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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. p. p. p, > 1 GeV. p. pbar. m = E / c²
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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 p p p, > 1 GeV p pbar m = E / c² mp = mpbar 1 GeV / c² p p p at rest p, > 6 GeV pbar p m = E / c²
_ Creation of antiprotons (p or pbar) p = 3.82 GeV / c, E = 3 GeV, Bρ = 13 Tm
FAIR / CERN / FNAL pbar Sources Increases the pbar yield by 50 % cycle time 10 s (cooling time in the CR)overallpbar yield: 5 × 10-6 pbar/p (based on CERN data) → 1 × 107 pbar/s 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
pbar Distribution After the Target Ep = 29 GeV y / cm z / cm ppbar = 3.82 GeV/c ± 3% From ~ 2.5 × 10-4 pbar / (p cm target) ~ 5 × 10-6 (or 2 %) are "collectable" R.P. Duperray et al., Phys. Rev. D 68, 094017 (2003)
Collecting pbars: Magnetic Horn B 1/r primary beam does not hit the horn reaction products
Collecting pbars: Magnetic Horn target beam axis magnetic field area CERN ACOL Horn, I = 400 kA
MARS Simulation of the pbar Yields pbars in the ellipse yield = primary protons
Temperature Increase in the Target cIr = 130 J kg-1 K-1 cCu = 385 J kg-1 K-1 cNi = 440 J kg-1 K-1
CR: Bunch Rotation and Stochastic Pre-Cooling bunch rotation adiabatic debunching stochastic cooling DE/E = ± 3 % ± 0.75 % ± 0.5 % ± 0.1 % 50 ns E t
RESR: Antiproton Accumulation Cross section throught the vacuum chamber at the momentum pick-up stochastic cooling for stack core stack core stack tail
Antiproton Accumulation partial aperture injection kicker stochastic cooling for stack core acceleration by HF (not in resonance with stack) stack core stack tail injected beam from CR 160 mm (p/p = 0.8 %)
Antiproton Accumulation stochastic cooling for beam deposit (high amplification) stochastic cooling for stack core stack core stack tail 160 mm (p/p = 0.8 %)
Antiproton Accumulation stochastic cooling for stack core stack core stack tail 160 mm (p/p = 0.8 %)
Antiproton Accumulation deceleration by HF stack core 160 mm (p/p = 0.8 %)
Antiproton Accumulation extraction kicker stack core 160 mm (p/p = 0.8 %)
FAIR / CERN / FNAL pbar Sources Increases the pbar yield by 50 % cycle time 10 s (cooling time in the CR)overallpbar yield: 5 × 10-6 pbar/p (based on CERN data) → 1 × 107 pbar/s cycle time 10 s (cooling time in the CR)overallpbar yield: 1 × 10-5 pbar/p (based on CERN data) → 2× 107 pbar/s 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
Fluka input, top view air concrete graphite iron vacuum Super FRS NESR SIS18 target CR RESR from SIS 100 atomic physics
Equivalent dose rates during operation Equivalent Dose rate [Sv/h],2 × 1013 protons per pulse, 0.1 Hz
Induced Activity after Shut-Down airplane at 12000 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 × 10-5 pbar per primary proton (4 × 107 pbar / s) • Yield(out of RESR):~ 1 × 10-5 pbar per primary proton (2 × 107 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