasis is put on low emittance transport and beam stabilization studies, applying beam based alignment methods and feedback systems. The aim is to perform realistic integrated simulations to obtain reliable luminosity predictions.

• J. Resta-López
  JAI, Oxford
• D. Angal-Kalinin, J.-L. Fernandez-Hernando, F. Jackson
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• B. Dalena, D. Schulte, R. Tomás
  CERN, Geneva
• A. Seryi
  SLAC, Menlo Park, California

Important efforts have recently been dedicated to the improvement of the design of the baseline collimation system of the Compact Linear Collider (CLIC). Different aspects of the design have been optimized: the transverse collimation depths have been recalculated in order to reduce the collimator wakefield effects while maintaining a good efficiency in cleaning the undesired beam halo; the geometric design of the spoilers have also been reviewed to minimize wakefields; in addition, the optics design have been polished to improve the collimation efficiency. This paper describes the current status of the CLIC collimation system after this optimization.

• 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.

• B. Dalena, D. Schulte
  CERN, Geneva

Beam-Beam background is one of the main issues of the CLIC MDI at 3 TeV CM. The background level have a significant impact on the interaction region design. This paper presents a study of the background expected rates versus luminosity according to different beam parameters and considering different machine conditions, using an integrated simulation of the Main LINAC and BDS sub-systems.

• R. Tomás, B. Dalena, J. Pfingstner, D. Schulte, J. Snuverink
  CERN, Geneva
• J.K. Jones
  Cockcroft Institute, Warrington, Cheshire
• A. Latina
  Fermilab, Batavia
• J. Resta-López
  JAI, Oxford

The CLIC BDS tuning, alignment and feedbacks studies have been typically performed independently and only over particular sections of the BDS. An effort is being put to integrate all these procedures to realistically evaluate the luminosity performance.

• B. Dalena, D. Schulte, R. Tomás
  CERN, Geneva

The main detector solenoid and associated magnets can have an important impact on the CLIC luminosity. These effects are discussed for different solenoid designs. In particular, the luminosity loss due to incoherent synchrotron radiation in the experiment solenoid and QD0 overlap is evaluated. The impact of the AntiDiD (Anti Detector integrated Dipole) on luminosity and compensated techniques on beam optic distortion are also discussed.

• R. Tomás, B. Dalena, E. Marin, D. Schulte, G. Zamudio
  CERN, Geneva
• D. Angal-Kalinin, J.-L. Fernandez-Hernando, F. Jackson
  Cockcroft Institute, Warrington, Cheshire
• J. Resta-López
  JAI, Oxford
• A. Seryi
  SLAC, Menlo Park, California

The CLIC Conceptual Design Report must be ready by 2010. This paper aims at addressing all the critical points of the CLIC BDS to be later implemented in the CDR. This includes risk evaluation and possible solutions to a number of selected points. The smooth and practical transition between the 500 GeV CLIC and the design energy of 3 TeV is also studied.