Beam Instrumentations: Requirements for Proton and Electron Beams C. Bracco, E. Gschwendtner, B. Goddard, M. Meddahi, A. Petrenko, F. Velotti Acknowledgements: WP3 and WP4 members, P. Muggli and A. Caldwell

Outlines  Introduction  Layout and optics  Electron and proton beam integration (side-injection, on-axis injection)  Electron beam line  Beam characteristics  Lattice  Wish list for diagnostics  Proton beam line  Beam characteristics  Lattice  Wish list for diagnostics  Summary

Reminder Three beams into the game! 7.16 % Phase 1 (2016): protons + laser beam  prove SMI Phase 2 (2017): protons + laser + electron beam  probe acceleration

Proton and Electron Beam  Common beam line last ~4.4 m before plasma cell C. Magnier, F. Galleazzi

Proton and Electron Beam mm 20 mm 10 m 40 mm <0.5 mm p e 10 m 40 mm p e Side injection On axis injection 20 mm 24 mm s=801m Off axis!!

Electron Beam Line Momentum [GeV/c]10-20 (nom. 15) # bunches1 p+ per bunch2.0 × 10 9 Current [nC]0.3 Norm. Emittance [mm mrad]2 e- p+ On-axis inj Quads inside the connection tunnel Final triplet * * tot. envelope: 2x Envelope Hor/Ver beam pipes Ø: mm F. m. Velotti

Electron Beam Line 1. Emittance measurement at beginning of the line  Available space (~50 cm) between elements in the connection tunnel  Vertical dispersion non-zero 2. Beam size at the plasma cell 3. BPMs for correction assuming 1vs1 strategy  14 (1 per quad) + 2 before the plasma cell  6 of them in the common part with p+ 4. Momentum measurements  Spectrometer at the end of RF gun? At one of the h- bends? 5. Bunch length measurements 6. Current measurements F. m. Velotti

Electron Beam Line 1. Emittance measurement at beginning of the line  Available space (~50 cm) between elements in the connection tunnel  Vertical dispersion non-zero 2. Beam size at the plasma cell 3. BPMs for correction assuming 1vs1 strategy  14 (1 per quad) + 2 before the plasma cell  6 of them in the common part with p+ 4. Momentum measurements  Spectrometer at the end of RF gun? At one of the h- bends? 5. Bunch length measurements 6. Current measurements MeasurementsPrecisionPosition Emittance +/- 200  m Connection tunnel Beam size +/- 50  m Before plasma cell Beam position +/- 200  m +/- 50  quads and before plasma cell Momentum+/- 7.5 keVhorizontal bends Current < 1%Before/after plasma cell F. m. Velotti

Proton Beam CNGSAWAKE Nominal Setup Momentum [GeV/c]400 # bunches p+ per bunch1.05 × × × 10 9 Repetition rate [s] Norm. Emittance [mm mrad]~ Specifications (based on LHC TL and HiRadMat requirements) for the unchanged part of the beam line (everything installed upstream of BTVG ) : BPM: 0.2 mm total accuracy Resolution: 0.1 mm (within 20 mm radius) BCT: 1->2% absolute precision BTV: Beam size precision: 0.1 mm BLM: Detect local loss of 5e8 charges Diagnostics for single bunches! ~74 times lower intensity than CNGS

Changes in the Proton Beam Line Instrumentation presently installed: BTVG BPG BLM BPG BPG BTVG BFCT BTVG BLMr /BLMl BPG BTV BPKG Target Area (not possible to reuse) Possible to reuse? (provided required modifications) ~ 90 m

What is Needed in the “New Line”? BPG

What is Needed in the “New Line”? BPG

Proton and Laser Beam Plasma cell Not real bottle neck Lase r Prot on ± 8 mm ± 6 mm ~7 mm (it must be > 5 mm!) BPG new BPG BPG new BPG

What is Needed in the “New Line”? BPG

Required Pointing Accuracy

Beam Envelope at BPMs s** [m] Tot. Env. X [mm] Tot. Env. Y [mm] Beam Pipe [mm] Accuracy [mm] BPG BPG *0.2 BPG *0.2 BPG.412xxx *0.2 BPG.412xxx BPG.412xxx /40***0.05 BPG.412xxx BPG.412xxx ** end position * 50 mm (inner diameter) vacuum chamber for new B190 dipoles, to be checked if still compatible with 60 mm aperture at BPMs (J. Hansen) *** side injection/ on axis injection Downstream of plasma cell Interlocked! Extraction from SPS must be stopped if beyond tolerances: 100  m and 15  rad

What is Needed in the “New Line”? BTV

Proton Beam Line Optics Requirements Round beam with a beam plasma cell entrance 1  = 200 ± 20  m Achieved: 1  = 202  m

Beam Envelope at BTVs S [m] Tot. Env. X [mm] Tot. Env. Y [mm] Beam Pipe [mm] Accuracy [mm] BTV BTV.412xxx /40*<0.05 BTV.412xxx <0.05 Downstream of plasma cell The last two BTVs have to be used also for the proton and laser beam setup (position: two beams coaxial)  a screen has to be added for the laser beam (reduced power during setup, see Mikhail’s talk) The Monitor downstream can be used also for the e-beam Position and beam size measurements * side injection/ on axis injection

What is Needed in the “New Line”? BLM location of vertical bottleneck (5e8 charges) BCT: 1-2% absolute precision BCT

Summary 1/2  Electron beam line:  Completely new diagnostics to measure:  Emittance  Energy  Beam plasma cell  Beam position  Bunch length  Current  Proton beam line:  Adapt existing diagnostics for AWAKE operation (1 bunch) up to BTVG (excluded) + reuse part of remaining diagnostics  Five additional BPM  Two additional monitors for beam size measurements of the p beam and position measurements for p and laser

Summary 1/2  Main challenges:  Coexistence of the e an p beams  Reduced beam pipe diameters (15-24 mm)  Almost no space around the beam pipes in common part of the lines (we’ll try to optimize the lattice):  How to implement pickups for position measurements?  How to perform beam profile measurements?  Required very high accuracy in position measurements for p and laser beam  Low electron energy and current  The option of having a unique design for on axis and side- injection is being evaluated: double diagnostics at the end of the line…..