E. GschwendtnerMDI, 18 Feb Post-Collision Line and Dumps Working Group The PCLD Working Group shall co-ordinate the design and experimental work on the post-collision line, the main dumps and the drive-beam dumps. The PCLD Working Group shall oversee the detailed work needed for the conceptual design report (CDR) of the PCLD until mid The WG is responsible for documenting the concept of the post-collision line and dumps in the CDR write-up and in form of parameter specification documents in the CLIC PBS on the EDMS repository. The main topics are: – Conceptual design of the CLIC main beam dumps, based on the ILC main beam water dumps proposal. – Conceptual design of the drive beam dumps, based on the SLAC 2.2 MW water dump. (N.B. The drive beam optics to the dumps is the responsibility of BE-ABP.) – Cost estimates of the drive beam dumps and main dumps. – Conceptual design of the post-collision line (magnets, vacuum, absorbers and intermediate dump). – Conceptual luminosity monitoring – Beam background backsplash from the post-collision collimators and dumps into the detector

E. GschwendtnerMDI, 18 Feb Work-packages and issues that will be treated in the PCLD Working Group in the technical design phase : Designs/Studies: – Optimization of the post-collision beam optics with respect to the design of the main beam dump. – Optimization of the drive beam dump. – Dump Instrumentation for luminosity monitoring and machine protection. – Radiation environment, radiation shielding, impact on environment and safety issues in the post-collision line and dump regions. – Beam pipe, beam vacuum, vacuum infrastructure and vacuum windows. – Follow-up of beam background backsplash from the post-collision collimators and dumps into the detector. – Evaluation of temperature and pressure behavior in the dumps, water circuit layout, window integrity and cooling as well as isotope production in the dumps. – Proposal for Tritium and hydrogen management in dumps. – Window, water circuit and dump tank maintenance, remote handling, automated window replacement. – Integration of the dumps (link to CLIC Civil Engineering and Services (CES) Working Group). Experimental/Construction work: – Engineering Design for a 10 MW dump ready for use with beam, when under the name of “CLIC0” a full drive beam accelerator demonstrator is planned to be built at CERN in the period

E. GschwendtnerMDI, 18 Feb Meetings – The PCLD Working Group meets about every 6 weeks. Reporting – The PCLD Working Group reports to the CLIC Technical Committee (CTC). For certain topics the Working Group shall propose speakers for CLIC Friday meetings, the Machine and Detector Interface (MDI) meetings or the Linear Collider Detector (LCD) meetings. – The PCLD Working Group shall report to the CLIC Cost and Schedule Working Group on request. Milestones – The PCLD Working Group must have submitted the Conceptual Design Report (CDR) of the Post- Collision Line and Dumps until mid The Composition of the Post-Collision Line and Dumps Working Group – Appleby Robert (Cockcroft Institute), Apyan Armen (EN-MEF), Deacon Lawrence (EN-MEF), Gatignon Lau (EN-MEF), Gschwendtner Edda (EN-MEF), Jeanneret Bernard (BE-ABP), Lefevre Thibaut (BE-BI), Losito Roberto (EN-STI), Maglioni Cesare (EN-STI), Modena Michele (TE-MSC), Salt Mike (Cockcroft Institute), Tomas Garcia Rogelio (BE-ABP), Veness Raymond (TE-VSC), Uythoven Jan (TE-ABT), Vlachoudis Vasilis (EN-STI), Vollaire Joachim (DGS-RP). – Possible collaborations with e.g. ILC, Indian or Polish institutes. – Chairperson: Gschwendtner Edda