Introduction to Accelerators Part 3 M W Poole

Introduction to Accelerators Part 3 M W Poole Past Director and Honorary Scientist ASTe. C Cockcroft Education Lectures M W Poole

The story so far. . . • • • Principles of accelerators and early history Types – illustrated Beam dynamics in synchrotrons DL origins - NINA Synchrotron radiation Storage rings - Daresbury SRS Accelerator science and technology Application to Particle Physics - LEP and LHC Superconducting technology - magnets and RF New energy frontier proposals - ILC and CLIC UK collider R&D activities Cockcroft Education Lectures M W Poole

High Power Proton Systems • Wide range of applications • Push for intensity rather than energy • High beam current issues - supply and control (losses) • No radiation emission effects • Major space charge concerns Cockcroft Education Lectures M W Poole

ISIS Spallation Neutron Source At RAL site – operational since 1983, replacing NIMROD 800 Me. V protons, 200 µA, 160 k. W on tungsten target ~2× 1016 neutrons/second (mean) from spallation H– ion source (35 ke. V) 665 k. V H– RFQ 70 Me. V H– linac 800 Me. V proton synchrotron Cockcroft Education Lectures M W Poole

Penning Ion Source (H-) • Hydrogen gas - plasma • ~50 A arc current • Caesium to lower cathode work function 35 ke. V ISIS = 35 m. A Upgrade to 65 m. A 600°C Anode Cathode 200°C 10 mm John Thomason Cockcroft Education Lectures Complex em/thermal modelling M W Poole

Ion Source Note ion extraction slit Cockcroft Education Lectures Extraction electrode added M W Poole

RFQ Injector Upgrade (2004) 665 ke. V Radio Frequency Quadrupole Cockcroft-Walton Set Cockcroft Education Lectures M W Poole

Linac Views 70 Me. V Cockcroft Education Lectures M W Poole

Views inside ISIS Ring Cockcroft Education Lectures M W Poole

High Power Spallation Target Reflector Primary target Protons Moderators Three moderators: Liquid hydrogen (20°K) Methane (100°K) Water (43°C) Cockcroft Education Lectures M W Poole

Second Target Station 10 pps (every fifth pulse) 200 k. W ÷ 5 = 40 k. W Commissioning recently completed Cockcroft Education Lectures M W Poole

Target Station 2 Cockcroft Education Lectures M W Poole

View of ISIS on RAL Site TS-2 TS-1 Cockcroft Education Lectures M W Poole

Previous ISIS Upgrade Paths 2 nd harmonic RF added C-W Set replaced by RFQ New ~180 Me. V linac ? Present 70 Me. V linac Cockcroft Education Lectures Generic solution ? M W Poole

Latest ISIS MW Upgrade Concept ISIS (0. 8 Ge. V) Diamond 3 Ge. V synchrotron 0. 8 Ge. V linac Cockcroft Education Lectures M W Poole

PSI - World’s Most Powerful Accelerator Zurich 590 Me. V 2 m. A 1. 2 MW Sector Focusing Cyclotron Cockcroft Education Lectures M W Poole

SNS Project - Oak Ridge, USA • 1 MW Next Generation Neutron Source • 1 Ge. V H- driver - superconducting above 185 Me. V (first in world, 805 MHz) • Charge exchange injection to accumulator/compressor ring (700 ns pulses) • Liquid mercury target (18 tonnes, 1 m 3) Linac = 350 m Ring = 250 m Cockcroft Education Lectures M W Poole

SNS Linac Systems Drift Tube Linac - DTL (400 and 800 MHz) Coupled Cavity Linac - CCL Superconducting main linac Cockcroft Education Lectures M W Poole

Variable SC Cavity Gradients Cockcroft Education Lectures M W Poole

Japanese Multi-Use Facility (J-PARC) 1 MW Cockcroft Education Lectures M W Poole

View of J-PARC Serious earthquake damage Cockcroft Education Lectures M W Poole

J-PARC: RFQ, linac, synchrotron (injection) and target Cockcroft Education Lectures M W Poole

ESS-S Scandinavia, Lund — 5 MW, long pulse 17 Partners Pre-construction: 2009 -2013 Operations: 2019 ? Cost ~ 1. 5 Geuro UK role still unclear Cockcroft Education Lectures M W Poole

Proposed European Spallation Source ESS accelerator front-end stimulated RAL proton driver work 5 MW H ion source (65 m. A) RFQ Beam chopper (2. 5 Me. V) 2. 5 Ge. V Linac Solution 50 m. A, 4 % duty cycle Cockcroft Education Lectures Drift tube linac (20 Me. V) (no ring) M W Poole

Neutrino Factory Concept High current H– source Proton Target Driver Capture ‘far’ detector (5000– 8000 km) Cooling Muon Storage Ring Muon Acceleration ‘local’ detector ‘near’ detector (1000– 3000 km) Cockcroft Education Lectures M W Poole

Neutrino Factory Design Studies • Collaboration of 6 HEIs with ASTe. C • Glasgow IC Liverpool Oxford Sheffield Warwick • Funding also boosted in 2004 – and sustained • Sponsored International Scoping Study and now IDS • Proton drivers and muon accelerators (eg FFAG) • Technology programme Front End Test Stand • Targets RF breakdown studies MICE FP 7 Euro. Nu Design Studies Cockcroft Education Lectures M W Poole

