1. Muon Accelerators for Particle Physics Working Group Summary Conveners: Jaroslaw Pasternak Imperial College/RAL STFC Mark Palmer Fermilab Proton Accelerators for Science and Innovation Workshop January 12-14, 2012 Fermilab

2. Working Group Goals Review the current status of the various projects and ongoing programs Present future directions and new ideas Underline the synergies between the UK and the US programs Discuss the synergies and a strategy to strengthen the collaborative efforts  Target areas where enhanced collaboration can enable significant strides forward Proton Accelerators for Science and Innovation 2

3. Parallel Session Agenda – Day 1 Introduction Early Stage Efforts – Mu2e and g-2 at FNAL – E. Prebys – COMET – Y. Uchida Mid-term Future Efforts – VLENF – A. Bross – PRISM – J. Pasternak – Next Generation Mu2e and g-2 at FNAL – V. Lebedev Long-term Future Efforts – IDS-NF – N. Bliss – Muon Collider Options – S. Geer Key R&D Demonstrations – MICE 4D Cooling Program – P. Soler – EMMA FFAG Demonstration – J. Pasternak – 6D Cooling Options – R. Palmer Discussion Proton Accelerators for Science and Innovation 3

4. Parallel Session Agenda – Day 2 Review of Potential Synergies in the UK-US Programmes – UK Perspective – A. Seryi – US Perspective – M. Zisman Discussion Documentation Proton Accelerators for Science and Innovation 4

5. Mu2e Experimental Goal, E. Prebys Proton Accelerators for Science and Innovation Workshop, Jan. 2012 5 Aluminum Nucleus Nucleus Captured Captured  -  - N  e - N E e  105 MeV  - - - - e-e-e-e- Monoenergetic electron Stop muons in an aluminum target Goal: measure with a 90% CL of <10 -16

6. g-2 Experimental Technique, E. Prebys Capture polarized 3.094 GeV/c muons in a uniform magnetic field – Use electric quadrupoles to focus. “Magic” momentum cancels component of precession caused by E field – Remaining precession directly proportional to a  Experimental apparatus will be moved from Brookhaven Proton Accelerators for Science and Innovation Workshop, Jan. 2012 6 Momentum Spin e

7. Y. Uchida COMET is going ahead with Phase I data-taking by 2017

8. The PRISM/PRIME is a next generation cLFV experiment based on FFAG ring, which allows to: - reduce the muon beam energy spread by phase rotation, - purify the muon beam in the storage ring. PRISM - Phase Rotated Intense Slow Muon beam Single event sensitivity – 3×10 -19 Expected upgrade path for COMET J. Pasternak

10. V. Lebedev

11. Very Low Energy Neutrino Factory, A. Bross

12. Muon Decay Ring RLA II 3.6 – 12.6 GeV Pre Linac 244 – 900 MeV FFAG 12.6 – 25 GeV RLA I 0.9 – 3.6 GeV Cooler Rotator Buncher Target Protons Muons Neutrino Beam Muon Decay Ring Target to Muon Decay Rings 3000 - 5000 km to Detector 7000 - 8000 km to Detector Tilt angle 36  Tilt angle 18  N. Bliss Neutrino Factort

13. EMMA, JP EMMA - demonstration of a linear non-scaling Fixed Field Alternating Gradient accelerator : Performed acceleration in serpentine channel (outside rf bucket) in around 10 turns. Achieved operation with large tune variation due to natural chromaticity during acceleration. Proves that a linear non-scaling FFAG works!

14. P. Soler

15. MUON COLLIDER SCHEMATIC, S. Geer 15 Proton source: Example: upgraded PROJECT X (4 MW, 2±1 ns long bunches) 10 21 muons per year that fit within the acceptance of an accelerator:   N =6000  m  //N =25 mm √s = 3 TeV Circumference = 4.5km L = 3×10 34 cm -2 s -1  /bunch = 2x10 12  (p)/p = 0.1%   N = 25  m,  //N =70 mm  * = 5mm Rep Rate = 12Hz

16. 16 MAP PRIORITIES & DELIVERABLES, S. Geer Deliver on commitments to making MICE and the IDS-NF studies a success. Focus on key technology development and testing RF cavities in magnetic fields High-field solenoids for final cooling Rapid cycling magnets for RCS (small seed effort) Deliver a Design Feasibility Study to enable the community to judge the feasibility of a multi-TeV Muon Collider (~FY16): Hardware R&D and experimental tests to guide & validate the design work. A simulation of a MC complex based on technologies in-hand or that can be developed with a specified R&D program. Rough cost range. R&D plan for longer term activities (e.g. 6D cooling expt) Coordinate with the physics community on physics capabilities, detector and MDI

17. R. Palmer

18. Muon beam diagnostics (applies to all projects) Joint collaborative plan for 6D and final cooling channel component R&D (develop over next year) Mu2e/g-2/COMET/PRISM - Curved solenoid development for Mu2e/COMET/PRISM and g-2 - Kicker design overlap between g-2 and FFAG efforts - SC inflector for g-2 and SC septum for FFAG? - Design and simulations of pion/muon production, transport, collection and backgrounds issues. VLENF - Physics case + accelerator technology testbed case. - Detector background study (MIND’ analysis) – for 6-week study for input to Fermilab Task Force on Short Baseline Neutrino Physics. - Programmatic interface options – Can it co-exist with other projects - Simulations – target to neutrino flux, detector - Lattice development for ring, injection with PRISM/IDS List of topics for collaboration in strategic near and middle term areas:

19. IDS-NF - Ongoing collaboration to finish RDR: -Staging scenarios, -Technology R&D (planning). - Explore post-RDR plans (to be explored between now and next meeting) Muon Collider - Explore options for detector discussion at next meeting - Explore common interests on full range of R&D items – identify items to target at next meeting List of topics for collaboration in strategic long term areas:

20. MICE and MuCool - Explore long term plan for MICE facility (IDS channel, technology test, 6D options, etc) - Cavity test options and R&D for RF in high magnetic field EMMA - Review whether the necessary knowledge has been obtained from performed experiments - Look at motivations for an extended experimental program – review what is actually required 6D Cooling - Design and simulation of 6D and final cooling - Review of final stage options List of topics for collaboration in R&D areas:

21. Report on long term plan for MICE facility. Review results and plans for EMMA and evaluate if an extension is needed. Report on physics case and facility design for the VLENF. Plan for collaborative effort on muon beam diagnostics. Report on post-RDR possibilities for NF. Report on directions for R&D on Muon Collider including 6D cooling/test facility options. Detector activity for MC – explore the possibilities for collaboration. Prepare a coherent plan for the 5 year time period. List of deliverables to be achieved by the next meeting:

22. We would like to thank all participants for fruitful contributions to the working group, the organisers of the workshop for a warm atmosphere (despite of cold weather) and UK: Foreign and Common Wealth Office Science and Innovation Network UK: Science and Technology Facilities Council US: Department of Energy, Office of High Energy Physics – US: Fermi National Accelerator Laboratory for financial support. Thank You very much!