AWAKE electron source New Electron Source WP at CERN Base Line Scenario Simulations Diagnostics Questions and Issues Conclusions AWAKE workshop, CERN, April 9th-11th, 2014

Layout of AWAKE Experiment CI SAC meeting 2013 Layout of AWAKE Experiment

Layout of Electron source CI SAC meeting 2013 Layout of Electron source To be developed in the future

Base line scenario Base line Use PHIN gun and equipment (convert to copper cathode ?) Klystron and Modulator from CTF3 Get booster from Cockcroft/Lancaster collaboration (specs from CERN) ? Additional equipment needed (solenoids, vacuum, wave guides, girders) Diagnostics, PHIN, CERN, INFN (to be defined) Beam dynamics simulations, CERN ,Cockcroft ? Integrated test in CTF2 in 2016, external help welcome Installation and commissioning into CNGS area in 2017, external help welcome Alternative, upgrade Look for alternative gun, Califes, Cockcroft/Lancaster, INFN ? (goal will be ultimate beam performance, tiny emittance, ultra short bunches) Evaluate performance, impact and cost

Work package responsibilities Tasks Responsible RF power CERN, Gerry McMonagle GUN CERN, Steffen, Eric Chevallay Booster STFC, Graham Burt ? Laser CERN, Valentin Fedosseev Instrumentation CERN, Lars Jensen Mechanical design CERN, Nicolas Chritin Magnets CERN, Jeremie Bauche Vacuum CERN, Jan Hansen Controls CERN, Marine Gourber-Pace Integration CERN, Fred, Ans Pardons Commissioning CERN, Steffen, Chiara Simulations CERN,STFC, Steffen, Oznur Mete ? Interlocks, Safety CERN, Rui Nunes Be aware this list is certainly incomplete and preliminary

AWAKE – INJECTOR MODULE Quadrupole Magnet Horizontal and Vertical Corrector Magnet YAG Slit YAG Booster Linac 1m long RF Gun Beam Direction Synthetic Granite Girder Ion Pump ? Support Pedestal Ion Pump Proposal by STFC Daresbury

AWAKE electron source schematic Klystron Incident, Reflected Power and phase A,f Spectrometer Laser +Diagnostics Incident, Reflected, transmitted Power E, DE MTV Matching triplet FCT Emittance MS FC BPR BPR BPR RF GUN VPI MTV, Emittance Corrector Accelerator Length ~ 4 m

Awake electron beam requirements Parameter Phase 1 Phase 2 Beam Energy 13-16 MeV 20 MeV Energy spread (rms) 0.1 % Bunch Length ~ 4 ps < 1 ps Laser/Rf synchronization 1 ps 0.1 ps Free Repetition Rate 10 Hz Synchronized repetition rate 0.03 Hz Beam Focus Size < 250 mm Divergence < 3 mrad Normalized Emittance 2-5 mm mmrad 0.5 mm mrad Bunch Charge 0.2 nC 1 nC

Phin gun, 20 MV/m structure, 0.1 nC, 1 mm 3 ps laser Awake simulations Phin gun, 20 MV/m structure, 0.1 nC, 1 mm 3 ps laser

Phin gun, 20 MV/m structure, 0.2 nC, 1 mm laser Awake simulations Phin gun, 20 MV/m structure, 0.2 nC, 1 mm laser

Phin gun, 20 MV/m structure, 0.2 nC, 1 mm laser, Awake simulations Phin gun, 20 MV/m structure, 0.2 nC, 1 mm laser, 1 ps laser

Phin gun, 20 MV/m structure, 0.1 nC, 0.5 mm laser Awake simulations Phin gun, 20 MV/m structure, 0.1 nC, 0.5 mm laser

Awake simulations Phin gun, 20 MV/m structure, 0.1 nC, 0.25 mm laser Many variants are possible Clear laser and beam parameter specification are needed for the simulations Should define reference scenarios for the simulations

Booster structure Some rough numbers 1 m long constant gradient structure f= 2998.55 MHz Q ~ 15000 r/Q ~ 70 MW DV= 15 MV Tf= 280 ns, 2a ~ 2 cm Po = 11 MW PHIN gun needs about 10 MW for 85 MV/m Roughly 30 MW needed to power the injector (one klystron)

Define rough commissioning scenario, what do we measure where and how Beam instrumentation Instrument How many Resolution Precision BPMs 3 50 mm ? ? Phase monitor 1 ps ? Screen 20 mm ? Multi slit < mm mrad ? FCT pC ? Faraday Cup Spectrometer 10 keV ? Streak Camera < ps ? Laser diagnostics: laser power, position, virtual cathode, micro pulse length RF diagnostics: rf power signals, rf phase Define rough commissioning scenario, what do we measure where and how

Klystron Issues Transport: Study of transport and possibility to exchange klystron in situ has to be done, likely a local lifting device is needed Synchronisation: 3 GHz synchronized signal is needed as well as a number of timing triggers Safety: The modulator contains Oil together with high voltage, the waveguide may contain SF6 A risk assessment has to be done to determine fire protection measures !! Remote control: We usually have access to those klystron while running beam, likely need to improve the remote control capabilities

Questions A few question to trigger discussions: Timing: How is it organised, beam, controls, data acquisition Controls: Guidelines for the control system, hardware, FESA, data base Experiment data taking: which information we need synchronized, sampling rate (BPM’s protons, electrons, Laser, spectrometer )? Location of electronics for power supplies, diagnostics and data acquisition

Rough time line 2014 2015 2016 2017 Beam line design Booster design Infrastructure definition Rough Integration Detailed Component design and fabrication Detailed integration Infrastructure installation (Water, Power, Ethernet, klystron handling) Installation and commissioning In CTF2 (may be not all hardware) Infrastructure installation, electron source shielding, access system, racks Installation of source and commissioning in AWAKE Infrastructure and issues before installation: Water, power, Ethernet, klystron handling equipment, racks for electronics, electron source shielding, access system, laser beam line, alignment concept, commissioning concept, controls

Conclusions New CERN work package for the electron source in place Many open questions we have to address in the future Beam requirements for first phase likely possible with PHIN gun and booster Some useful equipment should be available from CTF3 Need detailed beam and laser specifications Requirements for second phase challenging to fulfil simultaneously A lot of work ahead, help is very welcome

End

Awake electron beam work package reflections Questions: Access scenario, where can we go during experiment Location of power supplies, electronics, data acquisition, vacuum equipment Location of klystron/modulator elements Transport of klystron/modulator items, crane for mounting klystron ? Safety requirements, restrictions Electron source housing, how does it look like Beam diagnostics, what has been done for the beam line yet, BPMs, correctors Control system, beam, vacuum Water, electricity availability Clarify collaborations, with UK, Frascati ? Define time constraints, milestones

Single plasma cell @side injection

2 plasma cells/on-axis injection

Phin gun, 20 MV/m structure, 0.01 nC, 0.5 mm laser Awake simulations Phin gun, 20 MV/m structure, 0.01 nC, 0.5 mm laser