The FAIR Antiproton Target B. Franzke, V. Gostishchev, K. Knie, U. Kopf, P. Sievers, M. Steck Production Target Magnetic Horn (Collector Lens) CR and RESR Radiation Protection

Creation of antiprotons (p or pbar) p, > 1 GeV m = E / c² m p = m pbar  1 GeV / c² p p pbar p p, > 6 GeV p at rest m = E / c² p p p pbar_

Creation of antiprotons (p or pbar) _ p = 3.82 GeV / c, E = 3 GeV, Bρ = 13 Tm

FAIR / CERN / FNAL pbar Sources CERN (AC+AA)FNAL E(p), E(pbar)25 GeV, 2.7 GeV120 GeV, 8 GeV acceptance 200  mm mrad  30  mm mrad protons / pulse1 - 2 × ≥ 5 × pulse length5 bunches in 400 nssingle bunch 1.6 µs cycle time4.8 s1.5 s

FAIR / CERN / FNAL pbar Sources cycle time 10 s (cooling time in the CR) overall pbar yield: 5 × pbar/p (based on CERN data) → 1 × 10 7 pbar/s Increases the pbar yield by  50 % FAIR Collector ring will be operated at h = 1, CERN ring was operated at h = 6 Time needed for stochastic cooling in CR (AC), upgrade possible FAIRCERN (AC+AA)FNAL E(p), E(pbar)29 GeV, 3 GeV25 GeV, 2.7 GeV120 GeV, 8 GeV acceptance 240  mm mrad200  mm mrad  30  mm mrad protons / pulse≥ 2 × × ≥ 5 × pulse lengthsingle bunch (50 ns)5 bunches in 400 nssingle bunch 1.6 µs cycle time10 s4.8 s1.5 s

pbar Distribution After the Target R.P. Duperray et al., Phys. Rev. D 68, (2003) p pbar = 3.82 GeV/c ± 3% From ~ 2.5 × pbar / (p cm target) ~ 5 × (or 2 %) are "collectable" z / cm y / cm E p = 29 GeV

MARS Simulation of the pbar Yields

reaction products B  1/r primary beam does not hit the horn Collecting pbars: Magnetic Horn

CERN ACOL Horn, I = 400 kA Collecting pbars: Magnetic Horn target beam axis magnetic field area

Collecting pbars: Magnetic Horn

MARS Simulation of the pbar Yields yield = pbars in the ellipse primary protons

MARS Simulation of the pbar Yields

Temperature Increase in the Target c Ir = 130 J kg -1 K -1 c Cu = 385 J kg -1 K -1 c Ni = 440 J kg-1 K -1

RESR and CR Rings CR circumference: 212 m acceptance: 240 mm mrad bending power: 13 Tm stochastic cooling RESR circumference: 240 m acceptance: 40/30 mm mrad bending power: 13 Tm stochastic cooling

CR: Bunch Rotation and Stochastic Pre-Cooling E t bunch rotation adiabatic debunching stochastic cooling  E/E = ± 3 % ± 0.75 % ± 0.5 % ± 0.1 % 50 ns

stack corestack tail Cross section throught the vacuum chamber at the momentum pick-up stochastic cooling for stack core RESR: Antiproton Accumulation

stack corestack tail 160 mm (  p/p = 0.8 %) stochastic cooling for stack core partial aperture injection kicker injected beam from CR acceleration by HF (not in resonance with stack) Antiproton Accumulation

stack corestack tail 160 mm (  p/p = 0.8 %) stochastic cooling for stack core stochastic cooling for beam deposit (high amplification) Antiproton Accumulation

stack corestack tail 160 mm (  p/p = 0.8 %) stochastic cooling for stack core Antiproton Accumulation

stack core 160 mm (  p/p = 0.8 %) deceleration by HF Antiproton Accumulation

stack core 160 mm (  p/p = 0.8 %) extraction kicker Antiproton Accumulation

FAIR / CERN / FNAL pbar Sources cycle time 10 s (cooling time in the CR) overall pbar yield: 5 × pbar/p (based on CERN data) → 1 × 10 7 pbar/s Increases the pbar yield by  50 % FAIR Collector ring will be operated at h = 1, CERN ring was operated at h = 6 Time needed for stochastic cooling in CR (AC), upgrade possible FAIRCERN (AC+AA)FNAL E(p), E(pbar)29 GeV, 3 GeV25 GeV, 2.7 GeV120 GeV, 8 GeV acceptance 240  mm mrad200  mm mrad  30  mm mrad protons / pulse≥ 2 × × ≥ 5 × pulse lengthsingle bunch (50 ns)5 bunches in 400 nssingle bunch 1.6 µs cycle time10 s4.8 s1.5 s cycle time 10 s (cooling time in the CR) overall pbar yield: 1 × pbar/p (based on CERN data) → 2 × 10 7 pbar/s

Target Station

Target Exchange (target on air!)

Target Station

Dose rates around the pbar target 170 m

Fluka input, top view airconcreteirongraphitevacuum Super NESR FRS SIS18 CR RESR atomic physics target from SIS 100

Equivalent dose rates during operation Equivalent Dose rate [Sv/h], 2 × protons per pulse, 0.1 Hz

Induced Activity after Shut-Down airplane at m

Induced Activity after Shut-Down vertical section 4 m downstream of target air concrete iron

Summary Yield (target / horn / separator): 11 cm Ni-target, copy of CERN horn ~ 2 × pbar per primary proton (4 × 10 7 pbar / s) Yield (out of RESR): ~ 1 × pbar per primary proton (2 × 10 7 pbar / s) No significant increase of this number can be expected with another type of collector like a Li-lens. time averaged, less than 1 kW is deposited in the target higher repetition rate should be no problem Radiation protection: no principal problems up to now