Welcome to the 3 rd LOW  RING workshop in Oxford 8-10 July 2013

Workshop series The workshop series was initiated by the joint ILC/CLIC damping ring working group and puts together three communities damping rings lepton colliders light sources to discuss common issues in the design, realisation and operation of low emittance rings 1 st workshop, CERN, Geneva, January 2010(~70 delegates) 2 nd workshop, Heraklion, Crete, September 2011(~60 delegates) Oxford, UK this round(~80 delegates)

3 rd Lowering workshop - Oxford

Low emittance rings community

Workshop charge Charge and objectives Share info about current programmes on low emittance rings Share info about main issues/problems in Accelerator Physics, Collective effects, LER technology Discuss and get feedback on proposed solutions Identify and prioritise R&D Identify and fostering collaborations Written report to be edited in the weeks after the workshop by the SPC coordinators

Accelerator Physics questions (…selected) What are the guidelines for ultra low emittance ring design that define the main ring parameters? (emittance, energy, current, lattice type, …) What quality factors that define a good lattice design? (ratio straights circumference, emit. vs circumference, …) What are the approaches/tools to optimise linear dynamics and reduce the emittance? Is there an optimal M in MBA lattices? What is the optimal length of the straight section? How can DA and momentum aperture be maximised? What DA and lifetime are acceptable for operation? Are beam-based optimisation tools developed in existing machine sufficient for ultra-low emittance ring tuning? … What R&D and collaborations can be fostered?

Collective effects questions (..selected) What are the limits on the stored current in ultra-low emittance lattice? What are the main collective effects? Is IBS the limiting factor? What are the implications of operating with short bunches? Are harmonic cavities and effective solution for ultralow emittance rings? Under what conditions RF heating is a problem? What are the guidelines for the design of a low impedance machine? (interplay with vacuum and coating technology) Are the estimates (analytical and numerical) of the impedance budget in agreement with measurements? What are the main tracking codes for collective effects ? Do they need further developments? Do they agree with measurements? … What R&D and collaborations can be fostered?

Technology questions (…selected) What are the apertures and the gradients required in ultra low emittance rings? A fundamentally new design emerging? Are tolerances on the magnet design and alignment realistic? What are the latest development in SC wigglers? What are the vacuum challenges of working with small diameters chambers (outer diameters mm)? Is NEG technology the solution for vacuum control? What are the implication on the engineering of the ring? Are beam diagnostics for orbit, beam size and emittance measurement sufficiently precise for ultra low emittance beam? Can they drive effective feedback systems? Is kicker magnet technology sufficient for application to ultra low emittance ring? … What R&D and collaborations can be fostered?

Workshop organisation 5 main session reflecting the workshop charges AP1 design/modellingMonday morning Collective effectsMonday afternoon Technology 1 (magnets vacuum)Tuesday morning AP2 experimentsTuesday afternoon Technology 2 (diagnostics and kickers)Wednesday morning 30 minutes discussion after each session 1h “report writing” at the end of each day Parallel sessions Denis Sciama (DS) Lecture theatre and Fisher Room (FR) Monday afternoon AP in DS – collective effect in FR Tuesday afternoon AP in DS – technology in FR Wednesday afternoon technology DS

Workshop organisation 5 main session reflecting the workshop charges AP1 modelling:L. Nadolski, L.Emery, A. Streun Collective effectsR. Nagaoka, B. Podobedov Technology 1 (magnets vacuum)D. Einfeld, J. Kay AP2 experimentsJ. Safranek, M.Biagini, P. Raimondi Technology 2 (diagnostics and kickers)J. Urakawa, P. Kuske, B. Hettel Wednesday afternoon summaries Students’ Posters in Fisher room Prize Winner announced at the Balliol Dinner on Tuesday evening (7.30pm)

Eucard year project co funded by the EU and partners institutions 6 networking activities and 4 joint research activities WP6: low emittance ring Network to “federate for the first time these communities towards a common effort in defining theoretical and technological solutions and in promoting common technical choices.” See Yannis’s talk on Wednesday afternoon Four main workshops in the next 4 years – ours is the first Several topical workshops: Workshop on Collective Effects (SOLEIL) January 2014 : See R. Nagaoka’s on Monday afternoon

Safety The assembly point is outside the Denys Wilkinson Building Fire alarm test scheduled every Monday at 10am