Neutrino Factory Early Outline Reduction of muon phase space FFAG substitute ? Cockcroft Education Lectures M W Poole

Present Baseline Design Cockcroft Education Lectures M W Poole

Proton Driver Example Cockcroft Education Lectures M W Poole

Muon Acceleration Solution ? Cockcroft Education Lectures M W Poole

Muon Storage Cockcroft Education Lectures M W Poole

NF Accelerator Challenges • 5 -10 MW proton beam generation • Pion target survival • Muon capture (and cooling ? ) • Muon acceleration and storage Conceptual studies have UK funding (to 2012) EU FP 7 Design Study (2007 -2010) Cockcroft Education Lectures M W Poole

MICE – Cooling Experiment at RAL Muon Ionisation Cooling Experiment ISIS source Cockcroft Education Lectures M W Poole

MICE Layout on ISIS Cockcroft Education Lectures M W Poole

An Old Accelerator Rediscovered Fixed Field Alternating Gradient Chandrasekhar Bohr 20 to 400 ke. V Operated at MURA in 1956 Variant of cyclotron No field ramp Cockcroft Education Lectures M W Poole

Fixed Field Alternating Gradient (FFAG) Developed in Japan - Scaling Type Magnets are large, complex & expensive Orbit excursion ~0. 9 m + where k=7. 5 Bz(r) Scaling r Cockcroft Education Lectures Bz(r) Non-scaling r M W Poole

Demonstration of Scaling Device at KEK 50 -500 ke. V 1 k. Hz June 2000 POP Cockcroft Education Lectures M W Poole

Non-scaling Solution Advantage • Much smaller orbit excursion • Linear fields possible Cheaper magnets Asynchronous acceleration Huge momentum compaction Resonance crossing Cockcroft Education Lectures M W Poole

BASROC/CONFORM ‘Basic Accelerator Science and Radiation Oncology Consortium’ • First ever non-scaling FFAG demonstration • EMMA - construction of small electron Po. P experiment • PAMELA - prototype proton device for medical development (design only) • Issues: resonance crossing and asynchronous acceleration • Full design of EMMA completed (international input) • Construction completed early 2010 • Use of ALICE as injector • Accelerator physics studies under way COnstruction of a Non-scaling FFAG for Oncology, Research and Medicine Cockcroft Education Lectures M W Poole

EMMA at Daresbury Novel form of FFAG – project funded from March 2007 20 Me. V demonstrator £ 5. 6 M (£ 3. 8 M capital £ 1. 8 M staff) Initial grant duration 3. 5 years Cockcroft Education Lectures M W Poole

Compact EMMA Cell structure Low Energy Beam High Energy Beam Circumference = 16. 6 m Cells (42) = 394 mm no dipoles Quads = 59 and 76 mm Aperture = 40 -50 mm D Quadrupole x 42 F Quadrupole x 42 BPM x 82 16 Vertical correctors 19 cavities (180 k. V) Straights = 210 mm Cockcroft Education Lectures M W Poole

Beam Dynamics Challenges Tune plane EMMA will investigate ! Cockcroft Education Lectures M W Poole

Beam Commissioning Cavity FQUAD DQUAD Full ring circulation achieved Aug 2010 Injection at 10 -20 Me. V First Turn Second Turn Cockcroft Education Lectures 1000 turns No RF First Turn Ion Second. Turn Pump M W Poole

Front End Test Stand at RAL (FETS) FETS planned main components: • High brightness H- ion source. • Magnetic Low Energy Beam Transport (LEBT). • High current, high duty factor Radio Frequency Quadrupole. • Very high speed beam chopper. • Comprehensive diagnostics. Demonstration of injector for multi-MW source Cockcroft Education Lectures M W Poole

Front End Test Stand Plan high speed beam chopper & MEBT Ø 324 MHz, 3 Me. V RFQ Ø 3 solenoid magnetic LEBT ØH ion source - 60 m. A, 65 ke. V 2 ms pulse length 50 pps RFQ Model - IC 4 vane Cockcroft Education Lectures M W Poole

Accelerator Driven Systems (ADS) • Protons and ions (mainly) • Transmutation • Sub-critical Reactors (Thorium) – 10 -20 MW requirements – extraordinary reliabilities – compactness Need for major R&D programmes Cockcroft Education Lectures M W Poole

New Applications Sub-critical Thorium Reactor Proton & Carbon Therapy Dedicated Muon Source Cockcroft Education Lectures M W Poole

THOREA Collaboration • Alternative fission reactors – proton accelerator driver • Use Thorium (abundant, widespread) • Spallation Neutrons: 232 Th 233 Pa 233 U fission • Accelerator consumes 5 -10% of power • Does not generate Actinides • Consumes Actinides and nastiest fission products from conventional reactors • Very proliferation resistant Cockcroft Education Lectures M W Poole

Reliability Challenge D Findlay Cockcroft Education Lectures Daily trip rate > trip length M W Poole

PAMELA – an Oncology FFAG Solution ? 240 Me. V p 450 Me. V C UK design study underway Cockcroft Education Lectures M W Poole

Fusion Route Alternative - IFMIF International Fusion Materials Irradiation Facility Deuteron beam 40 Me. V 250 m. A Liquid Li 20 dpa/year neutrons • Parallel development to ITER - feeds DEMO • Location ? Cockcroft Education Lectures 10 MW ! M W Poole