1. CLIC Beam Physics Working Group D. Schulte 8.7.2008

2. CLIC Beam Physics Working Group Mandate The CLIC Beam Physics Working Group estimates and optimises the luminosity performance of the CLIC design and specifies the parameters of the accelerator components that are relevant for the beam. It reports to the CLIC Design and Parameters Committee. This includes to: Study and recommend beam related parameters in the frame of the parameter working group. Specify all beam related components including precision and stability Develop, document and maintain a consistent model of the machine. This includes the main beam sources, the damping rings, ring to main linac transport, main linacs, beam delivery systems and post collision line as well as the drive beam sources, combiner rings, transport lines and decelerators. In particular, to develop a coherent set of lattice decks of the whole machine. And, in collaboration with the system experts, to develop models of the performance of the relevant beam line components and to integrate specific components required by other working groups. Collect and develop a coherent set of simulations tools to study the CLIC and CTF3 beam physics. These tools will allow to include the relevant models of the system components. Develop and document the beam-based correction, tuning and feedback techniques for CLIC.

3. CLIC Beam Physics Working Group Mandate (cont.) Perform integrated studies of the expected luminosity performance of CLIC including background. Based on the luminosity target, specify emittance budgets and the beam line component parameters that are relevant for the beam. In particular to specify the beam instrumentation requirements. Perform studies of beam losses and participate in studies of the beam induced detector background. Perform and participate in beam experiments in CTF3, ATF2 and possibly elsewhere in order to analyse the measurements with beam, compare with theoretical calculations and simulations and to benchmark the simulation tools. Where appropriate participate in and contribute to the ILC beam physics activities.

4. Organisation: A Herd of Cats

6. Organisation We have a weekly meeting –To prioritise work –To take decisions –To discuss progress –To plan and organise future work –The invitation list is open Includes experts from other fields –Minutes In INDICO Webex meetings about every month –To provide link to collaboration –To inform community (e.g. ILC people) Workshops –Some activities at CLIC workshop (BDS, damping ring, simulations) –Dedicated workshop appears useful

7. Organisation (cont.) A lattice repository exists –Contains basic system description –Will add correction procedures/system descriptions Codes are on Savannah Specifications are handled by the CTC –We agree on them and ship them

8. Mailing List Erik Adli, Ilya Agapov, Ijaz Ahmed, Avni Aksoy, Fanouria Antoniou, Caterina Biskari, Hans Braun, Warner Bruns, Helmut Burkhardt, Roberto Corsini, Anne Dabrowski, Barbara Dalena, Steffen Doebert, Peder Eliasson, Konrad Elsener, Alexej Grudiev, Bernard Jeanneret, Mikael Julian Jorgensen, Jin Cheol Kim, Maxim Korostelev, Piotr Krzysztof, Andrea Latina, Thibaut Lefevre, Michel Martini, Oznur Mete, Yannis Papaphilippou, Javier Resta Lopez, Germana Riddone, Louis Rinolfi, Giovanni Rumolo, Hermann Schmickler, Daniel Schulte, Hamed Shaker, Jonathan Sladen, Lars Soby, Igor Syratchev, Frank Tecker, Rogelio Tomas Garcia, Ted Wilson, Andy Wolski, Riccardo Zennaro, Frank Zimmermann

9. Action Plan Provide input for design committee –As required Provide specifications –mainly to CTC, as required Complete design of all important beam lines –Some missing, some need improvements Define alignment, tuning and feedback –Missing for some areas, sometimes very tough Improve modelling –Models of components and imperfections –Coding –Benchmarking –Correction procedures CLIC ACE preparation –Review status and plans

10. Specifications Provide specifications to the CTC –Some specifications do exist but need to be documented in a single place –Some specifications are not yet known but can be derived in the near future –Some specifications require large amount of work and/or close collaboration with other expert groups Plan is to provide what we have until the end of the year –We started to provide specifications for the vacuum –In the near future instrumentation and magnets will follow Will respond to CTC as well as being proactive

11. Other Work Important beam lines need to be designed or revised –E.g. drive beam photo injector, drive beam accelerator, combiner rings and delay loop, first drive beam bunch compressors, drive beam bending lines into the main linac tunnel, predamping ring, damping ring, main beam RTML Alignment, tuning and feedback needs to be invented/studied for many systems –E.g. RTML, BDS, main linac, combiner rings, drive beam accelerator, beam-beam... Code, modelling and benchmarking –E.g. CTF3, ATF2, codes, interaction with experts...

12. Contact Persons ("Kümmerer") Not all the people working are listed, important input from other experts, e.g. Louis and Steffen for RTML, Roberto for drive beam, etc. Main beam areas –injectors (Louis) –damping rings (Yannis) –ring to main linac transport (RTML) (Frank S.) –main linac (Daniel) –beam delivery system (Rogelio) –machine detector interface (MDI) (Daniel) –post collision line (Konrad) Drive beam areas –drive beam injector (Steffen) –drive beam acceleration, manipulation and transport (Bernard) –drive beam decelerator (Erik) –extraction line (Bernard)

13. Contact Persons (cont.) Experimental programme –CTF3 (Roberto) –ATF2 (Rogelio) Physics modelling, code development and support –Wakefields, tracking, PLACET (Barbara) –Two-stream studies and simulations (Giovanni) –Machine background and losses, BDSIM and HTGEN (Helmut) –Intra-beam scattering (Michel) –Beam-beam effects, GUINEA-PIG (Daniel) Others –Lattice and system description repository (Rogelio) –Integrated studies and feedback (Daniel) Note: Contact persons may change