Workshop Objectives & Highlights from Daresbury Meeting Erk Jensen, CERN

Workshop Charge Compact Cavity RF Test results and performance validation (MS1) Results of successful cavity prototype tests including relevant issues and their mitigation. Develop evaluation criteria for performance in view of the LHC! Cryomodule & RF system development for SM18, SPS tests & LHC (MS2) Discuss conceptual designs maximizing the common platform with fruitful exchange of design ideas. Assess complexity of the cryomodule from design, fabrication and integration aspects. Mitigation of issues such as compatibility, CERN standards, material choices etc. Preparation for the beam tests in the SPS and future road-map (MS3) Assess the feasibility of the present construction schedule and adapt to the evolving machine schedule. This demonstration and a coherent plan is crucial for the construction of (8+2) LHC modules. 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 2

Highlights from Daresbury Meeting We could observe good progress on all fronts, but identified some critical items (Coupler feed-through for SPS CM) In order to stay consistent with the needs and without changing nominal kick (3.4 MV), we changed from 3 to 4 cavities /IP /beam /side; i.e. now total 32 cavities! The collaboration across the Atlantic works very well! Thanks to all! Our planning: Be ready with SPS CM by winter 2015/16! This is very challenging – but it should remain challenging! Maybe we were too optimistic; we will present a more realistic schedule … 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 3

Hot News: LHC schedule beyond LS1 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 4 No Linac4 connection during Run2 - only EYETS*) (19 weeks) LS2 starting in 2018 (July)18 months + 3months BC (Beam Commissioning) LS3LHC: starting in 2023 =>30 months + 3 BC injectors: in 2024 =>13 months + 3 BC Run 2Run 3 Run 4 LS 2 LS 3 LS 4LS 5Run 5 LHC schedule approved by CERN management and LHC experiments spokespersons and technical coordinators Monday 2 nd December 2013 LHC schedule approved by CERN management and LHC experiments spokespersons and technical coordinators Monday 2 nd December 2013 *) Extended Year End Technical Stop

SPS CM: Common design approach 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 5 UK 4-RodUS Double QW Conclusion – A common design approach to accommodate all the 3 cavity designs has been successfully developed. External Envelope Cryogenic Interface Cryogenic Process Alignment (external and Internal) ……. Challenges – Couplers and Tuners and their locations for the three designs are different. US RF Dipole For illustration only Shrikant Pattalwar

09-Dec-2013 Phase modulation & crabbing LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 6 CC1CC2IP Ideal crabbing Bunch phase error (late arrival) Good news: No loss of luminosity, but some offset of luminous region! But: Crab Cavities must be phase synchronized!

We clearly identified as highest priority: Get ready for SPS test on time! To get there, we will have to advance the engineering on the SPS CM! plan: Dec 9-11, 2013: LHC-CC13 – things to progress for that! Feb 6 th, 2014: CM Status update meeting March 2014: Freeze design April 2014: Advisory committee for endorsement, release Then: start procurement, cut metal 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 7

Situation with LARP 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 8

Down-selection? LARP internal review (June 2013) pushed for a “down - selection” asap, we think what they really need is to contain the cost. 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 9

The advantage of diversity Friendly competition – mutual push Complementarity Comparing methods – comparing results Consolidation of tools We learn from trying 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 10

One of these 3? No – the choices are: Can we afford to keep these 3 designs? Can we afford to discontinue one? Can we afford to keep only one? What are the choices? 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 11

What about our defined milestone? We formulated: “ Initial Compact Crab Cavity down-selection, leaving at least two CC options for technical design and prototyping ”. This was not meant to eliminate valid contenders! We have done this down-selection: 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 12

Can we make a choice in 2014? Yes: The choice is “increase our chances for success!”, i.e. continue with the 3 different, complementary designs until we can decide which cavity (cavities) can go in the LHC. We will propose criteria for this latter selection and agree on them with all involved (+ advisory committee?) We will decide what will go in the LHC after we have done relevant tests. 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 13

Tests Vertical tests Tests of dressed cavity Low power RF tests of cavity in CM RF tests of fully equipped cavity (HOM damping, power coupler) Test with beam in SPS 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 14 relevant

More highlights from Daresbury Meeting 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 15

My Daresbury conclusions We must concentrate on preparing for the SPS tests first! This requires the freeze of the CM design soon! CERN wishes to keep the 3 cavity proposals alive and supports them while they are valid. We count on LARP for continued support – may have to refine the exact scope. (for SPS, no change!) The decision which cavity can go into the LHC will have to be based on results of relevant tests – criteria to be established. Thanks to all! 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 16

Now let’s have a constructive LHC CC-13 ! 09-Dec-2013LHC-CC13, CERN EJ: Objectives&Daresbury Highlights 17